Update what's new and limit number of subclasses.

It was always my plan to limit, but I forget and rememebered while
writing the notes.

IPython/core/oinspect.py

@@ -1,1059 +1,1062 b''
 # -*- coding: utf-8 -*-
 """Tools for inspecting Python objects.
 
 Uses syntax highlighting for presenting the various information elements.
 
 Similar in spirit to the inspect module, but all calls take a name argument to
 reference the name under which an object is being read.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 __all__ = ['Inspector','InspectColors']
 
 # stdlib modules
 import ast
 import inspect
 from inspect import signature
 import linecache
 import warnings
 import os
 from textwrap import dedent
 import types
 import io as stdlib_io
 from itertools import zip_longest
 
 # IPython's own
 from IPython.core import page
 from IPython.lib.pretty import pretty
 from IPython.testing.skipdoctest import skip_doctest
 from IPython.utils import PyColorize
 from IPython.utils import openpy
 from IPython.utils import py3compat
 from IPython.utils.dir2 import safe_hasattr
 from IPython.utils.path import compress_user
 from IPython.utils.text import indent
 from IPython.utils.wildcard import list_namespace
 from IPython.utils.coloransi import TermColors, ColorScheme, ColorSchemeTable
 from IPython.utils.py3compat import cast_unicode
 from IPython.utils.colorable import Colorable
 from IPython.utils.decorators import undoc
 
 from pygments import highlight
 from pygments.lexers import PythonLexer
 from pygments.formatters import HtmlFormatter
 
 def pylight(code):
     return highlight(code, PythonLexer(), HtmlFormatter(noclasses=True))
 
 # builtin docstrings to ignore
 _func_call_docstring = types.FunctionType.__call__.__doc__
 _object_init_docstring = object.__init__.__doc__
 _builtin_type_docstrings = {
     inspect.getdoc(t) for t in (types.ModuleType, types.MethodType,
                                 types.FunctionType, property)
 }
 
 _builtin_func_type = type(all)
 _builtin_meth_type = type(str.upper)  # Bound methods have the same type as builtin functions
 #****************************************************************************
 # Builtin color schemes
 
 Colors = TermColors  # just a shorthand
 
 InspectColors = PyColorize.ANSICodeColors
 
 #****************************************************************************
 # Auxiliary functions and objects
 
 # See the messaging spec for the definition of all these fields.  This list
 # effectively defines the order of display
 info_fields = ['type_name', 'base_class', 'string_form', 'namespace',
                'length', 'file', 'definition', 'docstring', 'source',
                'init_definition', 'class_docstring', 'init_docstring',
                'call_def', 'call_docstring',
                # These won't be printed but will be used to determine how to
                # format the object
                'ismagic', 'isalias', 'isclass', 'argspec', 'found', 'name'
                ]
 
 
 def object_info(**kw):
     """Make an object info dict with all fields present."""
     infodict = dict(zip_longest(info_fields, [None]))
     infodict.update(kw)
     return infodict
 
 
 def get_encoding(obj):
     """Get encoding for python source file defining obj
 
     Returns None if obj is not defined in a sourcefile.
     """
     ofile = find_file(obj)
     # run contents of file through pager starting at line where the object
     # is defined, as long as the file isn't binary and is actually on the
     # filesystem.
     if ofile is None:
         return None
     elif ofile.endswith(('.so', '.dll', '.pyd')):
         return None
     elif not os.path.isfile(ofile):
         return None
     else:
         # Print only text files, not extension binaries.  Note that
         # getsourcelines returns lineno with 1-offset and page() uses
         # 0-offset, so we must adjust.
         with stdlib_io.open(ofile, 'rb') as buffer:   # Tweaked to use io.open for Python 2
             encoding, lines = openpy.detect_encoding(buffer.readline)
         return encoding
 
 def getdoc(obj):
     """Stable wrapper around inspect.getdoc.
 
     This can't crash because of attribute problems.
 
     It also attempts to call a getdoc() method on the given object.  This
     allows objects which provide their docstrings via non-standard mechanisms
     (like Pyro proxies) to still be inspected by ipython's ? system.
     """
     # Allow objects to offer customized documentation via a getdoc method:
     try:
         ds = obj.getdoc()
     except Exception:
         pass
     else:
         if isinstance(ds, str):
             return inspect.cleandoc(ds)
     docstr = inspect.getdoc(obj)
     encoding = get_encoding(obj)
     return py3compat.cast_unicode(docstr, encoding=encoding)
 
 
 def getsource(obj, oname=''):
     """Wrapper around inspect.getsource.
 
     This can be modified by other projects to provide customized source
     extraction.
 
     Parameters
     ----------
     obj : object
         an object whose source code we will attempt to extract
     oname : str
         (optional) a name under which the object is known
 
     Returns
     -------
     src : unicode or None
 
     """
 
     if isinstance(obj, property):
         sources = []
         for attrname in ['fget', 'fset', 'fdel']:
             fn = getattr(obj, attrname)
             if fn is not None:
                 encoding = get_encoding(fn)
                 oname_prefix = ('%s.' % oname) if oname else ''
                 sources.append(cast_unicode(
                     ''.join(('# ', oname_prefix, attrname)),
                     encoding=encoding))
                 if inspect.isfunction(fn):
                     sources.append(dedent(getsource(fn)))
                 else:
                     # Default str/repr only prints function name,
                     # pretty.pretty prints module name too.
                     sources.append(cast_unicode(
                         '%s%s = %s\n' % (
                             oname_prefix, attrname, pretty(fn)),
                         encoding=encoding))
         if sources:
             return '\n'.join(sources)
         else:
             return None
 
     else:
         # Get source for non-property objects.
 
         obj = _get_wrapped(obj)
 
         try:
             src = inspect.getsource(obj)
         except TypeError:
             # The object itself provided no meaningful source, try looking for
             # its class definition instead.
             if hasattr(obj, '__class__'):
                 try:
                     src = inspect.getsource(obj.__class__)
                 except TypeError:
                     return None
 
         encoding = get_encoding(obj)
         return cast_unicode(src, encoding=encoding)
 
 
 def is_simple_callable(obj):
     """True if obj is a function ()"""
     return (inspect.isfunction(obj) or inspect.ismethod(obj) or \
             isinstance(obj, _builtin_func_type) or isinstance(obj, _builtin_meth_type))
 
 
 def getargspec(obj):
     """Wrapper around :func:`inspect.getfullargspec` on Python 3, and
     :func:inspect.getargspec` on Python 2.
 
     In addition to functions and methods, this can also handle objects with a
     ``__call__`` attribute.
     """
     if safe_hasattr(obj, '__call__') and not is_simple_callable(obj):
         obj = obj.__call__
 
     return inspect.getfullargspec(obj)
 
 
 def format_argspec(argspec):
     """Format argspect, convenience wrapper around inspect's.
 
     This takes a dict instead of ordered arguments and calls
     inspect.format_argspec with the arguments in the necessary order.
     """
     return inspect.formatargspec(argspec['args'], argspec['varargs'],
                                  argspec['varkw'], argspec['defaults'])
 
 @undoc
 def call_tip(oinfo, format_call=True):
     """DEPRECATED. Extract call tip data from an oinfo dict.
     """
     warnings.warn('`call_tip` function is deprecated as of IPython 6.0'
                   'and will be removed in future versions.', DeprecationWarning, stacklevel=2)
     # Get call definition
     argspec = oinfo.get('argspec')
     if argspec is None:
         call_line = None
     else:
         # Callable objects will have 'self' as their first argument, prune
         # it out if it's there for clarity (since users do *not* pass an
         # extra first argument explicitly).
         try:
             has_self = argspec['args'][0] == 'self'
         except (KeyError, IndexError):
             pass
         else:
             if has_self:
                 argspec['args'] = argspec['args'][1:]
 
         call_line = oinfo['name']+format_argspec(argspec)
 
     # Now get docstring.
     # The priority is: call docstring, constructor docstring, main one.
     doc = oinfo.get('call_docstring')
     if doc is None:
         doc = oinfo.get('init_docstring')
     if doc is None:
         doc = oinfo.get('docstring','')
 
     return call_line, doc
 
 
 def _get_wrapped(obj):
     """Get the original object if wrapped in one or more @decorators
 
     Some objects automatically construct similar objects on any unrecognised
     attribute access (e.g. unittest.mock.call). To protect against infinite loops,
     this will arbitrarily cut off after 100 levels of obj.__wrapped__
     attribute access. --TK, Jan 2016
     """
     orig_obj = obj
     i = 0
     while safe_hasattr(obj, '__wrapped__'):
         obj = obj.__wrapped__
         i += 1
         if i > 100:
             # __wrapped__ is probably a lie, so return the thing we started with
             return orig_obj
     return obj
 
 def find_file(obj):
     """Find the absolute path to the file where an object was defined.
 
     This is essentially a robust wrapper around `inspect.getabsfile`.
 
     Returns None if no file can be found.
 
     Parameters
     ----------
     obj : any Python object
 
     Returns
     -------
     fname : str
       The absolute path to the file where the object was defined.
     """
     obj = _get_wrapped(obj)
 
     fname = None
     try:
         fname = inspect.getabsfile(obj)
     except TypeError:
         # For an instance, the file that matters is where its class was
         # declared.
         if hasattr(obj, '__class__'):
             try:
                 fname = inspect.getabsfile(obj.__class__)
             except TypeError:
                 # Can happen for builtins
                 pass
     except:
         pass
     return cast_unicode(fname)
 
 
 def find_source_lines(obj):
     """Find the line number in a file where an object was defined.
 
     This is essentially a robust wrapper around `inspect.getsourcelines`.
 
     Returns None if no file can be found.
 
     Parameters
     ----------
     obj : any Python object
 
     Returns
     -------
     lineno : int
       The line number where the object definition starts.
     """
     obj = _get_wrapped(obj)
 
     try:
         try:
             lineno = inspect.getsourcelines(obj)[1]
         except TypeError:
             # For instances, try the class object like getsource() does
             if hasattr(obj, '__class__'):
                 lineno = inspect.getsourcelines(obj.__class__)[1]
             else:
                 lineno = None
     except:
         return None
 
     return lineno
 
 class Inspector(Colorable):
 
     def __init__(self, color_table=InspectColors,
                  code_color_table=PyColorize.ANSICodeColors,
                  scheme=None,
                  str_detail_level=0,
                  parent=None, config=None):
         super(Inspector, self).__init__(parent=parent, config=config)
         self.color_table = color_table
         self.parser = PyColorize.Parser(out='str', parent=self, style=scheme)
         self.format = self.parser.format
         self.str_detail_level = str_detail_level
         self.set_active_scheme(scheme)
 
     def _getdef(self,obj,oname=''):
         """Return the call signature for any callable object.
 
         If any exception is generated, None is returned instead and the
         exception is suppressed."""
         try:
             hdef = _render_signature(signature(obj), oname)
             return cast_unicode(hdef)
         except:
             return None
 
     def __head(self,h):
         """Return a header string with proper colors."""
         return '%s%s%s' % (self.color_table.active_colors.header,h,
                            self.color_table.active_colors.normal)
 
     def set_active_scheme(self, scheme):
         if scheme is not None:
             self.color_table.set_active_scheme(scheme)
             self.parser.color_table.set_active_scheme(scheme)
 
     def noinfo(self, msg, oname):
         """Generic message when no information is found."""
         print('No %s found' % msg, end=' ')
         if oname:
             print('for %s' % oname)
         else:
             print()
 
     def pdef(self, obj, oname=''):
         """Print the call signature for any callable object.
 
         If the object is a class, print the constructor information."""
 
         if not callable(obj):
             print('Object is not callable.')
             return
 
         header = ''
 
         if inspect.isclass(obj):
             header = self.__head('Class constructor information:\n')
 
 
         output = self._getdef(obj,oname)
         if output is None:
             self.noinfo('definition header',oname)
         else:
             print(header,self.format(output), end=' ')
 
     # In Python 3, all classes are new-style, so they all have __init__.
     @skip_doctest
     def pdoc(self, obj, oname='', formatter=None):
         """Print the docstring for any object.
 
         Optional:
         -formatter: a function to run the docstring through for specially
         formatted docstrings.
 
         Examples
         --------
 
         In [1]: class NoInit:
            ...:     pass
 
         In [2]: class NoDoc:
            ...:     def __init__(self):
            ...:         pass
 
         In [3]: %pdoc NoDoc
         No documentation found for NoDoc
 
         In [4]: %pdoc NoInit
         No documentation found for NoInit
 
         In [5]: obj = NoInit()
 
         In [6]: %pdoc obj
         No documentation found for obj
 
         In [5]: obj2 = NoDoc()
 
         In [6]: %pdoc obj2
         No documentation found for obj2
         """
 
         head = self.__head  # For convenience
         lines = []
         ds = getdoc(obj)
         if formatter:
             ds = formatter(ds).get('plain/text', ds)
         if ds:
             lines.append(head("Class docstring:"))
             lines.append(indent(ds))
         if inspect.isclass(obj) and hasattr(obj, '__init__'):
             init_ds = getdoc(obj.__init__)
             if init_ds is not None:
                 lines.append(head("Init docstring:"))
                 lines.append(indent(init_ds))
         elif hasattr(obj,'__call__'):
             call_ds = getdoc(obj.__call__)
             if call_ds:
                 lines.append(head("Call docstring:"))
                 lines.append(indent(call_ds))
 
         if not lines:
             self.noinfo('documentation',oname)
         else:
             page.page('\n'.join(lines))
 
     def psource(self, obj, oname=''):
         """Print the source code for an object."""
 
         # Flush the source cache because inspect can return out-of-date source
         linecache.checkcache()
         try:
             src = getsource(obj, oname=oname)
         except Exception:
             src = None
 
         if src is None:
             self.noinfo('source', oname)
         else:
             page.page(self.format(src))
 
     def pfile(self, obj, oname=''):
         """Show the whole file where an object was defined."""
 
         lineno = find_source_lines(obj)
         if lineno is None:
             self.noinfo('file', oname)
             return
 
         ofile = find_file(obj)
         # run contents of file through pager starting at line where the object
         # is defined, as long as the file isn't binary and is actually on the
         # filesystem.
         if ofile.endswith(('.so', '.dll', '.pyd')):
             print('File %r is binary, not printing.' % ofile)
         elif not os.path.isfile(ofile):
             print('File %r does not exist, not printing.' % ofile)
         else:
             # Print only text files, not extension binaries.  Note that
             # getsourcelines returns lineno with 1-offset and page() uses
             # 0-offset, so we must adjust.
             page.page(self.format(openpy.read_py_file(ofile, skip_encoding_cookie=False)), lineno - 1)
 
     def _format_fields(self, fields, title_width=0):
         """Formats a list of fields for display.
 
         Parameters
         ----------
         fields : list
           A list of 2-tuples: (field_title, field_content)
         title_width : int
           How many characters to pad titles to. Default to longest title.
         """
         out = []
         header = self.__head
         if title_width == 0:
             title_width = max(len(title) + 2 for title, _ in fields)
         for title, content in fields:
             if len(content.splitlines()) > 1:
                 title = header(title + ':') + '\n'
             else:
                 title = header((title + ':').ljust(title_width))
             out.append(cast_unicode(title) + cast_unicode(content))
         return "\n".join(out)
 
     def _mime_format(self, text, formatter=None):
         """Return a mime bundle representation of the input text.
 
         - if `formatter` is None, the returned mime bundle has
            a `text/plain` field, with the input text.
            a `text/html` field with a `<pre>` tag containing the input text.
 
         - if `formatter` is not None, it must be a callable transforming the
           input text into a mime bundle. Default values for `text/plain` and
           `text/html` representations are the ones described above.
 
         Note:
 
         Formatters returning strings are supported but this behavior is deprecated.
 
         """
         text = cast_unicode(text)
         defaults = {
             'text/plain': text,
             'text/html': '<pre>' + text + '</pre>'
         }
 
         if formatter is None:
             return defaults
         else:
             formatted = formatter(text)
 
             if not isinstance(formatted, dict):
                 # Handle the deprecated behavior of a formatter returning
                 # a string instead of a mime bundle.
                 return {
                     'text/plain': formatted,
                     'text/html': '<pre>' + formatted + '</pre>'
                 }
 
             else:
                 return dict(defaults, **formatted)
 
 
     def format_mime(self, bundle):
 
         text_plain = bundle['text/plain']
 
         text = ''
         heads, bodies = list(zip(*text_plain))
         _len = max(len(h) for h in heads)
 
         for head, body in zip(heads, bodies):
             body = body.strip('\n')
             delim = '\n' if '\n' in body else ' '
             text += self.__head(head+':') + (_len - len(head))*' ' +delim + body +'\n'
 
         bundle['text/plain'] = text
         return bundle
 
     def _get_info(self, obj, oname='', formatter=None, info=None, detail_level=0):
         """Retrieve an info dict and format it.
 
         Parameters
         ==========
 
         obj: any
             Object to inspect and return info from
         oname: str (default: ''):
             Name of the variable pointing to `obj`.
         formatter: callable
         info:
             already computed information
         detail_level: integer
             Granularity of detail level, if set to 1, give more information.
         """
 
         info = self._info(obj, oname=oname, info=info, detail_level=detail_level)
 
         _mime = {
             'text/plain': [],
             'text/html': '',
         }
 
         def append_field(bundle, title, key, formatter=None):
             field = info[key]
             if field is not None:
                 formatted_field = self._mime_format(field, formatter)
                 bundle['text/plain'].append((title, formatted_field['text/plain']))
                 bundle['text/html'] += '<h1>' + title + '</h1>\n' + formatted_field['text/html'] + '\n'
 
         def code_formatter(text):
             return {
                 'text/plain': self.format(text),
                 'text/html': pylight(text)
             }
 
         if info['isalias']:
             append_field(_mime, 'Repr', 'string_form')
 
         elif info['ismagic']:
             if detail_level > 0:
                 append_field(_mime, 'Source', 'source', code_formatter)
             else:
                 append_field(_mime, 'Docstring', 'docstring', formatter)
             append_field(_mime, 'File', 'file')
 
         elif info['isclass'] or is_simple_callable(obj):
             # Functions, methods, classes
             append_field(_mime, 'Signature', 'definition', code_formatter)
             append_field(_mime, 'Init signature', 'init_definition', code_formatter)
             append_field(_mime, 'Docstring', 'docstring', formatter)
             if detail_level > 0 and info['source']:
                 append_field(_mime, 'Source', 'source', code_formatter)
             else:
                 append_field(_mime, 'Init docstring', 'init_docstring', formatter)
 
             append_field(_mime, 'File', 'file')
             append_field(_mime, 'Type', 'type_name')
             append_field(_mime, 'Subclasses', 'subclasses')
 
         else:
             # General Python objects
             append_field(_mime, 'Signature', 'definition', code_formatter)
             append_field(_mime, 'Call signature', 'call_def', code_formatter)
             append_field(_mime, 'Type', 'type_name')
             append_field(_mime, 'String form', 'string_form')
 
             # Namespace
             if info['namespace'] != 'Interactive':
                 append_field(_mime, 'Namespace', 'namespace')
 
             append_field(_mime, 'Length', 'length')
             append_field(_mime, 'File', 'file')
 
             # Source or docstring, depending on detail level and whether
             # source found.
             if detail_level > 0 and info['source']:
                 append_field(_mime, 'Source', 'source', code_formatter)
             else:
                 append_field(_mime, 'Docstring', 'docstring', formatter)
 
             append_field(_mime, 'Class docstring', 'class_docstring', formatter)
             append_field(_mime, 'Init docstring', 'init_docstring', formatter)
             append_field(_mime, 'Call docstring', 'call_docstring', formatter)
 
 
         return self.format_mime(_mime)
 
     def pinfo(self, obj, oname='', formatter=None, info=None, detail_level=0, enable_html_pager=True):
         """Show detailed information about an object.
 
         Optional arguments:
 
         - oname: name of the variable pointing to the object.
 
         - formatter: callable (optional)
               A special formatter for docstrings.
 
               The formatter is a callable that takes a string as an input
               and returns either a formatted string or a mime type bundle
               in the form of a dictionary.
 
               Although the support of custom formatter returning a string
               instead of a mime type bundle is deprecated.
 
         - info: a structure with some information fields which may have been
           precomputed already.
 
         - detail_level: if set to 1, more information is given.
         """
         info = self._get_info(obj, oname, formatter, info, detail_level)
         if not enable_html_pager:
             del info['text/html']
         page.page(info)
 
     def info(self, obj, oname='', formatter=None, info=None, detail_level=0):
         """DEPRECATED. Compute a dict with detailed information about an object.
         """
         if formatter is not None:
             warnings.warn('The `formatter` keyword argument to `Inspector.info`'
                      'is deprecated as of IPython 5.0 and will have no effects.',
                       DeprecationWarning, stacklevel=2)
         return self._info(obj, oname=oname, info=info, detail_level=detail_level)
 
     def _info(self, obj, oname='', info=None, detail_level=0) -> dict:
         """Compute a dict with detailed information about an object.
 
         Parameters
         ==========
 
         obj: any
             An object to find information about
         oname: str (default: ''):
             Name of the variable pointing to `obj`.
         info: (default: None)
             A struct (dict like with attr access) with some information fields
             which may have been precomputed already.
         detail_level: int (default:0)
             If set to 1, more information is given.
 
         Returns
         =======
 
         An object info dict with known fields from `info_fields`.
         """
 
         if info is None:
             ismagic = False
             isalias = False
             ospace = ''
         else:
             ismagic = info.ismagic
             isalias = info.isalias
             ospace = info.namespace
 
         # Get docstring, special-casing aliases:
         if isalias:
             if not callable(obj):
                 try:
                     ds = "Alias to the system command:\n  %s" % obj[1]
                 except:
                     ds = "Alias: " + str(obj)
             else:
                 ds = "Alias to " + str(obj)
                 if obj.__doc__:
                     ds += "\nDocstring:\n" + obj.__doc__
         else:
             ds = getdoc(obj)
             if ds is None:
                 ds = '<no docstring>'
 
         # store output in a dict, we initialize it here and fill it as we go
         out = dict(name=oname, found=True, isalias=isalias, ismagic=ismagic, subclasses=None)
 
         string_max = 200 # max size of strings to show (snipped if longer)
         shalf = int((string_max - 5) / 2)
 
         if ismagic:
             out['type_name'] = 'Magic function'
         elif isalias:
             out['type_name'] = 'System alias'
         else:
             out['type_name'] = type(obj).__name__
 
         try:
             bclass = obj.__class__
             out['base_class'] = str(bclass)
         except:
             pass
 
         # String form, but snip if too long in ? form (full in ??)
         if detail_level >= self.str_detail_level:
             try:
                 ostr = str(obj)
                 str_head = 'string_form'
                 if not detail_level and len(ostr)>string_max:
                     ostr = ostr[:shalf] + ' <...> ' + ostr[-shalf:]
                     ostr = ("\n" + " " * len(str_head.expandtabs())).\
                             join(q.strip() for q in ostr.split("\n"))
                 out[str_head] = ostr
             except:
                 pass
 
         if ospace:
             out['namespace'] = ospace
 
         # Length (for strings and lists)
         try:
             out['length'] = str(len(obj))
         except Exception:
             pass
 
         # Filename where object was defined
         binary_file = False
         fname = find_file(obj)
         if fname is None:
             # if anything goes wrong, we don't want to show source, so it's as
             # if the file was binary
             binary_file = True
         else:
             if fname.endswith(('.so', '.dll', '.pyd')):
                 binary_file = True
             elif fname.endswith('<string>'):
                 fname = 'Dynamically generated function. No source code available.'
             out['file'] = compress_user(fname)
 
         # Original source code for a callable, class or property.
         if detail_level:
             # Flush the source cache because inspect can return out-of-date
             # source
             linecache.checkcache()
             try:
                 if isinstance(obj, property) or not binary_file:
                     src = getsource(obj, oname)
                     if src is not None:
                         src = src.rstrip()
                     out['source'] = src
 
             except Exception:
                 pass
 
         # Add docstring only if no source is to be shown (avoid repetitions).
         if ds and not self._source_contains_docstring(out.get('source'), ds):
             out['docstring'] = ds
 
         # Constructor docstring for classes
         if inspect.isclass(obj):
             out['isclass'] = True
 
             # get the init signature:
             try:
                 init_def = self._getdef(obj, oname)
             except AttributeError:
                 init_def = None
 
             # get the __init__ docstring
             try:
                 obj_init = obj.__init__
             except AttributeError:
                 init_ds = None
             else:
                 if init_def is None:
                     # Get signature from init if top-level sig failed.
                     # Can happen for built-in types (list, etc.).
                     try:
                         init_def = self._getdef(obj_init, oname)
                     except AttributeError:
                         pass
                 init_ds = getdoc(obj_init)
                 # Skip Python's auto-generated docstrings
                 if init_ds == _object_init_docstring:
                     init_ds = None
 
             if init_def:
                 out['init_definition'] = init_def
 
             if init_ds:
                 out['init_docstring'] = init_ds
 
             names = [sub.__name__ for sub in obj.__subclasses__()]
-            all_names = ', '.join(names)
+            if len(names) < 10:
+                all_names = ', '.join(names)
+            else:
+                all_names = ', '.join(names[:10]+['...'])
             out['subclasses'] = all_names
         # and class docstring for instances:
         else:
             # reconstruct the function definition and print it:
             defln = self._getdef(obj, oname)
             if defln:
                 out['definition'] = defln
 
             # First, check whether the instance docstring is identical to the
             # class one, and print it separately if they don't coincide.  In
             # most cases they will, but it's nice to print all the info for
             # objects which use instance-customized docstrings.
             if ds:
                 try:
                     cls = getattr(obj,'__class__')
                 except:
                     class_ds = None
                 else:
                     class_ds = getdoc(cls)
                 # Skip Python's auto-generated docstrings
                 if class_ds in _builtin_type_docstrings:
                     class_ds = None
                 if class_ds and ds != class_ds:
                     out['class_docstring'] = class_ds
 
             # Next, try to show constructor docstrings
             try:
                 init_ds = getdoc(obj.__init__)
                 # Skip Python's auto-generated docstrings
                 if init_ds == _object_init_docstring:
                     init_ds = None
             except AttributeError:
                 init_ds = None
             if init_ds:
                 out['init_docstring'] = init_ds
 
             # Call form docstring for callable instances
             if safe_hasattr(obj, '__call__') and not is_simple_callable(obj):
                 call_def = self._getdef(obj.__call__, oname)
                 if call_def and (call_def != out.get('definition')):
                     # it may never be the case that call def and definition differ,
                     # but don't include the same signature twice
                     out['call_def'] = call_def
                 call_ds = getdoc(obj.__call__)
                 # Skip Python's auto-generated docstrings
                 if call_ds == _func_call_docstring:
                     call_ds = None
                 if call_ds:
                     out['call_docstring'] = call_ds
 
         # Compute the object's argspec as a callable.  The key is to decide
         # whether to pull it from the object itself, from its __init__ or
         # from its __call__ method.
 
         if inspect.isclass(obj):
             # Old-style classes need not have an __init__
             callable_obj = getattr(obj, "__init__", None)
         elif callable(obj):
             callable_obj = obj
         else:
             callable_obj = None
 
         if callable_obj is not None:
             try:
                 argspec = getargspec(callable_obj)
             except Exception:
                 # For extensions/builtins we can't retrieve the argspec
                 pass
             else:
                 # named tuples' _asdict() method returns an OrderedDict, but we
                 # we want a normal
                 out['argspec'] = argspec_dict = dict(argspec._asdict())
                 # We called this varkw before argspec became a named tuple.
                 # With getfullargspec it's also called varkw.
                 if 'varkw' not in argspec_dict:
                     argspec_dict['varkw'] = argspec_dict.pop('keywords')
 
         return object_info(**out)
 
     @staticmethod
     def _source_contains_docstring(src, doc):
         """
         Check whether the source *src* contains the docstring *doc*.
 
         This is is helper function to skip displaying the docstring if the
         source already contains it, avoiding repetition of information.
         """
         try:
             def_node, = ast.parse(dedent(src)).body
             return ast.get_docstring(def_node) == doc
         except Exception:
             # The source can become invalid or even non-existent (because it
             # is re-fetched from the source file) so the above code fail in
             # arbitrary ways.
             return False
 
     def psearch(self,pattern,ns_table,ns_search=[],
                 ignore_case=False,show_all=False):
         """Search namespaces with wildcards for objects.
 
         Arguments:
 
         - pattern: string containing shell-like wildcards to use in namespace
           searches and optionally a type specification to narrow the search to
           objects of that type.
 
         - ns_table: dict of name->namespaces for search.
 
         Optional arguments:
 
           - ns_search: list of namespace names to include in search.
 
           - ignore_case(False): make the search case-insensitive.
 
           - show_all(False): show all names, including those starting with
             underscores.
         """
         #print 'ps pattern:<%r>' % pattern # dbg
 
         # defaults
         type_pattern = 'all'
         filter = ''
 
         cmds = pattern.split()
         len_cmds  =  len(cmds)
         if len_cmds == 1:
             # Only filter pattern given
             filter = cmds[0]
         elif len_cmds == 2:
             # Both filter and type specified
             filter,type_pattern = cmds
         else:
             raise ValueError('invalid argument string for psearch: <%s>' %
                              pattern)
 
         # filter search namespaces
         for name in ns_search:
             if name not in ns_table:
                 raise ValueError('invalid namespace <%s>. Valid names: %s' %
                                  (name,ns_table.keys()))
 
         #print 'type_pattern:',type_pattern # dbg
         search_result, namespaces_seen = set(), set()
         for ns_name in ns_search:
             ns = ns_table[ns_name]
             # Normally, locals and globals are the same, so we just check one.
             if id(ns) in namespaces_seen:
                 continue
             namespaces_seen.add(id(ns))
             tmp_res = list_namespace(ns, type_pattern, filter,
                                     ignore_case=ignore_case, show_all=show_all)
             search_result.update(tmp_res)
 
         page.page('\n'.join(sorted(search_result)))
 
 
 def _render_signature(obj_signature, obj_name):
     """
     This was mostly taken from inspect.Signature.__str__.
     Look there for the comments.
     The only change is to add linebreaks when this gets too long.
     """
     result = []
     pos_only = False
     kw_only = True
     for param in obj_signature.parameters.values():
         if param.kind == inspect._POSITIONAL_ONLY:
             pos_only = True
         elif pos_only:
             result.append('/')
             pos_only = False
 
         if param.kind == inspect._VAR_POSITIONAL:
             kw_only = False
         elif param.kind == inspect._KEYWORD_ONLY and kw_only:
             result.append('*')
             kw_only = False
 
         result.append(str(param))
 
     if pos_only:
         result.append('/')
 
     # add up name, parameters, braces (2), and commas
     if len(obj_name) + sum(len(r) + 2 for r in result) > 75:
         # This doesn’t fit behind “Signature: ” in an inspect window.
         rendered = '{}(\n{})'.format(obj_name, ''.join('    {},\n'.format(result)))
     else:
         rendered = '{}({})'.format(obj_name, ', '.join(result))
 
     if obj_signature.return_annotation is not inspect._empty:
         anno = inspect.formatannotation(obj_signature.return_annotation)
         rendered += ' -> {}'.format(anno)
 
     return rendered

docs/source/whatsnew/version7.rst

@@ -1,354 +1,406 b''
 ============
  7.x Series
 ============
 
+.. _whatsnew720:
+
+IPython 7.2.0
+=============
+
+IPython 7.2.0 bring minor fixes, improvement and new options.
+
+ - Fix a bug preventing to enable PySide2 gui integration :ghpull:`11464`
+ - Run CI on Mac OS ! :ghpull:`11471`
+ - Fix IPython "Demo" mode. :ghpull:`11498`
+ - Fix ``%run`` magic  with path in name :ghpull:`11499`
+ - Fix: add CWD to sys.path *after* stdlib :ghpull:`11502`
+ - Better rendering of signatures, especially long ones. :ghpull:`11505`
+ - Re enable jedi by default if installed :ghpull:`11506`
+ - Add New ``minimal`` exception reporting mode (useful for educational purpose). See :ghpull:`11509`
+
+
+Added ability to show subclasses when using pinfo and other utilities
+---------------------------------------------------------------------
+
+When using ``?``/``??`` on a class, IPython will now list the first 10 subclasses.
+
+Special Thanks to Chris Mentzel of the Moore Foundation for this feature, Chris
+is one of the people who played a critical role in IPython/Jupyter getting
+funding.
+
+We are grateful for all the help Chris gave us through the years, We are now
+proud to have code contributed by Chris in IPython.
+
+OSMagics.cd_force_quiet configuration option
+--------------------------------------------
+
+You can set this option to force the %cd magic to behave as if ``-q`` was passed:
+::
+
+    In [1]: cd /
+    /
+
+    In [2]: %config OSMagics.cd_force_quiet = True
+
+    In [3]: cd /tmp
+
+    In [4]:
+
+See :ghpull:`11491`
+
+In vi editing mode, whether the prompt includes the current vi mode can now be configured
+-----------------------------------------------------------------------------------------
+
+Set the ``TerminalInteractiveShell.prompt_includes_vi_mode`` to a boolean value
+(default: True) to control this feature. See :ghpull:`11492`
+
 .. _whatsnew710:
 
 IPython 7.1.0
 =============
 
 IPython 7.1.0 is the first minor release after 7.0.0 and mostly bring fixes to
 new feature, internal refactor and regressions that happen during the 6.x->7.x
 transition. It also bring **Compatibility with Python 3.7.1**, as were
 unwillingly relying on a bug in CPython.
 
 New Core Dev:
 
  - We welcome Jonathan Slenders to the commiters. Jonathan has done a fantastic
    work on Prompt toolkit, and we'd like to recognise his impact by giving him
    commit rights. :ghissue:`11397`
 
 Notables Changes
 
  - Major update of "latex to unicode" tab completion map (see below)
 
 Notable New Features:
 
  - Restore functionality and documentation of the **sphinx directive**, which
    is now stricter (fail on error by default), gained configuration options,
    have a brand new documentation page :ref:`ipython_directive`, which need
    some cleanup. It is also now *tested* so we hope to have less regressions.
    :ghpull:`11402`
 
  - ``IPython.display.Video`` now supports ``width`` and ``height`` arguments,
    allowing a custom width and height to be set instead of using the video's
    width and height. :ghpull:`11353`
 
  - Warn when using ``HTML('<iframe>')`` instead of ``IFrame`` :ghpull:`11350`
 
  - Allow Dynamic switching of editing mode between vi/emacs and show
    normal/input mode in prompt when using vi. :ghpull:`11390`. Use ``%config
    TerminalInteractiveShell.editing_mode = 'vi'`` or ``%config
    TerminalInteractiveShell.editing_mode = 'emacs'`` to dynamically spwitch
 
 
 Notable Fixes:
 
  - Fix entering of **multi-line block in terminal** IPython, and various
    crashes in the new input transformation machinery :ghpull:`11354`,
    :ghpull:`11356`, :ghpull:`11358`, these ones also fix a **Compatibility but
    with Python 3.7.1**.
 
  - Fix moving through generator stack in ipdb :ghpull:`11266`
 
  - Magics arguments now support quoting. :ghpull:`11330`
 
  - Re-add ``rprint`` and ``rprinte`` aliases. :ghpull:`11331`
 
  - Remove implicit dependency to ``ipython_genutils`` :ghpull:`11317`
 
  - Make ``nonlocal`` raise ``SyntaxError`` instead of silently failing in async
    mode. :ghpull:`11382`
 
  - Fix mishandling of magics and ``= !`` assignment just after a dedent in
    nested code blocks :ghpull:`11418`
 
  - Fix instructions for custom shortcuts :ghpull:`11426`
 
 
 Notable Internals improvements:
 
  - Use of ``os.scandir`` (Python 3 only) to speedup some file system operations.
    :ghpull:`11365`
 
  - use ``perf_counter`` instead of ``clock`` for more precise
    timing result with ``%time`` :ghpull:`11376`
 
 Many thanks to all the contributors and in particular to ``bartskowron``, and
 ``tonyfast`` who handled a pretty complicated bugs in the input machinery. We
 had a number of first time contributors and maybe hacktoberfest participant that
 made significant contributions, and helped us free some time to focus on more
 complicated bugs.
 
 You
 can see all the closed issues and Merged PR, new features and fixes `here
 <https://github.com/ipython/ipython/issues?utf8=%E2%9C%93&q=+is%3Aclosed+milestone%3A7.1+>`_.
 
 Unicode Completion update
 -------------------------
 
 In IPython 7.1 the Unicode completion map has been updated and synchronized with
 the Julia language.
 
 Added and removed character characters:
 
  ``\jmath`` (``ȷ``), ``\\underleftrightarrow`` (U+034D, combining) have been
  added, while ``\\textasciicaron`` have been removed
 
 Some sequence have seen their prefix removed:
 
  - 6 characters ``\text...<tab>`` should now be inputed with ``\...<tab>`` directly,
  - 45 characters ``\Elz...<tab>`` should now be inputed with ``\...<tab>`` directly,
  - 65 characters ``\B...<tab>`` should now be inputed with ``\...<tab>`` directly,
  - 450 characters ``\m...<tab>`` should now be inputed with ``\...<tab>`` directly,
 
 Some sequence have seen their prefix shortened:
 
  - 5 characters ``\mitBbb...<tab>`` should now be inputed with ``\bbi...<tab>`` directly,
  - 52 characters ``\mit...<tab>`` should now be inputed with ``\i...<tab>`` directly,
  - 216 characters ``\mbfit...<tab>`` should now be inputed with ``\bi...<tab>`` directly,
  - 222 characters ``\mbf...<tab>`` should now be inputed with ``\b...<tab>`` directly,
 
 A couple of character had their sequence simplified:
 
  - ``ð``, type ``\dh<tab>``, instead of ``\eth<tab>``
  - ``ħ``, type ``\hbar<tab>``, instead of ``\Elzxh<tab>``
  - ``ɸ``, type ``\ltphi<tab>``, instead of ``\textphi<tab>``
  - ``ϴ``, type ``\varTheta<tab>``, instead of ``\textTheta<tab>``
  - ``ℇ``, type ``\eulermascheroni<tab>``, instead of ``\Eulerconst<tab>``
  - ``ℎ``, type ``\planck<tab>``, instead of ``\Planckconst<tab>``
 
  - U+0336 (COMBINING LONG STROKE OVERLAY), type ``\strike<tab>``, instead of ``\Elzbar<tab>``.
 
 A couple of sequences have been updated:
 
  - ``\varepsilon`` now give ``ɛ`` (GREEK SMALL LETTER EPSILON) instead of ``ε`` (GREEK LUNATE EPSILON SYMBOL),
  - ``\underbar`` now give U+0331 (COMBINING MACRON BELOW) instead of U+0332 (COMBINING LOW LINE).
 
 
 .. _whatsnew700:
 
 IPython 7.0.0
 =============
 
 Released Thursday September 27th, 2018
 
 IPython 7 include major features improvement as you can read in the following
 changelog. This is also the second major version of IPython to support only
 Python 3 – starting at Python 3.4. Python 2 is still community supported
 on the bugfix only 5.x branch, but we remind you that Python 2 "end of life"
 is on Jan 1st 2020.
 
 We were able to backport bug fixes to the 5.x branch thanks to our backport bot which
 backported more than `70 Pull-Requests
 <https://github.com/ipython/ipython/pulls?page=3&q=is%3Apr+sort%3Aupdated-desc+author%3Aapp%2Fmeeseeksdev++5.x&utf8=%E2%9C%93>`_, but there are still many PRs that required manually work, and this is an area of the project were you can easily contribute by looking for `PRs still needed backport <https://github.com/ipython/ipython/issues?q=label%3A%22Still+Needs+Manual+Backport%22+is%3Aclosed+sort%3Aupdated-desc>`_
 
 IPython 6.x branch will likely not see any further release unless critical
 bugs are found.
 
 Make sure you have pip > 9.0 before upgrading. You should be able to update by simply running
 
 .. code::
 
     pip install ipython --upgrade
 
 .. only:: ipydev
 
   If you are trying to install or update an ``alpha``, ``beta``, or ``rc``
   version, use pip ``--pre`` flag.
 
   .. code::
 
       pip install ipython --upgrade --pre
 
 
 Or if you have conda installed: 
 
 .. code::
    
    conda install ipython
 
 
 
 Prompt Toolkit 2.0
 ------------------
 
 IPython 7.0+ now uses ``prompt_toolkit 2.0``, if you still need to use earlier
 ``prompt_toolkit`` version you may need to pin IPython to ``<7.0``.
 
 Autowait: Asynchronous REPL
 ---------------------------
 
 Staring with IPython 7.0 and on Python 3.6+, IPython can automatically await
 code at top level, you should not need to access an event loop or runner
 yourself. To know more read the :ref:`autoawait` section of our docs, see
 :ghpull:`11265` or try the following code::
 
     Python 3.6.0
     Type 'copyright', 'credits' or 'license' for more information
     IPython 7.0.0 -- An enhanced Interactive Python. Type '?' for help.
 
     In [1]: import aiohttp
        ...: result = aiohttp.get('https://api.github.com')
 
     In [2]: response = await result
     <pause for a few 100s ms>
 
     In [3]: await response.json()
     Out[3]:
     {'authorizations_url': 'https://api.github.com/authorizations',
      'code_search_url': 'https://api.github.com/search/code?q={query}{&page,per_page,sort,order}',
     ...
     }
 
 .. note::
 
    Async integration is experimental code, behavior may change or be removed
    between Python and IPython versions without warnings.
 
 Integration is by default with `asyncio`, but other libraries can be configured,
 like ``curio`` or ``trio``, to improve concurrency in the REPL::
 
     In [1]: %autoawait trio
 
     In [2]: import trio
 
     In [3]: async def child(i):
        ...:     print("   child %s goes to sleep"%i)
        ...:     await trio.sleep(2)
        ...:     print("   child %s wakes up"%i)
 
     In [4]: print('parent start')
        ...: async with trio.open_nursery() as n:
        ...:     for i in range(3):
        ...:         n.spawn(child, i)
        ...: print('parent end')
     parent start
        child 2 goes to sleep
        child 0 goes to sleep
        child 1 goes to sleep
        <about 2 seconds pause>
        child 2 wakes up
        child 1 wakes up
        child 0 wakes up
     parent end
 
 See :ref:`autoawait` for more information.
 
 
 Asynchronous code in a Notebook interface or any other frontend using the
 Jupyter Protocol will need further updates of the IPykernel package.
 
 Non-Asynchronous code
 ~~~~~~~~~~~~~~~~~~~~~
 
 As the internal API of IPython is now asynchronous, IPython needs to run under
 an event loop. In order to allow many workflows, (like using the :magic:`%run`
 magic, or copy_pasting code that explicitly starts/stop event loop), when
 top-level code is detected as not being asynchronous, IPython code is advanced
 via a pseudo-synchronous runner, and may not advance pending tasks.
 
 Change to Nested Embed
 ~~~~~~~~~~~~~~~~~~~~~~
 
 The introduction of the ability to run async code had some effect on the
 ``IPython.embed()`` API. By default embed will not allow you to run asynchronous
 code unless a event loop is specified.
 
 Effects on Magics
 ~~~~~~~~~~~~~~~~~
 
 Some magics will not work with Async, and will need updates. Contribution
 welcome.
 
 Expected Future changes
 ~~~~~~~~~~~~~~~~~~~~~~~
 
 We expect more internal but public IPython function to become ``async``, and
 will likely end up having a persisting event loop while IPython is running.
 
 Thanks
 ~~~~~~
 
 This took more than a year in the making, and the code was rebased a number of
 time leading to commit authorship that may have been lost in the final
 Pull-Request. Huge thanks to many people for contribution, discussion, code,
 documentation, use-case: dalejung, danielballan, ellisonbg, fperez, gnestor,
 minrk, njsmith, pganssle, tacaswell, takluyver , vidartf ... And many others.
 
 
 Autoreload Improvement
 ----------------------
 
 The magic :magic:`%autoreload 2 <autoreload>` now captures new methods added to
 classes. Earlier, only methods existing as of the initial import were being
 tracked and updated.  
 
 This new feature helps dual environment development - Jupyter+IDE - where the
 code gradually moves from notebook cells to package files, as it gets
 structured.
 
 **Example**: An instance of the class ``MyClass`` will be able to access the
 method ``cube()`` after it is uncommented and the file ``file1.py`` saved on
 disk.
 
 
 .. code::
 
    # notebook
 
    from mymodule import MyClass
    first = MyClass(5)
 
 .. code::
 
    # mymodule/file1.py
 
    class MyClass:
 
        def __init__(self, a=10):
            self.a = a
 
        def square(self):
            print('compute square')
            return self.a*self.a
 
        # def cube(self):
        #     print('compute cube')
        #     return self.a*self.a*self.a
 
 
 
 
 Misc
 ----
 
 The autoindent feature that was deprecated in 5.x was re-enabled and
 un-deprecated in :ghpull:`11257`
 
 Make :magic:`%run -n -i ... <run>` work correctly. Earlier, if :magic:`%run` was
 passed both arguments, ``-n`` would be silently ignored. See :ghpull:`10308`
 
 
 The :cellmagic:`%%script` (as well as :cellmagic:`%%bash`,
 :cellmagic:`%%ruby`... ) cell magics now raise by default if the return code of
 the given code is non-zero (thus halting execution of further cells in a
 notebook). The behavior can be disable by passing the ``--no-raise-error`` flag.
 
 
 Deprecations
 ------------
 
 A couple of unused function and methods have been deprecated and will be removed
 in future versions:
 
   - ``IPython.utils.io.raw_print_err``
   - ``IPython.utils.io.raw_print``
 
   
 Backwards incompatible changes
 ------------------------------
 
 * The API for transforming input before it is parsed as Python code has been
   completely redesigned, and any custom input transformations will need to be
   rewritten. See :doc:`/config/inputtransforms` for details of the new API.