Some minimal typing and removal of allow-none

IPython/core/completer.py

@@ -1,3346 +1,3346 b''
 """Completion for IPython.
 
 This module started as fork of the rlcompleter module in the Python standard
 library.  The original enhancements made to rlcompleter have been sent
 upstream and were accepted as of Python 2.3,
 
 This module now support a wide variety of completion mechanism both available
 for normal classic Python code, as well as completer for IPython specific
 Syntax like magics.
 
 Latex and Unicode completion
 ============================
 
 IPython and compatible frontends not only can complete your code, but can help
 you to input a wide range of characters. In particular we allow you to insert
 a unicode character using the tab completion mechanism.
 
 Forward latex/unicode completion
 --------------------------------
 
 Forward completion allows you to easily type a unicode character using its latex
 name, or unicode long description. To do so type a backslash follow by the
 relevant name and press tab:
 
 
 Using latex completion:
 
 .. code::
 
     \\alpha<tab>
     α
 
 or using unicode completion:
 
 
 .. code::
 
     \\GREEK SMALL LETTER ALPHA<tab>
     α
 
 
 Only valid Python identifiers will complete. Combining characters (like arrow or
 dots) are also available, unlike latex they need to be put after the their
 counterpart that is to say, ``F\\\\vec<tab>`` is correct, not ``\\\\vec<tab>F``.
 
 Some browsers are known to display combining characters incorrectly.
 
 Backward latex completion
 -------------------------
 
 It is sometime challenging to know how to type a character, if you are using
 IPython, or any compatible frontend you can prepend backslash to the character
 and press :kbd:`Tab` to expand it to its latex form.
 
 .. code::
 
     \\α<tab>
     \\alpha
 
 
 Both forward and backward completions can be deactivated by setting the
 :std:configtrait:`Completer.backslash_combining_completions` option to
 ``False``.
 
 
 Experimental
 ============
 
 Starting with IPython 6.0, this module can make use of the Jedi library to
 generate completions both using static analysis of the code, and dynamically
 inspecting multiple namespaces. Jedi is an autocompletion and static analysis
 for Python. The APIs attached to this new mechanism is unstable and will
 raise unless use in an :any:`provisionalcompleter` context manager.
 
 You will find that the following are experimental:
 
     - :any:`provisionalcompleter`
     - :any:`IPCompleter.completions`
     - :any:`Completion`
     - :any:`rectify_completions`
 
 .. note::
 
     better name for :any:`rectify_completions` ?
 
 We welcome any feedback on these new API, and we also encourage you to try this
 module in debug mode (start IPython with ``--Completer.debug=True``) in order
 to have extra logging information if :any:`jedi` is crashing, or if current
 IPython completer pending deprecations are returning results not yet handled
 by :any:`jedi`
 
 Using Jedi for tab completion allow snippets like the following to work without
 having to execute any code:
 
    >>> myvar = ['hello', 42]
    ... myvar[1].bi<tab>
 
 Tab completion will be able to infer that ``myvar[1]`` is a real number without
 executing almost any code unlike the deprecated :any:`IPCompleter.greedy`
 option.
 
 Be sure to update :any:`jedi` to the latest stable version or to try the
 current development version to get better completions.
 
 Matchers
 ========
 
 All completions routines are implemented using unified *Matchers* API.
 The matchers API is provisional and subject to change without notice.
 
 The built-in matchers include:
 
 - :any:`IPCompleter.dict_key_matcher`:  dictionary key completions,
 - :any:`IPCompleter.magic_matcher`: completions for magics,
 - :any:`IPCompleter.unicode_name_matcher`,
   :any:`IPCompleter.fwd_unicode_matcher`
   and :any:`IPCompleter.latex_name_matcher`: see `Forward latex/unicode completion`_,
 - :any:`back_unicode_name_matcher` and :any:`back_latex_name_matcher`: see `Backward latex completion`_,
 - :any:`IPCompleter.file_matcher`: paths to files and directories,
 - :any:`IPCompleter.python_func_kw_matcher` - function keywords,
 - :any:`IPCompleter.python_matches` - globals and attributes (v1 API),
 - ``IPCompleter.jedi_matcher`` - static analysis with Jedi,
 - :any:`IPCompleter.custom_completer_matcher` - pluggable completer with a default
   implementation in :any:`InteractiveShell` which uses IPython hooks system
   (`complete_command`) with string dispatch (including regular expressions).
   Differently to other matchers, ``custom_completer_matcher`` will not suppress
   Jedi results to match behaviour in earlier IPython versions.
 
 Custom matchers can be added by appending to ``IPCompleter.custom_matchers`` list.
 
 Matcher API
 -----------
 
 Simplifying some details, the ``Matcher`` interface can described as
 
 .. code-block::
 
     MatcherAPIv1 = Callable[[str], list[str]]
     MatcherAPIv2 = Callable[[CompletionContext], SimpleMatcherResult]
 
     Matcher = MatcherAPIv1 | MatcherAPIv2
 
 The ``MatcherAPIv1`` reflects the matcher API as available prior to IPython 8.6.0
 and remains supported as a simplest way for generating completions. This is also
 currently the only API supported by the IPython hooks system `complete_command`.
 
 To distinguish between matcher versions ``matcher_api_version`` attribute is used.
 More precisely, the API allows to omit ``matcher_api_version`` for v1 Matchers,
 and requires a literal ``2`` for v2 Matchers.
 
 Once the API stabilises future versions may relax the requirement for specifying
 ``matcher_api_version`` by switching to :any:`functools.singledispatch`, therefore
 please do not rely on the presence of ``matcher_api_version`` for any purposes.
 
 Suppression of competing matchers
 ---------------------------------
 
 By default results from all matchers are combined, in the order determined by
 their priority. Matchers can request to suppress results from subsequent
 matchers by setting ``suppress`` to ``True`` in the ``MatcherResult``.
 
 When multiple matchers simultaneously request surpression, the results from of
 the matcher with higher priority will be returned.
 
 Sometimes it is desirable to suppress most but not all other matchers;
 this can be achieved by adding a set of identifiers of matchers which
 should not be suppressed to ``MatcherResult`` under ``do_not_suppress`` key.
 
 The suppression behaviour can is user-configurable via
 :std:configtrait:`IPCompleter.suppress_competing_matchers`.
 """
 
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 #
 # Some of this code originated from rlcompleter in the Python standard library
 # Copyright (C) 2001 Python Software Foundation, www.python.org
 
 from __future__ import annotations
 import builtins as builtin_mod
 import enum
 import glob
 import inspect
 import itertools
 import keyword
 import os
 import re
 import string
 import sys
 import tokenize
 import time
 import unicodedata
 import uuid
 import warnings
 from ast import literal_eval
 from collections import defaultdict
 from contextlib import contextmanager
 from dataclasses import dataclass
 from functools import cached_property, partial
 from types import SimpleNamespace
 from typing import (
     Iterable,
     Iterator,
     List,
     Tuple,
     Union,
     Any,
     Sequence,
     Dict,
     Optional,
     TYPE_CHECKING,
     Set,
     Sized,
     TypeVar,
     Literal,
 )
 
 from IPython.core.guarded_eval import guarded_eval, EvaluationContext
 from IPython.core.error import TryNext
 from IPython.core.inputtransformer2 import ESC_MAGIC
 from IPython.core.latex_symbols import latex_symbols, reverse_latex_symbol
 from IPython.core.oinspect import InspectColors
 from IPython.testing.skipdoctest import skip_doctest
 from IPython.utils import generics
 from IPython.utils.decorators import sphinx_options
 from IPython.utils.dir2 import dir2, get_real_method
 from IPython.utils.docs import GENERATING_DOCUMENTATION
 from IPython.utils.path import ensure_dir_exists
 from IPython.utils.process import arg_split
 from traitlets import (
     Bool,
     Enum,
     Int,
     List as ListTrait,
     Unicode,
     Dict as DictTrait,
     Union as UnionTrait,
     observe,
 )
 from traitlets.config.configurable import Configurable
 
 import __main__
 
 # skip module docstests
 __skip_doctest__ = True
 
 
 try:
     import jedi
     jedi.settings.case_insensitive_completion = False
     import jedi.api.helpers
     import jedi.api.classes
     JEDI_INSTALLED = True
 except ImportError:
     JEDI_INSTALLED = False
 
 
 if TYPE_CHECKING or GENERATING_DOCUMENTATION and sys.version_info >= (3, 11):
     from typing import cast
     from typing_extensions import TypedDict, NotRequired, Protocol, TypeAlias, TypeGuard
 else:
     from typing import Generic
 
     def cast(type_, obj):
         """Workaround for `TypeError: MatcherAPIv2() takes no arguments`"""
         return obj
 
     # do not require on runtime
     NotRequired = Tuple  # requires Python >=3.11
     TypedDict = Dict  # by extension of `NotRequired` requires 3.11 too
     Protocol = object  # requires Python >=3.8
     TypeAlias = Any  # requires Python >=3.10
     TypeGuard = Generic  # requires Python >=3.10
 if GENERATING_DOCUMENTATION:
     from typing import TypedDict
 
 # -----------------------------------------------------------------------------
 # Globals
 #-----------------------------------------------------------------------------
 
 # ranges where we have most of the valid unicode names. We could be more finer
 # grained but is it worth it for performance  While unicode have character in the
 # range 0, 0x110000, we seem to have name for about 10% of those. (131808 as I
 # write this). With below range we cover them all, with a density of ~67%
 # biggest next gap we consider only adds up about 1% density and there are 600
 # gaps that would need hard coding.
 _UNICODE_RANGES = [(32, 0x323B0), (0xE0001, 0xE01F0)]
 
 # Public API
 __all__ = ["Completer", "IPCompleter"]
 
 if sys.platform == 'win32':
     PROTECTABLES = ' '
 else:
     PROTECTABLES = ' ()[]{}?=\\|;:\'#*"^&'
 
 # Protect against returning an enormous number of completions which the frontend
 # may have trouble processing.
 MATCHES_LIMIT = 500
 
 # Completion type reported when no type can be inferred.
 _UNKNOWN_TYPE = "<unknown>"
 
 # sentinel value to signal lack of a match
 not_found = object()
 
 class ProvisionalCompleterWarning(FutureWarning):
     """
     Exception raise by an experimental feature in this module.
 
     Wrap code in :any:`provisionalcompleter` context manager if you
     are certain you want to use an unstable feature.
     """
     pass
 
 warnings.filterwarnings('error', category=ProvisionalCompleterWarning)
 
 
 @skip_doctest
 @contextmanager
 def provisionalcompleter(action='ignore'):
     """
     This context manager has to be used in any place where unstable completer
     behavior and API may be called.
 
     >>> with provisionalcompleter():
     ...     completer.do_experimental_things() # works
 
     >>> completer.do_experimental_things() # raises.
 
     .. note::
 
         Unstable
 
         By using this context manager you agree that the API in use may change
         without warning, and that you won't complain if they do so.
 
         You also understand that, if the API is not to your liking, you should report
         a bug to explain your use case upstream.
 
         We'll be happy to get your feedback, feature requests, and improvements on
         any of the unstable APIs!
     """
     with warnings.catch_warnings():
         warnings.filterwarnings(action, category=ProvisionalCompleterWarning)
         yield
 
 
 def has_open_quotes(s):
     """Return whether a string has open quotes.
 
     This simply counts whether the number of quote characters of either type in
     the string is odd.
 
     Returns
     -------
     If there is an open quote, the quote character is returned.  Else, return
     False.
     """
     # We check " first, then ', so complex cases with nested quotes will get
     # the " to take precedence.
     if s.count('"') % 2:
         return '"'
     elif s.count("'") % 2:
         return "'"
     else:
         return False
 
 
 def protect_filename(s, protectables=PROTECTABLES):
     """Escape a string to protect certain characters."""
     if set(s) & set(protectables):
         if sys.platform == "win32":
             return '"' + s + '"'
         else:
             return "".join(("\\" + c if c in protectables else c) for c in s)
     else:
         return s
 
 
 def expand_user(path:str) -> Tuple[str, bool, str]:
     """Expand ``~``-style usernames in strings.
 
     This is similar to :func:`os.path.expanduser`, but it computes and returns
     extra information that will be useful if the input was being used in
     computing completions, and you wish to return the completions with the
     original '~' instead of its expanded value.
 
     Parameters
     ----------
     path : str
         String to be expanded.  If no ~ is present, the output is the same as the
         input.
 
     Returns
     -------
     newpath : str
         Result of ~ expansion in the input path.
     tilde_expand : bool
         Whether any expansion was performed or not.
     tilde_val : str
         The value that ~ was replaced with.
     """
     # Default values
     tilde_expand = False
     tilde_val = ''
     newpath = path
 
     if path.startswith('~'):
         tilde_expand = True
         rest = len(path)-1
         newpath = os.path.expanduser(path)
         if rest:
             tilde_val = newpath[:-rest]
         else:
             tilde_val = newpath
 
     return newpath, tilde_expand, tilde_val
 
 
 def compress_user(path:str, tilde_expand:bool, tilde_val:str) -> str:
     """Does the opposite of expand_user, with its outputs.
     """
     if tilde_expand:
         return path.replace(tilde_val, '~')
     else:
         return path
 
 
 def completions_sorting_key(word):
     """key for sorting completions
 
     This does several things:
 
     - Demote any completions starting with underscores to the end
     - Insert any %magic and %%cellmagic completions in the alphabetical order
       by their name
     """
     prio1, prio2 = 0, 0
 
     if word.startswith('__'):
         prio1 = 2
     elif word.startswith('_'):
         prio1 = 1
 
     if word.endswith('='):
         prio1 = -1
 
     if word.startswith('%%'):
         # If there's another % in there, this is something else, so leave it alone
         if not "%" in word[2:]:
             word = word[2:]
             prio2 = 2
     elif word.startswith('%'):
         if not "%" in word[1:]:
             word = word[1:]
             prio2 = 1
 
     return prio1, word, prio2
 
 
 class _FakeJediCompletion:
     """
     This is a workaround to communicate to the UI that Jedi has crashed and to
     report a bug. Will be used only id :any:`IPCompleter.debug` is set to true.
 
     Added in IPython 6.0 so should likely be removed for 7.0
 
     """
 
     def __init__(self, name):
 
         self.name = name
         self.complete = name
         self.type = 'crashed'
         self.name_with_symbols = name
         self.signature = ""
         self._origin = "fake"
         self.text = "crashed"
 
     def __repr__(self):
         return '<Fake completion object jedi has crashed>'
 
 
 _JediCompletionLike = Union["jedi.api.Completion", _FakeJediCompletion]
 
 
 class Completion:
     """
     Completion object used and returned by IPython completers.
 
     .. warning::
 
         Unstable
 
         This function is unstable, API may change without warning.
         It will also raise unless use in proper context manager.
 
     This act as a middle ground :any:`Completion` object between the
     :any:`jedi.api.classes.Completion` object and the Prompt Toolkit completion
     object. While Jedi need a lot of information about evaluator and how the
     code should be ran/inspected, PromptToolkit (and other frontend) mostly
     need user facing information.
 
     - Which range should be replaced replaced by what.
     - Some metadata (like completion type), or meta information to displayed to
       the use user.
 
     For debugging purpose we can also store the origin of the completion (``jedi``,
     ``IPython.python_matches``, ``IPython.magics_matches``...).
     """
 
     __slots__ = ['start', 'end', 'text', 'type', 'signature', '_origin']
 
     def __init__(
         self,
         start: int,
         end: int,
         text: str,
         *,
         type: Optional[str] = None,
         _origin="",
         signature="",
     ) -> None:
         warnings.warn(
             "``Completion`` is a provisional API (as of IPython 6.0). "
             "It may change without warnings. "
             "Use in corresponding context manager.",
             category=ProvisionalCompleterWarning,
             stacklevel=2,
         )
 
         self.start = start
         self.end = end
         self.text = text
         self.type = type
         self.signature = signature
         self._origin = _origin
 
     def __repr__(self):
         return '<Completion start=%s end=%s text=%r type=%r, signature=%r,>' % \
                 (self.start, self.end, self.text, self.type or '?', self.signature or '?')
 
     def __eq__(self, other) -> bool:
         """
         Equality and hash do not hash the type (as some completer may not be
         able to infer the type), but are use to (partially) de-duplicate
         completion.
 
         Completely de-duplicating completion is a bit tricker that just
         comparing as it depends on surrounding text, which Completions are not
         aware of.
         """
         return self.start == other.start and \
             self.end == other.end and \
             self.text == other.text
 
     def __hash__(self):
         return hash((self.start, self.end, self.text))
 
 
 class SimpleCompletion:
     """Completion item to be included in the dictionary returned by new-style Matcher (API v2).
 
     .. warning::
 
         Provisional
 
         This class is used to describe the currently supported attributes of
         simple completion items, and any additional implementation details
         should not be relied on. Additional attributes may be included in
         future versions, and meaning of text disambiguated from the current
         dual meaning of "text to insert" and "text to used as a label".
     """
 
     __slots__ = ["text", "type"]
 
     def __init__(self, text: str, *, type: Optional[str] = None):
         self.text = text
         self.type = type
 
     def __repr__(self):
         return f"<SimpleCompletion text={self.text!r} type={self.type!r}>"
 
 
 class _MatcherResultBase(TypedDict):
     """Definition of dictionary to be returned by new-style Matcher (API v2)."""
 
     #: Suffix of the provided ``CompletionContext.token``, if not given defaults to full token.
     matched_fragment: NotRequired[str]
 
     #: Whether to suppress results from all other matchers (True), some
     #: matchers (set of identifiers) or none (False); default is False.
     suppress: NotRequired[Union[bool, Set[str]]]
 
     #: Identifiers of matchers which should NOT be suppressed when this matcher
     #: requests to suppress all other matchers; defaults to an empty set.
     do_not_suppress: NotRequired[Set[str]]
 
     #: Are completions already ordered and should be left as-is? default is False.
     ordered: NotRequired[bool]
 
 
 @sphinx_options(show_inherited_members=True, exclude_inherited_from=["dict"])
 class SimpleMatcherResult(_MatcherResultBase, TypedDict):
     """Result of new-style completion matcher."""
 
     # note: TypedDict is added again to the inheritance chain
     # in order to get __orig_bases__ for documentation
 
     #: List of candidate completions
     completions: Sequence[SimpleCompletion] | Iterator[SimpleCompletion]
 
 
 class _JediMatcherResult(_MatcherResultBase):
     """Matching result returned by Jedi (will be processed differently)"""
 
     #: list of candidate completions
     completions: Iterator[_JediCompletionLike]
 
 
 AnyMatcherCompletion = Union[_JediCompletionLike, SimpleCompletion]
 AnyCompletion = TypeVar("AnyCompletion", AnyMatcherCompletion, Completion)
 
 
 @dataclass
 class CompletionContext:
     """Completion context provided as an argument to matchers in the Matcher API v2."""
 
     # rationale: many legacy matchers relied on completer state (`self.text_until_cursor`)
     # which was not explicitly visible as an argument of the matcher, making any refactor
     # prone to errors; by explicitly passing `cursor_position` we can decouple the matchers
     # from the completer, and make substituting them in sub-classes easier.
 
     #: Relevant fragment of code directly preceding the cursor.
     #: The extraction of token is implemented via splitter heuristic
     #: (following readline behaviour for legacy reasons), which is user configurable
     #: (by switching the greedy mode).
     token: str
 
     #: The full available content of the editor or buffer
     full_text: str
 
     #: Cursor position in the line (the same for ``full_text`` and ``text``).
     cursor_position: int
 
     #: Cursor line in ``full_text``.
     cursor_line: int
 
     #: The maximum number of completions that will be used downstream.
     #: Matchers can use this information to abort early.
     #: The built-in Jedi matcher is currently excepted from this limit.
     # If not given, return all possible completions.
     limit: Optional[int]
 
     @cached_property
     def text_until_cursor(self) -> str:
         return self.line_with_cursor[: self.cursor_position]
 
     @cached_property
     def line_with_cursor(self) -> str:
         return self.full_text.split("\n")[self.cursor_line]
 
 
 #: Matcher results for API v2.
 MatcherResult = Union[SimpleMatcherResult, _JediMatcherResult]
 
 
 class _MatcherAPIv1Base(Protocol):
     def __call__(self, text: str) -> List[str]:
         """Call signature."""
         ...
 
     #: Used to construct the default matcher identifier
     __qualname__: str
 
 
 class _MatcherAPIv1Total(_MatcherAPIv1Base, Protocol):
     #: API version
     matcher_api_version: Optional[Literal[1]]
 
     def __call__(self, text: str) -> List[str]:
         """Call signature."""
         ...
 
 
 #: Protocol describing Matcher API v1.
 MatcherAPIv1: TypeAlias = Union[_MatcherAPIv1Base, _MatcherAPIv1Total]
 
 
 class MatcherAPIv2(Protocol):
     """Protocol describing Matcher API v2."""
 
     #: API version
     matcher_api_version: Literal[2] = 2
 
     def __call__(self, context: CompletionContext) -> MatcherResult:
         """Call signature."""
         ...
 
     #: Used to construct the default matcher identifier
     __qualname__: str
 
 
 Matcher: TypeAlias = Union[MatcherAPIv1, MatcherAPIv2]
 
 
 def _is_matcher_v1(matcher: Matcher) -> TypeGuard[MatcherAPIv1]:
     api_version = _get_matcher_api_version(matcher)
     return api_version == 1
 
 
 def _is_matcher_v2(matcher: Matcher) -> TypeGuard[MatcherAPIv2]:
     api_version = _get_matcher_api_version(matcher)
     return api_version == 2
 
 
 def _is_sizable(value: Any) -> TypeGuard[Sized]:
     """Determines whether objects is sizable"""
     return hasattr(value, "__len__")
 
 
 def _is_iterator(value: Any) -> TypeGuard[Iterator]:
     """Determines whether objects is sizable"""
     return hasattr(value, "__next__")
 
 
 def has_any_completions(result: MatcherResult) -> bool:
     """Check if any result includes any completions."""
     completions = result["completions"]
     if _is_sizable(completions):
         return len(completions) != 0
     if _is_iterator(completions):
         try:
             old_iterator = completions
             first = next(old_iterator)
             result["completions"] = cast(
                 Iterator[SimpleCompletion],
                 itertools.chain([first], old_iterator),
             )
             return True
         except StopIteration:
             return False
     raise ValueError(
         "Completions returned by matcher need to be an Iterator or a Sizable"
     )
 
 
 def completion_matcher(
     *,
     priority: Optional[float] = None,
     identifier: Optional[str] = None,
     api_version: int = 1,
 ):
     """Adds attributes describing the matcher.
 
     Parameters
     ----------
     priority : Optional[float]
         The priority of the matcher, determines the order of execution of matchers.
         Higher priority means that the matcher will be executed first. Defaults to 0.
     identifier : Optional[str]
         identifier of the matcher allowing users to modify the behaviour via traitlets,
         and also used to for debugging (will be passed as ``origin`` with the completions).
 
         Defaults to matcher function's ``__qualname__`` (for example,
         ``IPCompleter.file_matcher`` for the built-in matched defined
         as a ``file_matcher`` method of the ``IPCompleter`` class).
     api_version: Optional[int]
         version of the Matcher API used by this matcher.
         Currently supported values are 1 and 2.
         Defaults to 1.
     """
 
     def wrapper(func: Matcher):
         func.matcher_priority = priority or 0  # type: ignore
         func.matcher_identifier = identifier or func.__qualname__  # type: ignore
         func.matcher_api_version = api_version  # type: ignore
         if TYPE_CHECKING:
             if api_version == 1:
                 func = cast(MatcherAPIv1, func)
             elif api_version == 2:
                 func = cast(MatcherAPIv2, func)
         return func
 
     return wrapper
 
 
 def _get_matcher_priority(matcher: Matcher):
     return getattr(matcher, "matcher_priority", 0)
 
 
 def _get_matcher_id(matcher: Matcher):
     return getattr(matcher, "matcher_identifier", matcher.__qualname__)
 
 
 def _get_matcher_api_version(matcher):
     return getattr(matcher, "matcher_api_version", 1)
 
 
 context_matcher = partial(completion_matcher, api_version=2)
 
 
 _IC = Iterable[Completion]
 
 
 def _deduplicate_completions(text: str, completions: _IC)-> _IC:
     """
     Deduplicate a set of completions.
 
     .. warning::
 
         Unstable
 
         This function is unstable, API may change without warning.
 
     Parameters
     ----------
     text : str
         text that should be completed.
     completions : Iterator[Completion]
         iterator over the completions to deduplicate
 
     Yields
     ------
     `Completions` objects
     Completions coming from multiple sources, may be different but end up having
     the same effect when applied to ``text``. If this is the case, this will
     consider completions as equal and only emit the first encountered.
     Not folded in `completions()` yet for debugging purpose, and to detect when
     the IPython completer does return things that Jedi does not, but should be
     at some point.
     """
     completions = list(completions)
     if not completions:
         return
 
     new_start = min(c.start for c in completions)
     new_end = max(c.end for c in completions)
 
     seen = set()
     for c in completions:
         new_text = text[new_start:c.start] + c.text + text[c.end:new_end]
         if new_text not in seen:
             yield c
             seen.add(new_text)
 
 
 def rectify_completions(text: str, completions: _IC, *, _debug: bool = False) -> _IC:
     """
     Rectify a set of completions to all have the same ``start`` and ``end``
 
     .. warning::
 
         Unstable
 
         This function is unstable, API may change without warning.
         It will also raise unless use in proper context manager.
 
     Parameters
     ----------
     text : str
         text that should be completed.
     completions : Iterator[Completion]
         iterator over the completions to rectify
     _debug : bool
         Log failed completion
 
     Notes
     -----
     :any:`jedi.api.classes.Completion` s returned by Jedi may not have the same start and end, though
     the Jupyter Protocol requires them to behave like so. This will readjust
     the completion to have the same ``start`` and ``end`` by padding both
     extremities with surrounding text.
 
     During stabilisation should support a ``_debug`` option to log which
     completion are return by the IPython completer and not found in Jedi in
     order to make upstream bug report.
     """
     warnings.warn("`rectify_completions` is a provisional API (as of IPython 6.0). "
                  "It may change without warnings. "
                  "Use in corresponding context manager.",
                   category=ProvisionalCompleterWarning, stacklevel=2)
 
     completions = list(completions)
     if not completions:
         return
     starts = (c.start for c in completions)
     ends = (c.end for c in completions)
 
     new_start = min(starts)
     new_end = max(ends)
 
     seen_jedi = set()
     seen_python_matches = set()
     for c in completions:
         new_text = text[new_start:c.start] + c.text + text[c.end:new_end]
         if c._origin == 'jedi':
             seen_jedi.add(new_text)
         elif c._origin == 'IPCompleter.python_matches':
             seen_python_matches.add(new_text)
         yield Completion(new_start, new_end, new_text, type=c.type, _origin=c._origin, signature=c.signature)
     diff = seen_python_matches.difference(seen_jedi)
     if diff and _debug:
         print('IPython.python matches have extras:', diff)
 
 
 if sys.platform == 'win32':
     DELIMS = ' \t\n`!@#$^&*()=+[{]}|;\'",<>?'
 else:
     DELIMS = ' \t\n`!@#$^&*()=+[{]}\\|;:\'",<>?'
 
 GREEDY_DELIMS = ' =\r\n'
 
 
 class CompletionSplitter(object):
     """An object to split an input line in a manner similar to readline.
 
     By having our own implementation, we can expose readline-like completion in
     a uniform manner to all frontends.  This object only needs to be given the
     line of text to be split and the cursor position on said line, and it
     returns the 'word' to be completed on at the cursor after splitting the
     entire line.
 
     What characters are used as splitting delimiters can be controlled by
     setting the ``delims`` attribute (this is a property that internally
     automatically builds the necessary regular expression)"""
 
     # Private interface
 
     # A string of delimiter characters.  The default value makes sense for
     # IPython's most typical usage patterns.
     _delims = DELIMS
 
     # The expression (a normal string) to be compiled into a regular expression
     # for actual splitting.  We store it as an attribute mostly for ease of
     # debugging, since this type of code can be so tricky to debug.
     _delim_expr = None
 
     # The regular expression that does the actual splitting
     _delim_re = None
 
     def __init__(self, delims=None):
         delims = CompletionSplitter._delims if delims is None else delims
         self.delims = delims
 
     @property
     def delims(self):
         """Return the string of delimiter characters."""
         return self._delims
 
     @delims.setter
     def delims(self, delims):
         """Set the delimiters for line splitting."""
         expr = '[' + ''.join('\\'+ c for c in delims) + ']'
         self._delim_re = re.compile(expr)
         self._delims = delims
         self._delim_expr = expr
 
     def split_line(self, line, cursor_pos=None):
         """Split a line of text with a cursor at the given position.
         """
         l = line if cursor_pos is None else line[:cursor_pos]
         return self._delim_re.split(l)[-1]
 
 
 
 class Completer(Configurable):
 
     greedy = Bool(
         False,
         help="""Activate greedy completion.
 
         .. deprecated:: 8.8
             Use :std:configtrait:`Completer.evaluation` and :std:configtrait:`Completer.auto_close_dict_keys` instead.
 
         When enabled in IPython 8.8 or newer, changes configuration as follows:
 
         - ``Completer.evaluation = 'unsafe'``
         - ``Completer.auto_close_dict_keys = True``
         """,
     ).tag(config=True)
 
     evaluation = Enum(
         ("forbidden", "minimal", "limited", "unsafe", "dangerous"),
         default_value="limited",
         help="""Policy for code evaluation under completion.
 
         Successive options allow to enable more eager evaluation for better
         completion suggestions, including for nested dictionaries, nested lists,
         or even results of function calls.
         Setting ``unsafe`` or higher can lead to evaluation of arbitrary user
         code on :kbd:`Tab` with potentially unwanted or dangerous side effects.
 
         Allowed values are:
 
         - ``forbidden``: no evaluation of code is permitted,
         - ``minimal``: evaluation of literals and access to built-in namespace;
           no item/attribute evaluationm no access to locals/globals,
           no evaluation of any operations or comparisons.
         - ``limited``: access to all namespaces, evaluation of hard-coded methods
           (for example: :any:`dict.keys`, :any:`object.__getattr__`,
           :any:`object.__getitem__`) on allow-listed objects (for example:
           :any:`dict`, :any:`list`, :any:`tuple`, ``pandas.Series``),
         - ``unsafe``: evaluation of all methods and function calls but not of
           syntax with side-effects like `del x`,
         - ``dangerous``: completely arbitrary evaluation.
         """,
     ).tag(config=True)
 
     use_jedi = Bool(default_value=JEDI_INSTALLED,
                     help="Experimental: Use Jedi to generate autocompletions. "
                     "Default to True if jedi is installed.").tag(config=True)
 
     jedi_compute_type_timeout = Int(default_value=400,
         help="""Experimental: restrict time (in milliseconds) during which Jedi can compute types.
         Set to 0 to stop computing types. Non-zero value lower than 100ms may hurt
         performance by preventing jedi to build its cache.
         """).tag(config=True)
 
     debug = Bool(default_value=False,
                  help='Enable debug for the Completer. Mostly print extra '
                       'information for experimental jedi integration.')\
                       .tag(config=True)
 
     backslash_combining_completions = Bool(True,
         help="Enable unicode completions, e.g. \\alpha<tab> . "
              "Includes completion of latex commands, unicode names, and expanding "
              "unicode characters back to latex commands.").tag(config=True)
 
     auto_close_dict_keys = Bool(
         False,
         help="""
         Enable auto-closing dictionary keys.
 
         When enabled string keys will be suffixed with a final quote
         (matching the opening quote), tuple keys will also receive a
         separating comma if needed, and keys which are final will
         receive a closing bracket (``]``).
         """,
     ).tag(config=True)
 
     def __init__(self, namespace=None, global_namespace=None, **kwargs):
         """Create a new completer for the command line.
 
         Completer(namespace=ns, global_namespace=ns2) -> completer instance.
 
         If unspecified, the default namespace where completions are performed
         is __main__ (technically, __main__.__dict__). Namespaces should be
         given as dictionaries.
 
         An optional second namespace can be given.  This allows the completer
         to handle cases where both the local and global scopes need to be
         distinguished.
         """
 
         # Don't bind to namespace quite yet, but flag whether the user wants a
         # specific namespace or to use __main__.__dict__. This will allow us
         # to bind to __main__.__dict__ at completion time, not now.
         if namespace is None:
             self.use_main_ns = True
         else:
             self.use_main_ns = False
             self.namespace = namespace
 
         # The global namespace, if given, can be bound directly
         if global_namespace is None:
             self.global_namespace = {}
         else:
             self.global_namespace = global_namespace
 
         self.custom_matchers = []
 
         super(Completer, self).__init__(**kwargs)
 
     def complete(self, text, state):
         """Return the next possible completion for 'text'.
 
         This is called successively with state == 0, 1, 2, ... until it
         returns None.  The completion should begin with 'text'.
 
         """
         if self.use_main_ns:
             self.namespace = __main__.__dict__
 
         if state == 0:
             if "." in text:
                 self.matches = self.attr_matches(text)
             else:
                 self.matches = self.global_matches(text)
         try:
             return self.matches[state]
         except IndexError:
             return None
 
     def global_matches(self, text):
         """Compute matches when text is a simple name.
 
         Return a list of all keywords, built-in functions and names currently
         defined in self.namespace or self.global_namespace that match.
 
         """
         matches = []
         match_append = matches.append
         n = len(text)
         for lst in [
             keyword.kwlist,
             builtin_mod.__dict__.keys(),
             list(self.namespace.keys()),
             list(self.global_namespace.keys()),
         ]:
             for word in lst:
                 if word[:n] == text and word != "__builtins__":
                     match_append(word)
 
         snake_case_re = re.compile(r"[^_]+(_[^_]+)+?\Z")
         for lst in [list(self.namespace.keys()), list(self.global_namespace.keys())]:
             shortened = {
                 "_".join([sub[0] for sub in word.split("_")]): word
                 for word in lst
                 if snake_case_re.match(word)
             }
             for word in shortened.keys():
                 if word[:n] == text and word != "__builtins__":
                     match_append(shortened[word])
         return matches
 
     def attr_matches(self, text):
         """Compute matches when text contains a dot.
 
         Assuming the text is of the form NAME.NAME....[NAME], and is
         evaluatable in self.namespace or self.global_namespace, it will be
         evaluated and its attributes (as revealed by dir()) are used as
         possible completions.  (For class instances, class members are
         also considered.)
 
         WARNING: this can still invoke arbitrary C code, if an object
         with a __getattr__ hook is evaluated.
 
         """
         m2 = re.match(r"(.+)\.(\w*)$", self.line_buffer)
         if not m2:
             return []
         expr, attr = m2.group(1, 2)
 
         obj = self._evaluate_expr(expr)
 
         if obj is not_found:
             return []
 
         if self.limit_to__all__ and hasattr(obj, '__all__'):
             words = get__all__entries(obj)
         else:
             words = dir2(obj)
 
         try:
             words = generics.complete_object(obj, words)
         except TryNext:
             pass
         except AssertionError:
             raise
         except Exception:
             # Silence errors from completion function
             pass
         # Build match list to return
         n = len(attr)
 
         # Note: ideally we would just return words here and the prefix
         # reconciliator would know that we intend to append to rather than
         # replace the input text; this requires refactoring to return range
         # which ought to be replaced (as does jedi).
         tokens = _parse_tokens(expr)
         rev_tokens = reversed(tokens)
         skip_over = {tokenize.ENDMARKER, tokenize.NEWLINE}
         name_turn = True
 
         parts = []
         for token in rev_tokens:
             if token.type in skip_over:
                 continue
             if token.type == tokenize.NAME and name_turn:
                 parts.append(token.string)
                 name_turn = False
             elif token.type == tokenize.OP and token.string == "." and not name_turn:
                 parts.append(token.string)
                 name_turn = True
             else:
                 # short-circuit if not empty nor name token
                 break
 
         prefix_after_space = "".join(reversed(parts))
 
         return ["%s.%s" % (prefix_after_space, w) for w in words if w[:n] == attr]
 
     def _evaluate_expr(self, expr):
         obj = not_found
         done = False
         while not done and expr:
             try:
                 obj = guarded_eval(
                     expr,
                     EvaluationContext(
                         globals=self.global_namespace,
                         locals=self.namespace,
                         evaluation=self.evaluation,
                     ),
                 )
                 done = True
             except Exception as e:
                 if self.debug:
                     print("Evaluation exception", e)
                 # trim the expression to remove any invalid prefix
                 # e.g. user starts `(d[`, so we get `expr = '(d'`,
                 # where parenthesis is not closed.
                 # TODO: make this faster by reusing parts of the computation?
                 expr = expr[1:]
         return obj
 
 def get__all__entries(obj):
     """returns the strings in the __all__ attribute"""
     try:
         words = getattr(obj, '__all__')
     except:
         return []
 
     return [w for w in words if isinstance(w, str)]
 
 
 class _DictKeyState(enum.Flag):
     """Represent state of the key match in context of other possible matches.
 
     - given `d1 = {'a': 1}` completion on `d1['<tab>` will yield `{'a': END_OF_ITEM}` as there is no tuple.
     - given `d2 = {('a', 'b'): 1}`: `d2['a', '<tab>` will yield `{'b': END_OF_TUPLE}` as there is no tuple members to add beyond `'b'`.
     - given `d3 = {('a', 'b'): 1}`: `d3['<tab>` will yield `{'a': IN_TUPLE}` as `'a'` can be added.
     - given `d4 = {'a': 1, ('a', 'b'): 2}`: `d4['<tab>` will yield `{'a': END_OF_ITEM & END_OF_TUPLE}`
     """
 
     BASELINE = 0
     END_OF_ITEM = enum.auto()
     END_OF_TUPLE = enum.auto()
     IN_TUPLE = enum.auto()
 
 
 def _parse_tokens(c):
     """Parse tokens even if there is an error."""
     tokens = []
     token_generator = tokenize.generate_tokens(iter(c.splitlines()).__next__)
     while True:
         try:
             tokens.append(next(token_generator))
         except tokenize.TokenError:
             return tokens
         except StopIteration:
             return tokens
 
 
 def _match_number_in_dict_key_prefix(prefix: str) -> Union[str, None]:
     """Match any valid Python numeric literal in a prefix of dictionary keys.
 
     References:
     - https://docs.python.org/3/reference/lexical_analysis.html#numeric-literals
     - https://docs.python.org/3/library/tokenize.html
     """
     if prefix[-1].isspace():
         # if user typed a space we do not have anything to complete
         # even if there was a valid number token before
         return None
     tokens = _parse_tokens(prefix)
     rev_tokens = reversed(tokens)
     skip_over = {tokenize.ENDMARKER, tokenize.NEWLINE}
     number = None
     for token in rev_tokens:
         if token.type in skip_over:
             continue
         if number is None:
             if token.type == tokenize.NUMBER:
                 number = token.string
                 continue
             else:
                 # we did not match a number
                 return None
         if token.type == tokenize.OP:
             if token.string == ",":
                 break
             if token.string in {"+", "-"}:
                 number = token.string + number
         else:
             return None
     return number
 
 
 _INT_FORMATS = {
     "0b": bin,
     "0o": oct,
     "0x": hex,
 }
 
 
 def match_dict_keys(
     keys: List[Union[str, bytes, Tuple[Union[str, bytes], ...]]],
     prefix: str,
     delims: str,
     extra_prefix: Optional[Tuple[Union[str, bytes], ...]] = None,
 ) -> Tuple[str, int, Dict[str, _DictKeyState]]:
     """Used by dict_key_matches, matching the prefix to a list of keys
 
     Parameters
     ----------
     keys
         list of keys in dictionary currently being completed.
     prefix
         Part of the text already typed by the user. E.g. `mydict[b'fo`
     delims
         String of delimiters to consider when finding the current key.
     extra_prefix : optional
         Part of the text already typed in multi-key index cases. E.g. for
         `mydict['foo', "bar", 'b`, this would be `('foo', 'bar')`.
 
     Returns
     -------
     A tuple of three elements: ``quote``, ``token_start``, ``matched``, with
     ``quote`` being the quote that need to be used to close current string.
     ``token_start`` the position where the replacement should start occurring,
     ``matches`` a dictionary of replacement/completion keys on keys and values
         indicating whether the state.
     """
     prefix_tuple = extra_prefix if extra_prefix else ()
 
     prefix_tuple_size = sum(
         [
             # for pandas, do not count slices as taking space
             not isinstance(k, slice)
             for k in prefix_tuple
         ]
     )
     text_serializable_types = (str, bytes, int, float, slice)
 
     def filter_prefix_tuple(key):
         # Reject too short keys
         if len(key) <= prefix_tuple_size:
             return False
         # Reject keys which cannot be serialised to text
         for k in key:
             if not isinstance(k, text_serializable_types):
                 return False
         # Reject keys that do not match the prefix
         for k, pt in zip(key, prefix_tuple):
             if k != pt and not isinstance(pt, slice):
                 return False
         # All checks passed!
         return True
 
     filtered_key_is_final: Dict[
         Union[str, bytes, int, float], _DictKeyState
     ] = defaultdict(lambda: _DictKeyState.BASELINE)
 
     for k in keys:
         # If at least one of the matches is not final, mark as undetermined.
         # This can happen with `d = {111: 'b', (111, 222): 'a'}` where
         # `111` appears final on first match but is not final on the second.
 
         if isinstance(k, tuple):
             if filter_prefix_tuple(k):
                 key_fragment = k[prefix_tuple_size]
                 filtered_key_is_final[key_fragment] |= (
                     _DictKeyState.END_OF_TUPLE
                     if len(k) == prefix_tuple_size + 1
                     else _DictKeyState.IN_TUPLE
                 )
         elif prefix_tuple_size > 0:
             # we are completing a tuple but this key is not a tuple,
             # so we should ignore it
             pass
         else:
             if isinstance(k, text_serializable_types):
                 filtered_key_is_final[k] |= _DictKeyState.END_OF_ITEM
 
     filtered_keys = filtered_key_is_final.keys()
 
     if not prefix:
         return "", 0, {repr(k): v for k, v in filtered_key_is_final.items()}
 
     quote_match = re.search("(?:\"|')", prefix)
     is_user_prefix_numeric = False
 
     if quote_match:
         quote = quote_match.group()
         valid_prefix = prefix + quote
         try:
             prefix_str = literal_eval(valid_prefix)
         except Exception:
             return "", 0, {}
     else:
         # If it does not look like a string, let's assume
         # we are dealing with a number or variable.
         number_match = _match_number_in_dict_key_prefix(prefix)
 
         # We do not want the key matcher to suggest variable names so we yield:
         if number_match is None:
             # The alternative would be to assume that user forgort the quote
             # and if the substring matches, suggest adding it at the start.
             return "", 0, {}
 
         prefix_str = number_match
         is_user_prefix_numeric = True
         quote = ""
 
     pattern = '[^' + ''.join('\\' + c for c in delims) + ']*$'
     token_match = re.search(pattern, prefix, re.UNICODE)
     assert token_match is not None # silence mypy
     token_start = token_match.start()
     token_prefix = token_match.group()
 
     matched: Dict[str, _DictKeyState] = {}
 
     str_key: Union[str, bytes]
 
     for key in filtered_keys:
         if isinstance(key, (int, float)):
             # User typed a number but this key is not a number.
             if not is_user_prefix_numeric:
                 continue
             str_key = str(key)
             if isinstance(key, int):
                 int_base = prefix_str[:2].lower()
                 # if user typed integer using binary/oct/hex notation:
                 if int_base in _INT_FORMATS:
                     int_format = _INT_FORMATS[int_base]
                     str_key = int_format(key)
         else:
             # User typed a string but this key is a number.
             if is_user_prefix_numeric:
                 continue
             str_key = key
         try:
             if not str_key.startswith(prefix_str):
                 continue
         except (AttributeError, TypeError, UnicodeError) as e:
             # Python 3+ TypeError on b'a'.startswith('a') or vice-versa
             continue
 
         # reformat remainder of key to begin with prefix
         rem = str_key[len(prefix_str) :]
         # force repr wrapped in '
         rem_repr = repr(rem + '"') if isinstance(rem, str) else repr(rem + b'"')
         rem_repr = rem_repr[1 + rem_repr.index("'"):-2]
         if quote == '"':
             # The entered prefix is quoted with ",
             # but the match is quoted with '.
             # A contained " hence needs escaping for comparison:
             rem_repr = rem_repr.replace('"', '\\"')
 
         # then reinsert prefix from start of token
         match = "%s%s" % (token_prefix, rem_repr)
 
         matched[match] = filtered_key_is_final[key]
     return quote, token_start, matched
 
 
 def cursor_to_position(text:str, line:int, column:int)->int:
     """
     Convert the (line,column) position of the cursor in text to an offset in a
     string.
 
     Parameters
     ----------
     text : str
         The text in which to calculate the cursor offset
     line : int
         Line of the cursor; 0-indexed
     column : int
         Column of the cursor 0-indexed
 
     Returns
     -------
     Position of the cursor in ``text``, 0-indexed.
 
     See Also
     --------
     position_to_cursor : reciprocal of this function
 
     """
     lines = text.split('\n')
     assert line <= len(lines), '{} <= {}'.format(str(line), str(len(lines)))
 
     return sum(len(l) + 1 for l in lines[:line]) + column
 
 def position_to_cursor(text:str, offset:int)->Tuple[int, int]:
     """
     Convert the position of the cursor in text (0 indexed) to a line
     number(0-indexed) and a column number (0-indexed) pair
 
     Position should be a valid position in ``text``.
 
     Parameters
     ----------
     text : str
         The text in which to calculate the cursor offset
     offset : int
         Position of the cursor in ``text``, 0-indexed.
 
     Returns
     -------
     (line, column) : (int, int)
         Line of the cursor; 0-indexed, column of the cursor 0-indexed
 
     See Also
     --------
     cursor_to_position : reciprocal of this function
 
     """
 
     assert 0 <= offset <= len(text) , "0 <= %s <= %s" % (offset , len(text))
 
     before = text[:offset]
     blines = before.split('\n')  # ! splitnes trim trailing \n
     line = before.count('\n')
     col = len(blines[-1])
     return line, col
 
 
 def _safe_isinstance(obj, module, class_name, *attrs):
     """Checks if obj is an instance of module.class_name if loaded
     """
     if module in sys.modules:
         m = sys.modules[module]
         for attr in [class_name, *attrs]:
             m = getattr(m, attr)
         return isinstance(obj, m)
 
 
 @context_matcher()
 def back_unicode_name_matcher(context: CompletionContext):
     """Match Unicode characters back to Unicode name
 
     Same as :any:`back_unicode_name_matches`, but adopted to new Matcher API.
     """
     fragment, matches = back_unicode_name_matches(context.text_until_cursor)
     return _convert_matcher_v1_result_to_v2(
         matches, type="unicode", fragment=fragment, suppress_if_matches=True
     )
 
 
 def back_unicode_name_matches(text: str) -> Tuple[str, Sequence[str]]:
     """Match Unicode characters back to Unicode name
 
     This does  ``☃`` -> ``\\snowman``
 
     Note that snowman is not a valid python3 combining character but will be expanded.
     Though it will not recombine back to the snowman character by the completion machinery.
 
     This will not either back-complete standard sequences like \\n, \\b ...
 
     .. deprecated:: 8.6
         You can use :meth:`back_unicode_name_matcher` instead.
 
     Returns
     =======
 
     Return a tuple with two elements:
 
     - The Unicode character that was matched (preceded with a backslash), or
         empty string,
     - a sequence (of 1), name for the match Unicode character, preceded by
         backslash, or empty if no match.
     """
     if len(text)<2:
         return '', ()
     maybe_slash = text[-2]
     if maybe_slash != '\\':
         return '', ()
 
     char = text[-1]
     # no expand on quote for completion in strings.
     # nor backcomplete standard ascii keys
     if char in string.ascii_letters or char in ('"',"'"):
         return '', ()
     try :
         unic = unicodedata.name(char)
         return '\\'+char,('\\'+unic,)
     except KeyError:
         pass
     return '', ()
 
 
 @context_matcher()
 def back_latex_name_matcher(context: CompletionContext):
     """Match latex characters back to unicode name
 
     Same as :any:`back_latex_name_matches`, but adopted to new Matcher API.
     """
     fragment, matches = back_latex_name_matches(context.text_until_cursor)
     return _convert_matcher_v1_result_to_v2(
         matches, type="latex", fragment=fragment, suppress_if_matches=True
     )
 
 
 def back_latex_name_matches(text: str) -> Tuple[str, Sequence[str]]:
     """Match latex characters back to unicode name
 
     This does ``\\ℵ`` -> ``\\aleph``
 
     .. deprecated:: 8.6
         You can use :meth:`back_latex_name_matcher` instead.
     """
     if len(text)<2:
         return '', ()
     maybe_slash = text[-2]
     if maybe_slash != '\\':
         return '', ()
 
 
     char = text[-1]
     # no expand on quote for completion in strings.
     # nor backcomplete standard ascii keys
     if char in string.ascii_letters or char in ('"',"'"):
         return '', ()
     try :
         latex = reverse_latex_symbol[char]
         # '\\' replace the \ as well
         return '\\'+char,[latex]
     except KeyError:
         pass
     return '', ()
 
 
 def _formatparamchildren(parameter) -> str:
     """
     Get parameter name and value from Jedi Private API
 
     Jedi does not expose a simple way to get `param=value` from its API.
 
     Parameters
     ----------
     parameter
         Jedi's function `Param`
 
     Returns
     -------
     A string like 'a', 'b=1', '*args', '**kwargs'
 
     """
     description = parameter.description
     if not description.startswith('param '):
         raise ValueError('Jedi function parameter description have change format.'
                          'Expected "param ...", found %r".' % description)
     return description[6:]
 
 def _make_signature(completion)-> str:
     """
     Make the signature from a jedi completion
 
     Parameters
     ----------
     completion : jedi.Completion
         object does not complete a function type
 
     Returns
     -------
     a string consisting of the function signature, with the parenthesis but
     without the function name. example:
     `(a, *args, b=1, **kwargs)`
 
     """
 
     # it looks like this might work on jedi 0.17
     if hasattr(completion, 'get_signatures'):
         signatures = completion.get_signatures()
         if not signatures:
             return  '(?)'
 
         c0 = completion.get_signatures()[0]
         return '('+c0.to_string().split('(', maxsplit=1)[1]
 
     return '(%s)'% ', '.join([f for f in (_formatparamchildren(p) for signature in completion.get_signatures()
                                           for p in signature.defined_names()) if f])
 
 
 _CompleteResult = Dict[str, MatcherResult]
 
 
 DICT_MATCHER_REGEX = re.compile(
     r"""(?x)
 (  # match dict-referring - or any get item object - expression
     .+
 )
 \[   # open bracket
 \s*  # and optional whitespace
 # Capture any number of serializable objects (e.g. "a", "b", 'c')
 # and slices
 ((?:(?:
     (?: # closed string
         [uUbB]?  # string prefix (r not handled)
         (?:
             '(?:[^']|(?<!\\)\\')*'
         |
             "(?:[^"]|(?<!\\)\\")*"
         )
     )
     |
         # capture integers and slices
         (?:[-+]?\d+)?(?::(?:[-+]?\d+)?){0,2}
     |
         # integer in bin/hex/oct notation
         0[bBxXoO]_?(?:\w|\d)+
     )
     \s*,\s*
 )*)
 ((?:
     (?: # unclosed string
         [uUbB]?  # string prefix (r not handled)
         (?:
             '(?:[^']|(?<!\\)\\')*
             |
             "(?:[^"]|(?<!\\)\\")*
         )
     )
     |
         # unfinished integer
         (?:[-+]?\d+)
     |
         # integer in bin/hex/oct notation
         0[bBxXoO]_?(?:\w|\d)+
     )
 )?
 $
 """
 )
 
 
 def _convert_matcher_v1_result_to_v2(
     matches: Sequence[str],
     type: str,
     fragment: Optional[str] = None,
     suppress_if_matches: bool = False,
 ) -> SimpleMatcherResult:
     """Utility to help with transition"""
     result = {
         "completions": [SimpleCompletion(text=match, type=type) for match in matches],
         "suppress": (True if matches else False) if suppress_if_matches else False,
     }
     if fragment is not None:
         result["matched_fragment"] = fragment
     return cast(SimpleMatcherResult, result)
 
 
 class IPCompleter(Completer):
     """Extension of the completer class with IPython-specific features"""
 
     @observe('greedy')
     def _greedy_changed(self, change):
         """update the splitter and readline delims when greedy is changed"""
         if change["new"]:
             self.evaluation = "unsafe"
             self.auto_close_dict_keys = True
             self.splitter.delims = GREEDY_DELIMS
         else:
             self.evaluation = "limited"
             self.auto_close_dict_keys = False
             self.splitter.delims = DELIMS
 
     dict_keys_only = Bool(
         False,
         help="""
         Whether to show dict key matches only.
 
         (disables all matchers except for `IPCompleter.dict_key_matcher`).
         """,
     )
 
     suppress_competing_matchers = UnionTrait(
         [Bool(allow_none=True), DictTrait(Bool(None, allow_none=True))],
         default_value=None,
         help="""
         Whether to suppress completions from other *Matchers*.
 
         When set to ``None`` (default) the matchers will attempt to auto-detect
         whether suppression of other matchers is desirable. For example, at
         the beginning of a line followed by `%` we expect a magic completion
         to be the only applicable option, and after ``my_dict['`` we usually
         expect a completion with an existing dictionary key.
 
         If you want to disable this heuristic and see completions from all matchers,
         set ``IPCompleter.suppress_competing_matchers = False``.
         To disable the heuristic for specific matchers provide a dictionary mapping:
         ``IPCompleter.suppress_competing_matchers = {'IPCompleter.dict_key_matcher': False}``.
 
         Set ``IPCompleter.suppress_competing_matchers = True`` to limit
         completions to the set of matchers with the highest priority;
         this is equivalent to ``IPCompleter.merge_completions`` and
         can be beneficial for performance, but will sometimes omit relevant
         candidates from matchers further down the priority list.
         """,
     ).tag(config=True)
 
     merge_completions = Bool(
         True,
         help="""Whether to merge completion results into a single list
 
         If False, only the completion results from the first non-empty
         completer will be returned.
 
         As of version 8.6.0, setting the value to ``False`` is an alias for:
         ``IPCompleter.suppress_competing_matchers = True.``.
         """,
     ).tag(config=True)
 
     disable_matchers = ListTrait(
         Unicode(),
         help="""List of matchers to disable.
 
         The list should contain matcher identifiers (see :any:`completion_matcher`).
         """,
     ).tag(config=True)
 
     omit__names = Enum(
         (0, 1, 2),
         default_value=2,
         help="""Instruct the completer to omit private method names
 
         Specifically, when completing on ``object.<tab>``.
 
         When 2 [default]: all names that start with '_' will be excluded.
 
         When 1: all 'magic' names (``__foo__``) will be excluded.
 
         When 0: nothing will be excluded.
         """
     ).tag(config=True)
     limit_to__all__ = Bool(False,
         help="""
         DEPRECATED as of version 5.0.
 
         Instruct the completer to use __all__ for the completion
 
         Specifically, when completing on ``object.<tab>``.
 
         When True: only those names in obj.__all__ will be included.
 
         When False [default]: the __all__ attribute is ignored
         """,
     ).tag(config=True)
 
     profile_completions = Bool(
         default_value=False,
         help="If True, emit profiling data for completion subsystem using cProfile."
     ).tag(config=True)
 
     profiler_output_dir = Unicode(
         default_value=".completion_profiles",
         help="Template for path at which to output profile data for completions."
     ).tag(config=True)
 
     @observe('limit_to__all__')
     def _limit_to_all_changed(self, change):
         warnings.warn('`IPython.core.IPCompleter.limit_to__all__` configuration '
             'value has been deprecated since IPython 5.0, will be made to have '
             'no effects and then removed in future version of IPython.',
             UserWarning)
 
     def __init__(
         self, shell=None, namespace=None, global_namespace=None, config=None, **kwargs
     ):
         """IPCompleter() -> completer
 
         Return a completer object.
 
         Parameters
         ----------
         shell
             a pointer to the ipython shell itself.  This is needed
             because this completer knows about magic functions, and those can
             only be accessed via the ipython instance.
         namespace : dict, optional
             an optional dict where completions are performed.
         global_namespace : dict, optional
             secondary optional dict for completions, to
             handle cases (such as IPython embedded inside functions) where
             both Python scopes are visible.
         config : Config
             traitlet's config object
         **kwargs
             passed to super class unmodified.
         """
 
         self.magic_escape = ESC_MAGIC
         self.splitter = CompletionSplitter()
 
         # _greedy_changed() depends on splitter and readline being defined:
         super().__init__(
             namespace=namespace,
             global_namespace=global_namespace,
             config=config,
             **kwargs,
         )
 
         # List where completion matches will be stored
         self.matches = []
         self.shell = shell
         # Regexp to split filenames with spaces in them
         self.space_name_re = re.compile(r'([^\\] )')
         # Hold a local ref. to glob.glob for speed
         self.glob = glob.glob
 
         # Determine if we are running on 'dumb' terminals, like (X)Emacs
         # buffers, to avoid completion problems.
         term = os.environ.get('TERM','xterm')
         self.dumb_terminal = term in ['dumb','emacs']
 
         # Special handling of backslashes needed in win32 platforms
         if sys.platform == "win32":
             self.clean_glob = self._clean_glob_win32
         else:
             self.clean_glob = self._clean_glob
 
         #regexp to parse docstring for function signature
         self.docstring_sig_re = re.compile(r'^[\w|\s.]+\(([^)]*)\).*')
         self.docstring_kwd_re = re.compile(r'[\s|\[]*(\w+)(?:\s*=\s*.*)')
         #use this if positional argument name is also needed
         #= re.compile(r'[\s|\[]*(\w+)(?:\s*=?\s*.*)')
 
         self.magic_arg_matchers = [
             self.magic_config_matcher,
             self.magic_color_matcher,
         ]
 
         # This is set externally by InteractiveShell
         self.custom_completers = None
 
         # This is a list of names of unicode characters that can be completed
         # into their corresponding unicode value. The list is large, so we
         # lazily initialize it on first use. Consuming code should access this
         # attribute through the `@unicode_names` property.
         self._unicode_names = None
 
         self._backslash_combining_matchers = [
             self.latex_name_matcher,
             self.unicode_name_matcher,
             back_latex_name_matcher,
             back_unicode_name_matcher,
             self.fwd_unicode_matcher,
         ]
 
         if not self.backslash_combining_completions:
             for matcher in self._backslash_combining_matchers:
                 self.disable_matchers.append(_get_matcher_id(matcher))
 
         if not self.merge_completions:
             self.suppress_competing_matchers = True
 
     @property
     def matchers(self) -> List[Matcher]:
         """All active matcher routines for completion"""
         if self.dict_keys_only:
             return [self.dict_key_matcher]
 
         if self.use_jedi:
             return [
                 *self.custom_matchers,
                 *self._backslash_combining_matchers,
                 *self.magic_arg_matchers,
                 self.custom_completer_matcher,
                 self.magic_matcher,
                 self._jedi_matcher,
                 self.dict_key_matcher,
                 self.file_matcher,
             ]
         else:
             return [
                 *self.custom_matchers,
                 *self._backslash_combining_matchers,
                 *self.magic_arg_matchers,
                 self.custom_completer_matcher,
                 self.dict_key_matcher,
                 # TODO: convert python_matches to v2 API
                 self.magic_matcher,
                 self.python_matches,
                 self.file_matcher,
                 self.python_func_kw_matcher,
             ]
 
     def all_completions(self, text:str) -> List[str]:
         """
         Wrapper around the completion methods for the benefit of emacs.
         """
         prefix = text.rpartition('.')[0]
         with provisionalcompleter():
             return ['.'.join([prefix, c.text]) if prefix and self.use_jedi else c.text
                     for c in self.completions(text, len(text))]
 
         return self.complete(text)[1]
 
     def _clean_glob(self, text:str):
         return self.glob("%s*" % text)
 
     def _clean_glob_win32(self, text:str):
         return [f.replace("\\","/")
                 for f in self.glob("%s*" % text)]
 
     @context_matcher()
     def file_matcher(self, context: CompletionContext) -> SimpleMatcherResult:
         """Same as :any:`file_matches`, but adopted to new Matcher API."""
         matches = self.file_matches(context.token)
         # TODO: add a heuristic for suppressing (e.g. if it has OS-specific delimiter,
         #  starts with `/home/`, `C:\`, etc)
         return _convert_matcher_v1_result_to_v2(matches, type="path")
 
     def file_matches(self, text: str) -> List[str]:
         """Match filenames, expanding ~USER type strings.
 
         Most of the seemingly convoluted logic in this completer is an
         attempt to handle filenames with spaces in them.  And yet it's not
         quite perfect, because Python's readline doesn't expose all of the
         GNU readline details needed for this to be done correctly.
 
         For a filename with a space in it, the printed completions will be
         only the parts after what's already been typed (instead of the
         full completions, as is normally done).  I don't think with the
         current (as of Python 2.3) Python readline it's possible to do
         better.
 
         .. deprecated:: 8.6
             You can use :meth:`file_matcher` instead.
         """
 
         # chars that require escaping with backslash - i.e. chars
         # that readline treats incorrectly as delimiters, but we
         # don't want to treat as delimiters in filename matching
         # when escaped with backslash
         if text.startswith('!'):
             text = text[1:]
             text_prefix = u'!'
         else:
             text_prefix = u''
 
         text_until_cursor = self.text_until_cursor
         # track strings with open quotes
         open_quotes = has_open_quotes(text_until_cursor)
 
         if '(' in text_until_cursor or '[' in text_until_cursor:
             lsplit = text
         else:
             try:
                 # arg_split ~ shlex.split, but with unicode bugs fixed by us
                 lsplit = arg_split(text_until_cursor)[-1]
             except ValueError:
                 # typically an unmatched ", or backslash without escaped char.
                 if open_quotes:
                     lsplit = text_until_cursor.split(open_quotes)[-1]
                 else:
                     return []
             except IndexError:
                 # tab pressed on empty line
                 lsplit = ""
 
         if not open_quotes and lsplit != protect_filename(lsplit):
             # if protectables are found, do matching on the whole escaped name
             has_protectables = True
             text0,text = text,lsplit
         else:
             has_protectables = False
             text = os.path.expanduser(text)
 
         if text == "":
             return [text_prefix + protect_filename(f) for f in self.glob("*")]
 
         # Compute the matches from the filesystem
         if sys.platform == 'win32':
             m0 = self.clean_glob(text)
         else:
             m0 = self.clean_glob(text.replace('\\', ''))
 
         if has_protectables:
             # If we had protectables, we need to revert our changes to the
             # beginning of filename so that we don't double-write the part
             # of the filename we have so far
             len_lsplit = len(lsplit)
             matches = [text_prefix + text0 +
                        protect_filename(f[len_lsplit:]) for f in m0]
         else:
             if open_quotes:
                 # if we have a string with an open quote, we don't need to
                 # protect the names beyond the quote (and we _shouldn't_, as
                 # it would cause bugs when the filesystem call is made).
                 matches = m0 if sys.platform == "win32" else\
                     [protect_filename(f, open_quotes) for f in m0]
             else:
                 matches = [text_prefix +
                            protect_filename(f) for f in m0]
 
         # Mark directories in input list by appending '/' to their names.
         return [x+'/' if os.path.isdir(x) else x for x in matches]
 
     @context_matcher()
     def magic_matcher(self, context: CompletionContext) -> SimpleMatcherResult:
         """Match magics."""
         text = context.token
         matches = self.magic_matches(text)
         result = _convert_matcher_v1_result_to_v2(matches, type="magic")
         is_magic_prefix = len(text) > 0 and text[0] == "%"
         result["suppress"] = is_magic_prefix and bool(result["completions"])
         return result
 
     def magic_matches(self, text: str):
         """Match magics.
 
         .. deprecated:: 8.6
             You can use :meth:`magic_matcher` instead.
         """
         # Get all shell magics now rather than statically, so magics loaded at
         # runtime show up too.
         lsm = self.shell.magics_manager.lsmagic()
         line_magics = lsm['line']
         cell_magics = lsm['cell']
         pre = self.magic_escape
         pre2 = pre+pre
 
         explicit_magic = text.startswith(pre)
 
         # Completion logic:
         # - user gives %%: only do cell magics
         # - user gives %: do both line and cell magics
         # - no prefix: do both
         # In other words, line magics are skipped if the user gives %% explicitly
         #
         # We also exclude magics that match any currently visible names:
         # https://github.com/ipython/ipython/issues/4877, unless the user has
         # typed a %:
         # https://github.com/ipython/ipython/issues/10754
         bare_text = text.lstrip(pre)
         global_matches = self.global_matches(bare_text)
         if not explicit_magic:
             def matches(magic):
                 """
                 Filter magics, in particular remove magics that match
                 a name present in global namespace.
                 """
                 return ( magic.startswith(bare_text) and
                          magic not in global_matches )
         else:
             def matches(magic):
                 return magic.startswith(bare_text)
 
         comp = [ pre2+m for m in cell_magics if matches(m)]
         if not text.startswith(pre2):
             comp += [ pre+m for m in line_magics if matches(m)]
 
         return comp
 
     @context_matcher()
     def magic_config_matcher(self, context: CompletionContext) -> SimpleMatcherResult:
         """Match class names and attributes for %config magic."""
         # NOTE: uses `line_buffer` equivalent for compatibility
         matches = self.magic_config_matches(context.line_with_cursor)
         return _convert_matcher_v1_result_to_v2(matches, type="param")
 
     def magic_config_matches(self, text: str) -> List[str]:
         """Match class names and attributes for %config magic.
 
         .. deprecated:: 8.6
             You can use :meth:`magic_config_matcher` instead.
         """
         texts = text.strip().split()
 
         if len(texts) > 0 and (texts[0] == 'config' or texts[0] == '%config'):
             # get all configuration classes
             classes = sorted(set([ c for c in self.shell.configurables
                                    if c.__class__.class_traits(config=True)
                                    ]), key=lambda x: x.__class__.__name__)
             classnames = [ c.__class__.__name__ for c in classes ]
 
             # return all classnames if config or %config is given
             if len(texts) == 1:
                 return classnames
 
             # match classname
             classname_texts = texts[1].split('.')
             classname = classname_texts[0]
             classname_matches = [ c for c in classnames
                                   if c.startswith(classname) ]
 
             # return matched classes or the matched class with attributes
             if texts[1].find('.') < 0:
                 return classname_matches
             elif len(classname_matches) == 1 and \
                             classname_matches[0] == classname:
                 cls = classes[classnames.index(classname)].__class__
                 help = cls.class_get_help()
                 # strip leading '--' from cl-args:
                 help = re.sub(re.compile(r'^--', re.MULTILINE), '', help)
                 return [ attr.split('=')[0]
                          for attr in help.strip().splitlines()
                          if attr.startswith(texts[1]) ]
         return []
 
     @context_matcher()
     def magic_color_matcher(self, context: CompletionContext) -> SimpleMatcherResult:
         """Match color schemes for %colors magic."""
         # NOTE: uses `line_buffer` equivalent for compatibility
         matches = self.magic_color_matches(context.line_with_cursor)
         return _convert_matcher_v1_result_to_v2(matches, type="param")
 
     def magic_color_matches(self, text: str) -> List[str]:
         """Match color schemes for %colors magic.
 
         .. deprecated:: 8.6
             You can use :meth:`magic_color_matcher` instead.
         """
         texts = text.split()
         if text.endswith(' '):
             # .split() strips off the trailing whitespace. Add '' back
             # so that: '%colors ' -> ['%colors', '']
             texts.append('')
 
         if len(texts) == 2 and (texts[0] == 'colors' or texts[0] == '%colors'):
             prefix = texts[1]
             return [ color for color in InspectColors.keys()
                      if color.startswith(prefix) ]
         return []
 
     @context_matcher(identifier="IPCompleter.jedi_matcher")
     def _jedi_matcher(self, context: CompletionContext) -> _JediMatcherResult:
         matches = self._jedi_matches(
             cursor_column=context.cursor_position,
             cursor_line=context.cursor_line,
             text=context.full_text,
         )
         return {
             "completions": matches,
             # static analysis should not suppress other matchers
             "suppress": False,
         }
 
     def _jedi_matches(
         self, cursor_column: int, cursor_line: int, text: str
     ) -> Iterator[_JediCompletionLike]:
         """
         Return a list of :any:`jedi.api.Completion`\\s object from a ``text`` and
         cursor position.
 
         Parameters
         ----------
         cursor_column : int
             column position of the cursor in ``text``, 0-indexed.
         cursor_line : int
             line position of the cursor in ``text``, 0-indexed
         text : str
             text to complete
 
         Notes
         -----
         If ``IPCompleter.debug`` is ``True`` may return a :any:`_FakeJediCompletion`
         object containing a string with the Jedi debug information attached.
 
         .. deprecated:: 8.6
             You can use :meth:`_jedi_matcher` instead.
         """
         namespaces = [self.namespace]
         if self.global_namespace is not None:
             namespaces.append(self.global_namespace)
 
         completion_filter = lambda x:x
         offset = cursor_to_position(text, cursor_line, cursor_column)
         # filter output if we are completing for object members
         if offset:
             pre = text[offset-1]
             if pre == '.':
                 if self.omit__names == 2:
                     completion_filter = lambda c:not c.name.startswith('_')
                 elif self.omit__names == 1:
                     completion_filter = lambda c:not (c.name.startswith('__') and c.name.endswith('__'))
                 elif self.omit__names == 0:
                     completion_filter = lambda x:x
                 else:
                     raise ValueError("Don't understand self.omit__names == {}".format(self.omit__names))
 
         interpreter = jedi.Interpreter(text[:offset], namespaces)
         try_jedi = True
 
         try:
             # find the first token in the current tree -- if it is a ' or " then we are in a string
             completing_string = False
             try:
                 first_child = next(c for c in interpreter._get_module().tree_node.children if hasattr(c, 'value'))
             except StopIteration:
                 pass
             else:
                 # note the value may be ', ", or it may also be ''' or """, or
                 # in some cases, """what/you/typed..., but all of these are
                 # strings.
                 completing_string = len(first_child.value) > 0 and first_child.value[0] in {"'", '"'}
 
             # if we are in a string jedi is likely not the right candidate for
             # now. Skip it.
             try_jedi = not completing_string
         except Exception as e:
             # many of things can go wrong, we are using private API just don't crash.
             if self.debug:
                 print("Error detecting if completing a non-finished string :", e, '|')
 
         if not try_jedi:
             return iter([])
         try:
             return filter(completion_filter, interpreter.complete(column=cursor_column, line=cursor_line + 1))
         except Exception as e:
             if self.debug:
                 return iter(
                     [
                         _FakeJediCompletion(
                             'Oops Jedi has crashed, please report a bug with the following:\n"""\n%s\ns"""'
                             % (e)
                         )
                     ]
                 )
             else:
                 return iter([])
 
     @completion_matcher(api_version=1)
     def python_matches(self, text: str) -> Iterable[str]:
         """Match attributes or global python names"""
         if "." in text:
             try:
                 matches = self.attr_matches(text)
                 if text.endswith('.') and self.omit__names:
                     if self.omit__names == 1:
                         # true if txt is _not_ a __ name, false otherwise:
                         no__name = (lambda txt:
                                     re.match(r'.*\.__.*?__',txt) is None)
                     else:
                         # true if txt is _not_ a _ name, false otherwise:
                         no__name = (lambda txt:
                                     re.match(r'\._.*?',txt[txt.rindex('.'):]) is None)
                     matches = filter(no__name, matches)
             except NameError:
                 # catches <undefined attributes>.<tab>
                 matches = []
         else:
             matches = self.global_matches(text)
         return matches
 
     def _default_arguments_from_docstring(self, doc):
         """Parse the first line of docstring for call signature.
 
         Docstring should be of the form 'min(iterable[, key=func])\n'.
         It can also parse cython docstring of the form
         'Minuit.migrad(self, int ncall=10000, resume=True, int nsplit=1)'.
         """
         if doc is None:
             return []
 
         #care only the firstline
         line = doc.lstrip().splitlines()[0]
 
         #p = re.compile(r'^[\w|\s.]+\(([^)]*)\).*')
         #'min(iterable[, key=func])\n' -> 'iterable[, key=func]'
         sig = self.docstring_sig_re.search(line)
         if sig is None:
             return []
         # iterable[, key=func]' -> ['iterable[' ,' key=func]']
         sig = sig.groups()[0].split(',')
         ret = []
         for s in sig:
             #re.compile(r'[\s|\[]*(\w+)(?:\s*=\s*.*)')
             ret += self.docstring_kwd_re.findall(s)
         return ret
 
     def _default_arguments(self, obj):
         """Return the list of default arguments of obj if it is callable,
         or empty list otherwise."""
         call_obj = obj
         ret = []
         if inspect.isbuiltin(obj):
             pass
         elif not (inspect.isfunction(obj) or inspect.ismethod(obj)):
             if inspect.isclass(obj):
                 #for cython embedsignature=True the constructor docstring
                 #belongs to the object itself not __init__
                 ret += self._default_arguments_from_docstring(
                             getattr(obj, '__doc__', ''))
                 # for classes, check for __init__,__new__
                 call_obj = (getattr(obj, '__init__', None) or
                        getattr(obj, '__new__', None))
             # for all others, check if they are __call__able
             elif hasattr(obj, '__call__'):
                 call_obj = obj.__call__
         ret += self._default_arguments_from_docstring(
                  getattr(call_obj, '__doc__', ''))
 
         _keeps = (inspect.Parameter.KEYWORD_ONLY,
                   inspect.Parameter.POSITIONAL_OR_KEYWORD)
 
         try:
             sig = inspect.signature(obj)
             ret.extend(k for k, v in sig.parameters.items() if
                        v.kind in _keeps)
         except ValueError:
             pass
 
         return list(set(ret))
 
     @context_matcher()
     def python_func_kw_matcher(self, context: CompletionContext) -> SimpleMatcherResult:
         """Match named parameters (kwargs) of the last open function."""
         matches = self.python_func_kw_matches(context.token)
         return _convert_matcher_v1_result_to_v2(matches, type="param")
 
     def python_func_kw_matches(self, text):
         """Match named parameters (kwargs) of the last open function.
 
         .. deprecated:: 8.6
             You can use :meth:`python_func_kw_matcher` instead.
         """
 
         if "." in text: # a parameter cannot be dotted
             return []
         try: regexp = self.__funcParamsRegex
         except AttributeError:
             regexp = self.__funcParamsRegex = re.compile(r'''
                 '.*?(?<!\\)' |    # single quoted strings or
                 ".*?(?<!\\)" |    # double quoted strings or
                 \w+          |    # identifier
                 \S                # other characters
                 ''', re.VERBOSE | re.DOTALL)
         # 1. find the nearest identifier that comes before an unclosed
         # parenthesis before the cursor
         # e.g. for "foo (1+bar(x), pa<cursor>,a=1)", the candidate is "foo"
         tokens = regexp.findall(self.text_until_cursor)
         iterTokens = reversed(tokens); openPar = 0
 
         for token in iterTokens:
             if token == ')':
                 openPar -= 1
             elif token == '(':
                 openPar += 1
                 if openPar > 0:
                     # found the last unclosed parenthesis
                     break
         else:
             return []
         # 2. Concatenate dotted names ("foo.bar" for "foo.bar(x, pa" )
         ids = []
         isId = re.compile(r'\w+$').match
 
         while True:
             try:
                 ids.append(next(iterTokens))
                 if not isId(ids[-1]):
                     ids.pop(); break
                 if not next(iterTokens) == '.':
                     break
             except StopIteration:
                 break
 
         # Find all named arguments already assigned to, as to avoid suggesting
         # them again
         usedNamedArgs = set()
         par_level = -1
         for token, next_token in zip(tokens, tokens[1:]):
             if token == '(':
                 par_level += 1
             elif token == ')':
                 par_level -= 1
 
             if par_level != 0:
                 continue
 
             if next_token != '=':
                 continue
 
             usedNamedArgs.add(token)
 
         argMatches = []
         try:
             callableObj = '.'.join(ids[::-1])
             namedArgs = self._default_arguments(eval(callableObj,
                                                     self.namespace))
 
             # Remove used named arguments from the list, no need to show twice
             for namedArg in set(namedArgs) - usedNamedArgs:
                 if namedArg.startswith(text):
                     argMatches.append("%s=" %namedArg)
         except:
             pass
 
         return argMatches
 
     @staticmethod
     def _get_keys(obj: Any) -> List[Any]:
         # Objects can define their own completions by defining an
         # _ipy_key_completions_() method.
         method = get_real_method(obj, '_ipython_key_completions_')
         if method is not None:
             return method()
 
         # Special case some common in-memory dict-like types
         if isinstance(obj, dict) or _safe_isinstance(obj, "pandas", "DataFrame"):
             try:
                 return list(obj.keys())
             except Exception:
                 return []
         elif _safe_isinstance(obj, "pandas", "core", "indexing", "_LocIndexer"):
             try:
                 return list(obj.obj.keys())
             except Exception:
                 return []
         elif _safe_isinstance(obj, 'numpy', 'ndarray') or\
              _safe_isinstance(obj, 'numpy', 'void'):
             return obj.dtype.names or []
         return []
 
     @context_matcher()
     def dict_key_matcher(self, context: CompletionContext) -> SimpleMatcherResult:
         """Match string keys in a dictionary, after e.g. ``foo[``."""
         matches = self.dict_key_matches(context.token)
         return _convert_matcher_v1_result_to_v2(
             matches, type="dict key", suppress_if_matches=True
         )
 
     def dict_key_matches(self, text: str) -> List[str]:
         """Match string keys in a dictionary, after e.g. ``foo[``.
 
         .. deprecated:: 8.6
             You can use :meth:`dict_key_matcher` instead.
         """
 
         # Short-circuit on closed dictionary (regular expression would
         # not match anyway, but would take quite a while).
         if self.text_until_cursor.strip().endswith("]"):
             return []
 
         match = DICT_MATCHER_REGEX.search(self.text_until_cursor)
 
         if match is None:
             return []
 
         expr, prior_tuple_keys, key_prefix = match.groups()
 
         obj = self._evaluate_expr(expr)
 
         if obj is not_found:
             return []
 
         keys = self._get_keys(obj)
         if not keys:
             return keys
 
         tuple_prefix = guarded_eval(
             prior_tuple_keys,
             EvaluationContext(
                 globals=self.global_namespace,
                 locals=self.namespace,
-                evaluation=self.evaluation,
+                evaluation=self.evaluation,  # type: ignore
                 in_subscript=True,
             ),
         )
 
         closing_quote, token_offset, matches = match_dict_keys(
             keys, key_prefix, self.splitter.delims, extra_prefix=tuple_prefix
         )
         if not matches:
             return []
 
         # get the cursor position of
         # - the text being completed
         # - the start of the key text
         # - the start of the completion
         text_start = len(self.text_until_cursor) - len(text)
         if key_prefix:
             key_start = match.start(3)
             completion_start = key_start + token_offset
         else:
             key_start = completion_start = match.end()
 
         # grab the leading prefix, to make sure all completions start with `text`
         if text_start > key_start:
             leading = ''
         else:
             leading = text[text_start:completion_start]
 
         # append closing quote and bracket as appropriate
         # this is *not* appropriate if the opening quote or bracket is outside
         # the text given to this method, e.g. `d["""a\nt
         can_close_quote = False
         can_close_bracket = False
 
         continuation = self.line_buffer[len(self.text_until_cursor) :].strip()
 
         if continuation.startswith(closing_quote):
             # do not close if already closed, e.g. `d['a<tab>'`
             continuation = continuation[len(closing_quote) :]
         else:
             can_close_quote = True
 
         continuation = continuation.strip()
 
         # e.g. `pandas.DataFrame` has different tuple indexer behaviour,
         # handling it is out of scope, so let's avoid appending suffixes.
         has_known_tuple_handling = isinstance(obj, dict)
 
         can_close_bracket = (
             not continuation.startswith("]") and self.auto_close_dict_keys
         )
         can_close_tuple_item = (
             not continuation.startswith(",")
             and has_known_tuple_handling
             and self.auto_close_dict_keys
         )
         can_close_quote = can_close_quote and self.auto_close_dict_keys
 
         # fast path if closing qoute should be appended but not suffix is allowed
         if not can_close_quote and not can_close_bracket and closing_quote:
             return [leading + k for k in matches]
 
         results = []
 
         end_of_tuple_or_item = _DictKeyState.END_OF_TUPLE | _DictKeyState.END_OF_ITEM
 
         for k, state_flag in matches.items():
             result = leading + k
             if can_close_quote and closing_quote:
                 result += closing_quote
 
             if state_flag == end_of_tuple_or_item:
                 # We do not know which suffix to add,
                 # e.g. both tuple item and string
                 # match this item.
                 pass
 
             if state_flag in end_of_tuple_or_item and can_close_bracket:
                 result += "]"
             if state_flag == _DictKeyState.IN_TUPLE and can_close_tuple_item:
                 result += ", "
             results.append(result)
         return results
 
     @context_matcher()
     def unicode_name_matcher(self, context: CompletionContext):
         """Same as :any:`unicode_name_matches`, but adopted to new Matcher API."""
         fragment, matches = self.unicode_name_matches(context.text_until_cursor)
         return _convert_matcher_v1_result_to_v2(
             matches, type="unicode", fragment=fragment, suppress_if_matches=True
         )
 
     @staticmethod
     def unicode_name_matches(text: str) -> Tuple[str, List[str]]:
         """Match Latex-like syntax for unicode characters base
         on the name of the character.
 
         This does  ``\\GREEK SMALL LETTER ETA`` -> ``η``
 
         Works only on valid python 3 identifier, or on combining characters that
         will combine to form a valid identifier.
         """
         slashpos = text.rfind('\\')
         if slashpos > -1:
             s = text[slashpos+1:]
             try :
                 unic = unicodedata.lookup(s)
                 # allow combining chars
                 if ('a'+unic).isidentifier():
                     return '\\'+s,[unic]
             except KeyError:
                 pass
         return '', []
 
     @context_matcher()
     def latex_name_matcher(self, context: CompletionContext):
         """Match Latex syntax for unicode characters.
 
         This does both ``\\alp`` -> ``\\alpha`` and ``\\alpha`` -> ``α``
         """
         fragment, matches = self.latex_matches(context.text_until_cursor)
         return _convert_matcher_v1_result_to_v2(
             matches, type="latex", fragment=fragment, suppress_if_matches=True
         )
 
     def latex_matches(self, text: str) -> Tuple[str, Sequence[str]]:
         """Match Latex syntax for unicode characters.
 
         This does both ``\\alp`` -> ``\\alpha`` and ``\\alpha`` -> ``α``
 
         .. deprecated:: 8.6
             You can use :meth:`latex_name_matcher` instead.
         """
         slashpos = text.rfind('\\')
         if slashpos > -1:
             s = text[slashpos:]
             if s in latex_symbols:
                 # Try to complete a full latex symbol to unicode
                 # \\alpha -> α
                 return s, [latex_symbols[s]]
             else:
                 # If a user has partially typed a latex symbol, give them
                 # a full list of options \al -> [\aleph, \alpha]
                 matches = [k for k in latex_symbols if k.startswith(s)]
                 if matches:
                     return s, matches
         return '', ()
 
     @context_matcher()
     def custom_completer_matcher(self, context):
         """Dispatch custom completer.
 
         If a match is found, suppresses all other matchers except for Jedi.
         """
         matches = self.dispatch_custom_completer(context.token) or []
         result = _convert_matcher_v1_result_to_v2(
             matches, type=_UNKNOWN_TYPE, suppress_if_matches=True
         )
         result["ordered"] = True
         result["do_not_suppress"] = {_get_matcher_id(self._jedi_matcher)}
         return result
 
     def dispatch_custom_completer(self, text):
         """
         .. deprecated:: 8.6
             You can use :meth:`custom_completer_matcher` instead.
         """
         if not self.custom_completers:
             return
 
         line = self.line_buffer
         if not line.strip():
             return None
 
         # Create a little structure to pass all the relevant information about
         # the current completion to any custom completer.
         event = SimpleNamespace()
         event.line = line
         event.symbol = text
         cmd = line.split(None,1)[0]
         event.command = cmd
         event.text_until_cursor = self.text_until_cursor
 
         # for foo etc, try also to find completer for %foo
         if not cmd.startswith(self.magic_escape):
             try_magic = self.custom_completers.s_matches(
                 self.magic_escape + cmd)
         else:
             try_magic = []
 
         for c in itertools.chain(self.custom_completers.s_matches(cmd),
                  try_magic,
                  self.custom_completers.flat_matches(self.text_until_cursor)):
             try:
                 res = c(event)
                 if res:
                     # first, try case sensitive match
                     withcase = [r for r in res if r.startswith(text)]
                     if withcase:
                         return withcase
                     # if none, then case insensitive ones are ok too
                     text_low = text.lower()
                     return [r for r in res if r.lower().startswith(text_low)]
             except TryNext:
                 pass
             except KeyboardInterrupt:
                 """
                 If custom completer take too long,
                 let keyboard interrupt abort and return nothing.
                 """
                 break
 
         return None
 
     def completions(self, text: str, offset: int)->Iterator[Completion]:
         """
         Returns an iterator over the possible completions
 
         .. warning::
 
             Unstable
 
             This function is unstable, API may change without warning.
             It will also raise unless use in proper context manager.
 
         Parameters
         ----------
         text : str
             Full text of the current input, multi line string.
         offset : int
             Integer representing the position of the cursor in ``text``. Offset
             is 0-based indexed.
 
         Yields
         ------
         Completion
 
         Notes
         -----
         The cursor on a text can either be seen as being "in between"
         characters or "On" a character depending on the interface visible to
         the user. For consistency the cursor being on "in between" characters X
         and Y is equivalent to the cursor being "on" character Y, that is to say
         the character the cursor is on is considered as being after the cursor.
 
         Combining characters may span more that one position in the
         text.
 
         .. note::
 
             If ``IPCompleter.debug`` is :any:`True` will yield a ``--jedi/ipython--``
             fake Completion token to distinguish completion returned by Jedi
             and usual IPython completion.
 
         .. note::
 
             Completions are not completely deduplicated yet. If identical
             completions are coming from different sources this function does not
             ensure that each completion object will only be present once.
         """
         warnings.warn("_complete is a provisional API (as of IPython 6.0). "
                       "It may change without warnings. "
                       "Use in corresponding context manager.",
                       category=ProvisionalCompleterWarning, stacklevel=2)
 
         seen = set()
         profiler:Optional[cProfile.Profile]
         try:
             if self.profile_completions:
                 import cProfile
                 profiler = cProfile.Profile()
                 profiler.enable()
             else:
                 profiler = None
 
             for c in self._completions(text, offset, _timeout=self.jedi_compute_type_timeout/1000):
                 if c and (c in seen):
                     continue
                 yield c
                 seen.add(c)
         except KeyboardInterrupt:
             """if completions take too long and users send keyboard interrupt,
             do not crash and return ASAP. """
             pass
         finally:
             if profiler is not None:
                 profiler.disable()
                 ensure_dir_exists(self.profiler_output_dir)
                 output_path = os.path.join(self.profiler_output_dir, str(uuid.uuid4()))
                 print("Writing profiler output to", output_path)
                 profiler.dump_stats(output_path)
 
     def _completions(self, full_text: str, offset: int, *, _timeout) -> Iterator[Completion]:
         """
         Core completion module.Same signature as :any:`completions`, with the
         extra `timeout` parameter (in seconds).
 
         Computing jedi's completion ``.type`` can be quite expensive (it is a
         lazy property) and can require some warm-up, more warm up than just
         computing the ``name`` of a completion. The warm-up can be :
 
             - Long warm-up the first time a module is encountered after
             install/update: actually build parse/inference tree.
 
             - first time the module is encountered in a session: load tree from
             disk.
 
         We don't want to block completions for tens of seconds so we give the
         completer a "budget" of ``_timeout`` seconds per invocation to compute
         completions types, the completions that have not yet been computed will
         be marked as "unknown" an will have a chance to be computed next round
         are things get cached.
 
         Keep in mind that Jedi is not the only thing treating the completion so
         keep the timeout short-ish as if we take more than 0.3 second we still
         have lots of processing to do.
 
         """
         deadline = time.monotonic() + _timeout
 
         before = full_text[:offset]
         cursor_line, cursor_column = position_to_cursor(full_text, offset)
 
         jedi_matcher_id = _get_matcher_id(self._jedi_matcher)
 
         def is_non_jedi_result(
             result: MatcherResult, identifier: str
         ) -> TypeGuard[SimpleMatcherResult]:
             return identifier != jedi_matcher_id
 
         results = self._complete(
             full_text=full_text, cursor_line=cursor_line, cursor_pos=cursor_column
         )
 
         non_jedi_results: Dict[str, SimpleMatcherResult] = {
             identifier: result
             for identifier, result in results.items()
             if is_non_jedi_result(result, identifier)
         }
 
         jedi_matches = (
             cast(_JediMatcherResult, results[jedi_matcher_id])["completions"]
             if jedi_matcher_id in results
             else ()
         )
 
         iter_jm = iter(jedi_matches)
         if _timeout:
             for jm in iter_jm:
                 try:
                     type_ = jm.type
                 except Exception:
                     if self.debug:
                         print("Error in Jedi getting type of ", jm)
                     type_ = None
                 delta = len(jm.name_with_symbols) - len(jm.complete)
                 if type_ == 'function':
                     signature = _make_signature(jm)
                 else:
                     signature = ''
                 yield Completion(start=offset - delta,
                                  end=offset,
                                  text=jm.name_with_symbols,
                                  type=type_,
                                  signature=signature,
                                  _origin='jedi')
 
                 if time.monotonic() > deadline:
                     break
 
         for jm in iter_jm:
             delta = len(jm.name_with_symbols) - len(jm.complete)
             yield Completion(
                 start=offset - delta,
                 end=offset,
                 text=jm.name_with_symbols,
                 type=_UNKNOWN_TYPE,  # don't compute type for speed
                 _origin="jedi",
                 signature="",
             )
 
         # TODO:
         # Suppress this, right now just for debug.
         if jedi_matches and non_jedi_results and self.debug:
             some_start_offset = before.rfind(
                 next(iter(non_jedi_results.values()))["matched_fragment"]
             )
             yield Completion(
                 start=some_start_offset,
                 end=offset,
                 text="--jedi/ipython--",
                 _origin="debug",
                 type="none",
                 signature="",
             )
 
         ordered: List[Completion] = []
         sortable: List[Completion] = []
 
         for origin, result in non_jedi_results.items():
             matched_text = result["matched_fragment"]
             start_offset = before.rfind(matched_text)
             is_ordered = result.get("ordered", False)
             container = ordered if is_ordered else sortable
 
             # I'm unsure if this is always true, so let's assert and see if it
             # crash
             assert before.endswith(matched_text)
 
             for simple_completion in result["completions"]:
                 completion = Completion(
                     start=start_offset,
                     end=offset,
                     text=simple_completion.text,
                     _origin=origin,
                     signature="",
                     type=simple_completion.type or _UNKNOWN_TYPE,
                 )
                 container.append(completion)
 
         yield from list(self._deduplicate(ordered + self._sort(sortable)))[
             :MATCHES_LIMIT
         ]
 
     def complete(self, text=None, line_buffer=None, cursor_pos=None) -> Tuple[str, Sequence[str]]:
         """Find completions for the given text and line context.
 
         Note that both the text and the line_buffer are optional, but at least
         one of them must be given.
 
         Parameters
         ----------
         text : string, optional
             Text to perform the completion on.  If not given, the line buffer
             is split using the instance's CompletionSplitter object.
         line_buffer : string, optional
             If not given, the completer attempts to obtain the current line
             buffer via readline.  This keyword allows clients which are
             requesting for text completions in non-readline contexts to inform
             the completer of the entire text.
         cursor_pos : int, optional
             Index of the cursor in the full line buffer.  Should be provided by
             remote frontends where kernel has no access to frontend state.
 
         Returns
         -------
         Tuple of two items:
         text : str
             Text that was actually used in the completion.
         matches : list
             A list of completion matches.
 
         Notes
         -----
             This API is likely to be deprecated and replaced by
             :any:`IPCompleter.completions` in the future.
 
         """
         warnings.warn('`Completer.complete` is pending deprecation since '
                 'IPython 6.0 and will be replaced by `Completer.completions`.',
                       PendingDeprecationWarning)
         # potential todo, FOLD the 3rd throw away argument of _complete
         # into the first 2 one.
         # TODO: Q: does the above refer to jedi completions (i.e. 0-indexed?)
         # TODO: should we deprecate now, or does it stay?
 
         results = self._complete(
             line_buffer=line_buffer, cursor_pos=cursor_pos, text=text, cursor_line=0
         )
 
         jedi_matcher_id = _get_matcher_id(self._jedi_matcher)
 
         return self._arrange_and_extract(
             results,
             # TODO: can we confirm that excluding Jedi here was a deliberate choice in previous version?
             skip_matchers={jedi_matcher_id},
             # this API does not support different start/end positions (fragments of token).
             abort_if_offset_changes=True,
         )
 
     def _arrange_and_extract(
         self,
         results: Dict[str, MatcherResult],
         skip_matchers: Set[str],
         abort_if_offset_changes: bool,
     ):
         sortable: List[AnyMatcherCompletion] = []
         ordered: List[AnyMatcherCompletion] = []
         most_recent_fragment = None
         for identifier, result in results.items():
             if identifier in skip_matchers:
                 continue
             if not result["completions"]:
                 continue
             if not most_recent_fragment:
                 most_recent_fragment = result["matched_fragment"]
             if (
                 abort_if_offset_changes
                 and result["matched_fragment"] != most_recent_fragment
             ):
                 break
             if result.get("ordered", False):
                 ordered.extend(result["completions"])
             else:
                 sortable.extend(result["completions"])
 
         if not most_recent_fragment:
             most_recent_fragment = ""  # to satisfy typechecker (and just in case)
 
         return most_recent_fragment, [
             m.text for m in self._deduplicate(ordered + self._sort(sortable))
         ]
 
     def _complete(self, *, cursor_line, cursor_pos, line_buffer=None, text=None,
                   full_text=None) -> _CompleteResult:
         """
         Like complete but can also returns raw jedi completions as well as the
         origin of the completion text. This could (and should) be made much
         cleaner but that will be simpler once we drop the old (and stateful)
         :any:`complete` API.
 
         With current provisional API, cursor_pos act both (depending on the
         caller) as the offset in the ``text`` or ``line_buffer``, or as the
         ``column`` when passing multiline strings this could/should be renamed
         but would add extra noise.
 
         Parameters
         ----------
         cursor_line
             Index of the line the cursor is on. 0 indexed.
         cursor_pos
             Position of the cursor in the current line/line_buffer/text. 0
             indexed.
         line_buffer : optional, str
             The current line the cursor is in, this is mostly due to legacy
             reason that readline could only give a us the single current line.
             Prefer `full_text`.
         text : str
             The current "token" the cursor is in, mostly also for historical
             reasons. as the completer would trigger only after the current line
             was parsed.
         full_text : str
             Full text of the current cell.
 
         Returns
         -------
         An ordered dictionary where keys are identifiers of completion
         matchers and values are ``MatcherResult``s.
         """
 
         # if the cursor position isn't given, the only sane assumption we can
         # make is that it's at the end of the line (the common case)
         if cursor_pos is None:
             cursor_pos = len(line_buffer) if text is None else len(text)
 
         if self.use_main_ns:
             self.namespace = __main__.__dict__
 
         # if text is either None or an empty string, rely on the line buffer
         if (not line_buffer) and full_text:
             line_buffer = full_text.split('\n')[cursor_line]
         if not text:  # issue #11508: check line_buffer before calling split_line
             text = (
                 self.splitter.split_line(line_buffer, cursor_pos) if line_buffer else ""
             )
 
         # If no line buffer is given, assume the input text is all there was
         if line_buffer is None:
             line_buffer = text
 
         # deprecated - do not use `line_buffer` in new code.
         self.line_buffer = line_buffer
         self.text_until_cursor = self.line_buffer[:cursor_pos]
 
         if not full_text:
             full_text = line_buffer
 
         context = CompletionContext(
             full_text=full_text,
             cursor_position=cursor_pos,
             cursor_line=cursor_line,
             token=text,
             limit=MATCHES_LIMIT,
         )
 
         # Start with a clean slate of completions
         results: Dict[str, MatcherResult] = {}
 
         jedi_matcher_id = _get_matcher_id(self._jedi_matcher)
 
         suppressed_matchers: Set[str] = set()
 
         matchers = {
             _get_matcher_id(matcher): matcher
             for matcher in sorted(
                 self.matchers, key=_get_matcher_priority, reverse=True
             )
         }
 
         for matcher_id, matcher in matchers.items():
             matcher_id = _get_matcher_id(matcher)
 
             if matcher_id in self.disable_matchers:
                 continue
 
             if matcher_id in results:
                 warnings.warn(f"Duplicate matcher ID: {matcher_id}.")
 
             if matcher_id in suppressed_matchers:
                 continue
 
             result: MatcherResult
             try:
                 if _is_matcher_v1(matcher):
                     result = _convert_matcher_v1_result_to_v2(
                         matcher(text), type=_UNKNOWN_TYPE
                     )
                 elif _is_matcher_v2(matcher):
                     result = matcher(context)
                 else:
                     api_version = _get_matcher_api_version(matcher)
                     raise ValueError(f"Unsupported API version {api_version}")
             except:
                 # Show the ugly traceback if the matcher causes an
                 # exception, but do NOT crash the kernel!
                 sys.excepthook(*sys.exc_info())
                 continue
 
             # set default value for matched fragment if suffix was not selected.
             result["matched_fragment"] = result.get("matched_fragment", context.token)
 
             if not suppressed_matchers:
                 suppression_recommended: Union[bool, Set[str]] = result.get(
                     "suppress", False
                 )
 
                 suppression_config = (
                     self.suppress_competing_matchers.get(matcher_id, None)
                     if isinstance(self.suppress_competing_matchers, dict)
                     else self.suppress_competing_matchers
                 )
                 should_suppress = (
                     (suppression_config is True)
                     or (suppression_recommended and (suppression_config is not False))
                 ) and has_any_completions(result)
 
                 if should_suppress:
                     suppression_exceptions: Set[str] = result.get(
                         "do_not_suppress", set()
                     )
                     if isinstance(suppression_recommended, Iterable):
                         to_suppress = set(suppression_recommended)
                     else:
                         to_suppress = set(matchers)
                     suppressed_matchers = to_suppress - suppression_exceptions
 
                     new_results = {}
                     for previous_matcher_id, previous_result in results.items():
                         if previous_matcher_id not in suppressed_matchers:
                             new_results[previous_matcher_id] = previous_result
                     results = new_results
 
             results[matcher_id] = result
 
         _, matches = self._arrange_and_extract(
             results,
             # TODO Jedi completions non included in legacy stateful API; was this deliberate or omission?
             #  if it was omission, we can remove the filtering step, otherwise remove this comment.
             skip_matchers={jedi_matcher_id},
             abort_if_offset_changes=False,
         )
 
         # populate legacy stateful API
         self.matches = matches
 
         return results
 
     @staticmethod
     def _deduplicate(
         matches: Sequence[AnyCompletion],
     ) -> Iterable[AnyCompletion]:
         filtered_matches: Dict[str, AnyCompletion] = {}
         for match in matches:
             text = match.text
             if (
                 text not in filtered_matches
                 or filtered_matches[text].type == _UNKNOWN_TYPE
             ):
                 filtered_matches[text] = match
 
         return filtered_matches.values()
 
     @staticmethod
     def _sort(matches: Sequence[AnyCompletion]):
         return sorted(matches, key=lambda x: completions_sorting_key(x.text))
 
     @context_matcher()
     def fwd_unicode_matcher(self, context: CompletionContext):
         """Same as :any:`fwd_unicode_match`, but adopted to new Matcher API."""
         # TODO: use `context.limit` to terminate early once we matched the maximum
         #  number that will be used downstream; can be added as an optional to
         #  `fwd_unicode_match(text: str, limit: int = None)` or we could re-implement here.
         fragment, matches = self.fwd_unicode_match(context.text_until_cursor)
         return _convert_matcher_v1_result_to_v2(
             matches, type="unicode", fragment=fragment, suppress_if_matches=True
         )
 
     def fwd_unicode_match(self, text: str) -> Tuple[str, Sequence[str]]:
         """
         Forward match a string starting with a backslash with a list of
         potential Unicode completions.
 
         Will compute list of Unicode character names on first call and cache it.
 
         .. deprecated:: 8.6
             You can use :meth:`fwd_unicode_matcher` instead.
 
         Returns
         -------
         At tuple with:
             - matched text (empty if no matches)
             - list of potential completions, empty tuple  otherwise)
         """
         # TODO: self.unicode_names is here a list we traverse each time with ~100k elements.
         # We could do a faster match using a Trie.
 
         # Using pygtrie the following seem to work:
 
         #     s = PrefixSet()
 
         #     for c in range(0,0x10FFFF + 1):
         #         try:
         #             s.add(unicodedata.name(chr(c)))
         #         except ValueError:
         #             pass
         #     [''.join(k) for k in s.iter(prefix)]
 
         # But need to be timed and adds an extra dependency.
 
         slashpos = text.rfind('\\')
         # if text starts with slash
         if slashpos > -1:
             # PERF: It's important that we don't access self._unicode_names
             # until we're inside this if-block. _unicode_names is lazily
             # initialized, and it takes a user-noticeable amount of time to
             # initialize it, so we don't want to initialize it unless we're
             # actually going to use it.
             s = text[slashpos + 1 :]
             sup = s.upper()
             candidates = [x for x in self.unicode_names if x.startswith(sup)]
             if candidates:
                 return s, candidates
             candidates = [x for x in self.unicode_names if sup in x]
             if candidates:
                 return s, candidates
             splitsup = sup.split(" ")
             candidates = [
                 x for x in self.unicode_names if all(u in x for u in splitsup)
             ]
             if candidates:
                 return s, candidates
 
             return "", ()
 
         # if text does not start with slash
         else:
             return '', ()
 
     @property
     def unicode_names(self) -> List[str]:
         """List of names of unicode code points that can be completed.
 
         The list is lazily initialized on first access.
         """
         if self._unicode_names is None:
             names = []
             for c in range(0,0x10FFFF + 1):
                 try:
                     names.append(unicodedata.name(chr(c)))
                 except ValueError:
                     pass
             self._unicode_names = _unicode_name_compute(_UNICODE_RANGES)
 
         return self._unicode_names
 
 def _unicode_name_compute(ranges:List[Tuple[int,int]]) -> List[str]:
     names = []
     for start,stop in ranges:
         for c in range(start, stop) :
             try:
                 names.append(unicodedata.name(chr(c)))
             except ValueError:
                 pass
     return names

IPython/core/formatters.py

@@ -1,1031 +1,1031 b''
 # -*- coding: utf-8 -*-
 """Display formatters.
 
 Inheritance diagram:
 
 .. inheritance-diagram:: IPython.core.formatters
    :parts: 3
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import abc
 import sys
 import traceback
 import warnings
 from io import StringIO
 
 from decorator import decorator
 
 from traitlets.config.configurable import Configurable
 from .getipython import get_ipython
 from ..utils.sentinel import Sentinel
 from ..utils.dir2 import get_real_method
 from ..lib import pretty
 from traitlets import (
     Bool, Dict, Integer, Unicode, CUnicode, ObjectName, List,
     ForwardDeclaredInstance,
     default, observe,
 )
 
 from typing import Any
 
 
 class DisplayFormatter(Configurable):
 
     active_types = List(Unicode(),
         help="""List of currently active mime-types to display.
         You can use this to set a white-list for formats to display.
         
         Most users will not need to change this value.
         """).tag(config=True)
 
     @default('active_types')
     def _active_types_default(self):
         return self.format_types
 
     @observe('active_types')
     def _active_types_changed(self, change):
         for key, formatter in self.formatters.items():
             if key in change['new']:
                 formatter.enabled = True
             else:
                 formatter.enabled = False
 
-    ipython_display_formatter = ForwardDeclaredInstance("FormatterABC")
+    ipython_display_formatter = ForwardDeclaredInstance("FormatterABC")  # type: ignore
 
     @default("ipython_display_formatter")
     def _default_formatter(self):
         return IPythonDisplayFormatter(parent=self)
 
-    mimebundle_formatter = ForwardDeclaredInstance("FormatterABC")
+    mimebundle_formatter = ForwardDeclaredInstance("FormatterABC")  # type: ignore
 
     @default("mimebundle_formatter")
     def _default_mime_formatter(self):
         return MimeBundleFormatter(parent=self)
 
     # A dict of formatter whose keys are format types (MIME types) and whose
     # values are subclasses of BaseFormatter.
     formatters = Dict()
 
     @default("formatters")
     def _formatters_default(self):
         """Activate the default formatters."""
         formatter_classes = [
             PlainTextFormatter,
             HTMLFormatter,
             MarkdownFormatter,
             SVGFormatter,
             PNGFormatter,
             PDFFormatter,
             JPEGFormatter,
             LatexFormatter,
             JSONFormatter,
             JavascriptFormatter
         ]
         d = {}
         for cls in formatter_classes:
             f = cls(parent=self)
             d[f.format_type] = f
         return d
 
     def format(self, obj, include=None, exclude=None):
         """Return a format data dict for an object.
 
         By default all format types will be computed.
 
         The following MIME types are usually implemented:
 
         * text/plain
         * text/html
         * text/markdown
         * text/latex
         * application/json
         * application/javascript
         * application/pdf
         * image/png
         * image/jpeg
         * image/svg+xml
 
         Parameters
         ----------
         obj : object
             The Python object whose format data will be computed.
         include : list, tuple or set; optional
             A list of format type strings (MIME types) to include in the
             format data dict. If this is set *only* the format types included
             in this list will be computed.
         exclude : list, tuple or set; optional
             A list of format type string (MIME types) to exclude in the format
             data dict. If this is set all format types will be computed,
             except for those included in this argument.
             Mimetypes present in exclude will take precedence over the ones in include
 
         Returns
         -------
         (format_dict, metadata_dict) : tuple of two dicts
             format_dict is a dictionary of key/value pairs, one of each format that was
             generated for the object. The keys are the format types, which
             will usually be MIME type strings and the values and JSON'able
             data structure containing the raw data for the representation in
             that format.
 
             metadata_dict is a dictionary of metadata about each mime-type output.
             Its keys will be a strict subset of the keys in format_dict.
 
         Notes
         -----
             If an object implement `_repr_mimebundle_` as well as various
             `_repr_*_`, the data returned by `_repr_mimebundle_` will take
             precedence and the corresponding `_repr_*_` for this mimetype will
             not be called.
 
         """
         format_dict = {}
         md_dict = {}
         
         if self.ipython_display_formatter(obj):
             # object handled itself, don't proceed
             return {}, {}
 
         format_dict, md_dict = self.mimebundle_formatter(obj, include=include, exclude=exclude)
 
         if format_dict or md_dict:
             if include:
                 format_dict = {k:v for k,v in format_dict.items() if k in include}
                 md_dict = {k:v for k,v in md_dict.items() if k in include}
             if exclude:
                 format_dict = {k:v for k,v in format_dict.items() if k not in exclude}
                 md_dict = {k:v for k,v in md_dict.items() if k not in exclude}
 
         for format_type, formatter in self.formatters.items():
             if format_type in format_dict:
                 # already got it from mimebundle, maybe don't render again.
                 # exception: manually registered per-mime renderer
                 # check priority:
                 # 1. user-registered per-mime formatter
                 # 2. mime-bundle (user-registered or repr method)
                 # 3. default per-mime formatter (e.g. repr method)
                 try:
                     formatter.lookup(obj)
                 except KeyError:
                     # no special formatter, use mime-bundle-provided value
                     continue
             if include and format_type not in include:
                 continue
             if exclude and format_type in exclude:
                 continue
             
             md = None
             try:
                 data = formatter(obj)
             except:
                 # FIXME: log the exception
                 raise
             
             # formatters can return raw data or (data, metadata)
             if isinstance(data, tuple) and len(data) == 2:
                 data, md = data
             
             if data is not None:
                 format_dict[format_type] = data
             if md is not None:
                 md_dict[format_type] = md
         return format_dict, md_dict
 
     @property
     def format_types(self):
         """Return the format types (MIME types) of the active formatters."""
         return list(self.formatters.keys())
 
 
 #-----------------------------------------------------------------------------
 # Formatters for specific format types (text, html, svg, etc.)
 #-----------------------------------------------------------------------------
 
 
 def _safe_repr(obj):
     """Try to return a repr of an object
 
     always returns a string, at least.
     """
     try:
         return repr(obj)
     except Exception as e:
         return "un-repr-able object (%r)" % e
 
 
 class FormatterWarning(UserWarning):
     """Warning class for errors in formatters"""
 
 @decorator
 def catch_format_error(method, self, *args, **kwargs):
     """show traceback on failed format call"""
     try:
         r = method(self, *args, **kwargs)
     except NotImplementedError:
         # don't warn on NotImplementedErrors
         return self._check_return(None, args[0])
     except Exception:
         exc_info = sys.exc_info()
         ip = get_ipython()
         if ip is not None:
             ip.showtraceback(exc_info)
         else:
             traceback.print_exception(*exc_info)
         return self._check_return(None, args[0])
     return self._check_return(r, args[0])
 
 
 class FormatterABC(metaclass=abc.ABCMeta):
     """ Abstract base class for Formatters.
 
     A formatter is a callable class that is responsible for computing the
     raw format data for a particular format type (MIME type). For example,
     an HTML formatter would have a format type of `text/html` and would return
     the HTML representation of the object when called.
     """
 
     # The format type of the data returned, usually a MIME type.
     format_type = 'text/plain'
 
     # Is the formatter enabled...
     enabled = True
     
     @abc.abstractmethod
     def __call__(self, obj):
         """Return a JSON'able representation of the object.
 
         If the object cannot be formatted by this formatter,
         warn and return None.
         """
         return repr(obj)
 
 
 def _mod_name_key(typ):
     """Return a (__module__, __name__) tuple for a type.
 
     Used as key in Formatter.deferred_printers.
     """
     module = getattr(typ, '__module__', None)
     name = getattr(typ, '__name__', None)
     return (module, name)
 
 
 def _get_type(obj):
     """Return the type of an instance (old and new-style)"""
     return getattr(obj, '__class__', None) or type(obj)
 
 
 _raise_key_error = Sentinel('_raise_key_error', __name__, 
 """
 Special value to raise a KeyError
 
 Raise KeyError in `BaseFormatter.pop` if passed as the default value to `pop`
 """)
 
 
 class BaseFormatter(Configurable):
     """A base formatter class that is configurable.
 
     This formatter should usually be used as the base class of all formatters.
     It is a traited :class:`Configurable` class and includes an extensible
     API for users to determine how their objects are formatted. The following
     logic is used to find a function to format an given object.
 
     1. The object is introspected to see if it has a method with the name
        :attr:`print_method`. If is does, that object is passed to that method
        for formatting.
     2. If no print method is found, three internal dictionaries are consulted
        to find print method: :attr:`singleton_printers`, :attr:`type_printers`
        and :attr:`deferred_printers`.
 
     Users should use these dictionaries to register functions that will be
     used to compute the format data for their objects (if those objects don't
     have the special print methods). The easiest way of using these
     dictionaries is through the :meth:`for_type` and :meth:`for_type_by_name`
     methods.
 
     If no function/callable is found to compute the format data, ``None`` is
     returned and this format type is not used.
     """
 
     format_type = Unicode("text/plain")
     _return_type: Any = str
 
     enabled = Bool(True).tag(config=True)
 
     print_method = ObjectName('__repr__')
 
     # The singleton printers.
     # Maps the IDs of the builtin singleton objects to the format functions.
     singleton_printers = Dict().tag(config=True)
 
     # The type-specific printers.
     # Map type objects to the format functions.
     type_printers = Dict().tag(config=True)
 
     # The deferred-import type-specific printers.
     # Map (modulename, classname) pairs to the format functions.
     deferred_printers = Dict().tag(config=True)
     
     @catch_format_error
     def __call__(self, obj):
         """Compute the format for an object."""
         if self.enabled:
             # lookup registered printer
             try:
                 printer = self.lookup(obj)
             except KeyError:
                 pass
             else:
                 return printer(obj)
             # Finally look for special method names
             method = get_real_method(obj, self.print_method)
             if method is not None:
                 return method()
             return None
         else:
             return None
     
     def __contains__(self, typ):
         """map in to lookup_by_type"""
         try:
             self.lookup_by_type(typ)
         except KeyError:
             return False
         else:
             return True
     
     def _check_return(self, r, obj):
         """Check that a return value is appropriate
 
         Return the value if so, None otherwise, warning if invalid.
         """
         if r is None or isinstance(r, self._return_type) or \
             (isinstance(r, tuple) and r and isinstance(r[0], self._return_type)):
             return r
         else:
             warnings.warn(
                 "%s formatter returned invalid type %s (expected %s) for object: %s" % \
                 (self.format_type, type(r), self._return_type, _safe_repr(obj)),
                 FormatterWarning
             )
     
     def lookup(self, obj):
         """Look up the formatter for a given instance.
 
         Parameters
         ----------
         obj : object instance
 
         Returns
         -------
         f : callable
             The registered formatting callable for the type.
 
         Raises
         ------
         KeyError if the type has not been registered.
         """
         # look for singleton first
         obj_id = id(obj)
         if obj_id in self.singleton_printers:
             return self.singleton_printers[obj_id]
         # then lookup by type
         return self.lookup_by_type(_get_type(obj))
     
     def lookup_by_type(self, typ):
         """Look up the registered formatter for a type.
 
         Parameters
         ----------
         typ : type or '__module__.__name__' string for a type
 
         Returns
         -------
         f : callable
             The registered formatting callable for the type.
 
         Raises
         ------
         KeyError if the type has not been registered.
         """
         if isinstance(typ, str):
             typ_key = tuple(typ.rsplit('.',1))
             if typ_key not in self.deferred_printers:
                 # We may have it cached in the type map. We will have to
                 # iterate over all of the types to check.
                 for cls in self.type_printers:
                     if _mod_name_key(cls) == typ_key:
                         return self.type_printers[cls]
             else:
                 return self.deferred_printers[typ_key]
         else:
             for cls in pretty._get_mro(typ):
                 if cls in self.type_printers or self._in_deferred_types(cls):
                     return self.type_printers[cls]
         
         # If we have reached here, the lookup failed.
         raise KeyError("No registered printer for {0!r}".format(typ))
 
     def for_type(self, typ, func=None):
         """Add a format function for a given type.
 
         Parameters
         ----------
         typ : type or '__module__.__name__' string for a type
             The class of the object that will be formatted using `func`.
 
         func : callable
             A callable for computing the format data.
             `func` will be called with the object to be formatted,
             and will return the raw data in this formatter's format.
             Subclasses may use a different call signature for the
             `func` argument.
 
             If `func` is None or not specified, there will be no change,
             only returning the current value.
 
         Returns
         -------
         oldfunc : callable
             The currently registered callable.
             If you are registering a new formatter,
             this will be the previous value (to enable restoring later).
         """
         # if string given, interpret as 'pkg.module.class_name'
         if isinstance(typ, str):
             type_module, type_name = typ.rsplit('.', 1)
             return self.for_type_by_name(type_module, type_name, func)
         
         try:
             oldfunc = self.lookup_by_type(typ)
         except KeyError:
             oldfunc = None
         
         if func is not None:
             self.type_printers[typ] = func
         
         return oldfunc
 
     def for_type_by_name(self, type_module, type_name, func=None):
         """Add a format function for a type specified by the full dotted
         module and name of the type, rather than the type of the object.
 
         Parameters
         ----------
         type_module : str
             The full dotted name of the module the type is defined in, like
             ``numpy``.
 
         type_name : str
             The name of the type (the class name), like ``dtype``
 
         func : callable
             A callable for computing the format data.
             `func` will be called with the object to be formatted,
             and will return the raw data in this formatter's format.
             Subclasses may use a different call signature for the
             `func` argument.
 
             If `func` is None or unspecified, there will be no change,
             only returning the current value.
 
         Returns
         -------
         oldfunc : callable
             The currently registered callable.
             If you are registering a new formatter,
             this will be the previous value (to enable restoring later).
         """
         key = (type_module, type_name)
         
         try:
             oldfunc = self.lookup_by_type("%s.%s" % key)
         except KeyError:
             oldfunc = None
         
         if func is not None:
             self.deferred_printers[key] = func
         return oldfunc
     
     def pop(self, typ, default=_raise_key_error):
         """Pop a formatter for the given type.
 
         Parameters
         ----------
         typ : type or '__module__.__name__' string for a type
         default : object
             value to be returned if no formatter is registered for typ.
 
         Returns
         -------
         obj : object
             The last registered object for the type.
 
         Raises
         ------
         KeyError if the type is not registered and default is not specified.
         """
         
         if isinstance(typ, str):
             typ_key = tuple(typ.rsplit('.',1))
             if typ_key not in self.deferred_printers:
                 # We may have it cached in the type map. We will have to
                 # iterate over all of the types to check.
                 for cls in self.type_printers:
                     if _mod_name_key(cls) == typ_key:
                         old = self.type_printers.pop(cls)
                         break
                 else:
                     old = default
             else:
                 old = self.deferred_printers.pop(typ_key)
         else:
             if typ in self.type_printers:
                 old = self.type_printers.pop(typ)
             else:
                 old = self.deferred_printers.pop(_mod_name_key(typ), default)
         if old is _raise_key_error:
             raise KeyError("No registered value for {0!r}".format(typ))
         return old
 
     def _in_deferred_types(self, cls):
         """
         Check if the given class is specified in the deferred type registry.
 
         Successful matches will be moved to the regular type registry for future use.
         """
         mod = getattr(cls, '__module__', None)
         name = getattr(cls, '__name__', None)
         key = (mod, name)
         if key in self.deferred_printers:
             # Move the printer over to the regular registry.
             printer = self.deferred_printers.pop(key)
             self.type_printers[cls] = printer
             return True
         return False
 
 
 class PlainTextFormatter(BaseFormatter):
     """The default pretty-printer.
 
     This uses :mod:`IPython.lib.pretty` to compute the format data of
     the object. If the object cannot be pretty printed, :func:`repr` is used.
     See the documentation of :mod:`IPython.lib.pretty` for details on
     how to write pretty printers.  Here is a simple example::
 
         def dtype_pprinter(obj, p, cycle):
             if cycle:
                 return p.text('dtype(...)')
             if hasattr(obj, 'fields'):
                 if obj.fields is None:
                     p.text(repr(obj))
                 else:
                     p.begin_group(7, 'dtype([')
                     for i, field in enumerate(obj.descr):
                         if i > 0:
                             p.text(',')
                             p.breakable()
                         p.pretty(field)
                     p.end_group(7, '])')
     """
 
     # The format type of data returned.
     format_type = Unicode('text/plain')
 
     # This subclass ignores this attribute as it always need to return
     # something.
     enabled = Bool(True).tag(config=False)
     
     max_seq_length = Integer(pretty.MAX_SEQ_LENGTH,
         help="""Truncate large collections (lists, dicts, tuples, sets) to this size.
         
         Set to 0 to disable truncation.
         """
     ).tag(config=True)
     
     # Look for a _repr_pretty_ methods to use for pretty printing.
     print_method = ObjectName('_repr_pretty_')
 
     # Whether to pretty-print or not.
     pprint = Bool(True).tag(config=True)
 
     # Whether to be verbose or not.
     verbose = Bool(False).tag(config=True)
 
     # The maximum width.
     max_width = Integer(79).tag(config=True)
 
     # The newline character.
     newline = Unicode('\n').tag(config=True)
 
     # format-string for pprinting floats
     float_format = Unicode('%r')
     # setter for float precision, either int or direct format-string
     float_precision = CUnicode('').tag(config=True)
 
     @observe('float_precision')
     def _float_precision_changed(self, change):
         """float_precision changed, set float_format accordingly.
 
         float_precision can be set by int or str.
         This will set float_format, after interpreting input.
         If numpy has been imported, numpy print precision will also be set.
 
         integer `n` sets format to '%.nf', otherwise, format set directly.
 
         An empty string returns to defaults (repr for float, 8 for numpy).
 
         This parameter can be set via the '%precision' magic.
         """
         new = change['new']
         if '%' in new:
             # got explicit format string
             fmt = new
             try:
                 fmt%3.14159
             except Exception as e:
                 raise ValueError("Precision must be int or format string, not %r"%new) from e
         elif new:
             # otherwise, should be an int
             try:
                 i = int(new)
                 assert i >= 0
             except ValueError as e:
                 raise ValueError("Precision must be int or format string, not %r"%new) from e
             except AssertionError as e:
                 raise ValueError("int precision must be non-negative, not %r"%i) from e
 
             fmt = '%%.%if'%i
             if 'numpy' in sys.modules:
                 # set numpy precision if it has been imported
                 import numpy
                 numpy.set_printoptions(precision=i)
         else:
             # default back to repr
             fmt = '%r'
             if 'numpy' in sys.modules:
                 import numpy
                 # numpy default is 8
                 numpy.set_printoptions(precision=8)
         self.float_format = fmt
 
     # Use the default pretty printers from IPython.lib.pretty.
     @default('singleton_printers')
     def _singleton_printers_default(self):
         return pretty._singleton_pprinters.copy()
 
     @default('type_printers')
     def _type_printers_default(self):
         d = pretty._type_pprinters.copy()
         d[float] = lambda obj,p,cycle: p.text(self.float_format%obj)
         # if NumPy is used, set precision for its float64 type
         if "numpy" in sys.modules:
             import numpy
 
             d[numpy.float64] = lambda obj, p, cycle: p.text(self.float_format % obj)
         return d
 
     @default('deferred_printers')
     def _deferred_printers_default(self):
         return pretty._deferred_type_pprinters.copy()
 
     #### FormatterABC interface ####
 
     @catch_format_error
     def __call__(self, obj):
         """Compute the pretty representation of the object."""
         if not self.pprint:
             return repr(obj)
         else:
             stream = StringIO()
             printer = pretty.RepresentationPrinter(stream, self.verbose,
                 self.max_width, self.newline,
                 max_seq_length=self.max_seq_length,
                 singleton_pprinters=self.singleton_printers,
                 type_pprinters=self.type_printers,
                 deferred_pprinters=self.deferred_printers)
             printer.pretty(obj)
             printer.flush()
             return stream.getvalue()
 
 
 class HTMLFormatter(BaseFormatter):
     """An HTML formatter.
 
     To define the callables that compute the HTML representation of your
     objects, define a :meth:`_repr_html_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a valid HTML snippet that
     could be injected into an existing DOM. It should *not* include the
     ```<html>`` or ```<body>`` tags.
     """
     format_type = Unicode('text/html')
 
     print_method = ObjectName('_repr_html_')
 
 
 class MarkdownFormatter(BaseFormatter):
     """A Markdown formatter.
 
     To define the callables that compute the Markdown representation of your
     objects, define a :meth:`_repr_markdown_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a valid Markdown.
     """
     format_type = Unicode('text/markdown')
 
     print_method = ObjectName('_repr_markdown_')
 
 class SVGFormatter(BaseFormatter):
     """An SVG formatter.
 
     To define the callables that compute the SVG representation of your
     objects, define a :meth:`_repr_svg_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be valid SVG enclosed in
     ```<svg>``` tags, that could be injected into an existing DOM. It should
     *not* include the ```<html>`` or ```<body>`` tags.
     """
     format_type = Unicode('image/svg+xml')
 
     print_method = ObjectName('_repr_svg_')
 
 
 class PNGFormatter(BaseFormatter):
     """A PNG formatter.
 
     To define the callables that compute the PNG representation of your
     objects, define a :meth:`_repr_png_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be raw PNG data, *not*
     base64 encoded.
     """
     format_type = Unicode('image/png')
 
     print_method = ObjectName('_repr_png_')
     
     _return_type = (bytes, str)
 
 
 class JPEGFormatter(BaseFormatter):
     """A JPEG formatter.
 
     To define the callables that compute the JPEG representation of your
     objects, define a :meth:`_repr_jpeg_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be raw JPEG data, *not*
     base64 encoded.
     """
     format_type = Unicode('image/jpeg')
 
     print_method = ObjectName('_repr_jpeg_')
 
     _return_type = (bytes, str)
 
 
 class LatexFormatter(BaseFormatter):
     """A LaTeX formatter.
 
     To define the callables that compute the LaTeX representation of your
     objects, define a :meth:`_repr_latex_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a valid LaTeX equation,
     enclosed in either ```$```, ```$$``` or another LaTeX equation
     environment.
     """
     format_type = Unicode('text/latex')
 
     print_method = ObjectName('_repr_latex_')
 
 
 class JSONFormatter(BaseFormatter):
     """A JSON string formatter.
 
     To define the callables that compute the JSONable representation of
     your objects, define a :meth:`_repr_json_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a JSONable list or dict.
     JSON scalars (None, number, string) are not allowed, only dict or list containers.
     """
     format_type = Unicode('application/json')
     _return_type = (list, dict)
 
     print_method = ObjectName('_repr_json_')
     
     def _check_return(self, r, obj):
         """Check that a return value is appropriate
 
         Return the value if so, None otherwise, warning if invalid.
         """
         if r is None:
             return
         md = None
         if isinstance(r, tuple):
             # unpack data, metadata tuple for type checking on first element
             r, md = r
 
         assert not isinstance(
             r, str
         ), "JSON-as-string has been deprecated since IPython < 3"
 
         if md is not None:
             # put the tuple back together
             r = (r, md)
         return super(JSONFormatter, self)._check_return(r, obj)
 
 
 class JavascriptFormatter(BaseFormatter):
     """A Javascript formatter.
 
     To define the callables that compute the Javascript representation of
     your objects, define a :meth:`_repr_javascript_` method or use the
     :meth:`for_type` or :meth:`for_type_by_name` methods to register functions
     that handle this.
 
     The return value of this formatter should be valid Javascript code and
     should *not* be enclosed in ```<script>``` tags.
     """
     format_type = Unicode('application/javascript')
 
     print_method = ObjectName('_repr_javascript_')
 
 
 class PDFFormatter(BaseFormatter):
     """A PDF formatter.
 
     To define the callables that compute the PDF representation of your
     objects, define a :meth:`_repr_pdf_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be raw PDF data, *not*
     base64 encoded.
     """
     format_type = Unicode('application/pdf')
 
     print_method = ObjectName('_repr_pdf_')
 
     _return_type = (bytes, str)
 
 class IPythonDisplayFormatter(BaseFormatter):
     """An escape-hatch Formatter for objects that know how to display themselves.
     
     To define the callables that compute the representation of your
     objects, define a :meth:`_ipython_display_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this. Unlike mime-type displays, this method should not return anything,
     instead calling any appropriate display methods itself.
     
     This display formatter has highest priority.
     If it fires, no other display formatter will be called.
 
     Prior to IPython 6.1, `_ipython_display_` was the only way to display custom mime-types
     without registering a new Formatter.
     
     IPython 6.1 introduces `_repr_mimebundle_` for displaying custom mime-types,
     so `_ipython_display_` should only be used for objects that require unusual
     display patterns, such as multiple display calls.
     """
     print_method = ObjectName('_ipython_display_')
     _return_type = (type(None), bool)
 
     @catch_format_error
     def __call__(self, obj):
         """Compute the format for an object."""
         if self.enabled:
             # lookup registered printer
             try:
                 printer = self.lookup(obj)
             except KeyError:
                 pass
             else:
                 printer(obj)
                 return True
             # Finally look for special method names
             method = get_real_method(obj, self.print_method)
             if method is not None:
                 method()
                 return True
 
 
 class MimeBundleFormatter(BaseFormatter):
     """A Formatter for arbitrary mime-types.
 
     Unlike other `_repr_<mimetype>_` methods,
     `_repr_mimebundle_` should return mime-bundle data,
     either the mime-keyed `data` dictionary or the tuple `(data, metadata)`.
     Any mime-type is valid.
 
     To define the callables that compute the mime-bundle representation of your
     objects, define a :meth:`_repr_mimebundle_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     .. versionadded:: 6.1
     """
     print_method = ObjectName('_repr_mimebundle_')
     _return_type = dict
     
     def _check_return(self, r, obj):
         r = super(MimeBundleFormatter, self)._check_return(r, obj)
         # always return (data, metadata):
         if r is None:
             return {}, {}
         if not isinstance(r, tuple):
             return r, {}
         return r
 
     @catch_format_error
     def __call__(self, obj, include=None, exclude=None):
         """Compute the format for an object.
 
         Identical to parent's method but we pass extra parameters to the method.
 
         Unlike other _repr_*_ `_repr_mimebundle_` should allow extra kwargs, in
         particular `include` and `exclude`.
         """
         if self.enabled:
             # lookup registered printer
             try:
                 printer = self.lookup(obj)
             except KeyError:
                 pass
             else:
                 return printer(obj)
             # Finally look for special method names
             method = get_real_method(obj, self.print_method)
 
             if method is not None:
                 return method(include=include, exclude=exclude)
             return None
         else:
             return None
 
 
 FormatterABC.register(BaseFormatter)
 FormatterABC.register(PlainTextFormatter)
 FormatterABC.register(HTMLFormatter)
 FormatterABC.register(MarkdownFormatter)
 FormatterABC.register(SVGFormatter)
 FormatterABC.register(PNGFormatter)
 FormatterABC.register(PDFFormatter)
 FormatterABC.register(JPEGFormatter)
 FormatterABC.register(LatexFormatter)
 FormatterABC.register(JSONFormatter)
 FormatterABC.register(JavascriptFormatter)
 FormatterABC.register(IPythonDisplayFormatter)
 FormatterABC.register(MimeBundleFormatter)
 
 
 def format_display_data(obj, include=None, exclude=None):
     """Return a format data dict for an object.
 
     By default all format types will be computed.
 
     Parameters
     ----------
     obj : object
         The Python object whose format data will be computed.
 
     Returns
     -------
     format_dict : dict
         A dictionary of key/value pairs, one or each format that was
         generated for the object. The keys are the format types, which
         will usually be MIME type strings and the values and JSON'able
         data structure containing the raw data for the representation in
         that format.
     include : list or tuple, optional
         A list of format type strings (MIME types) to include in the
         format data dict. If this is set *only* the format types included
         in this list will be computed.
     exclude : list or tuple, optional
         A list of format type string (MIME types) to exclude in the format
         data dict. If this is set all format types will be computed,
         except for those included in this argument.
     """
     from .interactiveshell import InteractiveShell
 
     return InteractiveShell.instance().display_formatter.format(
         obj,
         include,
         exclude
     )

IPython/core/history.py

@@ -1,978 +1,979 b''
 """ History related magics and functionality """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 
 import atexit
 import datetime
 from pathlib import Path
 import re
 import sqlite3
 import threading
 
 from traitlets.config.configurable import LoggingConfigurable
 from decorator import decorator
 from IPython.utils.decorators import undoc
 from IPython.paths import locate_profile
 from traitlets import (
     Any,
     Bool,
     Dict,
     Instance,
     Integer,
     List,
     Unicode,
     Union,
     TraitError,
     default,
     observe,
 )
 
 #-----------------------------------------------------------------------------
 # Classes and functions
 #-----------------------------------------------------------------------------
 
 @undoc
 class DummyDB(object):
     """Dummy DB that will act as a black hole for history.
 
     Only used in the absence of sqlite"""
     def execute(*args, **kwargs):
         return []
 
     def commit(self, *args, **kwargs):
         pass
 
     def __enter__(self, *args, **kwargs):
         pass
 
     def __exit__(self, *args, **kwargs):
         pass
 
 
 @decorator
 def only_when_enabled(f, self, *a, **kw):
     """Decorator: return an empty list in the absence of sqlite."""
     if not self.enabled:
         return []
     else:
         return f(self, *a, **kw)
 
 
 # use 16kB as threshold for whether a corrupt history db should be saved
 # that should be at least 100 entries or so
 _SAVE_DB_SIZE = 16384
 
 @decorator
 def catch_corrupt_db(f, self, *a, **kw):
     """A decorator which wraps HistoryAccessor method calls to catch errors from
     a corrupt SQLite database, move the old database out of the way, and create
     a new one.
 
     We avoid clobbering larger databases because this may be triggered due to filesystem issues,
     not just a corrupt file.
     """
     try:
         return f(self, *a, **kw)
     except (sqlite3.DatabaseError, sqlite3.OperationalError) as e:
         self._corrupt_db_counter += 1
         self.log.error("Failed to open SQLite history %s (%s).", self.hist_file, e)
         if self.hist_file != ':memory:':
             if self._corrupt_db_counter > self._corrupt_db_limit:
                 self.hist_file = ':memory:'
                 self.log.error("Failed to load history too many times, history will not be saved.")
             elif self.hist_file.is_file():
                 # move the file out of the way
                 base = str(self.hist_file.parent / self.hist_file.stem)
                 ext = self.hist_file.suffix
                 size = self.hist_file.stat().st_size
                 if size >= _SAVE_DB_SIZE:
                     # if there's significant content, avoid clobbering
                     now = datetime.datetime.now().isoformat().replace(':', '.')
                     newpath = base + '-corrupt-' + now + ext
                     # don't clobber previous corrupt backups
                     for i in range(100):
                         if not Path(newpath).exists():
                             break
                         else:
                             newpath = base + '-corrupt-' + now + (u'-%i' % i) + ext
                 else:
                     # not much content, possibly empty; don't worry about clobbering
                     # maybe we should just delete it?
                     newpath = base + '-corrupt' + ext
                 self.hist_file.rename(newpath)
                 self.log.error("History file was moved to %s and a new file created.", newpath)
             self.init_db()
             return []
         else:
             # Failed with :memory:, something serious is wrong
             raise
 
 
 class HistoryAccessorBase(LoggingConfigurable):
     """An abstract class for History Accessors """
 
     def get_tail(self, n=10, raw=True, output=False, include_latest=False):
         raise NotImplementedError
 
     def search(self, pattern="*", raw=True, search_raw=True,
                output=False, n=None, unique=False):
         raise NotImplementedError
 
     def get_range(self, session, start=1, stop=None, raw=True,output=False):
         raise NotImplementedError
 
     def get_range_by_str(self, rangestr, raw=True, output=False):
         raise NotImplementedError
 
 
 class HistoryAccessor(HistoryAccessorBase):
     """Access the history database without adding to it.
 
     This is intended for use by standalone history tools. IPython shells use
     HistoryManager, below, which is a subclass of this."""
 
     # counter for init_db retries, so we don't keep trying over and over
     _corrupt_db_counter = 0
      # after two failures, fallback on :memory:
     _corrupt_db_limit = 2
 
     # String holding the path to the history file
     hist_file = Union(
         [Instance(Path), Unicode()],
         help="""Path to file to use for SQLite history database.
 
         By default, IPython will put the history database in the IPython
         profile directory.  If you would rather share one history among
         profiles, you can set this value in each, so that they are consistent.
 
         Due to an issue with fcntl, SQLite is known to misbehave on some NFS
         mounts.  If you see IPython hanging, try setting this to something on a
         local disk, e.g::
 
             ipython --HistoryManager.hist_file=/tmp/ipython_hist.sqlite
 
         you can also use the specific value `:memory:` (including the colon
         at both end but not the back ticks), to avoid creating an history file.
 
         """,
     ).tag(config=True)
 
     enabled = Bool(True,
         help="""enable the SQLite history
 
         set enabled=False to disable the SQLite history,
         in which case there will be no stored history, no SQLite connection,
         and no background saving thread.  This may be necessary in some
         threaded environments where IPython is embedded.
         """,
     ).tag(config=True)
 
     connection_options = Dict(
         help="""Options for configuring the SQLite connection
 
         These options are passed as keyword args to sqlite3.connect
         when establishing database connections.
         """
     ).tag(config=True)
 
     @default("connection_options")
     def _default_connection_options(self):
         return dict(check_same_thread=False)
 
     # The SQLite database
     db = Any()
     @observe('db')
     def _db_changed(self, change):
         """validate the db, since it can be an Instance of two different types"""
         new = change['new']
         connection_types = (DummyDB, sqlite3.Connection)
         if not isinstance(new, connection_types):
             msg = "%s.db must be sqlite3 Connection or DummyDB, not %r" % \
                     (self.__class__.__name__, new)
             raise TraitError(msg)
 
     def __init__(self, profile="default", hist_file="", **traits):
         """Create a new history accessor.
 
         Parameters
         ----------
         profile : str
             The name of the profile from which to open history.
         hist_file : str
             Path to an SQLite history database stored by IPython. If specified,
             hist_file overrides profile.
         config : :class:`~traitlets.config.loader.Config`
             Config object. hist_file can also be set through this.
         """
         super(HistoryAccessor, self).__init__(**traits)
         # defer setting hist_file from kwarg until after init,
         # otherwise the default kwarg value would clobber any value
         # set by config
         if hist_file:
             self.hist_file = hist_file
 
         try:
             self.hist_file
         except TraitError:
             # No one has set the hist_file, yet.
             self.hist_file = self._get_hist_file_name(profile)
 
         self.init_db()
 
     def _get_hist_file_name(self, profile='default'):
         """Find the history file for the given profile name.
 
         This is overridden by the HistoryManager subclass, to use the shell's
         active profile.
 
         Parameters
         ----------
         profile : str
             The name of a profile which has a history file.
         """
         return Path(locate_profile(profile)) / "history.sqlite"
 
     @catch_corrupt_db
     def init_db(self):
         """Connect to the database, and create tables if necessary."""
         if not self.enabled:
             self.db = DummyDB()
             return
 
         # use detect_types so that timestamps return datetime objects
         kwargs = dict(detect_types=sqlite3.PARSE_DECLTYPES|sqlite3.PARSE_COLNAMES)
         kwargs.update(self.connection_options)
         self.db = sqlite3.connect(str(self.hist_file), **kwargs)
         with self.db:
             self.db.execute(
                 """CREATE TABLE IF NOT EXISTS sessions (session integer
                             primary key autoincrement, start timestamp,
                             end timestamp, num_cmds integer, remark text)"""
             )
             self.db.execute(
                 """CREATE TABLE IF NOT EXISTS history
                     (session integer, line integer, source text, source_raw text,
                     PRIMARY KEY (session, line))"""
             )
             # Output history is optional, but ensure the table's there so it can be
             # enabled later.
             self.db.execute(
                 """CREATE TABLE IF NOT EXISTS output_history
                             (session integer, line integer, output text,
                             PRIMARY KEY (session, line))"""
             )
         # success! reset corrupt db count
         self._corrupt_db_counter = 0
 
     def writeout_cache(self):
         """Overridden by HistoryManager to dump the cache before certain
         database lookups."""
         pass
 
     ## -------------------------------
     ## Methods for retrieving history:
     ## -------------------------------
     def _run_sql(self, sql, params, raw=True, output=False, latest=False):
         """Prepares and runs an SQL query for the history database.
 
         Parameters
         ----------
         sql : str
             Any filtering expressions to go after SELECT ... FROM ...
         params : tuple
             Parameters passed to the SQL query (to replace "?")
         raw, output : bool
             See :meth:`get_range`
         latest : bool
             Select rows with max (session, line)
 
         Returns
         -------
         Tuples as :meth:`get_range`
         """
         toget = 'source_raw' if raw else 'source'
         sqlfrom = "history"
         if output:
             sqlfrom = "history LEFT JOIN output_history USING (session, line)"
             toget = "history.%s, output_history.output" % toget
         if latest:
             toget += ", MAX(session * 128 * 1024 + line)"
         this_querry = "SELECT session, line, %s FROM %s " % (toget, sqlfrom) + sql
         cur = self.db.execute(this_querry, params)
         if latest:
             cur = (row[:-1] for row in cur)
         if output:    # Regroup into 3-tuples, and parse JSON
             return ((ses, lin, (inp, out)) for ses, lin, inp, out in cur)
         return cur
 
     @only_when_enabled
     @catch_corrupt_db
     def get_session_info(self, session):
         """Get info about a session.
 
         Parameters
         ----------
         session : int
             Session number to retrieve.
 
         Returns
         -------
         session_id : int
             Session ID number
         start : datetime
             Timestamp for the start of the session.
         end : datetime
             Timestamp for the end of the session, or None if IPython crashed.
         num_cmds : int
             Number of commands run, or None if IPython crashed.
         remark : unicode
             A manually set description.
         """
         query = "SELECT * from sessions where session == ?"
         return self.db.execute(query, (session,)).fetchone()
 
     @catch_corrupt_db
     def get_last_session_id(self):
         """Get the last session ID currently in the database.
 
         Within IPython, this should be the same as the value stored in
         :attr:`HistoryManager.session_number`.
         """
         for record in self.get_tail(n=1, include_latest=True):
             return record[0]
 
     @catch_corrupt_db
     def get_tail(self, n=10, raw=True, output=False, include_latest=False):
         """Get the last n lines from the history database.
 
         Parameters
         ----------
         n : int
             The number of lines to get
         raw, output : bool
             See :meth:`get_range`
         include_latest : bool
             If False (default), n+1 lines are fetched, and the latest one
             is discarded. This is intended to be used where the function
             is called by a user command, which it should not return.
 
         Returns
         -------
         Tuples as :meth:`get_range`
         """
         self.writeout_cache()
         if not include_latest:
             n += 1
         cur = self._run_sql(
             "ORDER BY session DESC, line DESC LIMIT ?", (n,), raw=raw, output=output
         )
         if not include_latest:
             return reversed(list(cur)[1:])
         return reversed(list(cur))
 
     @catch_corrupt_db
     def search(self, pattern="*", raw=True, search_raw=True,
                output=False, n=None, unique=False):
         """Search the database using unix glob-style matching (wildcards
         * and ?).
 
         Parameters
         ----------
         pattern : str
             The wildcarded pattern to match when searching
         search_raw : bool
             If True, search the raw input, otherwise, the parsed input
         raw, output : bool
             See :meth:`get_range`
         n : None or int
             If an integer is given, it defines the limit of
             returned entries.
         unique : bool
             When it is true, return only unique entries.
 
         Returns
         -------
         Tuples as :meth:`get_range`
         """
         tosearch = "source_raw" if search_raw else "source"
         if output:
             tosearch = "history." + tosearch
         self.writeout_cache()
         sqlform = "WHERE %s GLOB ?" % tosearch
         params = (pattern,)
         if unique:
             sqlform += ' GROUP BY {0}'.format(tosearch)
         if n is not None:
             sqlform += " ORDER BY session DESC, line DESC LIMIT ?"
             params += (n,)
         elif unique:
             sqlform += " ORDER BY session, line"
         cur = self._run_sql(sqlform, params, raw=raw, output=output, latest=unique)
         if n is not None:
             return reversed(list(cur))
         return cur
 
     @catch_corrupt_db
     def get_range(self, session, start=1, stop=None, raw=True,output=False):
         """Retrieve input by session.
 
         Parameters
         ----------
         session : int
             Session number to retrieve.
         start : int
             First line to retrieve.
         stop : int
             End of line range (excluded from output itself). If None, retrieve
             to the end of the session.
         raw : bool
             If True, return untranslated input
         output : bool
             If True, attempt to include output. This will be 'real' Python
             objects for the current session, or text reprs from previous
             sessions if db_log_output was enabled at the time. Where no output
             is found, None is used.
 
         Returns
         -------
         entries
             An iterator over the desired lines. Each line is a 3-tuple, either
             (session, line, input) if output is False, or
             (session, line, (input, output)) if output is True.
         """
         if stop:
             lineclause = "line >= ? AND line < ?"
             params = (session, start, stop)
         else:
             lineclause = "line>=?"
             params = (session, start)
 
         return self._run_sql("WHERE session==? AND %s" % lineclause,
                                     params, raw=raw, output=output)
 
     def get_range_by_str(self, rangestr, raw=True, output=False):
         """Get lines of history from a string of ranges, as used by magic
         commands %hist, %save, %macro, etc.
 
         Parameters
         ----------
         rangestr : str
             A string specifying ranges, e.g. "5 ~2/1-4". If empty string is used,
             this will return everything from current session's history.
 
             See the documentation of :func:`%history` for the full details.
 
         raw, output : bool
             As :meth:`get_range`
 
         Returns
         -------
         Tuples as :meth:`get_range`
         """
         for sess, s, e in extract_hist_ranges(rangestr):
             for line in self.get_range(sess, s, e, raw=raw, output=output):
                 yield line
 
 
 class HistoryManager(HistoryAccessor):
     """A class to organize all history-related functionality in one place.
     """
     # Public interface
 
     # An instance of the IPython shell we are attached to
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC',
                      allow_none=True)
     # Lists to hold processed and raw history. These start with a blank entry
     # so that we can index them starting from 1
     input_hist_parsed = List([""])
     input_hist_raw = List([""])
     # A list of directories visited during session
-    dir_hist = List()
-    @default('dir_hist')
+    dir_hist: List = List()
+
+    @default("dir_hist")
     def _dir_hist_default(self):
         try:
             return [Path.cwd()]
         except OSError:
             return []
 
     # A dict of output history, keyed with ints from the shell's
     # execution count.
     output_hist = Dict()
     # The text/plain repr of outputs.
     output_hist_reprs = Dict()
 
     # The number of the current session in the history database
     session_number = Integer()
 
     db_log_output = Bool(False,
         help="Should the history database include output? (default: no)"
     ).tag(config=True)
     db_cache_size = Integer(0,
         help="Write to database every x commands (higher values save disk access & power).\n"
         "Values of 1 or less effectively disable caching."
     ).tag(config=True)
     # The input and output caches
-    db_input_cache = List()
-    db_output_cache = List()
+    db_input_cache: List = List()
+    db_output_cache: List = List()
 
     # History saving in separate thread
     save_thread = Instance('IPython.core.history.HistorySavingThread',
                            allow_none=True)
     save_flag = Instance(threading.Event, allow_none=True)
 
     # Private interface
     # Variables used to store the three last inputs from the user.  On each new
     # history update, we populate the user's namespace with these, shifted as
     # necessary.
-    _i00 = Unicode(u'')
-    _i = Unicode(u'')
-    _ii = Unicode(u'')
-    _iii = Unicode(u'')
+    _i00 = Unicode("")
+    _i = Unicode("")
+    _ii = Unicode("")
+    _iii = Unicode("")
 
     # A regex matching all forms of the exit command, so that we don't store
     # them in the history (it's annoying to rewind the first entry and land on
     # an exit call).
     _exit_re = re.compile(r"(exit|quit)(\s*\(.*\))?$")
 
     def __init__(self, shell=None, config=None, **traits):
         """Create a new history manager associated with a shell instance.
         """
         super(HistoryManager, self).__init__(shell=shell, config=config,
             **traits)
         self.save_flag = threading.Event()
         self.db_input_cache_lock = threading.Lock()
         self.db_output_cache_lock = threading.Lock()
 
         try:
             self.new_session()
         except sqlite3.OperationalError:
             self.log.error("Failed to create history session in %s. History will not be saved.",
                 self.hist_file, exc_info=True)
             self.hist_file = ':memory:'
 
         if self.enabled and self.hist_file != ':memory:':
             self.save_thread = HistorySavingThread(self)
             self.save_thread.start()
 
     def _get_hist_file_name(self, profile=None):
         """Get default history file name based on the Shell's profile.
 
         The profile parameter is ignored, but must exist for compatibility with
         the parent class."""
         profile_dir = self.shell.profile_dir.location
         return Path(profile_dir) / "history.sqlite"
 
     @only_when_enabled
     def new_session(self, conn=None):
         """Get a new session number."""
         if conn is None:
             conn = self.db
 
         with conn:
             cur = conn.execute(
                 """INSERT INTO sessions VALUES (NULL, ?, NULL,
                             NULL, '') """,
                 (datetime.datetime.now().isoformat(" "),),
             )
             self.session_number = cur.lastrowid
 
     def end_session(self):
         """Close the database session, filling in the end time and line count."""
         self.writeout_cache()
         with self.db:
             self.db.execute(
                 """UPDATE sessions SET end=?, num_cmds=? WHERE
                             session==?""",
                 (
                     datetime.datetime.now().isoformat(" "),
                     len(self.input_hist_parsed) - 1,
                     self.session_number,
                 ),
             )
         self.session_number = 0
 
     def name_session(self, name):
         """Give the current session a name in the history database."""
         with self.db:
             self.db.execute("UPDATE sessions SET remark=? WHERE session==?",
                             (name, self.session_number))
 
     def reset(self, new_session=True):
         """Clear the session history, releasing all object references, and
         optionally open a new session."""
         self.output_hist.clear()
         # The directory history can't be completely empty
         self.dir_hist[:] = [Path.cwd()]
 
         if new_session:
             if self.session_number:
                 self.end_session()
             self.input_hist_parsed[:] = [""]
             self.input_hist_raw[:] = [""]
             self.new_session()
 
     # ------------------------------
     # Methods for retrieving history
     # ------------------------------
     def get_session_info(self, session=0):
         """Get info about a session.
 
         Parameters
         ----------
         session : int
             Session number to retrieve. The current session is 0, and negative
             numbers count back from current session, so -1 is the previous session.
 
         Returns
         -------
         session_id : int
             Session ID number
         start : datetime
             Timestamp for the start of the session.
         end : datetime
             Timestamp for the end of the session, or None if IPython crashed.
         num_cmds : int
             Number of commands run, or None if IPython crashed.
         remark : unicode
             A manually set description.
         """
         if session <= 0:
             session += self.session_number
 
         return super(HistoryManager, self).get_session_info(session=session)
 
     @catch_corrupt_db
     def get_tail(self, n=10, raw=True, output=False, include_latest=False):
         """Get the last n lines from the history database.
 
         Most recent entry last.
 
         Completion will be reordered so that that the last ones are when
         possible from current session.
 
         Parameters
         ----------
         n : int
             The number of lines to get
         raw, output : bool
             See :meth:`get_range`
         include_latest : bool
             If False (default), n+1 lines are fetched, and the latest one
             is discarded. This is intended to be used where the function
             is called by a user command, which it should not return.
 
         Returns
         -------
         Tuples as :meth:`get_range`
         """
         self.writeout_cache()
         if not include_latest:
             n += 1
         # cursor/line/entry
         this_cur = list(
             self._run_sql(
                 "WHERE session == ? ORDER BY line DESC LIMIT ?  ",
                 (self.session_number, n),
                 raw=raw,
                 output=output,
             )
         )
         other_cur = list(
             self._run_sql(
                 "WHERE session != ? ORDER BY session DESC, line DESC LIMIT ?",
                 (self.session_number, n),
                 raw=raw,
                 output=output,
             )
         )
 
         everything = this_cur + other_cur
 
         everything = everything[:n]
 
         if not include_latest:
             return list(everything)[:0:-1]
         return list(everything)[::-1]
 
     def _get_range_session(self, start=1, stop=None, raw=True, output=False):
         """Get input and output history from the current session. Called by
         get_range, and takes similar parameters."""
         input_hist = self.input_hist_raw if raw else self.input_hist_parsed
 
         n = len(input_hist)
         if start < 0:
             start += n
         if not stop or (stop > n):
             stop = n
         elif stop < 0:
             stop += n
 
         for i in range(start, stop):
             if output:
                 line = (input_hist[i], self.output_hist_reprs.get(i))
             else:
                 line = input_hist[i]
             yield (0, i, line)
 
     def get_range(self, session=0, start=1, stop=None, raw=True,output=False):
         """Retrieve input by session.
 
         Parameters
         ----------
         session : int
             Session number to retrieve. The current session is 0, and negative
             numbers count back from current session, so -1 is previous session.
         start : int
             First line to retrieve.
         stop : int
             End of line range (excluded from output itself). If None, retrieve
             to the end of the session.
         raw : bool
             If True, return untranslated input
         output : bool
             If True, attempt to include output. This will be 'real' Python
             objects for the current session, or text reprs from previous
             sessions if db_log_output was enabled at the time. Where no output
             is found, None is used.
 
         Returns
         -------
         entries
             An iterator over the desired lines. Each line is a 3-tuple, either
             (session, line, input) if output is False, or
             (session, line, (input, output)) if output is True.
         """
         if session <= 0:
             session += self.session_number
         if session==self.session_number:          # Current session
             return self._get_range_session(start, stop, raw, output)
         return super(HistoryManager, self).get_range(session, start, stop, raw,
                                                      output)
 
     ## ----------------------------
     ## Methods for storing history:
     ## ----------------------------
     def store_inputs(self, line_num, source, source_raw=None):
         """Store source and raw input in history and create input cache
         variables ``_i*``.
 
         Parameters
         ----------
         line_num : int
             The prompt number of this input.
         source : str
             Python input.
         source_raw : str, optional
             If given, this is the raw input without any IPython transformations
             applied to it.  If not given, ``source`` is used.
         """
         if source_raw is None:
             source_raw = source
         source = source.rstrip('\n')
         source_raw = source_raw.rstrip('\n')
 
         # do not store exit/quit commands
         if self._exit_re.match(source_raw.strip()):
             return
 
         self.input_hist_parsed.append(source)
         self.input_hist_raw.append(source_raw)
 
         with self.db_input_cache_lock:
             self.db_input_cache.append((line_num, source, source_raw))
             # Trigger to flush cache and write to DB.
             if len(self.db_input_cache) >= self.db_cache_size:
                 self.save_flag.set()
 
         # update the auto _i variables
         self._iii = self._ii
         self._ii = self._i
         self._i = self._i00
         self._i00 = source_raw
 
         # hackish access to user namespace to create _i1,_i2... dynamically
         new_i = '_i%s' % line_num
         to_main = {'_i': self._i,
                    '_ii': self._ii,
                    '_iii': self._iii,
                    new_i : self._i00 }
 
         if self.shell is not None:
             self.shell.push(to_main, interactive=False)
 
     def store_output(self, line_num):
         """If database output logging is enabled, this saves all the
         outputs from the indicated prompt number to the database. It's
         called by run_cell after code has been executed.
 
         Parameters
         ----------
         line_num : int
             The line number from which to save outputs
         """
         if (not self.db_log_output) or (line_num not in self.output_hist_reprs):
             return
         output = self.output_hist_reprs[line_num]
 
         with self.db_output_cache_lock:
             self.db_output_cache.append((line_num, output))
         if self.db_cache_size <= 1:
             self.save_flag.set()
 
     def _writeout_input_cache(self, conn):
         with conn:
             for line in self.db_input_cache:
                 conn.execute("INSERT INTO history VALUES (?, ?, ?, ?)",
                                 (self.session_number,)+line)
 
     def _writeout_output_cache(self, conn):
         with conn:
             for line in self.db_output_cache:
                 conn.execute("INSERT INTO output_history VALUES (?, ?, ?)",
                                 (self.session_number,)+line)
 
     @only_when_enabled
     def writeout_cache(self, conn=None):
         """Write any entries in the cache to the database."""
         if conn is None:
             conn = self.db
 
         with self.db_input_cache_lock:
             try:
                 self._writeout_input_cache(conn)
             except sqlite3.IntegrityError:
                 self.new_session(conn)
                 print("ERROR! Session/line number was not unique in",
                       "database. History logging moved to new session",
                                                 self.session_number)
                 try:
                     # Try writing to the new session. If this fails, don't
                     # recurse
                     self._writeout_input_cache(conn)
                 except sqlite3.IntegrityError:
                     pass
             finally:
                 self.db_input_cache = []
 
         with self.db_output_cache_lock:
             try:
                 self._writeout_output_cache(conn)
             except sqlite3.IntegrityError:
                 print("!! Session/line number for output was not unique",
                       "in database. Output will not be stored.")
             finally:
                 self.db_output_cache = []
 
 
 class HistorySavingThread(threading.Thread):
     """This thread takes care of writing history to the database, so that
     the UI isn't held up while that happens.
 
     It waits for the HistoryManager's save_flag to be set, then writes out
     the history cache. The main thread is responsible for setting the flag when
     the cache size reaches a defined threshold."""
     daemon = True
     stop_now = False
     enabled = True
     def __init__(self, history_manager):
         super(HistorySavingThread, self).__init__(name="IPythonHistorySavingThread")
         self.history_manager = history_manager
         self.enabled = history_manager.enabled
         atexit.register(self.stop)
 
     @only_when_enabled
     def run(self):
         # We need a separate db connection per thread:
         try:
             self.db = sqlite3.connect(
                 str(self.history_manager.hist_file),
                 **self.history_manager.connection_options,
             )
             while True:
                 self.history_manager.save_flag.wait()
                 if self.stop_now:
                     self.db.close()
                     return
                 self.history_manager.save_flag.clear()
                 self.history_manager.writeout_cache(self.db)
         except Exception as e:
             print(("The history saving thread hit an unexpected error (%s)."
                    "History will not be written to the database.") % repr(e))
 
     def stop(self):
         """This can be called from the main thread to safely stop this thread.
 
         Note that it does not attempt to write out remaining history before
         exiting. That should be done by calling the HistoryManager's
         end_session method."""
         self.stop_now = True
         self.history_manager.save_flag.set()
         self.join()
 
 
 # To match, e.g. ~5/8-~2/3
 range_re = re.compile(r"""
 ((?P<startsess>~?\d+)/)?
 (?P<start>\d+)?
 ((?P<sep>[\-:])
  ((?P<endsess>~?\d+)/)?
  (?P<end>\d+))?
 $""", re.VERBOSE)
 
 
 def extract_hist_ranges(ranges_str):
     """Turn a string of history ranges into 3-tuples of (session, start, stop).
 
     Empty string results in a `[(0, 1, None)]`, i.e. "everything from current
     session".
 
     Examples
     --------
     >>> list(extract_hist_ranges("~8/5-~7/4 2"))
     [(-8, 5, None), (-7, 1, 5), (0, 2, 3)]
     """
     if ranges_str == "":
         yield (0, 1, None)  # Everything from current session
         return
 
     for range_str in ranges_str.split():
         rmatch = range_re.match(range_str)
         if not rmatch:
             continue
         start = rmatch.group("start")
         if start:
             start = int(start)
             end = rmatch.group("end")
             # If no end specified, get (a, a + 1)
             end = int(end) if end else start + 1
         else:  # start not specified
             if not rmatch.group('startsess'):  # no startsess
                 continue
             start = 1
             end = None  # provide the entire session hist
 
         if rmatch.group("sep") == "-":       # 1-3 == 1:4 --> [1, 2, 3]
             end += 1
         startsess = rmatch.group("startsess") or "0"
         endsess = rmatch.group("endsess") or startsess
         startsess = int(startsess.replace("~","-"))
         endsess = int(endsess.replace("~","-"))
         assert endsess >= startsess, "start session must be earlier than end session"
 
         if endsess == startsess:
             yield (startsess, start, end)
             continue
         # Multiple sessions in one range:
         yield (startsess, start, None)
         for sess in range(startsess+1, endsess):
             yield (sess, 1, None)
         yield (endsess, 1, end)
 
 
 def _format_lineno(session, line):
     """Helper function to format line numbers properly."""
     if session == 0:
         return str(line)
     return "%s#%s" % (session, line)

IPython/core/interactiveshell.py

@@ -1,3955 +1,3963 b''
 # -*- coding: utf-8 -*-
 """Main IPython class."""
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2001 Janko Hauser <[e-mail]>
 #  Copyright (C) 2001-2007 Fernando Perez. <[e-mail]>
 #  Copyright (C) 2008-2011  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 
 import abc
 import ast
 import atexit
 import bdb
 import builtins as builtin_mod
 import functools
 import inspect
 import os
 import re
 import runpy
 import shutil
 import subprocess
 import sys
 import tempfile
 import traceback
 import types
 import warnings
 from ast import stmt
 from io import open as io_open
 from logging import error
 from pathlib import Path
 from typing import Callable
 from typing import List as ListType, Dict as DictType, Any as AnyType
 from typing import Optional, Sequence, Tuple
 from warnings import warn
 
 try:
     from pickleshare import PickleShareDB
 except ModuleNotFoundError:
 
     class PickleShareDB:  # type: ignore [no-redef]
         _mock = True
 
         def __init__(self, path):
             pass
 
         def get(self, key, default):
             warn(
                 f"using {key} requires you to install the `pickleshare` library.",
                 stacklevel=2,
             )
             return default
 
         def __setitem__(self, key, value):
             warn(
                 f"using {key} requires you to install the `pickleshare` library.",
                 stacklevel=2,
             )
 
 
 from tempfile import TemporaryDirectory
 from traitlets import (
     Any,
     Bool,
     CaselessStrEnum,
     Dict,
     Enum,
     Instance,
     Integer,
     List,
     Type,
     Unicode,
     default,
     observe,
     validate,
 )
 from traitlets.config.configurable import SingletonConfigurable
 from traitlets.utils.importstring import import_item
 
 import IPython.core.hooks
 from IPython.core import magic, oinspect, page, prefilter, ultratb
 from IPython.core.alias import Alias, AliasManager
 from IPython.core.autocall import ExitAutocall
 from IPython.core.builtin_trap import BuiltinTrap
 from IPython.core.compilerop import CachingCompiler
 from IPython.core.debugger import InterruptiblePdb
 from IPython.core.display_trap import DisplayTrap
 from IPython.core.displayhook import DisplayHook
 from IPython.core.displaypub import DisplayPublisher
 from IPython.core.error import InputRejected, UsageError
 from IPython.core.events import EventManager, available_events
 from IPython.core.extensions import ExtensionManager
 from IPython.core.formatters import DisplayFormatter
 from IPython.core.history import HistoryManager
 from IPython.core.inputtransformer2 import ESC_MAGIC, ESC_MAGIC2
 from IPython.core.logger import Logger
 from IPython.core.macro import Macro
 from IPython.core.payload import PayloadManager
 from IPython.core.prefilter import PrefilterManager
 from IPython.core.profiledir import ProfileDir
 from IPython.core.usage import default_banner
 from IPython.display import display
 from IPython.paths import get_ipython_dir
 from IPython.testing.skipdoctest import skip_doctest
 from IPython.utils import PyColorize, io, openpy, py3compat
 from IPython.utils.decorators import undoc
 from IPython.utils.io import ask_yes_no
 from IPython.utils.ipstruct import Struct
 from IPython.utils.path import ensure_dir_exists, get_home_dir, get_py_filename
 from IPython.utils.process import getoutput, system
 from IPython.utils.strdispatch import StrDispatch
 from IPython.utils.syspathcontext import prepended_to_syspath
 from IPython.utils.text import DollarFormatter, LSString, SList, format_screen
 from IPython.core.oinspect import OInfo
 
 
 sphinxify: Optional[Callable]
 
 try:
     import docrepr.sphinxify as sphx
 
     def sphinxify(oinfo):
         wrapped_docstring = sphx.wrap_main_docstring(oinfo)
 
         def sphinxify_docstring(docstring):
             with TemporaryDirectory() as dirname:
                 return {
                     "text/html": sphx.sphinxify(wrapped_docstring, dirname),
                     "text/plain": docstring,
                 }
 
         return sphinxify_docstring
 except ImportError:
     sphinxify = None
 
 if sys.version_info[:2] < (3, 11):
     from exceptiongroup import BaseExceptionGroup
 
 class ProvisionalWarning(DeprecationWarning):
     """
     Warning class for unstable features
     """
     pass
 
 from ast import Module
 
 _assign_nodes = (ast.AugAssign, ast.AnnAssign, ast.Assign)
 _single_targets_nodes = (ast.AugAssign, ast.AnnAssign)
 
 #-----------------------------------------------------------------------------
 # Await Helpers
 #-----------------------------------------------------------------------------
 
 # we still need to run things using the asyncio eventloop, but there is no
 # async integration
 from .async_helpers import (
     _asyncio_runner,
     _curio_runner,
     _pseudo_sync_runner,
     _should_be_async,
     _trio_runner,
 )
 
 #-----------------------------------------------------------------------------
 # Globals
 #-----------------------------------------------------------------------------
 
 # compiled regexps for autoindent management
 dedent_re = re.compile(r'^\s+raise|^\s+return|^\s+pass')
 
 #-----------------------------------------------------------------------------
 # Utilities
 #-----------------------------------------------------------------------------
 
 
 def is_integer_string(s: str):
     """
     Variant of "str.isnumeric()" that allow negative values and other ints.
     """
     try:
         int(s)
         return True
     except ValueError:
         return False
     raise ValueError("Unexpected error")
 
 
 @undoc
 def softspace(file, newvalue):
     """Copied from code.py, to remove the dependency"""
 
     oldvalue = 0
     try:
         oldvalue = file.softspace
     except AttributeError:
         pass
     try:
         file.softspace = newvalue
     except (AttributeError, TypeError):
         # "attribute-less object" or "read-only attributes"
         pass
     return oldvalue
 
 @undoc
 def no_op(*a, **kw):
     pass
 
 
 class SpaceInInput(Exception): pass
 
 
 class SeparateUnicode(Unicode):
     r"""A Unicode subclass to validate separate_in, separate_out, etc.
 
     This is a Unicode based trait that converts '0'->'' and ``'\\n'->'\n'``.
     """
 
     def validate(self, obj, value):
         if value == '0': value = ''
         value = value.replace('\\n','\n')
         return super(SeparateUnicode, self).validate(obj, value)
 
 
 @undoc
 class DummyMod(object):
     """A dummy module used for IPython's interactive module when
     a namespace must be assigned to the module's __dict__."""
     __spec__ = None
 
 
 class ExecutionInfo(object):
     """The arguments used for a call to :meth:`InteractiveShell.run_cell`
 
     Stores information about what is going to happen.
     """
     raw_cell = None
     store_history = False
     silent = False
     shell_futures = True
     cell_id = None
 
     def __init__(self, raw_cell, store_history, silent, shell_futures, cell_id):
         self.raw_cell = raw_cell
         self.store_history = store_history
         self.silent = silent
         self.shell_futures = shell_futures
         self.cell_id = cell_id
 
     def __repr__(self):
         name = self.__class__.__qualname__
         raw_cell = (
             (self.raw_cell[:50] + "..") if len(self.raw_cell) > 50 else self.raw_cell
         )
         return (
             '<%s object at %x, raw_cell="%s" store_history=%s silent=%s shell_futures=%s cell_id=%s>'
             % (
                 name,
                 id(self),
                 raw_cell,
                 self.store_history,
                 self.silent,
                 self.shell_futures,
                 self.cell_id,
             )
         )
 
 
 class ExecutionResult(object):
     """The result of a call to :meth:`InteractiveShell.run_cell`
 
     Stores information about what took place.
     """
     execution_count = None
     error_before_exec = None
     error_in_exec: Optional[BaseException] = None
     info = None
     result = None
 
     def __init__(self, info):
         self.info = info
 
     @property
     def success(self):
         return (self.error_before_exec is None) and (self.error_in_exec is None)
 
     def raise_error(self):
         """Reraises error if `success` is `False`, otherwise does nothing"""
         if self.error_before_exec is not None:
             raise self.error_before_exec
         if self.error_in_exec is not None:
             raise self.error_in_exec
 
     def __repr__(self):
         name = self.__class__.__qualname__
         return '<%s object at %x, execution_count=%s error_before_exec=%s error_in_exec=%s info=%s result=%s>' %\
                 (name, id(self), self.execution_count, self.error_before_exec, self.error_in_exec, repr(self.info), repr(self.result))
 
 @functools.wraps(io_open)
 def _modified_open(file, *args, **kwargs):
     if file in {0, 1, 2}:
         raise ValueError(
             f"IPython won't let you open fd={file} by default "
             "as it is likely to crash IPython. If you know what you are doing, "
             "you can use builtins' open."
         )
 
     return io_open(file, *args, **kwargs)
 
 class InteractiveShell(SingletonConfigurable):
     """An enhanced, interactive shell for Python."""
 
     _instance = None
 
-    ast_transformers = List([], help=
-        """
+    ast_transformers: List[ast.NodeTransformer] = List(
+        [],
+        help="""
         A list of ast.NodeTransformer subclass instances, which will be applied
         to user input before code is run.
-        """
+        """,
     ).tag(config=True)
 
     autocall = Enum((0,1,2), default_value=0, help=
         """
         Make IPython automatically call any callable object even if you didn't
         type explicit parentheses. For example, 'str 43' becomes 'str(43)'
         automatically. The value can be '0' to disable the feature, '1' for
         'smart' autocall, where it is not applied if there are no more
         arguments on the line, and '2' for 'full' autocall, where all callable
         objects are automatically called (even if no arguments are present).
         """
     ).tag(config=True)
 
     autoindent = Bool(True, help=
         """
         Autoindent IPython code entered interactively.
         """
     ).tag(config=True)
 
     autoawait = Bool(True, help=
         """
         Automatically run await statement in the top level repl.
         """
     ).tag(config=True)
 
     loop_runner_map ={
         'asyncio':(_asyncio_runner, True),
         'curio':(_curio_runner, True),
         'trio':(_trio_runner, True),
         'sync': (_pseudo_sync_runner, False)
     }
 
     loop_runner = Any(default_value="IPython.core.interactiveshell._asyncio_runner",
         allow_none=True,
         help="""Select the loop runner that will be used to execute top-level asynchronous code"""
     ).tag(config=True)
 
     @default('loop_runner')
     def _default_loop_runner(self):
         return import_item("IPython.core.interactiveshell._asyncio_runner")
 
     @validate('loop_runner')
     def _import_runner(self, proposal):
         if isinstance(proposal.value, str):
             if proposal.value in self.loop_runner_map:
                 runner, autoawait = self.loop_runner_map[proposal.value]
                 self.autoawait = autoawait
                 return runner
             runner = import_item(proposal.value)
             if not callable(runner):
                 raise ValueError('loop_runner must be callable')
             return runner
         if not callable(proposal.value):
             raise ValueError('loop_runner must be callable')
         return proposal.value
 
     automagic = Bool(True, help=
         """
         Enable magic commands to be called without the leading %.
         """
     ).tag(config=True)
 
     banner1 = Unicode(default_banner,
         help="""The part of the banner to be printed before the profile"""
     ).tag(config=True)
     banner2 = Unicode('',
         help="""The part of the banner to be printed after the profile"""
     ).tag(config=True)
 
     cache_size = Integer(1000, help=
         """
         Set the size of the output cache.  The default is 1000, you can
         change it permanently in your config file.  Setting it to 0 completely
         disables the caching system, and the minimum value accepted is 3 (if
         you provide a value less than 3, it is reset to 0 and a warning is
         issued).  This limit is defined because otherwise you'll spend more
         time re-flushing a too small cache than working
         """
     ).tag(config=True)
     color_info = Bool(True, help=
         """
         Use colors for displaying information about objects. Because this
         information is passed through a pager (like 'less'), and some pagers
         get confused with color codes, this capability can be turned off.
         """
     ).tag(config=True)
     colors = CaselessStrEnum(('Neutral', 'NoColor','LightBG','Linux'),
                              default_value='Neutral',
         help="Set the color scheme (NoColor, Neutral, Linux, or LightBG)."
     ).tag(config=True)
     debug = Bool(False).tag(config=True)
     disable_failing_post_execute = Bool(False,
         help="Don't call post-execute functions that have failed in the past."
     ).tag(config=True)
     display_formatter = Instance(DisplayFormatter, allow_none=True)
     displayhook_class = Type(DisplayHook)
     display_pub_class = Type(DisplayPublisher)
     compiler_class = Type(CachingCompiler)
     inspector_class = Type(
         oinspect.Inspector, help="Class to use to instantiate the shell inspector"
     ).tag(config=True)
 
     sphinxify_docstring = Bool(False, help=
         """
         Enables rich html representation of docstrings. (This requires the
         docrepr module).
         """).tag(config=True)
 
     @observe("sphinxify_docstring")
     def _sphinxify_docstring_changed(self, change):
         if change['new']:
             warn("`sphinxify_docstring` is provisional since IPython 5.0 and might change in future versions." , ProvisionalWarning)
 
     enable_html_pager = Bool(False, help=
         """
         (Provisional API) enables html representation in mime bundles sent
         to pagers.
         """).tag(config=True)
 
     @observe("enable_html_pager")
     def _enable_html_pager_changed(self, change):
         if change['new']:
             warn("`enable_html_pager` is provisional since IPython 5.0 and might change in future versions.", ProvisionalWarning)
 
     data_pub_class = None
 
     exit_now = Bool(False)
     exiter = Instance(ExitAutocall)
     @default('exiter')
     def _exiter_default(self):
         return ExitAutocall(self)
     # Monotonically increasing execution counter
     execution_count = Integer(1)
     filename = Unicode("<ipython console>")
     ipython_dir= Unicode('').tag(config=True) # Set to get_ipython_dir() in __init__
 
     # Used to transform cells before running them, and check whether code is complete
     input_transformer_manager = Instance('IPython.core.inputtransformer2.TransformerManager',
                                          ())
 
     @property
     def input_transformers_cleanup(self):
         return self.input_transformer_manager.cleanup_transforms
 
     input_transformers_post = List([],
         help="A list of string input transformers, to be applied after IPython's "
              "own input transformations."
     )
 
     @property
     def input_splitter(self):
         """Make this available for backward compatibility (pre-7.0 release) with existing code.
 
         For example, ipykernel ipykernel currently uses
         `shell.input_splitter.check_complete`
         """
         from warnings import warn
         warn("`input_splitter` is deprecated since IPython 7.0, prefer `input_transformer_manager`.",
              DeprecationWarning, stacklevel=2
         )
         return self.input_transformer_manager
 
     logstart = Bool(False, help=
         """
         Start logging to the default log file in overwrite mode.
         Use `logappend` to specify a log file to **append** logs to.
         """
     ).tag(config=True)
     logfile = Unicode('', help=
         """
         The name of the logfile to use.
         """
     ).tag(config=True)
     logappend = Unicode('', help=
         """
         Start logging to the given file in append mode.
         Use `logfile` to specify a log file to **overwrite** logs to.
         """
     ).tag(config=True)
     object_info_string_level = Enum((0,1,2), default_value=0,
     ).tag(config=True)
     pdb = Bool(False, help=
         """
         Automatically call the pdb debugger after every exception.
         """
     ).tag(config=True)
     display_page = Bool(False,
         help="""If True, anything that would be passed to the pager
         will be displayed as regular output instead."""
     ).tag(config=True)
 
 
     show_rewritten_input = Bool(True,
         help="Show rewritten input, e.g. for autocall."
     ).tag(config=True)
 
     quiet = Bool(False).tag(config=True)
 
     history_length = Integer(10000,
         help='Total length of command history'
     ).tag(config=True)
 
     history_load_length = Integer(1000, help=
         """
         The number of saved history entries to be loaded
         into the history buffer at startup.
         """
     ).tag(config=True)
 
     ast_node_interactivity = Enum(['all', 'last', 'last_expr', 'none', 'last_expr_or_assign'],
                                   default_value='last_expr',
                                   help="""
         'all', 'last', 'last_expr' or 'none', 'last_expr_or_assign' specifying
         which nodes should be run interactively (displaying output from expressions).
         """
     ).tag(config=True)
 
     warn_venv = Bool(
         True,
         help="Warn if running in a virtual environment with no IPython installed (so IPython from the global environment is used).",
     ).tag(config=True)
 
     # TODO: this part of prompt management should be moved to the frontends.
     # Use custom TraitTypes that convert '0'->'' and '\\n'->'\n'
     separate_in = SeparateUnicode('\n').tag(config=True)
     separate_out = SeparateUnicode('').tag(config=True)
     separate_out2 = SeparateUnicode('').tag(config=True)
     wildcards_case_sensitive = Bool(True).tag(config=True)
     xmode = CaselessStrEnum(('Context', 'Plain', 'Verbose', 'Minimal'),
                             default_value='Context',
                             help="Switch modes for the IPython exception handlers."
                             ).tag(config=True)
 
     # Subcomponents of InteractiveShell
-    alias_manager = Instance('IPython.core.alias.AliasManager', allow_none=True)
-    prefilter_manager = Instance('IPython.core.prefilter.PrefilterManager', allow_none=True)
-    builtin_trap = Instance('IPython.core.builtin_trap.BuiltinTrap', allow_none=True)
-    display_trap = Instance('IPython.core.display_trap.DisplayTrap', allow_none=True)
-    extension_manager = Instance('IPython.core.extensions.ExtensionManager', allow_none=True)
-    payload_manager = Instance('IPython.core.payload.PayloadManager', allow_none=True)
-    history_manager = Instance('IPython.core.history.HistoryAccessorBase', allow_none=True)
-    magics_manager = Instance('IPython.core.magic.MagicsManager', allow_none=True)
+    alias_manager = Instance("IPython.core.alias.AliasManager", allow_none=True)
+    prefilter_manager = Instance(
+        "IPython.core.prefilter.PrefilterManager", allow_none=True
+    )
+    builtin_trap = Instance("IPython.core.builtin_trap.BuiltinTrap")
+    display_trap = Instance("IPython.core.display_trap.DisplayTrap")
+    extension_manager = Instance(
+        "IPython.core.extensions.ExtensionManager", allow_none=True
+    )
+    payload_manager = Instance("IPython.core.payload.PayloadManager", allow_none=True)
+    history_manager = Instance(
+        "IPython.core.history.HistoryAccessorBase", allow_none=True
+    )
+    magics_manager = Instance("IPython.core.magic.MagicsManager")
 
     profile_dir = Instance('IPython.core.application.ProfileDir', allow_none=True)
     @property
     def profile(self):
         if self.profile_dir is not None:
             name = os.path.basename(self.profile_dir.location)
             return name.replace('profile_','')
 
 
     # Private interface
     _post_execute = Dict()
 
     # Tracks any GUI loop loaded for pylab
     pylab_gui_select = None
 
     last_execution_succeeded = Bool(True, help='Did last executed command succeeded')
 
     last_execution_result = Instance('IPython.core.interactiveshell.ExecutionResult', help='Result of executing the last command', allow_none=True)
 
     def __init__(self, ipython_dir=None, profile_dir=None,
                  user_module=None, user_ns=None,
                  custom_exceptions=((), None), **kwargs):
         # This is where traits with a config_key argument are updated
         # from the values on config.
         super(InteractiveShell, self).__init__(**kwargs)
         if 'PromptManager' in self.config:
             warn('As of IPython 5.0 `PromptManager` config will have no effect'
                  ' and has been replaced by TerminalInteractiveShell.prompts_class')
         self.configurables = [self]
 
         # These are relatively independent and stateless
         self.init_ipython_dir(ipython_dir)
         self.init_profile_dir(profile_dir)
         self.init_instance_attrs()
         self.init_environment()
 
         # Check if we're in a virtualenv, and set up sys.path.
         self.init_virtualenv()
 
         # Create namespaces (user_ns, user_global_ns, etc.)
         self.init_create_namespaces(user_module, user_ns)
         # This has to be done after init_create_namespaces because it uses
         # something in self.user_ns, but before init_sys_modules, which
         # is the first thing to modify sys.
         # TODO: When we override sys.stdout and sys.stderr before this class
         # is created, we are saving the overridden ones here. Not sure if this
         # is what we want to do.
         self.save_sys_module_state()
         self.init_sys_modules()
 
         # While we're trying to have each part of the code directly access what
         # it needs without keeping redundant references to objects, we have too
         # much legacy code that expects ip.db to exist.
         self.db = PickleShareDB(os.path.join(self.profile_dir.location, 'db'))
 
         self.init_history()
         self.init_encoding()
         self.init_prefilter()
 
         self.init_syntax_highlighting()
         self.init_hooks()
         self.init_events()
         self.init_pushd_popd_magic()
         self.init_user_ns()
         self.init_logger()
         self.init_builtins()
 
         # The following was in post_config_initialization
         self.init_inspector()
         self.raw_input_original = input
         self.init_completer()
         # TODO: init_io() needs to happen before init_traceback handlers
         # because the traceback handlers hardcode the stdout/stderr streams.
         # This logic in in debugger.Pdb and should eventually be changed.
         self.init_io()
         self.init_traceback_handlers(custom_exceptions)
         self.init_prompts()
         self.init_display_formatter()
         self.init_display_pub()
         self.init_data_pub()
         self.init_displayhook()
         self.init_magics()
         self.init_alias()
         self.init_logstart()
         self.init_pdb()
         self.init_extension_manager()
         self.init_payload()
         self.events.trigger('shell_initialized', self)
         atexit.register(self.atexit_operations)
 
         # The trio runner is used for running Trio in the foreground thread. It
         # is different from `_trio_runner(async_fn)` in `async_helpers.py`
         # which calls `trio.run()` for every cell. This runner runs all cells
         # inside a single Trio event loop. If used, it is set from
         # `ipykernel.kernelapp`.
         self.trio_runner = None
 
     def get_ipython(self):
         """Return the currently running IPython instance."""
         return self
 
     #-------------------------------------------------------------------------
     # Trait changed handlers
     #-------------------------------------------------------------------------
     @observe('ipython_dir')
     def _ipython_dir_changed(self, change):
         ensure_dir_exists(change['new'])
 
     def set_autoindent(self,value=None):
         """Set the autoindent flag.
 
         If called with no arguments, it acts as a toggle."""
         if value is None:
             self.autoindent = not self.autoindent
         else:
             self.autoindent = value
 
     def set_trio_runner(self, tr):
         self.trio_runner = tr
 
     #-------------------------------------------------------------------------
     # init_* methods called by __init__
     #-------------------------------------------------------------------------
 
     def init_ipython_dir(self, ipython_dir):
         if ipython_dir is not None:
             self.ipython_dir = ipython_dir
             return
 
         self.ipython_dir = get_ipython_dir()
 
     def init_profile_dir(self, profile_dir):
         if profile_dir is not None:
             self.profile_dir = profile_dir
             return
         self.profile_dir = ProfileDir.create_profile_dir_by_name(
             self.ipython_dir, "default"
         )
 
     def init_instance_attrs(self):
         self.more = False
 
         # command compiler
         self.compile = self.compiler_class()
 
         # Make an empty namespace, which extension writers can rely on both
         # existing and NEVER being used by ipython itself.  This gives them a
         # convenient location for storing additional information and state
         # their extensions may require, without fear of collisions with other
         # ipython names that may develop later.
         self.meta = Struct()
 
         # Temporary files used for various purposes.  Deleted at exit.
         # The files here are stored with Path from Pathlib
         self.tempfiles = []
         self.tempdirs = []
 
         # keep track of where we started running (mainly for crash post-mortem)
         # This is not being used anywhere currently.
         self.starting_dir = os.getcwd()
 
         # Indentation management
         self.indent_current_nsp = 0
 
         # Dict to track post-execution functions that have been registered
         self._post_execute = {}
 
     def init_environment(self):
         """Any changes we need to make to the user's environment."""
         pass
 
     def init_encoding(self):
         # Get system encoding at startup time.  Certain terminals (like Emacs
         # under Win32 have it set to None, and we need to have a known valid
         # encoding to use in the raw_input() method
         try:
             self.stdin_encoding = sys.stdin.encoding or 'ascii'
         except AttributeError:
             self.stdin_encoding = 'ascii'
 
 
     @observe('colors')
     def init_syntax_highlighting(self, changes=None):
         # Python source parser/formatter for syntax highlighting
         pyformat = PyColorize.Parser(style=self.colors, parent=self).format
         self.pycolorize = lambda src: pyformat(src,'str')
 
     def refresh_style(self):
         # No-op here, used in subclass
         pass
 
     def init_pushd_popd_magic(self):
         # for pushd/popd management
         self.home_dir = get_home_dir()
 
         self.dir_stack = []
 
     def init_logger(self):
         self.logger = Logger(self.home_dir, logfname='ipython_log.py',
                              logmode='rotate')
 
     def init_logstart(self):
         """Initialize logging in case it was requested at the command line.
         """
         if self.logappend:
             self.magic('logstart %s append' % self.logappend)
         elif self.logfile:
             self.magic('logstart %s' % self.logfile)
         elif self.logstart:
             self.magic('logstart')
 
 
     def init_builtins(self):
         # A single, static flag that we set to True.  Its presence indicates
         # that an IPython shell has been created, and we make no attempts at
         # removing on exit or representing the existence of more than one
         # IPython at a time.
         builtin_mod.__dict__['__IPYTHON__'] = True
         builtin_mod.__dict__['display'] = display
 
         self.builtin_trap = BuiltinTrap(shell=self)
 
     @observe('colors')
     def init_inspector(self, changes=None):
         # Object inspector
         self.inspector = self.inspector_class(
             oinspect.InspectColors,
             PyColorize.ANSICodeColors,
             self.colors,
             self.object_info_string_level,
         )
 
     def init_io(self):
         # implemented in subclasses, TerminalInteractiveShell does call
         # colorama.init().
         pass
 
     def init_prompts(self):
         # Set system prompts, so that scripts can decide if they are running
         # interactively.
         sys.ps1 = 'In : '
         sys.ps2 = '...: '
         sys.ps3 = 'Out: '
 
     def init_display_formatter(self):
         self.display_formatter = DisplayFormatter(parent=self)
         self.configurables.append(self.display_formatter)
 
     def init_display_pub(self):
         self.display_pub = self.display_pub_class(parent=self, shell=self)
         self.configurables.append(self.display_pub)
 
     def init_data_pub(self):
         if not self.data_pub_class:
             self.data_pub = None
             return
         self.data_pub = self.data_pub_class(parent=self)
         self.configurables.append(self.data_pub)
 
     def init_displayhook(self):
         # Initialize displayhook, set in/out prompts and printing system
         self.displayhook = self.displayhook_class(
             parent=self,
             shell=self,
             cache_size=self.cache_size,
         )
         self.configurables.append(self.displayhook)
         # This is a context manager that installs/revmoes the displayhook at
         # the appropriate time.
         self.display_trap = DisplayTrap(hook=self.displayhook)
 
     @staticmethod
     def get_path_links(p: Path):
         """Gets path links including all symlinks
 
         Examples
         --------
         In [1]: from IPython.core.interactiveshell import InteractiveShell
 
         In [2]: import sys, pathlib
 
         In [3]: paths = InteractiveShell.get_path_links(pathlib.Path(sys.executable))
 
         In [4]: len(paths) == len(set(paths))
         Out[4]: True
 
         In [5]: bool(paths)
         Out[5]: True
         """
         paths = [p]
         while p.is_symlink():
             new_path = Path(os.readlink(p))
             if not new_path.is_absolute():
                 new_path = p.parent / new_path
             p = new_path
             paths.append(p)
         return paths
 
     def init_virtualenv(self):
         """Add the current virtualenv to sys.path so the user can import modules from it.
         This isn't perfect: it doesn't use the Python interpreter with which the
         virtualenv was built, and it ignores the --no-site-packages option. A
         warning will appear suggesting the user installs IPython in the
         virtualenv, but for many cases, it probably works well enough.
 
         Adapted from code snippets online.
 
         http://blog.ufsoft.org/2009/1/29/ipython-and-virtualenv
         """
         if 'VIRTUAL_ENV' not in os.environ:
             # Not in a virtualenv
             return
         elif os.environ["VIRTUAL_ENV"] == "":
             warn("Virtual env path set to '', please check if this is intended.")
             return
 
         p = Path(sys.executable)
         p_venv = Path(os.environ["VIRTUAL_ENV"])
 
         # fallback venv detection:
         # stdlib venv may symlink sys.executable, so we can't use realpath.
         # but others can symlink *to* the venv Python, so we can't just use sys.executable.
         # So we just check every item in the symlink tree (generally <= 3)
         paths = self.get_path_links(p)
 
         # In Cygwin paths like "c:\..." and '\cygdrive\c\...' are possible
         if p_venv.parts[1] == "cygdrive":
             drive_name = p_venv.parts[2]
             p_venv = (drive_name + ":/") / Path(*p_venv.parts[3:])
 
         if any(p_venv == p.parents[1] for p in paths):
             # Our exe is inside or has access to the virtualenv, don't need to do anything.
             return
 
         if sys.platform == "win32":
             virtual_env = str(Path(os.environ["VIRTUAL_ENV"], "Lib", "site-packages"))
         else:
             virtual_env_path = Path(
                 os.environ["VIRTUAL_ENV"], "lib", "python{}.{}", "site-packages"
             )
             p_ver = sys.version_info[:2]
 
             # Predict version from py[thon]-x.x in the $VIRTUAL_ENV
             re_m = re.search(r"\bpy(?:thon)?([23])\.(\d+)\b", os.environ["VIRTUAL_ENV"])
             if re_m:
                 predicted_path = Path(str(virtual_env_path).format(*re_m.groups()))
                 if predicted_path.exists():
                     p_ver = re_m.groups()
 
             virtual_env = str(virtual_env_path).format(*p_ver)
         if self.warn_venv:
             warn(
                 "Attempting to work in a virtualenv. If you encounter problems, "
                 "please install IPython inside the virtualenv."
             )
         import site
         sys.path.insert(0, virtual_env)
         site.addsitedir(virtual_env)
 
     #-------------------------------------------------------------------------
     # Things related to injections into the sys module
     #-------------------------------------------------------------------------
 
     def save_sys_module_state(self):
         """Save the state of hooks in the sys module.
 
         This has to be called after self.user_module is created.
         """
         self._orig_sys_module_state = {'stdin': sys.stdin,
                                        'stdout': sys.stdout,
                                        'stderr': sys.stderr,
                                        'excepthook': sys.excepthook}
         self._orig_sys_modules_main_name = self.user_module.__name__
         self._orig_sys_modules_main_mod = sys.modules.get(self.user_module.__name__)
 
     def restore_sys_module_state(self):
         """Restore the state of the sys module."""
         try:
             for k, v in self._orig_sys_module_state.items():
                 setattr(sys, k, v)
         except AttributeError:
             pass
         # Reset what what done in self.init_sys_modules
         if self._orig_sys_modules_main_mod is not None:
             sys.modules[self._orig_sys_modules_main_name] = self._orig_sys_modules_main_mod
 
     #-------------------------------------------------------------------------
     # Things related to the banner
     #-------------------------------------------------------------------------
 
     @property
     def banner(self):
         banner = self.banner1
         if self.profile and self.profile != 'default':
             banner += '\nIPython profile: %s\n' % self.profile
         if self.banner2:
             banner += '\n' + self.banner2
         return banner
 
     def show_banner(self, banner=None):
         if banner is None:
             banner = self.banner
         sys.stdout.write(banner)
 
     #-------------------------------------------------------------------------
     # Things related to hooks
     #-------------------------------------------------------------------------
 
     def init_hooks(self):
         # hooks holds pointers used for user-side customizations
         self.hooks = Struct()
 
         self.strdispatchers = {}
 
         # Set all default hooks, defined in the IPython.hooks module.
         hooks = IPython.core.hooks
         for hook_name in hooks.__all__:
             # default hooks have priority 100, i.e. low; user hooks should have
             # 0-100 priority
             self.set_hook(hook_name, getattr(hooks, hook_name), 100)
 
         if self.display_page:
             self.set_hook('show_in_pager', page.as_hook(page.display_page), 90)
 
     def set_hook(self, name, hook, priority=50, str_key=None, re_key=None):
         """set_hook(name,hook) -> sets an internal IPython hook.
 
         IPython exposes some of its internal API as user-modifiable hooks.  By
         adding your function to one of these hooks, you can modify IPython's
         behavior to call at runtime your own routines."""
 
         # At some point in the future, this should validate the hook before it
         # accepts it.  Probably at least check that the hook takes the number
         # of args it's supposed to.
 
         f = types.MethodType(hook,self)
 
         # check if the hook is for strdispatcher first
         if str_key is not None:
             sdp = self.strdispatchers.get(name, StrDispatch())
             sdp.add_s(str_key, f, priority )
             self.strdispatchers[name] = sdp
             return
         if re_key is not None:
             sdp = self.strdispatchers.get(name, StrDispatch())
             sdp.add_re(re.compile(re_key), f, priority )
             self.strdispatchers[name] = sdp
             return
 
         dp = getattr(self.hooks, name, None)
         if name not in IPython.core.hooks.__all__:
             print("Warning! Hook '%s' is not one of %s" % \
                   (name, IPython.core.hooks.__all__ ))
 
         if name in IPython.core.hooks.deprecated:
             alternative = IPython.core.hooks.deprecated[name]
             raise ValueError(
                 "Hook {} has been deprecated since IPython 5.0. Use {} instead.".format(
                     name, alternative
                 )
             )
 
         if not dp:
             dp = IPython.core.hooks.CommandChainDispatcher()
 
         try:
             dp.add(f,priority)
         except AttributeError:
             # it was not commandchain, plain old func - replace
             dp = f
 
         setattr(self.hooks,name, dp)
 
     #-------------------------------------------------------------------------
     # Things related to events
     #-------------------------------------------------------------------------
 
     def init_events(self):
         self.events = EventManager(self, available_events)
 
         self.events.register("pre_execute", self._clear_warning_registry)
 
     def register_post_execute(self, func):
         """DEPRECATED: Use ip.events.register('post_run_cell', func)
 
         Register a function for calling after code execution.
         """
         raise ValueError(
             "ip.register_post_execute is deprecated since IPython 1.0, use "
             "ip.events.register('post_run_cell', func) instead."
         )
 
     def _clear_warning_registry(self):
         # clear the warning registry, so that different code blocks with
         # overlapping line number ranges don't cause spurious suppression of
         # warnings (see gh-6611 for details)
         if "__warningregistry__" in self.user_global_ns:
             del self.user_global_ns["__warningregistry__"]
 
     #-------------------------------------------------------------------------
     # Things related to the "main" module
     #-------------------------------------------------------------------------
 
     def new_main_mod(self, filename, modname):
         """Return a new 'main' module object for user code execution.
 
         ``filename`` should be the path of the script which will be run in the
         module. Requests with the same filename will get the same module, with
         its namespace cleared.
 
         ``modname`` should be the module name - normally either '__main__' or
         the basename of the file without the extension.
 
         When scripts are executed via %run, we must keep a reference to their
         __main__ module around so that Python doesn't
         clear it, rendering references to module globals useless.
 
         This method keeps said reference in a private dict, keyed by the
         absolute path of the script. This way, for multiple executions of the
         same script we only keep one copy of the namespace (the last one),
         thus preventing memory leaks from old references while allowing the
         objects from the last execution to be accessible.
         """
         filename = os.path.abspath(filename)
         try:
             main_mod = self._main_mod_cache[filename]
         except KeyError:
             main_mod = self._main_mod_cache[filename] = types.ModuleType(
                         modname,
                         doc="Module created for script run in IPython")
         else:
             main_mod.__dict__.clear()
             main_mod.__name__ = modname
 
         main_mod.__file__ = filename
         # It seems pydoc (and perhaps others) needs any module instance to
         # implement a __nonzero__ method
         main_mod.__nonzero__ = lambda : True
 
         return main_mod
 
     def clear_main_mod_cache(self):
         """Clear the cache of main modules.
 
         Mainly for use by utilities like %reset.
 
         Examples
         --------
         In [15]: import IPython
 
         In [16]: m = _ip.new_main_mod(IPython.__file__, 'IPython')
 
         In [17]: len(_ip._main_mod_cache) > 0
         Out[17]: True
 
         In [18]: _ip.clear_main_mod_cache()
 
         In [19]: len(_ip._main_mod_cache) == 0
         Out[19]: True
         """
         self._main_mod_cache.clear()
 
     #-------------------------------------------------------------------------
     # Things related to debugging
     #-------------------------------------------------------------------------
 
     def init_pdb(self):
         # Set calling of pdb on exceptions
         # self.call_pdb is a property
         self.call_pdb = self.pdb
 
     def _get_call_pdb(self):
         return self._call_pdb
 
     def _set_call_pdb(self,val):
 
         if val not in (0,1,False,True):
             raise ValueError('new call_pdb value must be boolean')
 
         # store value in instance
         self._call_pdb = val
 
         # notify the actual exception handlers
         self.InteractiveTB.call_pdb = val
 
     call_pdb = property(_get_call_pdb,_set_call_pdb,None,
                         'Control auto-activation of pdb at exceptions')
 
     def debugger(self,force=False):
         """Call the pdb debugger.
 
         Keywords:
 
           - force(False): by default, this routine checks the instance call_pdb
             flag and does not actually invoke the debugger if the flag is false.
             The 'force' option forces the debugger to activate even if the flag
             is false.
         """
 
         if not (force or self.call_pdb):
             return
 
         if not hasattr(sys,'last_traceback'):
             error('No traceback has been produced, nothing to debug.')
             return
 
         self.InteractiveTB.debugger(force=True)
 
     #-------------------------------------------------------------------------
     # Things related to IPython's various namespaces
     #-------------------------------------------------------------------------
     default_user_namespaces = True
 
     def init_create_namespaces(self, user_module=None, user_ns=None):
         # Create the namespace where the user will operate.  user_ns is
         # normally the only one used, and it is passed to the exec calls as
         # the locals argument.  But we do carry a user_global_ns namespace
         # given as the exec 'globals' argument,  This is useful in embedding
         # situations where the ipython shell opens in a context where the
         # distinction between locals and globals is meaningful.  For
         # non-embedded contexts, it is just the same object as the user_ns dict.
 
         # FIXME. For some strange reason, __builtins__ is showing up at user
         # level as a dict instead of a module. This is a manual fix, but I
         # should really track down where the problem is coming from. Alex
         # Schmolck reported this problem first.
 
         # A useful post by Alex Martelli on this topic:
         # Re: inconsistent value from __builtins__
         # Von: Alex Martelli <[e-mail]>
         # Datum: Freitag 01 Oktober 2004 04:45:34 nachmittags/abends
         # Gruppen: comp.lang.python
 
         # Michael Hohn <[e-mail]> wrote:
         # > >>> print type(builtin_check.get_global_binding('__builtins__'))
         # > <type 'dict'>
         # > >>> print type(__builtins__)
         # > <type 'module'>
         # > Is this difference in return value intentional?
 
         # Well, it's documented that '__builtins__' can be either a dictionary
         # or a module, and it's been that way for a long time. Whether it's
         # intentional (or sensible), I don't know. In any case, the idea is
         # that if you need to access the built-in namespace directly, you
         # should start with "import __builtin__" (note, no 's') which will
         # definitely give you a module. Yeah, it's somewhat confusing:-(.
 
         # These routines return a properly built module and dict as needed by
         # the rest of the code, and can also be used by extension writers to
         # generate properly initialized namespaces.
         if (user_ns is not None) or (user_module is not None):
             self.default_user_namespaces = False
         self.user_module, self.user_ns = self.prepare_user_module(user_module, user_ns)
 
         # A record of hidden variables we have added to the user namespace, so
         # we can list later only variables defined in actual interactive use.
         self.user_ns_hidden = {}
 
         # Now that FakeModule produces a real module, we've run into a nasty
         # problem: after script execution (via %run), the module where the user
         # code ran is deleted.  Now that this object is a true module (needed
         # so doctest and other tools work correctly), the Python module
         # teardown mechanism runs over it, and sets to None every variable
         # present in that module.  Top-level references to objects from the
         # script survive, because the user_ns is updated with them.  However,
         # calling functions defined in the script that use other things from
         # the script will fail, because the function's closure had references
         # to the original objects, which are now all None.  So we must protect
         # these modules from deletion by keeping a cache.
         #
         # To avoid keeping stale modules around (we only need the one from the
         # last run), we use a dict keyed with the full path to the script, so
         # only the last version of the module is held in the cache.  Note,
         # however, that we must cache the module *namespace contents* (their
         # __dict__).  Because if we try to cache the actual modules, old ones
         # (uncached) could be destroyed while still holding references (such as
         # those held by GUI objects that tend to be long-lived)>
         #
         # The %reset command will flush this cache.  See the cache_main_mod()
         # and clear_main_mod_cache() methods for details on use.
 
         # This is the cache used for 'main' namespaces
         self._main_mod_cache = {}
 
         # A table holding all the namespaces IPython deals with, so that
         # introspection facilities can search easily.
         self.ns_table = {'user_global':self.user_module.__dict__,
                          'user_local':self.user_ns,
                          'builtin':builtin_mod.__dict__
                          }
 
     @property
     def user_global_ns(self):
         return self.user_module.__dict__
 
     def prepare_user_module(self, user_module=None, user_ns=None):
         """Prepare the module and namespace in which user code will be run.
 
         When IPython is started normally, both parameters are None: a new module
         is created automatically, and its __dict__ used as the namespace.
 
         If only user_module is provided, its __dict__ is used as the namespace.
         If only user_ns is provided, a dummy module is created, and user_ns
         becomes the global namespace. If both are provided (as they may be
         when embedding), user_ns is the local namespace, and user_module
         provides the global namespace.
 
         Parameters
         ----------
         user_module : module, optional
             The current user module in which IPython is being run. If None,
             a clean module will be created.
         user_ns : dict, optional
             A namespace in which to run interactive commands.
 
         Returns
         -------
         A tuple of user_module and user_ns, each properly initialised.
         """
         if user_module is None and user_ns is not None:
             user_ns.setdefault("__name__", "__main__")
             user_module = DummyMod()
             user_module.__dict__ = user_ns
 
         if user_module is None:
             user_module = types.ModuleType("__main__",
                 doc="Automatically created module for IPython interactive environment")
 
         # We must ensure that __builtin__ (without the final 's') is always
         # available and pointing to the __builtin__ *module*.  For more details:
         # http://mail.python.org/pipermail/python-dev/2001-April/014068.html
         user_module.__dict__.setdefault('__builtin__', builtin_mod)
         user_module.__dict__.setdefault('__builtins__', builtin_mod)
 
         if user_ns is None:
             user_ns = user_module.__dict__
 
         return user_module, user_ns
 
     def init_sys_modules(self):
         # We need to insert into sys.modules something that looks like a
         # module but which accesses the IPython namespace, for shelve and
         # pickle to work interactively. Normally they rely on getting
         # everything out of __main__, but for embedding purposes each IPython
         # instance has its own private namespace, so we can't go shoving
         # everything into __main__.
 
         # note, however, that we should only do this for non-embedded
         # ipythons, which really mimic the __main__.__dict__ with their own
         # namespace.  Embedded instances, on the other hand, should not do
         # this because they need to manage the user local/global namespaces
         # only, but they live within a 'normal' __main__ (meaning, they
         # shouldn't overtake the execution environment of the script they're
         # embedded in).
 
         # This is overridden in the InteractiveShellEmbed subclass to a no-op.
         main_name = self.user_module.__name__
         sys.modules[main_name] = self.user_module
 
     def init_user_ns(self):
         """Initialize all user-visible namespaces to their minimum defaults.
 
         Certain history lists are also initialized here, as they effectively
         act as user namespaces.
 
         Notes
         -----
         All data structures here are only filled in, they are NOT reset by this
         method.  If they were not empty before, data will simply be added to
         them.
         """
         # This function works in two parts: first we put a few things in
         # user_ns, and we sync that contents into user_ns_hidden so that these
         # initial variables aren't shown by %who.  After the sync, we add the
         # rest of what we *do* want the user to see with %who even on a new
         # session (probably nothing, so they really only see their own stuff)
 
         # The user dict must *always* have a __builtin__ reference to the
         # Python standard __builtin__ namespace,  which must be imported.
         # This is so that certain operations in prompt evaluation can be
         # reliably executed with builtins.  Note that we can NOT use
         # __builtins__ (note the 's'),  because that can either be a dict or a
         # module, and can even mutate at runtime, depending on the context
         # (Python makes no guarantees on it).  In contrast, __builtin__ is
         # always a module object, though it must be explicitly imported.
 
         # For more details:
         # http://mail.python.org/pipermail/python-dev/2001-April/014068.html
         ns = {}
 
         # make global variables for user access to the histories
         ns['_ih'] = self.history_manager.input_hist_parsed
         ns['_oh'] = self.history_manager.output_hist
         ns['_dh'] = self.history_manager.dir_hist
 
         # user aliases to input and output histories.  These shouldn't show up
         # in %who, as they can have very large reprs.
         ns['In']  = self.history_manager.input_hist_parsed
         ns['Out'] = self.history_manager.output_hist
 
         # Store myself as the public api!!!
         ns['get_ipython'] = self.get_ipython
 
         ns['exit'] = self.exiter
         ns['quit'] = self.exiter
         ns["open"] = _modified_open
 
         # Sync what we've added so far to user_ns_hidden so these aren't seen
         # by %who
         self.user_ns_hidden.update(ns)
 
         # Anything put into ns now would show up in %who.  Think twice before
         # putting anything here, as we really want %who to show the user their
         # stuff, not our variables.
 
         # Finally, update the real user's namespace
         self.user_ns.update(ns)
 
     @property
     def all_ns_refs(self):
         """Get a list of references to all the namespace dictionaries in which
         IPython might store a user-created object.
 
         Note that this does not include the displayhook, which also caches
         objects from the output."""
         return [self.user_ns, self.user_global_ns, self.user_ns_hidden] + \
                [m.__dict__ for m in self._main_mod_cache.values()]
 
     def reset(self, new_session=True, aggressive=False):
         """Clear all internal namespaces, and attempt to release references to
         user objects.
 
         If new_session is True, a new history session will be opened.
         """
         # Clear histories
+        assert self.history_manager is not None
         self.history_manager.reset(new_session)
         # Reset counter used to index all histories
         if new_session:
             self.execution_count = 1
 
         # Reset last execution result
         self.last_execution_succeeded = True
         self.last_execution_result = None
 
         # Flush cached output items
         if self.displayhook.do_full_cache:
             self.displayhook.flush()
 
         # The main execution namespaces must be cleared very carefully,
         # skipping the deletion of the builtin-related keys, because doing so
         # would cause errors in many object's __del__ methods.
         if self.user_ns is not self.user_global_ns:
             self.user_ns.clear()
         ns = self.user_global_ns
         drop_keys = set(ns.keys())
         drop_keys.discard('__builtin__')
         drop_keys.discard('__builtins__')
         drop_keys.discard('__name__')
         for k in drop_keys:
             del ns[k]
 
         self.user_ns_hidden.clear()
 
         # Restore the user namespaces to minimal usability
         self.init_user_ns()
         if aggressive and not hasattr(self, "_sys_modules_keys"):
             print("Cannot restore sys.module, no snapshot")
         elif aggressive:
             print("culling sys module...")
             current_keys = set(sys.modules.keys())
             for k in current_keys - self._sys_modules_keys:
                 if k.startswith("multiprocessing"):
                     continue
                 del sys.modules[k]
 
         # Restore the default and user aliases
         self.alias_manager.clear_aliases()
         self.alias_manager.init_aliases()
 
         # Now define aliases that only make sense on the terminal, because they
         # need direct access to the console in a way that we can't emulate in
         # GUI or web frontend
         if os.name == 'posix':
             for cmd in ('clear', 'more', 'less', 'man'):
                 if cmd not in self.magics_manager.magics['line']:
                     self.alias_manager.soft_define_alias(cmd, cmd)
 
         # Flush the private list of module references kept for script
         # execution protection
         self.clear_main_mod_cache()
 
     def del_var(self, varname, by_name=False):
         """Delete a variable from the various namespaces, so that, as
         far as possible, we're not keeping any hidden references to it.
 
         Parameters
         ----------
         varname : str
             The name of the variable to delete.
         by_name : bool
             If True, delete variables with the given name in each
             namespace. If False (default), find the variable in the user
             namespace, and delete references to it.
         """
         if varname in ('__builtin__', '__builtins__'):
             raise ValueError("Refusing to delete %s" % varname)
 
         ns_refs = self.all_ns_refs
 
         if by_name:                    # Delete by name
             for ns in ns_refs:
                 try:
                     del ns[varname]
                 except KeyError:
                     pass
         else:                         # Delete by object
             try:
                 obj = self.user_ns[varname]
             except KeyError as e:
                 raise NameError("name '%s' is not defined" % varname) from e
             # Also check in output history
+            assert self.history_manager is not None
             ns_refs.append(self.history_manager.output_hist)
             for ns in ns_refs:
                 to_delete = [n for n, o in ns.items() if o is obj]
                 for name in to_delete:
                     del ns[name]
 
             # Ensure it is removed from the last execution result
             if self.last_execution_result.result is obj:
                 self.last_execution_result = None
 
             # displayhook keeps extra references, but not in a dictionary
             for name in ('_', '__', '___'):
                 if getattr(self.displayhook, name) is obj:
                     setattr(self.displayhook, name, None)
 
     def reset_selective(self, regex=None):
         """Clear selective variables from internal namespaces based on a
         specified regular expression.
 
         Parameters
         ----------
         regex : string or compiled pattern, optional
             A regular expression pattern that will be used in searching
             variable names in the users namespaces.
         """
         if regex is not None:
             try:
                 m = re.compile(regex)
             except TypeError as e:
                 raise TypeError('regex must be a string or compiled pattern') from e
             # Search for keys in each namespace that match the given regex
             # If a match is found, delete the key/value pair.
             for ns in self.all_ns_refs:
                 for var in ns:
                     if m.search(var):
                         del ns[var]
 
     def push(self, variables, interactive=True):
         """Inject a group of variables into the IPython user namespace.
 
         Parameters
         ----------
         variables : dict, str or list/tuple of str
             The variables to inject into the user's namespace.  If a dict, a
             simple update is done.  If a str, the string is assumed to have
             variable names separated by spaces.  A list/tuple of str can also
             be used to give the variable names.  If just the variable names are
             give (list/tuple/str) then the variable values looked up in the
             callers frame.
         interactive : bool
             If True (default), the variables will be listed with the ``who``
             magic.
         """
         vdict = None
 
         # We need a dict of name/value pairs to do namespace updates.
         if isinstance(variables, dict):
             vdict = variables
         elif isinstance(variables, (str, list, tuple)):
             if isinstance(variables, str):
                 vlist = variables.split()
             else:
                 vlist = variables
             vdict = {}
             cf = sys._getframe(1)
             for name in vlist:
                 try:
                     vdict[name] = eval(name, cf.f_globals, cf.f_locals)
                 except:
                     print('Could not get variable %s from %s' %
                            (name,cf.f_code.co_name))
         else:
             raise ValueError('variables must be a dict/str/list/tuple')
 
         # Propagate variables to user namespace
         self.user_ns.update(vdict)
 
         # And configure interactive visibility
         user_ns_hidden = self.user_ns_hidden
         if interactive:
             for name in vdict:
                 user_ns_hidden.pop(name, None)
         else:
             user_ns_hidden.update(vdict)
 
     def drop_by_id(self, variables):
         """Remove a dict of variables from the user namespace, if they are the
         same as the values in the dictionary.
 
         This is intended for use by extensions: variables that they've added can
         be taken back out if they are unloaded, without removing any that the
         user has overwritten.
 
         Parameters
         ----------
         variables : dict
             A dictionary mapping object names (as strings) to the objects.
         """
         for name, obj in variables.items():
             if name in self.user_ns and self.user_ns[name] is obj:
                 del self.user_ns[name]
                 self.user_ns_hidden.pop(name, None)
 
     #-------------------------------------------------------------------------
     # Things related to object introspection
     #-------------------------------------------------------------------------
     @staticmethod
     def _find_parts(oname: str) -> Tuple[bool, ListType[str]]:
         """
         Given an object name, return a list of parts of this object name.
 
         Basically split on docs when using attribute access,
         and extract the value when using square bracket.
 
 
         For example foo.bar[3].baz[x] -> foo, bar, 3, baz, x
 
 
         Returns
         -------
         parts_ok: bool
             wether we were properly able to parse parts.
         parts: list of str
             extracted parts
 
 
 
         """
         raw_parts = oname.split(".")
         parts = []
         parts_ok = True
         for p in raw_parts:
             if p.endswith("]"):
                 var, *indices = p.split("[")
                 if not var.isidentifier():
                     parts_ok = False
                     break
                 parts.append(var)
                 for ind in indices:
                     if ind[-1] != "]" and not is_integer_string(ind[:-1]):
                         parts_ok = False
                         break
                     parts.append(ind[:-1])
                 continue
 
             if not p.isidentifier():
                 parts_ok = False
             parts.append(p)
 
         return parts_ok, parts
 
     def _ofind(
         self, oname: str, namespaces: Optional[Sequence[Tuple[str, AnyType]]] = None
     ) -> OInfo:
         """Find an object in the available namespaces.
 
 
         Returns
         -------
         OInfo with fields:
           - ismagic
           - isalias
           - found
           - obj
           - namespac
           - parent
 
         Has special code to detect magic functions.
         """
         oname = oname.strip()
         parts_ok, parts = self._find_parts(oname)
 
         if (
             not oname.startswith(ESC_MAGIC)
             and not oname.startswith(ESC_MAGIC2)
             and not parts_ok
         ):
             return OInfo(
                 ismagic=False,
                 isalias=False,
                 found=False,
                 obj=None,
                 namespace=None,
                 parent=None,
             )
 
         if namespaces is None:
             # Namespaces to search in:
             # Put them in a list. The order is important so that we
             # find things in the same order that Python finds them.
             namespaces = [ ('Interactive', self.user_ns),
                            ('Interactive (global)', self.user_global_ns),
                            ('Python builtin', builtin_mod.__dict__),
                            ]
 
         ismagic = False
         isalias = False
         found = False
         ospace = None
         parent = None
         obj = None
 
 
         # Look for the given name by splitting it in parts.  If the head is
         # found, then we look for all the remaining parts as members, and only
         # declare success if we can find them all.
         oname_parts = parts
         oname_head, oname_rest = oname_parts[0],oname_parts[1:]
         for nsname,ns in namespaces:
             try:
                 obj = ns[oname_head]
             except KeyError:
                 continue
             else:
                 for idx, part in enumerate(oname_rest):
                     try:
                         parent = obj
                         # The last part is looked up in a special way to avoid
                         # descriptor invocation as it may raise or have side
                         # effects.
                         if idx == len(oname_rest) - 1:
                             obj = self._getattr_property(obj, part)
                         else:
                             if is_integer_string(part):
                                 obj = obj[int(part)]
                             else:
                                 obj = getattr(obj, part)
                     except:
                         # Blanket except b/c some badly implemented objects
                         # allow __getattr__ to raise exceptions other than
                         # AttributeError, which then crashes IPython.
                         break
                 else:
                     # If we finish the for loop (no break), we got all members
                     found = True
                     ospace = nsname
                     break  # namespace loop
 
         # Try to see if it's magic
         if not found:
             obj = None
             if oname.startswith(ESC_MAGIC2):
                 oname = oname.lstrip(ESC_MAGIC2)
                 obj = self.find_cell_magic(oname)
             elif oname.startswith(ESC_MAGIC):
                 oname = oname.lstrip(ESC_MAGIC)
                 obj = self.find_line_magic(oname)
             else:
                 # search without prefix, so run? will find %run?
                 obj = self.find_line_magic(oname)
                 if obj is None:
                     obj = self.find_cell_magic(oname)
             if obj is not None:
                 found = True
                 ospace = 'IPython internal'
                 ismagic = True
                 isalias = isinstance(obj, Alias)
 
         # Last try: special-case some literals like '', [], {}, etc:
         if not found and oname_head in ["''",'""','[]','{}','()']:
             obj = eval(oname_head)
             found = True
             ospace = 'Interactive'
 
         return OInfo(
             obj=obj,
             found=found,
             parent=parent,
             ismagic=ismagic,
             isalias=isalias,
             namespace=ospace,
         )
 
     @staticmethod
     def _getattr_property(obj, attrname):
         """Property-aware getattr to use in object finding.
 
         If attrname represents a property, return it unevaluated (in case it has
         side effects or raises an error.
 
         """
         if not isinstance(obj, type):
             try:
                 # `getattr(type(obj), attrname)` is not guaranteed to return
                 # `obj`, but does so for property:
                 #
                 # property.__get__(self, None, cls) -> self
                 #
                 # The universal alternative is to traverse the mro manually
                 # searching for attrname in class dicts.
                 if is_integer_string(attrname):
                     return obj[int(attrname)]
                 else:
                     attr = getattr(type(obj), attrname)
             except AttributeError:
                 pass
             else:
                 # This relies on the fact that data descriptors (with both
                 # __get__ & __set__ magic methods) take precedence over
                 # instance-level attributes:
                 #
                 #    class A(object):
                 #        @property
                 #        def foobar(self): return 123
                 #    a = A()
                 #    a.__dict__['foobar'] = 345
                 #    a.foobar  # == 123
                 #
                 # So, a property may be returned right away.
                 if isinstance(attr, property):
                     return attr
 
         # Nothing helped, fall back.
         return getattr(obj, attrname)
 
     def _object_find(self, oname, namespaces=None) -> OInfo:
         """Find an object and return a struct with info about it."""
         return self._ofind(oname, namespaces)
 
-    def _inspect(self, meth, oname, namespaces=None, **kw):
+    def _inspect(self, meth, oname: str, namespaces=None, **kw):
         """Generic interface to the inspector system.
 
         This function is meant to be called by pdef, pdoc & friends.
         """
         info: OInfo = self._object_find(oname, namespaces)
         if self.sphinxify_docstring:
             if sphinxify is None:
                 raise ImportError("Module ``docrepr`` required but missing")
             docformat = sphinxify(self.object_inspect(oname))
         else:
             docformat = None
         if info.found or hasattr(info.parent, oinspect.HOOK_NAME):
             pmethod = getattr(self.inspector, meth)
             # TODO: only apply format_screen to the plain/text repr of the mime
             # bundle.
             formatter = format_screen if info.ismagic else docformat
             if meth == 'pdoc':
                 pmethod(info.obj, oname, formatter)
             elif meth == 'pinfo':
                 pmethod(
                     info.obj,
                     oname,
                     formatter,
                     info,
                     enable_html_pager=self.enable_html_pager,
                     **kw,
                 )
             else:
                 pmethod(info.obj, oname)
         else:
             print('Object `%s` not found.' % oname)
             return 'not found'  # so callers can take other action
 
     def object_inspect(self, oname, detail_level=0):
         """Get object info about oname"""
         with self.builtin_trap:
             info = self._object_find(oname)
             if info.found:
                 return self.inspector.info(info.obj, oname, info=info,
                             detail_level=detail_level
                 )
             else:
                 return oinspect.object_info(name=oname, found=False)
 
     def object_inspect_text(self, oname, detail_level=0):
         """Get object info as formatted text"""
         return self.object_inspect_mime(oname, detail_level)['text/plain']
 
     def object_inspect_mime(self, oname, detail_level=0, omit_sections=()):
         """Get object info as a mimebundle of formatted representations.
 
         A mimebundle is a dictionary, keyed by mime-type.
         It must always have the key `'text/plain'`.
         """
         with self.builtin_trap:
             info = self._object_find(oname)
             if info.found:
                 docformat = (
                     sphinxify(self.object_inspect(oname))
                     if self.sphinxify_docstring
                     else None
                 )
                 return self.inspector._get_info(
                     info.obj,
                     oname,
                     info=info,
                     detail_level=detail_level,
                     formatter=docformat,
                     omit_sections=omit_sections,
                 )
             else:
                 raise KeyError(oname)
 
     #-------------------------------------------------------------------------
     # Things related to history management
     #-------------------------------------------------------------------------
 
     def init_history(self):
         """Sets up the command history, and starts regular autosaves."""
         self.history_manager = HistoryManager(shell=self, parent=self)
         self.configurables.append(self.history_manager)
 
     #-------------------------------------------------------------------------
     # Things related to exception handling and tracebacks (not debugging)
     #-------------------------------------------------------------------------
 
     debugger_cls = InterruptiblePdb
 
     def init_traceback_handlers(self, custom_exceptions):
         # Syntax error handler.
         self.SyntaxTB = ultratb.SyntaxTB(color_scheme='NoColor', parent=self)
 
         # The interactive one is initialized with an offset, meaning we always
         # want to remove the topmost item in the traceback, which is our own
         # internal code. Valid modes: ['Plain','Context','Verbose','Minimal']
         self.InteractiveTB = ultratb.AutoFormattedTB(mode = 'Plain',
                                                      color_scheme='NoColor',
                                                      tb_offset = 1,
                                    debugger_cls=self.debugger_cls, parent=self)
 
         # The instance will store a pointer to the system-wide exception hook,
         # so that runtime code (such as magics) can access it.  This is because
         # during the read-eval loop, it may get temporarily overwritten.
         self.sys_excepthook = sys.excepthook
 
         # and add any custom exception handlers the user may have specified
         self.set_custom_exc(*custom_exceptions)
 
         # Set the exception mode
         self.InteractiveTB.set_mode(mode=self.xmode)
 
     def set_custom_exc(self, exc_tuple, handler):
         """set_custom_exc(exc_tuple, handler)
 
         Set a custom exception handler, which will be called if any of the
         exceptions in exc_tuple occur in the mainloop (specifically, in the
         run_code() method).
 
         Parameters
         ----------
         exc_tuple : tuple of exception classes
             A *tuple* of exception classes, for which to call the defined
             handler.  It is very important that you use a tuple, and NOT A
             LIST here, because of the way Python's except statement works.  If
             you only want to trap a single exception, use a singleton tuple::
 
                 exc_tuple == (MyCustomException,)
 
         handler : callable
             handler must have the following signature::
 
                 def my_handler(self, etype, value, tb, tb_offset=None):
                     ...
                     return structured_traceback
 
             Your handler must return a structured traceback (a list of strings),
             or None.
 
             This will be made into an instance method (via types.MethodType)
             of IPython itself, and it will be called if any of the exceptions
             listed in the exc_tuple are caught. If the handler is None, an
             internal basic one is used, which just prints basic info.
 
             To protect IPython from crashes, if your handler ever raises an
             exception or returns an invalid result, it will be immediately
             disabled.
 
         Notes
         -----
         WARNING: by putting in your own exception handler into IPython's main
         execution loop, you run a very good chance of nasty crashes.  This
         facility should only be used if you really know what you are doing.
         """
 
         if not isinstance(exc_tuple, tuple):
             raise TypeError("The custom exceptions must be given as a tuple.")
 
         def dummy_handler(self, etype, value, tb, tb_offset=None):
             print('*** Simple custom exception handler ***')
             print('Exception type :', etype)
             print('Exception value:', value)
             print('Traceback      :', tb)
 
         def validate_stb(stb):
             """validate structured traceback return type
 
             return type of CustomTB *should* be a list of strings, but allow
             single strings or None, which are harmless.
 
             This function will *always* return a list of strings,
             and will raise a TypeError if stb is inappropriate.
             """
             msg = "CustomTB must return list of strings, not %r" % stb
             if stb is None:
                 return []
             elif isinstance(stb, str):
                 return [stb]
             elif not isinstance(stb, list):
                 raise TypeError(msg)
             # it's a list
             for line in stb:
                 # check every element
                 if not isinstance(line, str):
                     raise TypeError(msg)
             return stb
 
         if handler is None:
             wrapped = dummy_handler
         else:
             def wrapped(self,etype,value,tb,tb_offset=None):
                 """wrap CustomTB handler, to protect IPython from user code
 
                 This makes it harder (but not impossible) for custom exception
                 handlers to crash IPython.
                 """
                 try:
                     stb = handler(self,etype,value,tb,tb_offset=tb_offset)
                     return validate_stb(stb)
                 except:
                     # clear custom handler immediately
                     self.set_custom_exc((), None)
                     print("Custom TB Handler failed, unregistering", file=sys.stderr)
                     # show the exception in handler first
                     stb = self.InteractiveTB.structured_traceback(*sys.exc_info())
                     print(self.InteractiveTB.stb2text(stb))
                     print("The original exception:")
                     stb = self.InteractiveTB.structured_traceback(
                                             (etype,value,tb), tb_offset=tb_offset
                     )
                 return stb
 
         self.CustomTB = types.MethodType(wrapped,self)
         self.custom_exceptions = exc_tuple
 
     def excepthook(self, etype, value, tb):
         """One more defense for GUI apps that call sys.excepthook.
 
         GUI frameworks like wxPython trap exceptions and call
         sys.excepthook themselves.  I guess this is a feature that
         enables them to keep running after exceptions that would
         otherwise kill their mainloop. This is a bother for IPython
         which expects to catch all of the program exceptions with a try:
         except: statement.
 
         Normally, IPython sets sys.excepthook to a CrashHandler instance, so if
         any app directly invokes sys.excepthook, it will look to the user like
         IPython crashed.  In order to work around this, we can disable the
         CrashHandler and replace it with this excepthook instead, which prints a
         regular traceback using our InteractiveTB.  In this fashion, apps which
         call sys.excepthook will generate a regular-looking exception from
         IPython, and the CrashHandler will only be triggered by real IPython
         crashes.
 
         This hook should be used sparingly, only in places which are not likely
         to be true IPython errors.
         """
         self.showtraceback((etype, value, tb), tb_offset=0)
 
     def _get_exc_info(self, exc_tuple=None):
         """get exc_info from a given tuple, sys.exc_info() or sys.last_type etc.
 
         Ensures sys.last_type,value,traceback hold the exc_info we found,
         from whichever source.
 
         raises ValueError if none of these contain any information
         """
         if exc_tuple is None:
             etype, value, tb = sys.exc_info()
         else:
             etype, value, tb = exc_tuple
 
         if etype is None:
             if hasattr(sys, 'last_type'):
                 etype, value, tb = sys.last_type, sys.last_value, \
                                    sys.last_traceback
 
         if etype is None:
             raise ValueError("No exception to find")
 
         # Now store the exception info in sys.last_type etc.
         # WARNING: these variables are somewhat deprecated and not
         # necessarily safe to use in a threaded environment, but tools
         # like pdb depend on their existence, so let's set them.  If we
         # find problems in the field, we'll need to revisit their use.
         sys.last_type = etype
         sys.last_value = value
         sys.last_traceback = tb
 
         return etype, value, tb
 
     def show_usage_error(self, exc):
         """Show a short message for UsageErrors
 
         These are special exceptions that shouldn't show a traceback.
         """
         print("UsageError: %s" % exc, file=sys.stderr)
 
     def get_exception_only(self, exc_tuple=None):
         """
         Return as a string (ending with a newline) the exception that
         just occurred, without any traceback.
         """
         etype, value, tb = self._get_exc_info(exc_tuple)
         msg = traceback.format_exception_only(etype, value)
         return ''.join(msg)
 
     def showtraceback(self, exc_tuple=None, filename=None, tb_offset=None,
                       exception_only=False, running_compiled_code=False):
         """Display the exception that just occurred.
 
         If nothing is known about the exception, this is the method which
         should be used throughout the code for presenting user tracebacks,
         rather than directly invoking the InteractiveTB object.
 
         A specific showsyntaxerror() also exists, but this method can take
         care of calling it if needed, so unless you are explicitly catching a
         SyntaxError exception, don't try to analyze the stack manually and
         simply call this method."""
 
         try:
             try:
                 etype, value, tb = self._get_exc_info(exc_tuple)
             except ValueError:
                 print('No traceback available to show.', file=sys.stderr)
                 return
 
             if issubclass(etype, SyntaxError):
                 # Though this won't be called by syntax errors in the input
                 # line, there may be SyntaxError cases with imported code.
                 self.showsyntaxerror(filename, running_compiled_code)
             elif etype is UsageError:
                 self.show_usage_error(value)
             else:
                 if exception_only:
                     stb = ['An exception has occurred, use %tb to see '
                            'the full traceback.\n']
                     stb.extend(self.InteractiveTB.get_exception_only(etype,
                                                                      value))
                 else:
 
                     def contains_exceptiongroup(val):
                         if val is None:
                             return False
                         return isinstance(
                             val, BaseExceptionGroup
                         ) or contains_exceptiongroup(val.__context__)
 
                     if contains_exceptiongroup(value):
                         # fall back to native exception formatting until ultratb
                         # supports exception groups
                         traceback.print_exc()
                     else:
                         try:
                             # Exception classes can customise their traceback - we
                             # use this in IPython.parallel for exceptions occurring
                             # in the engines. This should return a list of strings.
                             if hasattr(value, "_render_traceback_"):
                                 stb = value._render_traceback_()
                             else:
                                 stb = self.InteractiveTB.structured_traceback(
                                     etype, value, tb, tb_offset=tb_offset
                                 )
 
                         except Exception:
                             print(
                                 "Unexpected exception formatting exception. Falling back to standard exception"
                             )
                             traceback.print_exc()
                             return None
 
                         self._showtraceback(etype, value, stb)
                     if self.call_pdb:
                         # drop into debugger
                         self.debugger(force=True)
                     return
 
                 # Actually show the traceback
                 self._showtraceback(etype, value, stb)
 
         except KeyboardInterrupt:
             print('\n' + self.get_exception_only(), file=sys.stderr)
 
     def _showtraceback(self, etype, evalue, stb: str):
         """Actually show a traceback.
 
         Subclasses may override this method to put the traceback on a different
         place, like a side channel.
         """
         val = self.InteractiveTB.stb2text(stb)
         try:
             print(val)
         except UnicodeEncodeError:
             print(val.encode("utf-8", "backslashreplace").decode())
 
     def showsyntaxerror(self, filename=None, running_compiled_code=False):
         """Display the syntax error that just occurred.
 
         This doesn't display a stack trace because there isn't one.
 
         If a filename is given, it is stuffed in the exception instead
         of what was there before (because Python's parser always uses
         "<string>" when reading from a string).
 
         If the syntax error occurred when running a compiled code (i.e. running_compile_code=True),
         longer stack trace will be displayed.
         """
         etype, value, last_traceback = self._get_exc_info()
 
         if filename and issubclass(etype, SyntaxError):
             try:
                 value.filename = filename
             except:
                 # Not the format we expect; leave it alone
                 pass
 
         # If the error occurred when executing compiled code, we should provide full stacktrace.
         elist = traceback.extract_tb(last_traceback) if running_compiled_code else []
         stb = self.SyntaxTB.structured_traceback(etype, value, elist)
         self._showtraceback(etype, value, stb)
 
     # This is overridden in TerminalInteractiveShell to show a message about
     # the %paste magic.
     def showindentationerror(self):
         """Called by _run_cell when there's an IndentationError in code entered
         at the prompt.
 
         This is overridden in TerminalInteractiveShell to show a message about
         the %paste magic."""
         self.showsyntaxerror()
 
     @skip_doctest
     def set_next_input(self, s, replace=False):
         """ Sets the 'default' input string for the next command line.
 
         Example::
 
             In [1]: _ip.set_next_input("Hello Word")
             In [2]: Hello Word_  # cursor is here
         """
         self.rl_next_input = s
 
     def _indent_current_str(self):
         """return the current level of indentation as a string"""
         return self.input_splitter.get_indent_spaces() * ' '
 
     #-------------------------------------------------------------------------
     # Things related to text completion
     #-------------------------------------------------------------------------
 
     def init_completer(self):
         """Initialize the completion machinery.
 
         This creates completion machinery that can be used by client code,
         either interactively in-process (typically triggered by the readline
         library), programmatically (such as in test suites) or out-of-process
         (typically over the network by remote frontends).
         """
         from IPython.core.completer import IPCompleter
         from IPython.core.completerlib import (
             cd_completer,
             magic_run_completer,
             module_completer,
             reset_completer,
         )
 
         self.Completer = IPCompleter(shell=self,
                                      namespace=self.user_ns,
                                      global_namespace=self.user_global_ns,
                                      parent=self,
                                      )
         self.configurables.append(self.Completer)
 
         # Add custom completers to the basic ones built into IPCompleter
         sdisp = self.strdispatchers.get('complete_command', StrDispatch())
         self.strdispatchers['complete_command'] = sdisp
         self.Completer.custom_completers = sdisp
 
         self.set_hook('complete_command', module_completer, str_key = 'import')
         self.set_hook('complete_command', module_completer, str_key = 'from')
         self.set_hook('complete_command', module_completer, str_key = '%aimport')
         self.set_hook('complete_command', magic_run_completer, str_key = '%run')
         self.set_hook('complete_command', cd_completer, str_key = '%cd')
         self.set_hook('complete_command', reset_completer, str_key = '%reset')
 
     @skip_doctest
     def complete(self, text, line=None, cursor_pos=None):
         """Return the completed text and a list of completions.
 
         Parameters
         ----------
         text : string
             A string of text to be completed on.  It can be given as empty and
             instead a line/position pair are given.  In this case, the
             completer itself will split the line like readline does.
         line : string, optional
             The complete line that text is part of.
         cursor_pos : int, optional
             The position of the cursor on the input line.
 
         Returns
         -------
         text : string
             The actual text that was completed.
         matches : list
             A sorted list with all possible completions.
 
         Notes
         -----
         The optional arguments allow the completion to take more context into
         account, and are part of the low-level completion API.
 
         This is a wrapper around the completion mechanism, similar to what
         readline does at the command line when the TAB key is hit.  By
         exposing it as a method, it can be used by other non-readline
         environments (such as GUIs) for text completion.
 
         Examples
         --------
         In [1]: x = 'hello'
 
         In [2]: _ip.complete('x.l')
         Out[2]: ('x.l', ['x.ljust', 'x.lower', 'x.lstrip'])
         """
 
         # Inject names into __builtin__ so we can complete on the added names.
         with self.builtin_trap:
             return self.Completer.complete(text, line, cursor_pos)
 
     def set_custom_completer(self, completer, pos=0) -> None:
         """Adds a new custom completer function.
 
         The position argument (defaults to 0) is the index in the completers
         list where you want the completer to be inserted.
 
         `completer` should have the following signature::
 
             def completion(self: Completer, text: string) -> List[str]:
                 raise NotImplementedError
 
         It will be bound to the current Completer instance and pass some text
         and return a list with current completions to suggest to the user.
         """
 
         newcomp = types.MethodType(completer, self.Completer)
         self.Completer.custom_matchers.insert(pos,newcomp)
 
     def set_completer_frame(self, frame=None):
         """Set the frame of the completer."""
         if frame:
             self.Completer.namespace = frame.f_locals
             self.Completer.global_namespace = frame.f_globals
         else:
             self.Completer.namespace = self.user_ns
             self.Completer.global_namespace = self.user_global_ns
 
     #-------------------------------------------------------------------------
     # Things related to magics
     #-------------------------------------------------------------------------
 
     def init_magics(self):
         from IPython.core import magics as m
         self.magics_manager = magic.MagicsManager(shell=self,
                                    parent=self,
                                    user_magics=m.UserMagics(self))
         self.configurables.append(self.magics_manager)
 
         # Expose as public API from the magics manager
         self.register_magics = self.magics_manager.register
 
         self.register_magics(m.AutoMagics, m.BasicMagics, m.CodeMagics,
             m.ConfigMagics, m.DisplayMagics, m.ExecutionMagics,
             m.ExtensionMagics, m.HistoryMagics, m.LoggingMagics,
             m.NamespaceMagics, m.OSMagics, m.PackagingMagics,
             m.PylabMagics, m.ScriptMagics,
         )
         self.register_magics(m.AsyncMagics)
 
         # Register Magic Aliases
         mman = self.magics_manager
         # FIXME: magic aliases should be defined by the Magics classes
         # or in MagicsManager, not here
         mman.register_alias('ed', 'edit')
         mman.register_alias('hist', 'history')
         mman.register_alias('rep', 'recall')
         mman.register_alias('SVG', 'svg', 'cell')
         mman.register_alias('HTML', 'html', 'cell')
         mman.register_alias('file', 'writefile', 'cell')
 
         # FIXME: Move the color initialization to the DisplayHook, which
         # should be split into a prompt manager and displayhook. We probably
         # even need a centralize colors management object.
         self.run_line_magic('colors', self.colors)
 
     # Defined here so that it's included in the documentation
     @functools.wraps(magic.MagicsManager.register_function)
     def register_magic_function(self, func, magic_kind='line', magic_name=None):
         self.magics_manager.register_function(
             func, magic_kind=magic_kind, magic_name=magic_name
         )
 
     def _find_with_lazy_load(self, /, type_, magic_name: str):
         """
         Try to find a magic potentially lazy-loading it.
 
         Parameters
         ----------
 
         type_: "line"|"cell"
             the type of magics we are trying to find/lazy load.
         magic_name: str
             The name of the magic we are trying to find/lazy load
 
 
         Note that this may have any side effects
         """
         finder = {"line": self.find_line_magic, "cell": self.find_cell_magic}[type_]
         fn = finder(magic_name)
         if fn is not None:
             return fn
         lazy = self.magics_manager.lazy_magics.get(magic_name)
         if lazy is None:
             return None
 
         self.run_line_magic("load_ext", lazy)
         res = finder(magic_name)
         return res
 
-    def run_line_magic(self, magic_name: str, line, _stack_depth=1):
+    def run_line_magic(self, magic_name: str, line: str, _stack_depth=1):
         """Execute the given line magic.
 
         Parameters
         ----------
         magic_name : str
             Name of the desired magic function, without '%' prefix.
         line : str
             The rest of the input line as a single string.
         _stack_depth : int
             If run_line_magic() is called from magic() then _stack_depth=2.
             This is added to ensure backward compatibility for use of 'get_ipython().magic()'
         """
         fn = self._find_with_lazy_load("line", magic_name)
         if fn is None:
             lazy = self.magics_manager.lazy_magics.get(magic_name)
             if lazy:
                 self.run_line_magic("load_ext", lazy)
                 fn = self.find_line_magic(magic_name)
         if fn is None:
             cm = self.find_cell_magic(magic_name)
             etpl = "Line magic function `%%%s` not found%s."
             extra = '' if cm is None else (' (But cell magic `%%%%%s` exists, '
                                     'did you mean that instead?)' % magic_name )
             raise UsageError(etpl % (magic_name, extra))
         else:
             # Note: this is the distance in the stack to the user's frame.
             # This will need to be updated if the internal calling logic gets
             # refactored, or else we'll be expanding the wrong variables.
 
             # Determine stack_depth depending on where run_line_magic() has been called
             stack_depth = _stack_depth
             if getattr(fn, magic.MAGIC_NO_VAR_EXPAND_ATTR, False):
                 # magic has opted out of var_expand
                 magic_arg_s = line
             else:
                 magic_arg_s = self.var_expand(line, stack_depth)
             # Put magic args in a list so we can call with f(*a) syntax
             args = [magic_arg_s]
             kwargs = {}
             # Grab local namespace if we need it:
             if getattr(fn, "needs_local_scope", False):
                 kwargs['local_ns'] = self.get_local_scope(stack_depth)
             with self.builtin_trap:
                 result = fn(*args, **kwargs)
 
             # The code below prevents the output from being displayed
             # when using magics with decorator @output_can_be_silenced
             # when the last Python token in the expression is a ';'.
             if getattr(fn, magic.MAGIC_OUTPUT_CAN_BE_SILENCED, False):
                 if DisplayHook.semicolon_at_end_of_expression(magic_arg_s):
                     return None
 
             return result
 
     def get_local_scope(self, stack_depth):
         """Get local scope at given stack depth.
 
         Parameters
         ----------
         stack_depth : int
             Depth relative to calling frame
         """
         return sys._getframe(stack_depth + 1).f_locals
 
     def run_cell_magic(self, magic_name, line, cell):
         """Execute the given cell magic.
 
         Parameters
         ----------
         magic_name : str
             Name of the desired magic function, without '%' prefix.
         line : str
             The rest of the first input line as a single string.
         cell : str
             The body of the cell as a (possibly multiline) string.
         """
         fn = self._find_with_lazy_load("cell", magic_name)
         if fn is None:
             lm = self.find_line_magic(magic_name)
             etpl = "Cell magic `%%{0}` not found{1}."
             extra = '' if lm is None else (' (But line magic `%{0}` exists, '
                             'did you mean that instead?)'.format(magic_name))
             raise UsageError(etpl.format(magic_name, extra))
         elif cell == '':
             message = '%%{0} is a cell magic, but the cell body is empty.'.format(magic_name)
             if self.find_line_magic(magic_name) is not None:
                 message += ' Did you mean the line magic %{0} (single %)?'.format(magic_name)
             raise UsageError(message)
         else:
             # Note: this is the distance in the stack to the user's frame.
             # This will need to be updated if the internal calling logic gets
             # refactored, or else we'll be expanding the wrong variables.
             stack_depth = 2
             if getattr(fn, magic.MAGIC_NO_VAR_EXPAND_ATTR, False):
                 # magic has opted out of var_expand
                 magic_arg_s = line
             else:
                 magic_arg_s = self.var_expand(line, stack_depth)
             kwargs = {}
             if getattr(fn, "needs_local_scope", False):
                 kwargs['local_ns'] = self.user_ns
 
             with self.builtin_trap:
                 args = (magic_arg_s, cell)
                 result = fn(*args, **kwargs)
 
             # The code below prevents the output from being displayed
             # when using magics with decorator @output_can_be_silenced
             # when the last Python token in the expression is a ';'.
             if getattr(fn, magic.MAGIC_OUTPUT_CAN_BE_SILENCED, False):
                 if DisplayHook.semicolon_at_end_of_expression(cell):
                     return None
 
             return result
 
     def find_line_magic(self, magic_name):
         """Find and return a line magic by name.
 
         Returns None if the magic isn't found."""
         return self.magics_manager.magics['line'].get(magic_name)
 
     def find_cell_magic(self, magic_name):
         """Find and return a cell magic by name.
 
         Returns None if the magic isn't found."""
         return self.magics_manager.magics['cell'].get(magic_name)
 
     def find_magic(self, magic_name, magic_kind='line'):
         """Find and return a magic of the given type by name.
 
         Returns None if the magic isn't found."""
         return self.magics_manager.magics[magic_kind].get(magic_name)
 
     def magic(self, arg_s):
         """
         DEPRECATED
 
         Deprecated since IPython 0.13 (warning added in
         8.1), use run_line_magic(magic_name, parameter_s).
 
         Call a magic function by name.
 
         Input: a string containing the name of the magic function to call and
         any additional arguments to be passed to the magic.
 
         magic('name -opt foo bar') is equivalent to typing at the ipython
         prompt:
 
         In[1]: %name -opt foo bar
 
         To call a magic without arguments, simply use magic('name').
 
         This provides a proper Python function to call IPython's magics in any
         valid Python code you can type at the interpreter, including loops and
         compound statements.
         """
         warnings.warn(
             "`magic(...)` is deprecated since IPython 0.13 (warning added in "
             "8.1), use run_line_magic(magic_name, parameter_s).",
             DeprecationWarning,
             stacklevel=2,
         )
         # TODO: should we issue a loud deprecation warning here?
         magic_name, _, magic_arg_s = arg_s.partition(' ')
         magic_name = magic_name.lstrip(prefilter.ESC_MAGIC)
         return self.run_line_magic(magic_name, magic_arg_s, _stack_depth=2)
 
     #-------------------------------------------------------------------------
     # Things related to macros
     #-------------------------------------------------------------------------
 
     def define_macro(self, name, themacro):
         """Define a new macro
 
         Parameters
         ----------
         name : str
             The name of the macro.
         themacro : str or Macro
             The action to do upon invoking the macro.  If a string, a new
             Macro object is created by passing the string to it.
         """
 
         from IPython.core import macro
 
         if isinstance(themacro, str):
             themacro = macro.Macro(themacro)
         if not isinstance(themacro, macro.Macro):
             raise ValueError('A macro must be a string or a Macro instance.')
         self.user_ns[name] = themacro
 
     #-------------------------------------------------------------------------
     # Things related to the running of system commands
     #-------------------------------------------------------------------------
 
     def system_piped(self, cmd):
         """Call the given cmd in a subprocess, piping stdout/err
 
         Parameters
         ----------
         cmd : str
             Command to execute (can not end in '&', as background processes are
             not supported.  Should not be a command that expects input
             other than simple text.
         """
         if cmd.rstrip().endswith('&'):
             # this is *far* from a rigorous test
             # We do not support backgrounding processes because we either use
             # pexpect or pipes to read from.  Users can always just call
             # os.system() or use ip.system=ip.system_raw
             # if they really want a background process.
             raise OSError("Background processes not supported.")
 
         # we explicitly do NOT return the subprocess status code, because
         # a non-None value would trigger :func:`sys.displayhook` calls.
         # Instead, we store the exit_code in user_ns.
         self.user_ns['_exit_code'] = system(self.var_expand(cmd, depth=1))
 
     def system_raw(self, cmd):
         """Call the given cmd in a subprocess using os.system on Windows or
         subprocess.call using the system shell on other platforms.
 
         Parameters
         ----------
         cmd : str
             Command to execute.
         """
         cmd = self.var_expand(cmd, depth=1)
         # warn if there is an IPython magic alternative.
         if cmd == "":
             main_cmd = ""
         else:
             main_cmd = cmd.split()[0]
         has_magic_alternatives = ("pip", "conda", "cd")
 
         if main_cmd in has_magic_alternatives:
             warnings.warn(
                 (
                     "You executed the system command !{0} which may not work "
                     "as expected. Try the IPython magic %{0} instead."
                 ).format(main_cmd)
             )
 
         # protect os.system from UNC paths on Windows, which it can't handle:
         if sys.platform == 'win32':
             from IPython.utils._process_win32 import AvoidUNCPath
             with AvoidUNCPath() as path:
                 if path is not None:
                     cmd = '"pushd %s &&"%s' % (path, cmd)
                 try:
                     ec = os.system(cmd)
                 except KeyboardInterrupt:
                     print('\n' + self.get_exception_only(), file=sys.stderr)
                     ec = -2
         else:
             # For posix the result of the subprocess.call() below is an exit
             # code, which by convention is zero for success, positive for
             # program failure.  Exit codes above 128 are reserved for signals,
             # and the formula for converting a signal to an exit code is usually
             # signal_number+128.  To more easily differentiate between exit
             # codes and signals, ipython uses negative numbers.  For instance
             # since control-c is signal 2 but exit code 130, ipython's
             # _exit_code variable will read -2.  Note that some shells like
             # csh and fish don't follow sh/bash conventions for exit codes.
             executable = os.environ.get('SHELL', None)
             try:
                 # Use env shell instead of default /bin/sh
                 ec = subprocess.call(cmd, shell=True, executable=executable)
             except KeyboardInterrupt:
                 # intercept control-C; a long traceback is not useful here
                 print('\n' + self.get_exception_only(), file=sys.stderr)
                 ec = 130
             if ec > 128:
                 ec = -(ec - 128)
 
         # We explicitly do NOT return the subprocess status code, because
         # a non-None value would trigger :func:`sys.displayhook` calls.
         # Instead, we store the exit_code in user_ns.  Note the semantics
         # of _exit_code: for control-c, _exit_code == -signal.SIGNIT,
         # but raising SystemExit(_exit_code) will give status 254!
         self.user_ns['_exit_code'] = ec
 
     # use piped system by default, because it is better behaved
     system = system_piped
 
     def getoutput(self, cmd, split=True, depth=0):
         """Get output (possibly including stderr) from a subprocess.
 
         Parameters
         ----------
         cmd : str
             Command to execute (can not end in '&', as background processes are
             not supported.
         split : bool, optional
             If True, split the output into an IPython SList.  Otherwise, an
             IPython LSString is returned.  These are objects similar to normal
             lists and strings, with a few convenience attributes for easier
             manipulation of line-based output.  You can use '?' on them for
             details.
         depth : int, optional
             How many frames above the caller are the local variables which should
             be expanded in the command string? The default (0) assumes that the
             expansion variables are in the stack frame calling this function.
         """
         if cmd.rstrip().endswith('&'):
             # this is *far* from a rigorous test
             raise OSError("Background processes not supported.")
         out = getoutput(self.var_expand(cmd, depth=depth+1))
         if split:
             out = SList(out.splitlines())
         else:
             out = LSString(out)
         return out
 
     #-------------------------------------------------------------------------
     # Things related to aliases
     #-------------------------------------------------------------------------
 
     def init_alias(self):
         self.alias_manager = AliasManager(shell=self, parent=self)
         self.configurables.append(self.alias_manager)
 
     #-------------------------------------------------------------------------
     # Things related to extensions
     #-------------------------------------------------------------------------
 
     def init_extension_manager(self):
         self.extension_manager = ExtensionManager(shell=self, parent=self)
         self.configurables.append(self.extension_manager)
 
     #-------------------------------------------------------------------------
     # Things related to payloads
     #-------------------------------------------------------------------------
 
     def init_payload(self):
         self.payload_manager = PayloadManager(parent=self)
         self.configurables.append(self.payload_manager)
 
     #-------------------------------------------------------------------------
     # Things related to the prefilter
     #-------------------------------------------------------------------------
 
     def init_prefilter(self):
         self.prefilter_manager = PrefilterManager(shell=self, parent=self)
         self.configurables.append(self.prefilter_manager)
         # Ultimately this will be refactored in the new interpreter code, but
         # for now, we should expose the main prefilter method (there's legacy
         # code out there that may rely on this).
         self.prefilter = self.prefilter_manager.prefilter_lines
 
     def auto_rewrite_input(self, cmd):
         """Print to the screen the rewritten form of the user's command.
 
         This shows visual feedback by rewriting input lines that cause
         automatic calling to kick in, like::
 
           /f x
 
         into::
 
           ------> f(x)
 
         after the user's input prompt.  This helps the user understand that the
         input line was transformed automatically by IPython.
         """
         if not self.show_rewritten_input:
             return
 
         # This is overridden in TerminalInteractiveShell to use fancy prompts
         print("------> " + cmd)
 
     #-------------------------------------------------------------------------
     # Things related to extracting values/expressions from kernel and user_ns
     #-------------------------------------------------------------------------
 
     def _user_obj_error(self):
         """return simple exception dict
 
         for use in user_expressions
         """
 
         etype, evalue, tb = self._get_exc_info()
         stb = self.InteractiveTB.get_exception_only(etype, evalue)
 
         exc_info = {
             "status": "error",
             "traceback": stb,
             "ename": etype.__name__,
             "evalue": py3compat.safe_unicode(evalue),
         }
 
         return exc_info
 
     def _format_user_obj(self, obj):
         """format a user object to display dict
 
         for use in user_expressions
         """
 
         data, md = self.display_formatter.format(obj)
         value = {
             'status' : 'ok',
             'data' : data,
             'metadata' : md,
         }
         return value
 
     def user_expressions(self, expressions):
         """Evaluate a dict of expressions in the user's namespace.
 
         Parameters
         ----------
         expressions : dict
             A dict with string keys and string values.  The expression values
             should be valid Python expressions, each of which will be evaluated
             in the user namespace.
 
         Returns
         -------
         A dict, keyed like the input expressions dict, with the rich mime-typed
         display_data of each value.
         """
         out = {}
         user_ns = self.user_ns
         global_ns = self.user_global_ns
 
         for key, expr in expressions.items():
             try:
                 value = self._format_user_obj(eval(expr, global_ns, user_ns))
             except:
                 value = self._user_obj_error()
             out[key] = value
         return out
 
     #-------------------------------------------------------------------------
     # Things related to the running of code
     #-------------------------------------------------------------------------
 
     def ex(self, cmd):
         """Execute a normal python statement in user namespace."""
         with self.builtin_trap:
             exec(cmd, self.user_global_ns, self.user_ns)
 
     def ev(self, expr):
         """Evaluate python expression expr in user namespace.
 
         Returns the result of evaluation
         """
         with self.builtin_trap:
             return eval(expr, self.user_global_ns, self.user_ns)
 
     def safe_execfile(self, fname, *where, exit_ignore=False, raise_exceptions=False, shell_futures=False):
         """A safe version of the builtin execfile().
 
         This version will never throw an exception, but instead print
         helpful error messages to the screen.  This only works on pure
         Python files with the .py extension.
 
         Parameters
         ----------
         fname : string
             The name of the file to be executed.
         *where : tuple
             One or two namespaces, passed to execfile() as (globals,locals).
             If only one is given, it is passed as both.
         exit_ignore : bool (False)
             If True, then silence SystemExit for non-zero status (it is always
             silenced for zero status, as it is so common).
         raise_exceptions : bool (False)
             If True raise exceptions everywhere. Meant for testing.
         shell_futures : bool (False)
             If True, the code will share future statements with the interactive
             shell. It will both be affected by previous __future__ imports, and
             any __future__ imports in the code will affect the shell. If False,
             __future__ imports are not shared in either direction.
 
         """
         fname = Path(fname).expanduser().resolve()
 
         # Make sure we can open the file
         try:
             with fname.open("rb"):
                 pass
         except:
             warn('Could not open file <%s> for safe execution.' % fname)
             return
 
         # Find things also in current directory.  This is needed to mimic the
         # behavior of running a script from the system command line, where
         # Python inserts the script's directory into sys.path
         dname = str(fname.parent)
 
         with prepended_to_syspath(dname), self.builtin_trap:
             try:
                 glob, loc = (where + (None, ))[:2]
                 py3compat.execfile(
                     fname, glob, loc,
                     self.compile if shell_futures else None)
             except SystemExit as status:
                 # If the call was made with 0 or None exit status (sys.exit(0)
                 # or sys.exit() ), don't bother showing a traceback, as both of
                 # these are considered normal by the OS:
                 # > python -c'import sys;sys.exit(0)'; echo $?
                 # 0
                 # > python -c'import sys;sys.exit()'; echo $?
                 # 0
                 # For other exit status, we show the exception unless
                 # explicitly silenced, but only in short form.
                 if status.code:
                     if raise_exceptions:
                         raise
                     if not exit_ignore:
                         self.showtraceback(exception_only=True)
             except:
                 if raise_exceptions:
                     raise
                 # tb offset is 2 because we wrap execfile
                 self.showtraceback(tb_offset=2)
 
     def safe_execfile_ipy(self, fname, shell_futures=False, raise_exceptions=False):
         """Like safe_execfile, but for .ipy or .ipynb files with IPython syntax.
 
         Parameters
         ----------
         fname : str
             The name of the file to execute.  The filename must have a
             .ipy or .ipynb extension.
         shell_futures : bool (False)
             If True, the code will share future statements with the interactive
             shell. It will both be affected by previous __future__ imports, and
             any __future__ imports in the code will affect the shell. If False,
             __future__ imports are not shared in either direction.
         raise_exceptions : bool (False)
             If True raise exceptions everywhere.  Meant for testing.
         """
         fname = Path(fname).expanduser().resolve()
 
         # Make sure we can open the file
         try:
             with fname.open("rb"):
                 pass
         except:
             warn('Could not open file <%s> for safe execution.' % fname)
             return
 
         # Find things also in current directory.  This is needed to mimic the
         # behavior of running a script from the system command line, where
         # Python inserts the script's directory into sys.path
         dname = str(fname.parent)
 
         def get_cells():
             """generator for sequence of code blocks to run"""
             if fname.suffix == ".ipynb":
                 from nbformat import read
                 nb = read(fname, as_version=4)
                 if not nb.cells:
                     return
                 for cell in nb.cells:
                     if cell.cell_type == 'code':
                         yield cell.source
             else:
                 yield fname.read_text(encoding="utf-8")
 
         with prepended_to_syspath(dname):
             try:
                 for cell in get_cells():
                     result = self.run_cell(cell, silent=True, shell_futures=shell_futures)
                     if raise_exceptions:
                         result.raise_error()
                     elif not result.success:
                         break
             except:
                 if raise_exceptions:
                     raise
                 self.showtraceback()
                 warn('Unknown failure executing file: <%s>' % fname)
 
     def safe_run_module(self, mod_name, where):
         """A safe version of runpy.run_module().
 
         This version will never throw an exception, but instead print
         helpful error messages to the screen.
 
         `SystemExit` exceptions with status code 0 or None are ignored.
 
         Parameters
         ----------
         mod_name : string
             The name of the module to be executed.
         where : dict
             The globals namespace.
         """
         try:
             try:
                 where.update(
                     runpy.run_module(str(mod_name), run_name="__main__",
                                      alter_sys=True)
                             )
             except SystemExit as status:
                 if status.code:
                     raise
         except:
             self.showtraceback()
             warn('Unknown failure executing module: <%s>' % mod_name)
 
     def run_cell(
         self,
         raw_cell,
         store_history=False,
         silent=False,
         shell_futures=True,
         cell_id=None,
     ):
         """Run a complete IPython cell.
 
         Parameters
         ----------
         raw_cell : str
             The code (including IPython code such as %magic functions) to run.
         store_history : bool
             If True, the raw and translated cell will be stored in IPython's
             history. For user code calling back into IPython's machinery, this
             should be set to False.
         silent : bool
             If True, avoid side-effects, such as implicit displayhooks and
             and logging.  silent=True forces store_history=False.
         shell_futures : bool
             If True, the code will share future statements with the interactive
             shell. It will both be affected by previous __future__ imports, and
             any __future__ imports in the code will affect the shell. If False,
             __future__ imports are not shared in either direction.
 
         Returns
         -------
         result : :class:`ExecutionResult`
         """
         result = None
         try:
             result = self._run_cell(
                 raw_cell, store_history, silent, shell_futures, cell_id
             )
         finally:
             self.events.trigger('post_execute')
             if not silent:
                 self.events.trigger('post_run_cell', result)
         return result
 
     def _run_cell(
         self,
         raw_cell: str,
         store_history: bool,
         silent: bool,
         shell_futures: bool,
         cell_id: str,
     ) -> ExecutionResult:
         """Internal method to run a complete IPython cell."""
 
         # we need to avoid calling self.transform_cell multiple time on the same thing
         # so we need to store some results:
         preprocessing_exc_tuple = None
         try:
             transformed_cell = self.transform_cell(raw_cell)
         except Exception:
             transformed_cell = raw_cell
             preprocessing_exc_tuple = sys.exc_info()
 
         assert transformed_cell is not None
         coro = self.run_cell_async(
             raw_cell,
             store_history=store_history,
             silent=silent,
             shell_futures=shell_futures,
             transformed_cell=transformed_cell,
             preprocessing_exc_tuple=preprocessing_exc_tuple,
             cell_id=cell_id,
         )
 
         # run_cell_async is async, but may not actually need an eventloop.
         # when this is the case, we want to run it using the pseudo_sync_runner
         # so that code can invoke eventloops (for example via the %run , and
         # `%paste` magic.
         if self.trio_runner:
             runner = self.trio_runner
         elif self.should_run_async(
             raw_cell,
             transformed_cell=transformed_cell,
             preprocessing_exc_tuple=preprocessing_exc_tuple,
         ):
             runner = self.loop_runner
         else:
             runner = _pseudo_sync_runner
 
         try:
             result = runner(coro)
         except BaseException as e:
             info = ExecutionInfo(
                 raw_cell, store_history, silent, shell_futures, cell_id
             )
             result = ExecutionResult(info)
             result.error_in_exec = e
             self.showtraceback(running_compiled_code=True)
         finally:
             return result
 
     def should_run_async(
         self, raw_cell: str, *, transformed_cell=None, preprocessing_exc_tuple=None
     ) -> bool:
         """Return whether a cell should be run asynchronously via a coroutine runner
 
         Parameters
         ----------
         raw_cell : str
             The code to be executed
 
         Returns
         -------
         result: bool
             Whether the code needs to be run with a coroutine runner or not
         .. versionadded:: 7.0
         """
         if not self.autoawait:
             return False
         if preprocessing_exc_tuple is not None:
             return False
         assert preprocessing_exc_tuple is None
         if transformed_cell is None:
             warnings.warn(
                 "`should_run_async` will not call `transform_cell`"
                 " automatically in the future. Please pass the result to"
                 " `transformed_cell` argument and any exception that happen"
                 " during the"
                 "transform in `preprocessing_exc_tuple` in"
                 " IPython 7.17 and above.",
                 DeprecationWarning,
                 stacklevel=2,
             )
             try:
                 cell = self.transform_cell(raw_cell)
             except Exception:
                 # any exception during transform will be raised
                 # prior to execution
                 return False
         else:
             cell = transformed_cell
         return _should_be_async(cell)
 
     async def run_cell_async(
         self,
         raw_cell: str,
         store_history=False,
         silent=False,
         shell_futures=True,
         *,
         transformed_cell: Optional[str] = None,
         preprocessing_exc_tuple: Optional[AnyType] = None,
         cell_id=None,
     ) -> ExecutionResult:
         """Run a complete IPython cell asynchronously.
 
         Parameters
         ----------
         raw_cell : str
           The code (including IPython code such as %magic functions) to run.
         store_history : bool
           If True, the raw and translated cell will be stored in IPython's
           history. For user code calling back into IPython's machinery, this
           should be set to False.
         silent : bool
           If True, avoid side-effects, such as implicit displayhooks and
           and logging.  silent=True forces store_history=False.
         shell_futures : bool
           If True, the code will share future statements with the interactive
           shell. It will both be affected by previous __future__ imports, and
           any __future__ imports in the code will affect the shell. If False,
           __future__ imports are not shared in either direction.
         transformed_cell: str
           cell that was passed through transformers
         preprocessing_exc_tuple:
           trace if the transformation failed.
 
         Returns
         -------
         result : :class:`ExecutionResult`
 
         .. versionadded:: 7.0
         """
         info = ExecutionInfo(raw_cell, store_history, silent, shell_futures, cell_id)
         result = ExecutionResult(info)
 
         if (not raw_cell) or raw_cell.isspace():
             self.last_execution_succeeded = True
             self.last_execution_result = result
             return result
 
         if silent:
             store_history = False
 
         if store_history:
             result.execution_count = self.execution_count
 
         def error_before_exec(value):
             if store_history:
                 self.execution_count += 1
             result.error_before_exec = value
             self.last_execution_succeeded = False
             self.last_execution_result = result
             return result
 
         self.events.trigger('pre_execute')
         if not silent:
             self.events.trigger('pre_run_cell', info)
 
         if transformed_cell is None:
             warnings.warn(
                 "`run_cell_async` will not call `transform_cell`"
                 " automatically in the future. Please pass the result to"
                 " `transformed_cell` argument and any exception that happen"
                 " during the"
                 "transform in `preprocessing_exc_tuple` in"
                 " IPython 7.17 and above.",
                 DeprecationWarning,
                 stacklevel=2,
             )
             # If any of our input transformation (input_transformer_manager or
             # prefilter_manager) raises an exception, we store it in this variable
             # so that we can display the error after logging the input and storing
             # it in the history.
             try:
                 cell = self.transform_cell(raw_cell)
             except Exception:
                 preprocessing_exc_tuple = sys.exc_info()
                 cell = raw_cell  # cell has to exist so it can be stored/logged
             else:
                 preprocessing_exc_tuple = None
         else:
             if preprocessing_exc_tuple is None:
                 cell = transformed_cell
             else:
                 cell = raw_cell
 
         # Do NOT store paste/cpaste magic history
         if "get_ipython().run_line_magic(" in cell and "paste" in cell:
             store_history = False
 
         # Store raw and processed history
         if store_history:
+            assert self.history_manager is not None
             self.history_manager.store_inputs(self.execution_count, cell, raw_cell)
         if not silent:
             self.logger.log(cell, raw_cell)
 
         # Display the exception if input processing failed.
         if preprocessing_exc_tuple is not None:
             self.showtraceback(preprocessing_exc_tuple)
             if store_history:
                 self.execution_count += 1
             return error_before_exec(preprocessing_exc_tuple[1])
 
         # Our own compiler remembers the __future__ environment. If we want to
         # run code with a separate __future__ environment, use the default
         # compiler
         compiler = self.compile if shell_futures else self.compiler_class()
 
-        _run_async = False
-
         with self.builtin_trap:
             cell_name = compiler.cache(cell, self.execution_count, raw_code=raw_cell)
 
             with self.display_trap:
                 # Compile to bytecode
                 try:
                     code_ast = compiler.ast_parse(cell, filename=cell_name)
                 except self.custom_exceptions as e:
                     etype, value, tb = sys.exc_info()
                     self.CustomTB(etype, value, tb)
                     return error_before_exec(e)
                 except IndentationError as e:
                     self.showindentationerror()
                     return error_before_exec(e)
                 except (OverflowError, SyntaxError, ValueError, TypeError,
                         MemoryError) as e:
                     self.showsyntaxerror()
                     return error_before_exec(e)
 
                 # Apply AST transformations
                 try:
                     code_ast = self.transform_ast(code_ast)
                 except InputRejected as e:
                     self.showtraceback()
                     return error_before_exec(e)
 
                 # Give the displayhook a reference to our ExecutionResult so it
                 # can fill in the output value.
                 self.displayhook.exec_result = result
 
                 # Execute the user code
                 interactivity = "none" if silent else self.ast_node_interactivity
 
 
                 has_raised = await self.run_ast_nodes(code_ast.body, cell_name,
                        interactivity=interactivity, compiler=compiler, result=result)
 
                 self.last_execution_succeeded = not has_raised
                 self.last_execution_result = result
 
                 # Reset this so later displayed values do not modify the
                 # ExecutionResult
                 self.displayhook.exec_result = None
 
         if store_history:
             # Write output to the database. Does nothing unless
             # history output logging is enabled.
             self.history_manager.store_output(self.execution_count)
             # Each cell is a *single* input, regardless of how many lines it has
             self.execution_count += 1
 
         return result
 
     def transform_cell(self, raw_cell):
         """Transform an input cell before parsing it.
 
         Static transformations, implemented in IPython.core.inputtransformer2,
         deal with things like ``%magic`` and ``!system`` commands.
         These run on all input.
         Dynamic transformations, for things like unescaped magics and the exit
         autocall, depend on the state of the interpreter.
         These only apply to single line inputs.
 
         These string-based transformations are followed by AST transformations;
         see :meth:`transform_ast`.
         """
         # Static input transformations
         cell = self.input_transformer_manager.transform_cell(raw_cell)
 
         if len(cell.splitlines()) == 1:
             # Dynamic transformations - only applied for single line commands
             with self.builtin_trap:
                 # use prefilter_lines to handle trailing newlines
                 # restore trailing newline for ast.parse
                 cell = self.prefilter_manager.prefilter_lines(cell) + '\n'
 
         lines = cell.splitlines(keepends=True)
         for transform in self.input_transformers_post:
             lines = transform(lines)
         cell = ''.join(lines)
 
         return cell
 
     def transform_ast(self, node):
         """Apply the AST transformations from self.ast_transformers
 
         Parameters
         ----------
         node : ast.Node
             The root node to be transformed. Typically called with the ast.Module
             produced by parsing user input.
 
         Returns
         -------
         An ast.Node corresponding to the node it was called with. Note that it
         may also modify the passed object, so don't rely on references to the
         original AST.
         """
         for transformer in self.ast_transformers:
             try:
                 node = transformer.visit(node)
             except InputRejected:
                 # User-supplied AST transformers can reject an input by raising
                 # an InputRejected.  Short-circuit in this case so that we
                 # don't unregister the transform.
                 raise
             except Exception as e:
                 warn(
                     "AST transformer %r threw an error. It will be unregistered. %s"
                     % (transformer, e)
                 )
                 self.ast_transformers.remove(transformer)
 
         if self.ast_transformers:
             ast.fix_missing_locations(node)
         return node
 
     async def run_ast_nodes(
         self,
         nodelist: ListType[stmt],
         cell_name: str,
         interactivity="last_expr",
         compiler=compile,
         result=None,
     ):
         """Run a sequence of AST nodes. The execution mode depends on the
         interactivity parameter.
 
         Parameters
         ----------
         nodelist : list
           A sequence of AST nodes to run.
         cell_name : str
           Will be passed to the compiler as the filename of the cell. Typically
           the value returned by ip.compile.cache(cell).
         interactivity : str
           'all', 'last', 'last_expr' , 'last_expr_or_assign' or 'none',
           specifying which nodes should be run interactively (displaying output
           from expressions). 'last_expr' will run the last node interactively
           only if it is an expression (i.e. expressions in loops or other blocks
           are not displayed) 'last_expr_or_assign' will run the last expression
           or the last assignment. Other values for this parameter will raise a
           ValueError.
 
         compiler : callable
           A function with the same interface as the built-in compile(), to turn
           the AST nodes into code objects. Default is the built-in compile().
         result : ExecutionResult, optional
           An object to store exceptions that occur during execution.
 
         Returns
         -------
         True if an exception occurred while running code, False if it finished
         running.
         """
         if not nodelist:
             return
 
 
         if interactivity == 'last_expr_or_assign':
             if isinstance(nodelist[-1], _assign_nodes):
                 asg = nodelist[-1]
                 if isinstance(asg, ast.Assign) and len(asg.targets) == 1:
                     target = asg.targets[0]
                 elif isinstance(asg, _single_targets_nodes):
                     target = asg.target
                 else:
                     target = None
                 if isinstance(target, ast.Name):
                     nnode = ast.Expr(ast.Name(target.id, ast.Load()))
                     ast.fix_missing_locations(nnode)
                     nodelist.append(nnode)
             interactivity = 'last_expr'
 
         _async = False
         if interactivity == 'last_expr':
             if isinstance(nodelist[-1], ast.Expr):
                 interactivity = "last"
             else:
                 interactivity = "none"
 
         if interactivity == 'none':
             to_run_exec, to_run_interactive = nodelist, []
         elif interactivity == 'last':
             to_run_exec, to_run_interactive = nodelist[:-1], nodelist[-1:]
         elif interactivity == 'all':
             to_run_exec, to_run_interactive = [], nodelist
         else:
             raise ValueError("Interactivity was %r" % interactivity)
 
         try:
 
             def compare(code):
                 is_async = inspect.CO_COROUTINE & code.co_flags == inspect.CO_COROUTINE
                 return is_async
 
             # refactor that to just change the mod constructor.
             to_run = []
             for node in to_run_exec:
                 to_run.append((node, "exec"))
 
             for node in to_run_interactive:
                 to_run.append((node, "single"))
 
             for node, mode in to_run:
                 if mode == "exec":
                     mod = Module([node], [])
                 elif mode == "single":
                     mod = ast.Interactive([node])  # type: ignore
                 with compiler.extra_flags(
                     getattr(ast, "PyCF_ALLOW_TOP_LEVEL_AWAIT", 0x0)
                     if self.autoawait
                     else 0x0
                 ):
                     code = compiler(mod, cell_name, mode)
                     asy = compare(code)
                 if await self.run_code(code, result, async_=asy):
                     return True
 
             # Flush softspace
             if softspace(sys.stdout, 0):
                 print()
 
         except:
             # It's possible to have exceptions raised here, typically by
             # compilation of odd code (such as a naked 'return' outside a
             # function) that did parse but isn't valid. Typically the exception
             # is a SyntaxError, but it's safest just to catch anything and show
             # the user a traceback.
 
             # We do only one try/except outside the loop to minimize the impact
             # on runtime, and also because if any node in the node list is
             # broken, we should stop execution completely.
             if result:
                 result.error_before_exec = sys.exc_info()[1]
             self.showtraceback()
             return True
 
         return False
 
     async def run_code(self, code_obj, result=None, *, async_=False):
         """Execute a code object.
 
         When an exception occurs, self.showtraceback() is called to display a
         traceback.
 
         Parameters
         ----------
         code_obj : code object
           A compiled code object, to be executed
         result : ExecutionResult, optional
           An object to store exceptions that occur during execution.
         async_ :  Bool (Experimental)
           Attempt to run top-level asynchronous code in a default loop.
 
         Returns
         -------
         False : successful execution.
         True : an error occurred.
         """
         # special value to say that anything above is IPython and should be
         # hidden.
         __tracebackhide__ = "__ipython_bottom__"
         # Set our own excepthook in case the user code tries to call it
         # directly, so that the IPython crash handler doesn't get triggered
         old_excepthook, sys.excepthook = sys.excepthook, self.excepthook
 
         # we save the original sys.excepthook in the instance, in case config
         # code (such as magics) needs access to it.
         self.sys_excepthook = old_excepthook
         outflag = True  # happens in more places, so it's easier as default
         try:
             try:
                 if async_:
                     await eval(code_obj, self.user_global_ns, self.user_ns)
                 else:
                     exec(code_obj, self.user_global_ns, self.user_ns)
             finally:
                 # Reset our crash handler in place
                 sys.excepthook = old_excepthook
         except SystemExit as e:
             if result is not None:
                 result.error_in_exec = e
             self.showtraceback(exception_only=True)
             warn("To exit: use 'exit', 'quit', or Ctrl-D.", stacklevel=1)
         except bdb.BdbQuit:
             etype, value, tb = sys.exc_info()
             if result is not None:
                 result.error_in_exec = value
             # the BdbQuit stops here
         except self.custom_exceptions:
             etype, value, tb = sys.exc_info()
             if result is not None:
                 result.error_in_exec = value
             self.CustomTB(etype, value, tb)
         except:
             if result is not None:
                 result.error_in_exec = sys.exc_info()[1]
             self.showtraceback(running_compiled_code=True)
         else:
             outflag = False
         return outflag
 
     # For backwards compatibility
     runcode = run_code
 
     def check_complete(self, code: str) -> Tuple[str, str]:
         """Return whether a block of code is ready to execute, or should be continued
 
         Parameters
         ----------
         code : string
             Python input code, which can be multiline.
 
         Returns
         -------
         status : str
             One of 'complete', 'incomplete', or 'invalid' if source is not a
             prefix of valid code.
         indent : str
             When status is 'incomplete', this is some whitespace to insert on
             the next line of the prompt.
         """
         status, nspaces = self.input_transformer_manager.check_complete(code)
         return status, ' ' * (nspaces or 0)
 
     #-------------------------------------------------------------------------
     # Things related to GUI support and pylab
     #-------------------------------------------------------------------------
 
     active_eventloop: Optional[str] = None
 
     def enable_gui(self, gui=None):
         raise NotImplementedError('Implement enable_gui in a subclass')
 
     def enable_matplotlib(self, gui=None):
         """Enable interactive matplotlib and inline figure support.
 
         This takes the following steps:
 
         1. select the appropriate eventloop and matplotlib backend
         2. set up matplotlib for interactive use with that backend
         3. configure formatters for inline figure display
         4. enable the selected gui eventloop
 
         Parameters
         ----------
         gui : optional, string
             If given, dictates the choice of matplotlib GUI backend to use
             (should be one of IPython's supported backends, 'qt', 'osx', 'tk',
             'gtk', 'wx' or 'inline'), otherwise we use the default chosen by
             matplotlib (as dictated by the matplotlib build-time options plus the
             user's matplotlibrc configuration file).  Note that not all backends
             make sense in all contexts, for example a terminal ipython can't
             display figures inline.
         """
         from matplotlib_inline.backend_inline import configure_inline_support
 
         from IPython.core import pylabtools as pt
         gui, backend = pt.find_gui_and_backend(gui, self.pylab_gui_select)
 
         if gui != 'inline':
             # If we have our first gui selection, store it
             if self.pylab_gui_select is None:
                 self.pylab_gui_select = gui
             # Otherwise if they are different
             elif gui != self.pylab_gui_select:
                 print('Warning: Cannot change to a different GUI toolkit: %s.'
                         ' Using %s instead.' % (gui, self.pylab_gui_select))
                 gui, backend = pt.find_gui_and_backend(self.pylab_gui_select)
 
         pt.activate_matplotlib(backend)
         configure_inline_support(self, backend)
 
         # Now we must activate the gui pylab wants to use, and fix %run to take
         # plot updates into account
         self.enable_gui(gui)
         self.magics_manager.registry['ExecutionMagics'].default_runner = \
             pt.mpl_runner(self.safe_execfile)
 
         return gui, backend
 
     def enable_pylab(self, gui=None, import_all=True, welcome_message=False):
         """Activate pylab support at runtime.
 
         This turns on support for matplotlib, preloads into the interactive
         namespace all of numpy and pylab, and configures IPython to correctly
         interact with the GUI event loop.  The GUI backend to be used can be
         optionally selected with the optional ``gui`` argument.
 
         This method only adds preloading the namespace to InteractiveShell.enable_matplotlib.
 
         Parameters
         ----------
         gui : optional, string
             If given, dictates the choice of matplotlib GUI backend to use
             (should be one of IPython's supported backends, 'qt', 'osx', 'tk',
             'gtk', 'wx' or 'inline'), otherwise we use the default chosen by
             matplotlib (as dictated by the matplotlib build-time options plus the
             user's matplotlibrc configuration file).  Note that not all backends
             make sense in all contexts, for example a terminal ipython can't
             display figures inline.
         import_all : optional, bool, default: True
             Whether to do `from numpy import *` and `from pylab import *`
             in addition to module imports.
         welcome_message : deprecated
             This argument is ignored, no welcome message will be displayed.
         """
         from IPython.core.pylabtools import import_pylab
 
         gui, backend = self.enable_matplotlib(gui)
 
         # We want to prevent the loading of pylab to pollute the user's
         # namespace as shown by the %who* magics, so we execute the activation
         # code in an empty namespace, and we update *both* user_ns and
         # user_ns_hidden with this information.
         ns = {}
         import_pylab(ns, import_all)
         # warn about clobbered names
         ignored = {"__builtins__"}
         both = set(ns).intersection(self.user_ns).difference(ignored)
         clobbered = [ name for name in both if self.user_ns[name] is not ns[name] ]
         self.user_ns.update(ns)
         self.user_ns_hidden.update(ns)
         return gui, backend, clobbered
 
     #-------------------------------------------------------------------------
     # Utilities
     #-------------------------------------------------------------------------
 
     def var_expand(self, cmd, depth=0, formatter=DollarFormatter()):
         """Expand python variables in a string.
 
         The depth argument indicates how many frames above the caller should
         be walked to look for the local namespace where to expand variables.
 
         The global namespace for expansion is always the user's interactive
         namespace.
         """
         ns = self.user_ns.copy()
         try:
             frame = sys._getframe(depth+1)
         except ValueError:
             # This is thrown if there aren't that many frames on the stack,
             # e.g. if a script called run_line_magic() directly.
             pass
         else:
             ns.update(frame.f_locals)
 
         try:
             # We have to use .vformat() here, because 'self' is a valid and common
             # name, and expanding **ns for .format() would make it collide with
             # the 'self' argument of the method.
             cmd = formatter.vformat(cmd, args=[], kwargs=ns)
         except Exception:
             # if formatter couldn't format, just let it go untransformed
             pass
         return cmd
 
     def mktempfile(self, data=None, prefix='ipython_edit_'):
         """Make a new tempfile and return its filename.
 
         This makes a call to tempfile.mkstemp (created in a tempfile.mkdtemp),
         but it registers the created filename internally so ipython cleans it up
         at exit time.
 
         Optional inputs:
 
           - data(None): if data is given, it gets written out to the temp file
             immediately, and the file is closed again."""
 
         dir_path = Path(tempfile.mkdtemp(prefix=prefix))
         self.tempdirs.append(dir_path)
 
         handle, filename = tempfile.mkstemp(".py", prefix, dir=str(dir_path))
         os.close(handle)  # On Windows, there can only be one open handle on a file
 
         file_path = Path(filename)
         self.tempfiles.append(file_path)
 
         if data:
             file_path.write_text(data, encoding="utf-8")
         return filename
 
     def ask_yes_no(self, prompt, default=None, interrupt=None):
         if self.quiet:
             return True
         return ask_yes_no(prompt,default,interrupt)
 
     def show_usage(self):
         """Show a usage message"""
         page.page(IPython.core.usage.interactive_usage)
 
     def extract_input_lines(self, range_str, raw=False):
         """Return as a string a set of input history slices.
 
         Parameters
         ----------
         range_str : str
             The set of slices is given as a string, like "~5/6-~4/2 4:8 9",
             since this function is for use by magic functions which get their
             arguments as strings. The number before the / is the session
             number: ~n goes n back from the current session.
 
             If empty string is given, returns history of current session
             without the last input.
 
         raw : bool, optional
             By default, the processed input is used.  If this is true, the raw
             input history is used instead.
 
         Notes
         -----
         Slices can be described with two notations:
 
         * ``N:M`` -> standard python form, means including items N...(M-1).
         * ``N-M`` -> include items N..M (closed endpoint).
         """
         lines = self.history_manager.get_range_by_str(range_str, raw=raw)
         text = "\n".join(x for _, _, x in lines)
 
         # Skip the last line, as it's probably the magic that called this
         if not range_str:
             if "\n" not in text:
                 text = ""
             else:
                 text = text[: text.rfind("\n")]
 
         return text
 
     def find_user_code(self, target, raw=True, py_only=False, skip_encoding_cookie=True, search_ns=False):
         """Get a code string from history, file, url, or a string or macro.
 
         This is mainly used by magic functions.
 
         Parameters
         ----------
         target : str
             A string specifying code to retrieve. This will be tried respectively
             as: ranges of input history (see %history for syntax), url,
             corresponding .py file, filename, or an expression evaluating to a
             string or Macro in the user namespace.
 
             If empty string is given, returns complete history of current
             session, without the last line.
 
         raw : bool
             If true (default), retrieve raw history. Has no effect on the other
             retrieval mechanisms.
 
         py_only : bool (default False)
             Only try to fetch python code, do not try alternative methods to decode file
             if unicode fails.
 
         Returns
         -------
         A string of code.
         ValueError is raised if nothing is found, and TypeError if it evaluates
         to an object of another type. In each case, .args[0] is a printable
         message.
         """
         code = self.extract_input_lines(target, raw=raw)  # Grab history
         if code:
             return code
         try:
             if target.startswith(('http://', 'https://')):
                 return openpy.read_py_url(target, skip_encoding_cookie=skip_encoding_cookie)
         except UnicodeDecodeError as e:
             if not py_only :
                 # Deferred import
                 from urllib.request import urlopen
                 response = urlopen(target)
                 return response.read().decode('latin1')
             raise ValueError(("'%s' seem to be unreadable.") % target) from e
 
         potential_target = [target]
         try :
             potential_target.insert(0,get_py_filename(target))
         except IOError:
             pass
 
         for tgt in potential_target :
             if os.path.isfile(tgt):                        # Read file
                 try :
                     return openpy.read_py_file(tgt, skip_encoding_cookie=skip_encoding_cookie)
                 except UnicodeDecodeError as e:
                     if not py_only :
                         with io_open(tgt,'r', encoding='latin1') as f :
                             return f.read()
                     raise ValueError(("'%s' seem to be unreadable.") % target) from e
             elif os.path.isdir(os.path.expanduser(tgt)):
                 raise ValueError("'%s' is a directory, not a regular file." % target)
 
         if search_ns:
             # Inspect namespace to load object source
             object_info = self.object_inspect(target, detail_level=1)
             if object_info['found'] and object_info['source']:
                 return object_info['source']
 
         try:                                              # User namespace
             codeobj = eval(target, self.user_ns)
         except Exception as e:
             raise ValueError(("'%s' was not found in history, as a file, url, "
                                 "nor in the user namespace.") % target) from e
 
         if isinstance(codeobj, str):
             return codeobj
         elif isinstance(codeobj, Macro):
             return codeobj.value
 
         raise TypeError("%s is neither a string nor a macro." % target,
                         codeobj)
 
     def _atexit_once(self):
         """
         At exist operation that need to be called at most once.
         Second call to this function per instance will do nothing.
         """
 
         if not getattr(self, "_atexit_once_called", False):
             self._atexit_once_called = True
             # Clear all user namespaces to release all references cleanly.
             self.reset(new_session=False)
             # Close the history session (this stores the end time and line count)
             # this must be *before* the tempfile cleanup, in case of temporary
             # history db
             self.history_manager.end_session()
             self.history_manager = None
 
     #-------------------------------------------------------------------------
     # Things related to IPython exiting
     #-------------------------------------------------------------------------
     def atexit_operations(self):
         """This will be executed at the time of exit.
 
         Cleanup operations and saving of persistent data that is done
         unconditionally by IPython should be performed here.
 
         For things that may depend on startup flags or platform specifics (such
         as having readline or not), register a separate atexit function in the
         code that has the appropriate information, rather than trying to
         clutter
         """
         self._atexit_once()
 
         # Cleanup all tempfiles and folders left around
         for tfile in self.tempfiles:
             try:
                 tfile.unlink()
                 self.tempfiles.remove(tfile)
             except FileNotFoundError:
                 pass
         del self.tempfiles
         for tdir in self.tempdirs:
             try:
                 shutil.rmtree(tdir)
                 self.tempdirs.remove(tdir)
             except FileNotFoundError:
                 pass
         del self.tempdirs
 
         # Restore user's cursor
         if hasattr(self, "editing_mode") and self.editing_mode == "vi":
             sys.stdout.write("\x1b[0 q")
             sys.stdout.flush()
 
     def cleanup(self):
         self.restore_sys_module_state()
 
 
     # Overridden in terminal subclass to change prompts
     def switch_doctest_mode(self, mode):
         pass
 
 
 class InteractiveShellABC(metaclass=abc.ABCMeta):
     """An abstract base class for InteractiveShell."""
 
 InteractiveShellABC.register(InteractiveShell)

IPython/core/magics/ast_mod.py

@@ -1,320 +1,330 b''
 """
 This module contains utility function and classes to inject simple ast
 transformations based on code strings into IPython. While it is already possible
 with ast-transformers it is not easy to directly manipulate ast.
 
 
 IPython has pre-code and post-code hooks, but are ran from within the IPython
 machinery so may be inappropriate, for example for performance mesurement.
 
 This module give you tools to simplify this, and expose 2 classes:
 
 - `ReplaceCodeTransformer` which is a simple ast transformer based on code
   template,
 
 and for advance case:
 
 - `Mangler` which is a simple ast transformer that mangle names in the ast.
 
 
 Example, let's try to make a simple version of the ``timeit`` magic, that run a
 code snippet 10 times and print the average time taken.
 
 Basically we want to run :
 
 .. code-block:: python
 
     from time import perf_counter
     now = perf_counter()
     for i in range(10):
         __code__ # our code
     print(f"Time taken: {(perf_counter() - now)/10}")
     __ret__ # the result of the last statement
 
 Where ``__code__`` is the code snippet we want to run, and ``__ret__`` is the
 result, so that if we for example run `dataframe.head()` IPython still display
 the head of dataframe instead of nothing.
 
 Here is a complete example of a file `timit2.py` that define such a magic:
 
 .. code-block:: python
 
     from IPython.core.magic import (
         Magics,
         magics_class,
         line_cell_magic,
     )
     from IPython.core.magics.ast_mod import ReplaceCodeTransformer
     from textwrap import dedent
     import ast
 
     template = template = dedent('''
         from time import perf_counter
         now = perf_counter()
         for i in range(10):
             __code__
         print(f"Time taken: {(perf_counter() - now)/10}")
         __ret__
     '''
     )
 
 
     @magics_class
     class AstM(Magics):
         @line_cell_magic
         def t2(self, line, cell):
             transformer = ReplaceCodeTransformer.from_string(template)
             transformer.debug = True
             transformer.mangler.debug = True
             new_code = transformer.visit(ast.parse(cell))
             return exec(compile(new_code, "<ast>", "exec"))
 
 
     def load_ipython_extension(ip):
         ip.register_magics(AstM)
 
 
 
 .. code-block:: python
 
     In [1]: %load_ext timit2
 
     In [2]: %%t2
        ...: import time
        ...: time.sleep(0.05)
        ...:
        ...:
     Time taken: 0.05435649999999441
 
 
 If you wish to ran all the code enter in IPython in an ast transformer, you can
 do so as well:
 
 .. code-block:: python
 
     In [1]: from IPython.core.magics.ast_mod import ReplaceCodeTransformer
        ...:
        ...: template = '''
        ...: from time import perf_counter
        ...: now = perf_counter()
        ...: __code__
        ...: print(f"Code ran in {perf_counter()-now}")
        ...: __ret__'''
        ...:
        ...: get_ipython().ast_transformers.append(ReplaceCodeTransformer.from_string(template))
 
     In [2]: 1+1
     Code ran in 3.40410006174352e-05
     Out[2]: 2
 
 
 
 Hygiene and Mangling
 --------------------
 
 The ast transformer above is not hygienic, it may not work if the user code use
 the same variable names as the ones used in the template. For example.
 
 To help with this by default the `ReplaceCodeTransformer` will mangle all names
 staring with 3 underscores. This is a simple heuristic that should work in most
 case, but can be cumbersome in some case. We provide a `Mangler` class that can
 be overridden to change the mangling heuristic, or simply use the `mangle_all`
 utility function. It will _try_ to mangle all names (except `__ret__` and
 `__code__`), but this include builtins (``print``, ``range``, ``type``) and
 replace those by invalid identifiers py prepending ``mangle-``:
 ``mangle-print``, ``mangle-range``, ``mangle-type`` etc. This is not a problem
 as currently Python AST support invalid identifiers, but it may not be the case
 in the future.
 
 You can set `ReplaceCodeTransformer.debug=True` and
 `ReplaceCodeTransformer.mangler.debug=True` to see the code after mangling and
 transforming:
 
 .. code-block:: python
 
 
     In [1]: from IPython.core.magics.ast_mod import ReplaceCodeTransformer, mangle_all
        ...:
        ...: template = '''
        ...: from builtins import type, print
        ...: from time import perf_counter
        ...: now = perf_counter()
        ...: __code__
        ...: print(f"Code ran in {perf_counter()-now}")
        ...: __ret__'''
        ...:
        ...: transformer = ReplaceCodeTransformer.from_string(template, mangling_predicate=mangle_all)
 
 
     In [2]: transformer.debug = True
        ...: transformer.mangler.debug = True
        ...: get_ipython().ast_transformers.append(transformer)
 
     In [3]: 1+1
     Mangling Alias mangle-type
     Mangling Alias mangle-print
     Mangling Alias mangle-perf_counter
     Mangling now
     Mangling perf_counter
     Not mangling __code__
     Mangling print
     Mangling perf_counter
     Mangling now
     Not mangling __ret__
     ---- Transformed code ----
     from builtins import type as mangle-type, print as mangle-print
     from time import perf_counter as mangle-perf_counter
     mangle-now = mangle-perf_counter()
     ret-tmp = 1 + 1
     mangle-print(f'Code ran in {mangle-perf_counter() - mangle-now}')
     ret-tmp
     ---- ---------------- ----
     Code ran in 0.00013654199938173406
     Out[3]: 2
 
 
 """
 
 __skip_doctest__ = True
 
 
-from ast import NodeTransformer, Store, Load, Name, Expr, Assign, Module,  Import, ImportFrom
+from ast import (
+    NodeTransformer,
+    Store,
+    Load,
+    Name,
+    Expr,
+    Assign,
+    Module,
+    Import,
+    ImportFrom,
+)
 import ast
 import copy
 
 from typing import Dict, Optional, Union
 
 
 mangle_all = lambda name: False if name in ("__ret__", "__code__") else True
 
 
 class Mangler(NodeTransformer):
     """
     Mangle given names in and ast tree to make sure they do not conflict with
     user code.
     """
 
     enabled: bool = True
     debug: bool = False
 
     def log(self, *args, **kwargs):
         if self.debug:
             print(*args, **kwargs)
 
     def __init__(self, predicate=None):
         if predicate is None:
             predicate = lambda name: name.startswith("___")
         self.predicate = predicate
 
     def visit_Name(self, node):
         if self.predicate(node.id):
             self.log("Mangling", node.id)
             # Once in the ast we do not need
             # names to be valid identifiers.
             node.id = "mangle-" + node.id
         else:
             self.log("Not mangling", node.id)
         return node
 
     def visit_FunctionDef(self, node):
         if self.predicate(node.name):
             self.log("Mangling", node.name)
             node.name = "mangle-" + node.name
         else:
             self.log("Not mangling", node.name)
 
         for arg in node.args.args:
             if self.predicate(arg.arg):
                 self.log("Mangling function arg", arg.arg)
                 arg.arg = "mangle-" + arg.arg
             else:
                 self.log("Not mangling function arg", arg.arg)
         return self.generic_visit(node)
 
-    def visit_ImportFrom(self, node:ImportFrom):
+    def visit_ImportFrom(self, node: ImportFrom):
         return self._visit_Import_and_ImportFrom(node)
 
-    def visit_Import(self, node:Import):
+    def visit_Import(self, node: Import):
         return self._visit_Import_and_ImportFrom(node)
 
-    def _visit_Import_and_ImportFrom(self, node:Union[Import, ImportFrom]):
+    def _visit_Import_and_ImportFrom(self, node: Union[Import, ImportFrom]):
         for alias in node.names:
             asname = alias.name if alias.asname is None else alias.asname
             if self.predicate(asname):
                 new_name: str = "mangle-" + asname
                 self.log("Mangling Alias", new_name)
                 alias.asname = new_name
             else:
                 self.log("Not mangling Alias", alias.asname)
         return node
 
 
 class ReplaceCodeTransformer(NodeTransformer):
     enabled: bool = True
     debug: bool = False
     mangler: Mangler
 
     def __init__(
         self, template: Module, mapping: Optional[Dict] = None, mangling_predicate=None
     ):
         assert isinstance(mapping, (dict, type(None)))
         assert isinstance(mangling_predicate, (type(None), type(lambda: None)))
         assert isinstance(template, ast.Module)
         self.template = template
         self.mangler = Mangler(predicate=mangling_predicate)
         if mapping is None:
             mapping = {}
         self.mapping = mapping
 
     @classmethod
     def from_string(
         cls, template: str, mapping: Optional[Dict] = None, mangling_predicate=None
     ):
         return cls(
             ast.parse(template), mapping=mapping, mangling_predicate=mangling_predicate
         )
 
     def visit_Module(self, code):
         if not self.enabled:
             return code
         # if not isinstance(code, ast.Module):
         # recursively called...
         #    return generic_visit(self, code)
         last = code.body[-1]
         if isinstance(last, Expr):
             code.body.pop()
             code.body.append(Assign([Name("ret-tmp", ctx=Store())], value=last.value))
             ast.fix_missing_locations(code)
             ret = Expr(value=Name("ret-tmp", ctx=Load()))
             ret = ast.fix_missing_locations(ret)
             self.mapping["__ret__"] = ret
         else:
             self.mapping["__ret__"] = ast.parse("None").body[0]
         self.mapping["__code__"] = code.body
         tpl = ast.fix_missing_locations(self.template)
 
         tx = copy.deepcopy(tpl)
         tx = self.mangler.visit(tx)
         node = self.generic_visit(tx)
         node_2 = ast.fix_missing_locations(node)
         if self.debug:
             print("---- Transformed code ----")
             print(ast.unparse(node_2))
             print("---- ---------------- ----")
         return node_2
 
     # this does not work as the name might be in a list and one might want to extend the list.
     # def visit_Name(self, name):
     #     if name.id in self.mapping and name.id == "__ret__":
     #         print(name, "in mapping")
     #         if isinstance(name.ctx, ast.Store):
     #             return Name("tmp", ctx=Store())
     #         else:
     #             return copy.deepcopy(self.mapping[name.id])
     #     return name
 
     def visit_Expr(self, expr):
         if isinstance(expr.value, Name) and expr.value.id in self.mapping:
             if self.mapping[expr.value.id] is not None:
                 return copy.deepcopy(self.mapping[expr.value.id])
         return self.generic_visit(expr)

IPython/core/magics/script.py

@@ -1,371 +1,372 b''
 """Magic functions for running cells in various scripts."""
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import asyncio
 import asyncio.exceptions
 import atexit
 import errno
 import os
 import signal
 import sys
 import time
 from subprocess import CalledProcessError
 from threading import Thread
 
 from traitlets import Any, Dict, List, default
 
 from IPython.core import magic_arguments
 from IPython.core.async_helpers import _AsyncIOProxy
 from IPython.core.magic import Magics, cell_magic, line_magic, magics_class
 from IPython.utils.process import arg_split
 
 #-----------------------------------------------------------------------------
 # Magic implementation classes
 #-----------------------------------------------------------------------------
 
 def script_args(f):
     """single decorator for adding script args"""
     args = [
         magic_arguments.argument(
             '--out', type=str,
             help="""The variable in which to store stdout from the script.
             If the script is backgrounded, this will be the stdout *pipe*,
             instead of the stderr text itself and will not be auto closed.
             """
         ),
         magic_arguments.argument(
             '--err', type=str,
             help="""The variable in which to store stderr from the script.
             If the script is backgrounded, this will be the stderr *pipe*,
             instead of the stderr text itself and will not be autoclosed.
             """
         ),
         magic_arguments.argument(
             '--bg', action="store_true",
             help="""Whether to run the script in the background.
             If given, the only way to see the output of the command is
             with --out/err.
             """
         ),
         magic_arguments.argument(
             '--proc', type=str,
             help="""The variable in which to store Popen instance.
             This is used only when --bg option is given.
             """
         ),
         magic_arguments.argument(
             '--no-raise-error', action="store_false", dest='raise_error',
             help="""Whether you should raise an error message in addition to
             a stream on stderr if you get a nonzero exit code.
             """,
         ),
     ]
     for arg in args:
         f = arg(f)
     return f
 
 
 @magics_class
 class ScriptMagics(Magics):
     """Magics for talking to scripts
     
     This defines a base `%%script` cell magic for running a cell
     with a program in a subprocess, and registers a few top-level
     magics that call %%script with common interpreters.
     """
 
     event_loop = Any(
         help="""
         The event loop on which to run subprocesses
 
         Not the main event loop,
         because we want to be able to make blocking calls
         and have certain requirements we don't want to impose on the main loop.
         """
     )
 
-    script_magics = List(
+    script_magics: List = List(
         help="""Extra script cell magics to define
         
         This generates simple wrappers of `%%script foo` as `%%foo`.
         
         If you want to add script magics that aren't on your path,
         specify them in script_paths
         """,
     ).tag(config=True)
+
     @default('script_magics')
     def _script_magics_default(self):
         """default to a common list of programs"""
         
         defaults = [
             'sh',
             'bash',
             'perl',
             'ruby',
             'python',
             'python2',
             'python3',
             'pypy',
         ]
         if os.name == 'nt':
             defaults.extend([
                 'cmd',
             ])
         
         return defaults
     
     script_paths = Dict(
         help="""Dict mapping short 'ruby' names to full paths, such as '/opt/secret/bin/ruby'
         
         Only necessary for items in script_magics where the default path will not
         find the right interpreter.
         """
     ).tag(config=True)
     
     def __init__(self, shell=None):
         super(ScriptMagics, self).__init__(shell=shell)
         self._generate_script_magics()
         self.bg_processes = []
         atexit.register(self.kill_bg_processes)
 
     def __del__(self):
         self.kill_bg_processes()
     
     def _generate_script_magics(self):
         cell_magics = self.magics['cell']
         for name in self.script_magics:
             cell_magics[name] = self._make_script_magic(name)
     
     def _make_script_magic(self, name):
         """make a named magic, that calls %%script with a particular program"""
         # expand to explicit path if necessary:
         script = self.script_paths.get(name, name)
         
         @magic_arguments.magic_arguments()
         @script_args
         def named_script_magic(line, cell):
             # if line, add it as cl-flags
             if line:
                 line = "%s %s" % (script, line)
             else:
                 line = script
             return self.shebang(line, cell)
         
         # write a basic docstring:
         named_script_magic.__doc__ = \
         """%%{name} script magic
         
         Run cells with {script} in a subprocess.
         
         This is a shortcut for `%%script {script}`
         """.format(**locals())
         
         return named_script_magic
     
     @magic_arguments.magic_arguments()
     @script_args
     @cell_magic("script")
     def shebang(self, line, cell):
         """Run a cell via a shell command
 
         The `%%script` line is like the #! line of script,
         specifying a program (bash, perl, ruby, etc.) with which to run.
 
         The rest of the cell is run by that program.
 
         Examples
         --------
         ::
 
             In [1]: %%script bash
                ...: for i in 1 2 3; do
                ...:   echo $i
                ...: done
             1
             2
             3
         """
 
         # Create the event loop in which to run script magics
         # this operates on a background thread
         if self.event_loop is None:
             if sys.platform == "win32":
                 # don't override the current policy,
                 # just create an event loop
                 event_loop = asyncio.WindowsProactorEventLoopPolicy().new_event_loop()
             else:
                 event_loop = asyncio.new_event_loop()
             self.event_loop = event_loop
 
             # start the loop in a background thread
             asyncio_thread = Thread(target=event_loop.run_forever, daemon=True)
             asyncio_thread.start()
         else:
             event_loop = self.event_loop
 
         def in_thread(coro):
             """Call a coroutine on the asyncio thread"""
             return asyncio.run_coroutine_threadsafe(coro, event_loop).result()
 
         async def _readchunk(stream):
             try:
                 return await stream.readuntil(b"\n")
             except asyncio.exceptions.IncompleteReadError as e:
                 return e.partial
             except asyncio.exceptions.LimitOverrunError as e:
                 return await stream.read(e.consumed)
 
         async def _handle_stream(stream, stream_arg, file_object):
             while True:
                 chunk = (await _readchunk(stream)).decode("utf8", errors="replace")
                 if not chunk:
                     break
                 if stream_arg:
                     self.shell.user_ns[stream_arg] = chunk
                 else:
                     file_object.write(chunk)
                     file_object.flush()
 
         async def _stream_communicate(process, cell):
             process.stdin.write(cell)
             process.stdin.close()
             stdout_task = asyncio.create_task(
                 _handle_stream(process.stdout, args.out, sys.stdout)
             )
             stderr_task = asyncio.create_task(
                 _handle_stream(process.stderr, args.err, sys.stderr)
             )
             await asyncio.wait([stdout_task, stderr_task])
             await process.wait()
 
         argv = arg_split(line, posix=not sys.platform.startswith("win"))
         args, cmd = self.shebang.parser.parse_known_args(argv)
 
         try:
             p = in_thread(
                 asyncio.create_subprocess_exec(
                     *cmd,
                     stdout=asyncio.subprocess.PIPE,
                     stderr=asyncio.subprocess.PIPE,
                     stdin=asyncio.subprocess.PIPE,
                 )
             )
         except OSError as e:
             if e.errno == errno.ENOENT:
                 print("Couldn't find program: %r" % cmd[0])
                 return
             else:
                 raise
 
         if not cell.endswith('\n'):
             cell += '\n'
         cell = cell.encode('utf8', 'replace')
         if args.bg:
             self.bg_processes.append(p)
             self._gc_bg_processes()
             to_close = []
             if args.out:
                 self.shell.user_ns[args.out] = _AsyncIOProxy(p.stdout, event_loop)
             else:
                 to_close.append(p.stdout)
             if args.err:
                 self.shell.user_ns[args.err] = _AsyncIOProxy(p.stderr, event_loop)
             else:
                 to_close.append(p.stderr)
             event_loop.call_soon_threadsafe(
                 lambda: asyncio.Task(self._run_script(p, cell, to_close))
             )
             if args.proc:
                 proc_proxy = _AsyncIOProxy(p, event_loop)
                 proc_proxy.stdout = _AsyncIOProxy(p.stdout, event_loop)
                 proc_proxy.stderr = _AsyncIOProxy(p.stderr, event_loop)
                 self.shell.user_ns[args.proc] = proc_proxy
             return
 
         try:
             in_thread(_stream_communicate(p, cell))
         except KeyboardInterrupt:
             try:
                 p.send_signal(signal.SIGINT)
                 in_thread(asyncio.wait_for(p.wait(), timeout=0.1))
                 if p.returncode is not None:
                     print("Process is interrupted.")
                     return
                 p.terminate()
                 in_thread(asyncio.wait_for(p.wait(), timeout=0.1))
                 if p.returncode is not None:
                     print("Process is terminated.")
                     return
                 p.kill()
                 print("Process is killed.")
             except OSError:
                 pass
             except Exception as e:
                 print("Error while terminating subprocess (pid=%i): %s" % (p.pid, e))
             return
 
         if args.raise_error and p.returncode != 0:
             # If we get here and p.returncode is still None, we must have
             # killed it but not yet seen its return code. We don't wait for it,
             # in case it's stuck in uninterruptible sleep. -9 = SIGKILL
             rc = p.returncode or -9
             raise CalledProcessError(rc, cell)
 
     shebang.__skip_doctest__ = os.name != "posix"
 
     async def _run_script(self, p, cell, to_close):
         """callback for running the script in the background"""
 
         p.stdin.write(cell)
         await p.stdin.drain()
         p.stdin.close()
         await p.stdin.wait_closed()
         await p.wait()
         # asyncio read pipes have no close
         # but we should drain the data anyway
         for s in to_close:
             await s.read()
         self._gc_bg_processes()
 
     @line_magic("killbgscripts")
     def killbgscripts(self, _nouse_=''):
         """Kill all BG processes started by %%script and its family."""
         self.kill_bg_processes()
         print("All background processes were killed.")
 
     def kill_bg_processes(self):
         """Kill all BG processes which are still running."""
         if not self.bg_processes:
             return
         for p in self.bg_processes:
             if p.returncode is None:
                 try:
                     p.send_signal(signal.SIGINT)
                 except:
                     pass
         time.sleep(0.1)
         self._gc_bg_processes()
         if not self.bg_processes:
             return
         for p in self.bg_processes:
             if p.returncode is None:
                 try:
                     p.terminate()
                 except:
                     pass
         time.sleep(0.1)
         self._gc_bg_processes()
         if not self.bg_processes:
             return
         for p in self.bg_processes:
             if p.returncode is None:
                 try:
                     p.kill()
                 except:
                     pass
         self._gc_bg_processes()
 
     def _gc_bg_processes(self):
         self.bg_processes = [p for p in self.bg_processes if p.returncode is None]

IPython/core/prefilter.py

@@ -1,700 +1,703 b''
 # encoding: utf-8
 """
 Prefiltering components.
 
 Prefilters transform user input before it is exec'd by Python.  These
 transforms are used to implement additional syntax such as !ls and %magic.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 from keyword import iskeyword
 import re
 
 from .autocall import IPyAutocall
 from traitlets.config.configurable import Configurable
 from .inputtransformer2 import (
     ESC_MAGIC,
     ESC_QUOTE,
     ESC_QUOTE2,
     ESC_PAREN,
 )
 from .macro import Macro
 from .splitinput import LineInfo
 
 from traitlets import (
     List, Integer, Unicode, Bool, Instance, CRegExp
 )
 
 #-----------------------------------------------------------------------------
 # Global utilities, errors and constants
 #-----------------------------------------------------------------------------
 
 
 class PrefilterError(Exception):
     pass
 
 
 # RegExp to identify potential function names
 re_fun_name = re.compile(r'[^\W\d]([\w.]*) *$')
 
 # RegExp to exclude strings with this start from autocalling.  In
 # particular, all binary operators should be excluded, so that if foo is
 # callable, foo OP bar doesn't become foo(OP bar), which is invalid.  The
 # characters '!=()' don't need to be checked for, as the checkPythonChars
 # routine explicitly does so, to catch direct calls and rebindings of
 # existing names.
 
 # Warning: the '-' HAS TO BE AT THE END of the first group, otherwise
 # it affects the rest of the group in square brackets.
 re_exclude_auto = re.compile(r'^[,&^\|\*/\+-]'
                              r'|^is |^not |^in |^and |^or ')
 
 # try to catch also methods for stuff in lists/tuples/dicts: off
 # (experimental). For this to work, the line_split regexp would need
 # to be modified so it wouldn't break things at '['. That line is
 # nasty enough that I shouldn't change it until I can test it _well_.
 #self.re_fun_name = re.compile (r'[a-zA-Z_]([a-zA-Z0-9_.\[\]]*) ?$')
 
 
 # Handler Check Utilities
 def is_shadowed(identifier, ip):
     """Is the given identifier defined in one of the namespaces which shadow
     the alias and magic namespaces?  Note that an identifier is different
     than ifun, because it can not contain a '.' character."""
     # This is much safer than calling ofind, which can change state
     return (identifier in ip.user_ns \
             or identifier in ip.user_global_ns \
             or identifier in ip.ns_table['builtin']\
             or iskeyword(identifier))
 
 
 #-----------------------------------------------------------------------------
 # Main Prefilter manager
 #-----------------------------------------------------------------------------
 
 
 class PrefilterManager(Configurable):
     """Main prefilter component.
 
     The IPython prefilter is run on all user input before it is run.  The
     prefilter consumes lines of input and produces transformed lines of
     input.
 
     The implementation consists of two phases:
 
     1. Transformers
     2. Checkers and handlers
 
     Over time, we plan on deprecating the checkers and handlers and doing
     everything in the transformers.
 
     The transformers are instances of :class:`PrefilterTransformer` and have
     a single method :meth:`transform` that takes a line and returns a
     transformed line.  The transformation can be accomplished using any
     tool, but our current ones use regular expressions for speed.
 
     After all the transformers have been run, the line is fed to the checkers,
     which are instances of :class:`PrefilterChecker`.  The line is passed to
     the :meth:`check` method, which either returns `None` or a
     :class:`PrefilterHandler` instance.  If `None` is returned, the other
     checkers are tried.  If an :class:`PrefilterHandler` instance is returned,
     the line is passed to the :meth:`handle` method of the returned
     handler and no further checkers are tried.
 
     Both transformers and checkers have a `priority` attribute, that determines
     the order in which they are called.  Smaller priorities are tried first.
 
     Both transformers and checkers also have `enabled` attribute, which is
     a boolean that determines if the instance is used.
 
     Users or developers can change the priority or enabled attribute of
     transformers or checkers, but they must call the :meth:`sort_checkers`
     or :meth:`sort_transformers` method after changing the priority.
     """
 
     multi_line_specials = Bool(True).tag(config=True)
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
 
     def __init__(self, shell=None, **kwargs):
         super(PrefilterManager, self).__init__(shell=shell, **kwargs)
         self.shell = shell
         self._transformers = []
         self.init_handlers()
         self.init_checkers()
 
     #-------------------------------------------------------------------------
     # API for managing transformers
     #-------------------------------------------------------------------------
 
     def sort_transformers(self):
         """Sort the transformers by priority.
 
         This must be called after the priority of a transformer is changed.
         The :meth:`register_transformer` method calls this automatically.
         """
         self._transformers.sort(key=lambda x: x.priority)
 
     @property
     def transformers(self):
         """Return a list of checkers, sorted by priority."""
         return self._transformers
 
     def register_transformer(self, transformer):
         """Register a transformer instance."""
         if transformer not in self._transformers:
             self._transformers.append(transformer)
             self.sort_transformers()
 
     def unregister_transformer(self, transformer):
         """Unregister a transformer instance."""
         if transformer in self._transformers:
             self._transformers.remove(transformer)
 
     #-------------------------------------------------------------------------
     # API for managing checkers
     #-------------------------------------------------------------------------
 
     def init_checkers(self):
         """Create the default checkers."""
         self._checkers = []
         for checker in _default_checkers:
             checker(
                 shell=self.shell, prefilter_manager=self, parent=self
             )
 
     def sort_checkers(self):
         """Sort the checkers by priority.
 
         This must be called after the priority of a checker is changed.
         The :meth:`register_checker` method calls this automatically.
         """
         self._checkers.sort(key=lambda x: x.priority)
 
     @property
     def checkers(self):
         """Return a list of checkers, sorted by priority."""
         return self._checkers
 
     def register_checker(self, checker):
         """Register a checker instance."""
         if checker not in self._checkers:
             self._checkers.append(checker)
             self.sort_checkers()
 
     def unregister_checker(self, checker):
         """Unregister a checker instance."""
         if checker in self._checkers:
             self._checkers.remove(checker)
 
     #-------------------------------------------------------------------------
     # API for managing handlers
     #-------------------------------------------------------------------------
 
     def init_handlers(self):
         """Create the default handlers."""
         self._handlers = {}
         self._esc_handlers = {}
         for handler in _default_handlers:
             handler(
                 shell=self.shell, prefilter_manager=self, parent=self
             )
 
     @property
     def handlers(self):
         """Return a dict of all the handlers."""
         return self._handlers
 
     def register_handler(self, name, handler, esc_strings):
         """Register a handler instance by name with esc_strings."""
         self._handlers[name] = handler
         for esc_str in esc_strings:
             self._esc_handlers[esc_str] = handler
 
     def unregister_handler(self, name, handler, esc_strings):
         """Unregister a handler instance by name with esc_strings."""
         try:
             del self._handlers[name]
         except KeyError:
             pass
         for esc_str in esc_strings:
             h = self._esc_handlers.get(esc_str)
             if h is handler:
                 del self._esc_handlers[esc_str]
 
     def get_handler_by_name(self, name):
         """Get a handler by its name."""
         return self._handlers.get(name)
 
     def get_handler_by_esc(self, esc_str):
         """Get a handler by its escape string."""
         return self._esc_handlers.get(esc_str)
 
     #-------------------------------------------------------------------------
     # Main prefiltering API
     #-------------------------------------------------------------------------
 
     def prefilter_line_info(self, line_info):
         """Prefilter a line that has been converted to a LineInfo object.
 
         This implements the checker/handler part of the prefilter pipe.
         """
         # print "prefilter_line_info: ", line_info
         handler = self.find_handler(line_info)
         return handler.handle(line_info)
 
     def find_handler(self, line_info):
         """Find a handler for the line_info by trying checkers."""
         for checker in self.checkers:
             if checker.enabled:
                 handler = checker.check(line_info)
                 if handler:
                     return handler
         return self.get_handler_by_name('normal')
 
     def transform_line(self, line, continue_prompt):
         """Calls the enabled transformers in order of increasing priority."""
         for transformer in self.transformers:
             if transformer.enabled:
                 line = transformer.transform(line, continue_prompt)
         return line
 
     def prefilter_line(self, line, continue_prompt=False):
         """Prefilter a single input line as text.
 
         This method prefilters a single line of text by calling the
         transformers and then the checkers/handlers.
         """
 
         # print "prefilter_line: ", line, continue_prompt
         # All handlers *must* return a value, even if it's blank ('').
 
         # save the line away in case we crash, so the post-mortem handler can
         # record it
         self.shell._last_input_line = line
 
         if not line:
             # Return immediately on purely empty lines, so that if the user
             # previously typed some whitespace that started a continuation
             # prompt, he can break out of that loop with just an empty line.
             # This is how the default python prompt works.
             return ''
 
         # At this point, we invoke our transformers.
         if not continue_prompt or (continue_prompt and self.multi_line_specials):
             line = self.transform_line(line, continue_prompt)
 
         # Now we compute line_info for the checkers and handlers
         line_info = LineInfo(line, continue_prompt)
 
         # the input history needs to track even empty lines
         stripped = line.strip()
 
         normal_handler = self.get_handler_by_name('normal')
         if not stripped:
             return normal_handler.handle(line_info)
 
         # special handlers are only allowed for single line statements
         if continue_prompt and not self.multi_line_specials:
             return normal_handler.handle(line_info)
 
         prefiltered = self.prefilter_line_info(line_info)
         # print "prefiltered line: %r" % prefiltered
         return prefiltered
 
     def prefilter_lines(self, lines, continue_prompt=False):
         """Prefilter multiple input lines of text.
 
         This is the main entry point for prefiltering multiple lines of
         input.  This simply calls :meth:`prefilter_line` for each line of
         input.
 
         This covers cases where there are multiple lines in the user entry,
         which is the case when the user goes back to a multiline history
         entry and presses enter.
         """
         llines = lines.rstrip('\n').split('\n')
         # We can get multiple lines in one shot, where multiline input 'blends'
         # into one line, in cases like recalling from the readline history
         # buffer.  We need to make sure that in such cases, we correctly
         # communicate downstream which line is first and which are continuation
         # ones.
         if len(llines) > 1:
             out = '\n'.join([self.prefilter_line(line, lnum>0)
                              for lnum, line in enumerate(llines) ])
         else:
             out = self.prefilter_line(llines[0], continue_prompt)
 
         return out
 
 #-----------------------------------------------------------------------------
 # Prefilter transformers
 #-----------------------------------------------------------------------------
 
 
 class PrefilterTransformer(Configurable):
     """Transform a line of user input."""
 
     priority = Integer(100).tag(config=True)
     # Transformers don't currently use shell or prefilter_manager, but as we
     # move away from checkers and handlers, they will need them.
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
     prefilter_manager = Instance('IPython.core.prefilter.PrefilterManager', allow_none=True)
     enabled = Bool(True).tag(config=True)
 
     def __init__(self, shell=None, prefilter_manager=None, **kwargs):
         super(PrefilterTransformer, self).__init__(
             shell=shell, prefilter_manager=prefilter_manager, **kwargs
         )
         self.prefilter_manager.register_transformer(self)
 
     def transform(self, line, continue_prompt):
         """Transform a line, returning the new one."""
         return None
 
     def __repr__(self):
         return "<%s(priority=%r, enabled=%r)>" % (
             self.__class__.__name__, self.priority, self.enabled)
 
 
 #-----------------------------------------------------------------------------
 # Prefilter checkers
 #-----------------------------------------------------------------------------
 
 
 class PrefilterChecker(Configurable):
     """Inspect an input line and return a handler for that line."""
 
     priority = Integer(100).tag(config=True)
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
     prefilter_manager = Instance('IPython.core.prefilter.PrefilterManager', allow_none=True)
     enabled = Bool(True).tag(config=True)
 
     def __init__(self, shell=None, prefilter_manager=None, **kwargs):
         super(PrefilterChecker, self).__init__(
             shell=shell, prefilter_manager=prefilter_manager, **kwargs
         )
         self.prefilter_manager.register_checker(self)
 
     def check(self, line_info):
         """Inspect line_info and return a handler instance or None."""
         return None
 
     def __repr__(self):
         return "<%s(priority=%r, enabled=%r)>" % (
             self.__class__.__name__, self.priority, self.enabled)
 
 
 class EmacsChecker(PrefilterChecker):
 
     priority = Integer(100).tag(config=True)
     enabled = Bool(False).tag(config=True)
 
     def check(self, line_info):
         "Emacs ipython-mode tags certain input lines."
         if line_info.line.endswith('# PYTHON-MODE'):
             return self.prefilter_manager.get_handler_by_name('emacs')
         else:
             return None
 
 
 class MacroChecker(PrefilterChecker):
 
     priority = Integer(250).tag(config=True)
 
     def check(self, line_info):
         obj = self.shell.user_ns.get(line_info.ifun)
         if isinstance(obj, Macro):
             return self.prefilter_manager.get_handler_by_name('macro')
         else:
             return None
 
 
 class IPyAutocallChecker(PrefilterChecker):
 
     priority = Integer(300).tag(config=True)
 
     def check(self, line_info):
         "Instances of IPyAutocall in user_ns get autocalled immediately"
         obj = self.shell.user_ns.get(line_info.ifun, None)
         if isinstance(obj, IPyAutocall):
             obj.set_ip(self.shell)
             return self.prefilter_manager.get_handler_by_name('auto')
         else:
             return None
 
 
 class AssignmentChecker(PrefilterChecker):
 
     priority = Integer(600).tag(config=True)
 
     def check(self, line_info):
         """Check to see if user is assigning to a var for the first time, in
         which case we want to avoid any sort of automagic / autocall games.
 
         This allows users to assign to either alias or magic names true python
         variables (the magic/alias systems always take second seat to true
         python code).  E.g. ls='hi', or ls,that=1,2"""
         if line_info.the_rest:
             if line_info.the_rest[0] in '=,':
                 return self.prefilter_manager.get_handler_by_name('normal')
         else:
             return None
 
 
 class AutoMagicChecker(PrefilterChecker):
 
     priority = Integer(700).tag(config=True)
 
     def check(self, line_info):
         """If the ifun is magic, and automagic is on, run it.  Note: normal,
         non-auto magic would already have been triggered via '%' in
         check_esc_chars. This just checks for automagic.  Also, before
         triggering the magic handler, make sure that there is nothing in the
         user namespace which could shadow it."""
         if not self.shell.automagic or not self.shell.find_magic(line_info.ifun):
             return None
 
         # We have a likely magic method.  Make sure we should actually call it.
         if line_info.continue_prompt and not self.prefilter_manager.multi_line_specials:
             return None
 
         head = line_info.ifun.split('.',1)[0]
         if is_shadowed(head, self.shell):
             return None
 
         return self.prefilter_manager.get_handler_by_name('magic')
 
 
 class PythonOpsChecker(PrefilterChecker):
 
     priority = Integer(900).tag(config=True)
 
     def check(self, line_info):
         """If the 'rest' of the line begins with a function call or pretty much
         any python operator, we should simply execute the line (regardless of
         whether or not there's a possible autocall expansion).  This avoids
         spurious (and very confusing) geattr() accesses."""
         if line_info.the_rest and line_info.the_rest[0] in '!=()<>,+*/%^&|':
             return self.prefilter_manager.get_handler_by_name('normal')
         else:
             return None
 
 
 class AutocallChecker(PrefilterChecker):
 
     priority = Integer(1000).tag(config=True)
 
     function_name_regexp = CRegExp(re_fun_name,
         help="RegExp to identify potential function names."
         ).tag(config=True)
     exclude_regexp = CRegExp(re_exclude_auto,
         help="RegExp to exclude strings with this start from autocalling."
         ).tag(config=True)
 
     def check(self, line_info):
         "Check if the initial word/function is callable and autocall is on."
         if not self.shell.autocall:
             return None
 
         oinfo = line_info.ofind(self.shell) # This can mutate state via getattr
         if not oinfo.found:
             return None
 
         ignored_funs = ['b', 'f', 'r', 'u', 'br', 'rb', 'fr', 'rf']
         ifun = line_info.ifun
         line = line_info.line
         if ifun.lower() in ignored_funs and (line.startswith(ifun + "'") or line.startswith(ifun + '"')):
             return None
 
         if (
             callable(oinfo.obj)
             and (not self.exclude_regexp.match(line_info.the_rest))
             and self.function_name_regexp.match(line_info.ifun)
         ):
             return self.prefilter_manager.get_handler_by_name("auto")
         else:
             return None
 
 
 #-----------------------------------------------------------------------------
 # Prefilter handlers
 #-----------------------------------------------------------------------------
 
 
 class PrefilterHandler(Configurable):
-
-    handler_name = Unicode('normal')
-    esc_strings = List([])
-    shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
-    prefilter_manager = Instance('IPython.core.prefilter.PrefilterManager', allow_none=True)
+    handler_name = Unicode("normal")
+    esc_strings: List = List([])
+    shell = Instance(
+        "IPython.core.interactiveshell.InteractiveShellABC", allow_none=True
+    )
+    prefilter_manager = Instance(
+        "IPython.core.prefilter.PrefilterManager", allow_none=True
+    )
 
     def __init__(self, shell=None, prefilter_manager=None, **kwargs):
         super(PrefilterHandler, self).__init__(
             shell=shell, prefilter_manager=prefilter_manager, **kwargs
         )
         self.prefilter_manager.register_handler(
             self.handler_name,
             self,
             self.esc_strings
         )
 
     def handle(self, line_info):
         # print "normal: ", line_info
         """Handle normal input lines. Use as a template for handlers."""
 
         # With autoindent on, we need some way to exit the input loop, and I
         # don't want to force the user to have to backspace all the way to
         # clear the line.  The rule will be in this case, that either two
         # lines of pure whitespace in a row, or a line of pure whitespace but
         # of a size different to the indent level, will exit the input loop.
         line = line_info.line
         continue_prompt = line_info.continue_prompt
 
         if (continue_prompt and
             self.shell.autoindent and
             line.isspace() and
             0 < abs(len(line) - self.shell.indent_current_nsp) <= 2):
             line = ''
 
         return line
 
     def __str__(self):
         return "<%s(name=%s)>" % (self.__class__.__name__, self.handler_name)
 
 
 class MacroHandler(PrefilterHandler):
     handler_name = Unicode("macro")
 
     def handle(self, line_info):
         obj = self.shell.user_ns.get(line_info.ifun)
         pre_space = line_info.pre_whitespace
         line_sep = "\n" + pre_space
         return pre_space + line_sep.join(obj.value.splitlines())
 
 
 class MagicHandler(PrefilterHandler):
 
     handler_name = Unicode('magic')
     esc_strings = List([ESC_MAGIC])
 
     def handle(self, line_info):
         """Execute magic functions."""
         ifun    = line_info.ifun
         the_rest = line_info.the_rest
         #Prepare arguments for get_ipython().run_line_magic(magic_name, magic_args)
         t_arg_s = ifun + " " + the_rest
         t_magic_name, _, t_magic_arg_s = t_arg_s.partition(' ')
         t_magic_name = t_magic_name.lstrip(ESC_MAGIC)
         cmd = '%sget_ipython().run_line_magic(%r, %r)' % (line_info.pre_whitespace, t_magic_name, t_magic_arg_s)
         return cmd
 
 
 class AutoHandler(PrefilterHandler):
 
     handler_name = Unicode('auto')
     esc_strings = List([ESC_PAREN, ESC_QUOTE, ESC_QUOTE2])
 
     def handle(self, line_info):
         """Handle lines which can be auto-executed, quoting if requested."""
         line    = line_info.line
         ifun    = line_info.ifun
         the_rest = line_info.the_rest
         esc     = line_info.esc
         continue_prompt = line_info.continue_prompt
         obj = line_info.ofind(self.shell).obj
 
         # This should only be active for single-line input!
         if continue_prompt:
             return line
 
         force_auto = isinstance(obj, IPyAutocall)
 
         # User objects sometimes raise exceptions on attribute access other
         # than AttributeError (we've seen it in the past), so it's safest to be
         # ultra-conservative here and catch all.
         try:
             auto_rewrite = obj.rewrite
         except Exception:
             auto_rewrite = True
 
         if esc == ESC_QUOTE:
             # Auto-quote splitting on whitespace
             newcmd = '%s("%s")' % (ifun,'", "'.join(the_rest.split()) )
         elif esc == ESC_QUOTE2:
             # Auto-quote whole string
             newcmd = '%s("%s")' % (ifun,the_rest)
         elif esc == ESC_PAREN:
             newcmd = '%s(%s)' % (ifun,",".join(the_rest.split()))
         else:
             # Auto-paren.
             if force_auto:
                 # Don't rewrite if it is already a call.
                 do_rewrite = not the_rest.startswith('(')
             else:
                 if not the_rest:
                     # We only apply it to argument-less calls if the autocall
                     # parameter is set to 2.
                     do_rewrite = (self.shell.autocall >= 2)
                 elif the_rest.startswith('[') and hasattr(obj, '__getitem__'):
                     # Don't autocall in this case: item access for an object
                     # which is BOTH callable and implements __getitem__.
                     do_rewrite = False
                 else:
                     do_rewrite = True
 
             # Figure out the rewritten command
             if do_rewrite:
                 if the_rest.endswith(';'):
                     newcmd = '%s(%s);' % (ifun.rstrip(),the_rest[:-1])
                 else:
                     newcmd = '%s(%s)' % (ifun.rstrip(), the_rest)
             else:
                 normal_handler = self.prefilter_manager.get_handler_by_name('normal')
                 return normal_handler.handle(line_info)
 
         # Display the rewritten call
         if auto_rewrite:
             self.shell.auto_rewrite_input(newcmd)
 
         return newcmd
 
 
 class EmacsHandler(PrefilterHandler):
 
     handler_name = Unicode('emacs')
     esc_strings = List([])
 
     def handle(self, line_info):
         """Handle input lines marked by python-mode."""
 
         # Currently, nothing is done.  Later more functionality can be added
         # here if needed.
 
         # The input cache shouldn't be updated
         return line_info.line
 
 
 #-----------------------------------------------------------------------------
 # Defaults
 #-----------------------------------------------------------------------------
 
 
 _default_checkers = [
     EmacsChecker,
     MacroChecker,
     IPyAutocallChecker,
     AssignmentChecker,
     AutoMagicChecker,
     PythonOpsChecker,
     AutocallChecker
 ]
 
 _default_handlers = [
     PrefilterHandler,
     MacroHandler,
     MagicHandler,
     AutoHandler,
     EmacsHandler
 ]