# -*- coding: utf-8 -*- """Main IPython class.""" #----------------------------------------------------------------------------- # Copyright (C) 2001 Janko Hauser # Copyright (C) 2001-2007 Fernando Perez. # 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. #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Imports #----------------------------------------------------------------------------- from __future__ import absolute_import from __future__ import print_function import __builtin__ as builtin_mod import __future__ import abc import ast import atexit import os import re import runpy import sys import tempfile import types from io import open as io_open from IPython.config.configurable import SingletonConfigurable from IPython.core import debugger, oinspect from IPython.core import magic from IPython.core import page from IPython.core import prefilter from IPython.core import shadowns from IPython.core import ultratb from IPython.core.alias import AliasManager, AliasError from IPython.core.autocall import ExitAutocall from IPython.core.builtin_trap import BuiltinTrap from IPython.core.compilerop import CachingCompiler, check_linecache_ipython from IPython.core.display_trap import DisplayTrap from IPython.core.displayhook import DisplayHook from IPython.core.displaypub import DisplayPublisher from IPython.core.error import UsageError from IPython.core.extensions import ExtensionManager from IPython.core.fakemodule import FakeModule, init_fakemod_dict from IPython.core.formatters import DisplayFormatter from IPython.core.history import HistoryManager from IPython.core.inputsplitter import IPythonInputSplitter, 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.pylabtools import pylab_activate from IPython.core.prompts import PromptManager from IPython.lib.latextools import LaTeXTool from IPython.testing.skipdoctest import skip_doctest from IPython.utils import PyColorize from IPython.utils import io from IPython.utils import py3compat from IPython.utils import openpy from IPython.utils.decorators import undoc from IPython.utils.doctestreload import doctest_reload from IPython.utils.io import ask_yes_no from IPython.utils.ipstruct import Struct from IPython.utils.path import get_home_dir, get_ipython_dir, get_py_filename, unquote_filename from IPython.utils.pickleshare import PickleShareDB from IPython.utils.process import system, getoutput from IPython.utils.strdispatch import StrDispatch from IPython.utils.syspathcontext import prepended_to_syspath from IPython.utils.text import (format_screen, LSString, SList, DollarFormatter) from IPython.utils.traitlets import (Integer, CBool, CaselessStrEnum, Enum, List, Unicode, Instance, Type) from IPython.utils.warn import warn, error import IPython.core.hooks #----------------------------------------------------------------------------- # Globals #----------------------------------------------------------------------------- # compiled regexps for autoindent management dedent_re = re.compile(r'^\s+raise|^\s+return|^\s+pass') #----------------------------------------------------------------------------- # Utilities #----------------------------------------------------------------------------- @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 @undoc class NoOpContext(object): def __enter__(self): pass def __exit__(self, type, value, traceback): pass no_op_context = NoOpContext() class SpaceInInput(Exception): pass @undoc class Bunch: pass def get_default_colors(): if sys.platform=='darwin': return "LightBG" elif os.name=='nt': return 'Linux' else: return 'Linux' class SeparateUnicode(Unicode): """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) class ReadlineNoRecord(object): """Context manager to execute some code, then reload readline history so that interactive input to the code doesn't appear when pressing up.""" def __init__(self, shell): self.shell = shell self._nested_level = 0 def __enter__(self): if self._nested_level == 0: try: self.orig_length = self.current_length() self.readline_tail = self.get_readline_tail() except (AttributeError, IndexError): # Can fail with pyreadline self.orig_length, self.readline_tail = 999999, [] self._nested_level += 1 def __exit__(self, type, value, traceback): self._nested_level -= 1 if self._nested_level == 0: # Try clipping the end if it's got longer try: e = self.current_length() - self.orig_length if e > 0: for _ in range(e): self.shell.readline.remove_history_item(self.orig_length) # If it still doesn't match, just reload readline history. if self.current_length() != self.orig_length \ or self.get_readline_tail() != self.readline_tail: self.shell.refill_readline_hist() except (AttributeError, IndexError): pass # Returning False will cause exceptions to propagate return False def current_length(self): return self.shell.readline.get_current_history_length() def get_readline_tail(self, n=10): """Get the last n items in readline history.""" end = self.shell.readline.get_current_history_length() + 1 start = max(end-n, 1) ghi = self.shell.readline.get_history_item return [ghi(x) for x in range(start, end)] #----------------------------------------------------------------------------- # Main IPython class #----------------------------------------------------------------------------- class InteractiveShell(SingletonConfigurable): """An enhanced, interactive shell for Python.""" _instance = None ast_transformers = List([], config=True, help= """ A list of ast.NodeTransformer subclass instances, which will be applied to user input before code is run. """ ) autocall = Enum((0,1,2), default_value=0, config=True, 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). """ ) # TODO: remove all autoindent logic and put into frontends. # We can't do this yet because even runlines uses the autoindent. autoindent = CBool(True, config=True, help= """ Autoindent IPython code entered interactively. """ ) automagic = CBool(True, config=True, help= """ Enable magic commands to be called without the leading %. """ ) cache_size = Integer(1000, config=True, 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 20 (if you provide a value less than 20, 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 """ ) color_info = CBool(True, config=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. """ ) colors = CaselessStrEnum(('NoColor','LightBG','Linux'), default_value=get_default_colors(), config=True, help="Set the color scheme (NoColor, Linux, or LightBG)." ) colors_force = CBool(False, help= """ Force use of ANSI color codes, regardless of OS and readline availability. """ # FIXME: This is essentially a hack to allow ZMQShell to show colors # without readline on Win32. When the ZMQ formatting system is # refactored, this should be removed. ) debug = CBool(False, config=True) deep_reload = CBool(False, config=True, help= """ Enable deep (recursive) reloading by default. IPython can use the deep_reload module which reloads changes in modules recursively (it replaces the reload() function, so you don't need to change anything to use it). deep_reload() forces a full reload of modules whose code may have changed, which the default reload() function does not. When deep_reload is off, IPython will use the normal reload(), but deep_reload will still be available as dreload(). """ ) disable_failing_post_execute = CBool(False, config=True, help="Don't call post-execute functions that have failed in the past." ) display_formatter = Instance(DisplayFormatter) displayhook_class = Type(DisplayHook) display_pub_class = Type(DisplayPublisher) data_pub_class = None exit_now = CBool(False) exiter = Instance(ExitAutocall) def _exiter_default(self): return ExitAutocall(self) # Monotonically increasing execution counter execution_count = Integer(1) filename = Unicode("") ipython_dir= Unicode('', config=True) # Set to get_ipython_dir() in __init__ # Input splitter, to split entire cells of input into either individual # interactive statements or whole blocks. input_splitter = Instance('IPython.core.inputsplitter.IPythonInputSplitter', (), {}) logstart = CBool(False, config=True, help= """ Start logging to the default log file. """ ) logfile = Unicode('', config=True, help= """ The name of the logfile to use. """ ) logappend = Unicode('', config=True, help= """ Start logging to the given file in append mode. """ ) object_info_string_level = Enum((0,1,2), default_value=0, config=True) pdb = CBool(False, config=True, help= """ Automatically call the pdb debugger after every exception. """ ) multiline_history = CBool(sys.platform != 'win32', config=True, help="Save multi-line entries as one entry in readline history" ) # deprecated prompt traits: prompt_in1 = Unicode('In [\\#]: ', config=True, help="Deprecated, use PromptManager.in_template") prompt_in2 = Unicode(' .\\D.: ', config=True, help="Deprecated, use PromptManager.in2_template") prompt_out = Unicode('Out[\\#]: ', config=True, help="Deprecated, use PromptManager.out_template") prompts_pad_left = CBool(True, config=True, help="Deprecated, use PromptManager.justify") def _prompt_trait_changed(self, name, old, new): table = { 'prompt_in1' : 'in_template', 'prompt_in2' : 'in2_template', 'prompt_out' : 'out_template', 'prompts_pad_left' : 'justify', } warn("InteractiveShell.{name} is deprecated, use PromptManager.{newname}".format( name=name, newname=table[name]) ) # protect against weird cases where self.config may not exist: if self.config is not None: # propagate to corresponding PromptManager trait setattr(self.config.PromptManager, table[name], new) _prompt_in1_changed = _prompt_trait_changed _prompt_in2_changed = _prompt_trait_changed _prompt_out_changed = _prompt_trait_changed _prompt_pad_left_changed = _prompt_trait_changed show_rewritten_input = CBool(True, config=True, help="Show rewritten input, e.g. for autocall." ) quiet = CBool(False, config=True) history_length = Integer(10000, config=True) # The readline stuff will eventually be moved to the terminal subclass # but for now, we can't do that as readline is welded in everywhere. readline_use = CBool(True, config=True) readline_remove_delims = Unicode('-/~', config=True) readline_delims = Unicode() # set by init_readline() # don't use \M- bindings by default, because they # conflict with 8-bit encodings. See gh-58,gh-88 readline_parse_and_bind = List([ 'tab: complete', '"\C-l": clear-screen', 'set show-all-if-ambiguous on', '"\C-o": tab-insert', '"\C-r": reverse-search-history', '"\C-s": forward-search-history', '"\C-p": history-search-backward', '"\C-n": history-search-forward', '"\e[A": history-search-backward', '"\e[B": history-search-forward', '"\C-k": kill-line', '"\C-u": unix-line-discard', ], allow_none=False, config=True) ast_node_interactivity = Enum(['all', 'last', 'last_expr', 'none'], default_value='last_expr', config=True, help=""" 'all', 'last', 'last_expr' or 'none', specifying which nodes should be run interactively (displaying output from expressions).""") # 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', config=True) separate_out = SeparateUnicode('', config=True) separate_out2 = SeparateUnicode('', config=True) wildcards_case_sensitive = CBool(True, config=True) xmode = CaselessStrEnum(('Context','Plain', 'Verbose'), default_value='Context', config=True) # Subcomponents of InteractiveShell alias_manager = Instance('IPython.core.alias.AliasManager') prefilter_manager = Instance('IPython.core.prefilter.PrefilterManager') builtin_trap = Instance('IPython.core.builtin_trap.BuiltinTrap') display_trap = Instance('IPython.core.display_trap.DisplayTrap') extension_manager = Instance('IPython.core.extensions.ExtensionManager') payload_manager = Instance('IPython.core.payload.PayloadManager') history_manager = Instance('IPython.core.history.HistoryManager') magics_manager = Instance('IPython.core.magic.MagicsManager') profile_dir = Instance('IPython.core.application.ProfileDir') @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 = Instance(dict) # Tracks any GUI loop loaded for pylab pylab_gui_select = None def __init__(self, config=None, ipython_dir=None, profile_dir=None, user_module=None, user_ns=None, custom_exceptions=((), None)): # This is where traits with a config_key argument are updated # from the values on config. super(InteractiveShell, self).__init__(config=config) 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_pushd_popd_magic() # self.init_traceback_handlers use to be here, but we moved it below # because it and init_io have to come after init_readline. self.init_user_ns() self.init_logger() self.init_alias() self.init_builtins() # The following was in post_config_initialization self.init_inspector() # init_readline() must come before init_io(), because init_io uses # readline related things. self.init_readline() # We save this here in case user code replaces raw_input, but it needs # to be after init_readline(), because PyPy's readline works by replacing # raw_input. if py3compat.PY3: self.raw_input_original = input else: self.raw_input_original = raw_input # init_completer must come after init_readline, because it needs to # know whether readline is present or not system-wide to configure the # completers, since the completion machinery can now operate # independently of readline (e.g. over the network) 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_reload_doctest() self.init_latextool() self.init_magics() self.init_logstart() self.init_pdb() self.init_extension_manager() self.init_payload() self.hooks.late_startup_hook() atexit.register(self.atexit_operations) def get_ipython(self): """Return the currently running IPython instance.""" return self #------------------------------------------------------------------------- # Trait changed handlers #------------------------------------------------------------------------- def _ipython_dir_changed(self, name, new): if not os.path.isdir(new): os.makedirs(new, mode = 0o777) def set_autoindent(self,value=None): """Set the autoindent flag, checking for readline support. If called with no arguments, it acts as a toggle.""" if value != 0 and not self.has_readline: if os.name == 'posix': warn("The auto-indent feature requires the readline library") self.autoindent = 0 return if value is None: self.autoindent = not self.autoindent else: self.autoindent = value #------------------------------------------------------------------------- # 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 = CachingCompiler() # 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. self.tempfiles = [] # Keep track of readline usage (later set by init_readline) self.has_readline = False # keep track of where we started running (mainly for crash post-mortem) # This is not being used anywhere currently. self.starting_dir = os.getcwdu() # 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' def init_syntax_highlighting(self): # Python source parser/formatter for syntax highlighting pyformat = PyColorize.Parser().format self.pycolorize = lambda src: pyformat(src,'str',self.colors) 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 # In 0.11 we introduced '__IPYTHON__active' as an integer we'd try to # manage on enter/exit, but with all our shells it's virtually # impossible to get all the cases right. We're leaving the name in for # those who adapted their codes to check for this flag, but will # eventually remove it after a few more releases. builtin_mod.__dict__['__IPYTHON__active'] = \ 'Deprecated, check for __IPYTHON__' self.builtin_trap = BuiltinTrap(shell=self) def init_inspector(self): # Object inspector self.inspector = oinspect.Inspector(oinspect.InspectColors, PyColorize.ANSICodeColors, 'NoColor', self.object_info_string_level) def init_io(self): # This will just use sys.stdout and sys.stderr. If you want to # override sys.stdout and sys.stderr themselves, you need to do that # *before* instantiating this class, because io holds onto # references to the underlying streams. if (sys.platform == 'win32' or sys.platform == 'cli') and self.has_readline: io.stdout = io.stderr = io.IOStream(self.readline._outputfile) else: io.stdout = io.IOStream(sys.stdout) io.stderr = io.IOStream(sys.stderr) def init_prompts(self): self.prompt_manager = PromptManager(shell=self, config=self.config) self.configurables.append(self.prompt_manager) # 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(config=self.config) self.configurables.append(self.display_formatter) def init_display_pub(self): self.display_pub = self.display_pub_class(config=self.config) 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(config=self.config) self.configurables.append(self.data_pub) def init_displayhook(self): # Initialize displayhook, set in/out prompts and printing system self.displayhook = self.displayhook_class( config=self.config, 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) def init_reload_doctest(self): # Do a proper resetting of doctest, including the necessary displayhook # monkeypatching try: doctest_reload() except ImportError: warn("doctest module does not exist.") def init_latextool(self): """Configure LaTeXTool.""" cfg = LaTeXTool.instance(config=self.config) if cfg not in self.configurables: self.configurables.append(cfg) def init_virtualenv(self): """Add a 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 if sys.executable.startswith(os.environ['VIRTUAL_ENV']): # Running properly in the virtualenv, don't need to do anything return warn("Attempting to work in a virtualenv. If you encounter problems, please " "install IPython inside the virtualenv.") if sys.platform == "win32": virtual_env = os.path.join(os.environ['VIRTUAL_ENV'], 'Lib', 'site-packages') else: virtual_env = os.path.join(os.environ['VIRTUAL_ENV'], 'lib', 'python%d.%d' % sys.version_info[:2], 'site-packages') 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 = {} self._orig_sys_module_state['stdin'] = sys.stdin self._orig_sys_module_state['stdout'] = sys.stdout self._orig_sys_module_state['stderr'] = sys.stderr self._orig_sys_module_state['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.iteritems(): 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 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) 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 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) def register_post_execute(self, func): """Register a function for calling after code execution. """ if not callable(func): raise ValueError('argument %s must be callable' % func) self._post_execute[func] = True #------------------------------------------------------------------------- # Things related to the "main" module #------------------------------------------------------------------------- def new_main_mod(self,ns=None): """Return a new 'main' module object for user code execution. """ main_mod = self._user_main_module init_fakemod_dict(main_mod,ns) return main_mod def cache_main_mod(self,ns,fname): """Cache a main module's namespace. When scripts are executed via %run, we must keep a reference to the namespace of their __main__ module (a FakeModule instance) around so that Python doesn't clear it, rendering objects defined therein useless. This method keeps said reference in a private dict, keyed by the absolute path of the module object (which corresponds to the script path). 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. Note: we can not allow the actual FakeModule instances to be deleted, because of how Python tears down modules (it hard-sets all their references to None without regard for reference counts). This method must therefore make a *copy* of the given namespace, to allow the original module's __dict__ to be cleared and reused. Parameters ---------- ns : a namespace (a dict, typically) fname : str Filename associated with the namespace. Examples -------- In [10]: import IPython In [11]: _ip.cache_main_mod(IPython.__dict__,IPython.__file__) In [12]: IPython.__file__ in _ip._main_ns_cache Out[12]: True """ self._main_ns_cache[os.path.abspath(fname)] = ns.copy() 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]: _ip.cache_main_mod(IPython.__dict__,IPython.__file__) In [17]: len(_ip._main_ns_cache) > 0 Out[17]: True In [18]: _ip.clear_main_mod_cache() In [19]: len(_ip._main_ns_cache) == 0 Out[19]: True """ self._main_ns_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 pydb/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 # use pydb if available if debugger.has_pydb: from pydb import pm else: # fallback to our internal debugger pm = lambda : self.InteractiveTB.debugger(force=True) with self.readline_no_record: pm() #------------------------------------------------------------------------- # 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 # Datum: Freitag 01 Oktober 2004 04:45:34 nachmittags/abends # Gruppen: comp.lang.python # Michael Hohn wrote: # > >>> print type(builtin_check.get_global_binding('__builtins__')) # > # > >>> print type(__builtins__) # > # > 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 = set() # 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 docetst 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_ns_cache = {} # And this is the single instance of FakeModule whose __dict__ we keep # copying and clearing for reuse on each %run self._user_main_module = FakeModule() # 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__") class DummyMod(object): "A dummy module used for IPython's interactive namespace." pass 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 therm. """ # 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 theye 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 = dict() # Put 'help' in the user namespace try: from site import _Helper ns['help'] = _Helper() except ImportError: warn('help() not available - check site.py') # 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 ns['_sh'] = shadowns # 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 # 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_main_module.__dict__] + self._main_ns_cache.values() def reset(self, new_session=True): """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 self.history_manager.reset(new_session) # Reset counter used to index all histories if new_session: self.execution_count = 1 # 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() # Restore the default and user aliases self.alias_manager.clear_aliases() self.alias_manager.init_aliases() # Flush the private list of module references kept for script # execution protection self.clear_main_mod_cache() # Clear out the namespace from the last %run self.new_main_mod() 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: raise NameError("name '%s' is not defined" % varname) # Also check in output history ns_refs.append(self.history_manager.output_hist) for ns in ns_refs: to_delete = [n for n, o in ns.iteritems() if o is obj] for name in to_delete: del ns[name] # 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: raise TypeError('regex must be a string or compiled pattern') # 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, (basestring, list, tuple)): if isinstance(variables, basestring): 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: user_ns_hidden.difference_update(vdict) 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.iteritems(): if name in self.user_ns and self.user_ns[name] is obj: del self.user_ns[name] self.user_ns_hidden.discard(name) #------------------------------------------------------------------------- # Things related to object introspection #------------------------------------------------------------------------- def _ofind(self, oname, namespaces=None): """Find an object in the available namespaces. self._ofind(oname) -> dict with keys: found,obj,ospace,ismagic Has special code to detect magic functions. """ oname = oname.strip() #print '1- oname: <%r>' % oname # dbg if not oname.startswith(ESC_MAGIC) and \ not oname.startswith(ESC_MAGIC2) and \ not py3compat.isidentifier(oname, dotted=True): return dict(found=False) alias_ns = 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__), ('Alias', self.alias_manager.alias_table), ] alias_ns = self.alias_manager.alias_table # initialize results to 'null' found = False; obj = None; ospace = None; ds = None; ismagic = False; isalias = False; parent = None # We need to special-case 'print', which as of python2.6 registers as a # function but should only be treated as one if print_function was # loaded with a future import. In this case, just bail. if (oname == 'print' and not py3compat.PY3 and not \ (self.compile.compiler_flags & __future__.CO_FUTURE_PRINT_FUNCTION)): return {'found':found, 'obj':obj, 'namespace':ospace, 'ismagic':ismagic, 'isalias':isalias, 'parent':parent} # 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 = oname.split('.') oname_head, oname_rest = oname_parts[0],oname_parts[1:] for nsname,ns in namespaces: try: obj = ns[oname_head] except KeyError: continue else: #print 'oname_rest:', oname_rest # dbg for part in oname_rest: try: parent = obj 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 if ns == alias_ns: isalias = True 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 # Last try: special-case some literals like '', [], {}, etc: if not found and oname_head in ["''",'""','[]','{}','()']: obj = eval(oname_head) found = True ospace = 'Interactive' return {'found':found, 'obj':obj, 'namespace':ospace, 'ismagic':ismagic, 'isalias':isalias, 'parent':parent} def _ofind_property(self, oname, info): """Second part of object finding, to look for property details.""" if info.found: # Get the docstring of the class property if it exists. path = oname.split('.') root = '.'.join(path[:-1]) if info.parent is not None: try: target = getattr(info.parent, '__class__') # The object belongs to a class instance. try: target = getattr(target, path[-1]) # The class defines the object. if isinstance(target, property): oname = root + '.__class__.' + path[-1] info = Struct(self._ofind(oname)) except AttributeError: pass except AttributeError: pass # We return either the new info or the unmodified input if the object # hadn't been found return info def _object_find(self, oname, namespaces=None): """Find an object and return a struct with info about it.""" inf = Struct(self._ofind(oname, namespaces)) return Struct(self._ofind_property(oname, inf)) def _inspect(self, meth, oname, namespaces=None, **kw): """Generic interface to the inspector system. This function is meant to be called by pdef, pdoc & friends.""" info = self._object_find(oname, namespaces) if info.found: pmethod = getattr(self.inspector, meth) formatter = format_screen if info.ismagic else None if meth == 'pdoc': pmethod(info.obj, oname, formatter) elif meth == 'pinfo': pmethod(info.obj, oname, formatter, info, **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): 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) #------------------------------------------------------------------------- # Things related to history management #------------------------------------------------------------------------- def init_history(self): """Sets up the command history, and starts regular autosaves.""" self.history_manager = HistoryManager(shell=self, config=self.config) self.configurables.append(self.history_manager) #------------------------------------------------------------------------- # Things related to exception handling and tracebacks (not debugging) #------------------------------------------------------------------------- def init_traceback_handlers(self, custom_exceptions): # Syntax error handler. self.SyntaxTB = ultratb.SyntaxTB(color_scheme='NoColor') # 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'] self.InteractiveTB = ultratb.AutoFormattedTB(mode = 'Plain', color_scheme='NoColor', tb_offset = 1, check_cache=check_linecache_ipython) # 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. 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.""" assert type(exc_tuple)==type(()) , \ "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) #print 'Source code :','\n'.join(self.buffer) 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, basestring): 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, basestring): 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=io.stderr) # show the exception in handler first stb = self.InteractiveTB.structured_traceback(*sys.exc_info()) print(self.InteractiveTB.stb2text(stb), file=io.stdout) print("The original exception:", file=io.stdout) 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 excepts 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 showtraceback(self,exc_tuple = None,filename=None,tb_offset=None, exception_only=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: self.write_err('No traceback available to show.\n') 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) elif etype is UsageError: self.write_err("UsageError: %s" % 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: 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. stb = value._render_traceback_() except Exception: stb = self.InteractiveTB.structured_traceback(etype, value, tb, tb_offset=tb_offset) 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: self.write_err("\nKeyboardInterrupt\n") def _showtraceback(self, etype, evalue, stb): """Actually show a traceback. Subclasses may override this method to put the traceback on a different place, like a side channel. """ print(self.InteractiveTB.stb2text(stb), file=io.stdout) def showsyntaxerror(self, filename=None): """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 "" when reading from a string). """ 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 stb = self.SyntaxTB.structured_traceback(etype, value, []) 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() #------------------------------------------------------------------------- # Things related to readline #------------------------------------------------------------------------- def init_readline(self): """Command history completion/saving/reloading.""" if self.readline_use: import IPython.utils.rlineimpl as readline self.rl_next_input = None self.rl_do_indent = False if not self.readline_use or not readline.have_readline: self.has_readline = False self.readline = None # Set a number of methods that depend on readline to be no-op self.readline_no_record = no_op_context self.set_readline_completer = no_op self.set_custom_completer = no_op if self.readline_use: warn('Readline services not available or not loaded.') else: self.has_readline = True self.readline = readline sys.modules['readline'] = readline # Platform-specific configuration if os.name == 'nt': # FIXME - check with Frederick to see if we can harmonize # naming conventions with pyreadline to avoid this # platform-dependent check self.readline_startup_hook = readline.set_pre_input_hook else: self.readline_startup_hook = readline.set_startup_hook # Load user's initrc file (readline config) # Or if libedit is used, load editrc. inputrc_name = os.environ.get('INPUTRC') if inputrc_name is None: inputrc_name = '.inputrc' if readline.uses_libedit: inputrc_name = '.editrc' inputrc_name = os.path.join(self.home_dir, inputrc_name) if os.path.isfile(inputrc_name): try: readline.read_init_file(inputrc_name) except: warn('Problems reading readline initialization file <%s>' % inputrc_name) # Configure readline according to user's prefs # This is only done if GNU readline is being used. If libedit # is being used (as on Leopard) the readline config is # not run as the syntax for libedit is different. if not readline.uses_libedit: for rlcommand in self.readline_parse_and_bind: #print "loading rl:",rlcommand # dbg readline.parse_and_bind(rlcommand) # Remove some chars from the delimiters list. If we encounter # unicode chars, discard them. delims = readline.get_completer_delims() if not py3compat.PY3: delims = delims.encode("ascii", "ignore") for d in self.readline_remove_delims: delims = delims.replace(d, "") delims = delims.replace(ESC_MAGIC, '') readline.set_completer_delims(delims) # Store these so we can restore them if something like rpy2 modifies # them. self.readline_delims = delims # otherwise we end up with a monster history after a while: readline.set_history_length(self.history_length) self.refill_readline_hist() self.readline_no_record = ReadlineNoRecord(self) # Configure auto-indent for all platforms self.set_autoindent(self.autoindent) def refill_readline_hist(self): # Load the last 1000 lines from history self.readline.clear_history() stdin_encoding = sys.stdin.encoding or "utf-8" last_cell = u"" for _, _, cell in self.history_manager.get_tail(1000, include_latest=True): # Ignore blank lines and consecutive duplicates cell = cell.rstrip() if cell and (cell != last_cell): if self.multiline_history: self.readline.add_history(py3compat.unicode_to_str(cell, stdin_encoding)) else: for line in cell.splitlines(): self.readline.add_history(py3compat.unicode_to_str(line, stdin_encoding)) last_cell = cell @skip_doctest def set_next_input(self, s): """ Sets the 'default' input string for the next command line. Requires readline. Example:: In [1]: _ip.set_next_input("Hello Word") In [2]: Hello Word_ # cursor is here """ self.rl_next_input = py3compat.cast_bytes_py2(s) # Maybe move this to the terminal subclass? def pre_readline(self): """readline hook to be used at the start of each line. Currently it handles auto-indent only.""" if self.rl_do_indent: self.readline.insert_text(self._indent_current_str()) if self.rl_next_input is not None: self.readline.insert_text(self.rl_next_input) self.rl_next_input = None def _indent_current_str(self): """return the current level of indentation as a string""" return self.input_splitter.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), programatically (such as in test suites) or out-of-prcess (typically over the network by remote frontends). """ from IPython.core.completer import IPCompleter from IPython.core.completerlib import (module_completer, magic_run_completer, cd_completer, reset_completer) self.Completer = IPCompleter(shell=self, namespace=self.user_ns, global_namespace=self.user_global_ns, alias_table=self.alias_manager.alias_table, use_readline=self.has_readline, config=self.config, ) 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', 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') # Only configure readline if we truly are using readline. IPython can # do tab-completion over the network, in GUIs, etc, where readline # itself may be absent if self.has_readline: self.set_readline_completer() 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. 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. Simple usage example: 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): """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.""" newcomp = types.MethodType(completer,self.Completer) self.Completer.matchers.insert(pos,newcomp) def set_readline_completer(self): """Reset readline's completer to be our own.""" self.readline.set_completer(self.Completer.rlcomplete) 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, confg=self.config, 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_magic_function = self.magics_manager.register_function self.define_magic = self.magics_manager.define_magic self.register_magics(m.AutoMagics, m.BasicMagics, m.CodeMagics, m.ConfigMagics, m.DeprecatedMagics, m.DisplayMagics, m.ExecutionMagics, m.ExtensionMagics, m.HistoryMagics, m.LoggingMagics, m.NamespaceMagics, m.OSMagics, m.PylabMagics, m.ScriptMagics, ) # Register Magic Aliases mman = self.magics_manager mman.register_alias('ed', 'edit') mman.register_alias('hist', 'history') mman.register_alias('rep', 'recall') # 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.magic('colors %s' % self.colors) def run_line_magic(self, magic_name, line): """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. """ 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 ) error(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. stack_depth = 2 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'] = sys._getframe(stack_depth).f_locals with self.builtin_trap: result = fn(*args,**kwargs) return result 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_cell_magic(magic_name) if fn is None: lm = self.find_line_magic(magic_name) etpl = "Cell magic function `%%{0}` not found{1}." extra = '' if lm is None else (' (But line magic `%{0}` exists, ' 'did you mean that instead?)'.format(magic_name)) error(etpl.format(magic_name, extra)) elif cell == '': raise UsageError('%%{0} (with double %) expects code beneath it. ' 'Did you mean %{0} (single %)?'.format(magic_name)) 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 magic_arg_s = self.var_expand(line, stack_depth) with self.builtin_trap: result = fn(magic_arg_s, cell) 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. Use run_line_magic() instead. 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. """ # 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) #------------------------------------------------------------------------- # 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, basestring): 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 Parameters ---------- cmd : str Command to execute. """ cmd = self.var_expand(cmd, depth=1) # 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) cmd = py3compat.unicode_to_str(cmd) ec = os.system(cmd) else: cmd = py3compat.unicode_to_str(cmd) ec = os.system(cmd) # The high byte is the exit code, the low byte is a signal number # that we discard for now. See the docs for os.wait() if ec > 255: ec >>= 8 # 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'] = 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, config=self.config) self.configurables.append(self.alias_manager) self.ns_table['alias'] = self.alias_manager.alias_table, #------------------------------------------------------------------------- # Things related to extensions #------------------------------------------------------------------------- def init_extension_manager(self): self.extension_manager = ExtensionManager(shell=self, config=self.config) self.configurables.append(self.extension_manager) #------------------------------------------------------------------------- # Things related to payloads #------------------------------------------------------------------------- def init_payload(self): self.payload_manager = PayloadManager(config=self.config) self.configurables.append(self.payload_manager) #------------------------------------------------------------------------- # Things related to the prefilter #------------------------------------------------------------------------- def init_prefilter(self): self.prefilter_manager = PrefilterManager(shell=self, config=self.config) 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 rw = self.prompt_manager.render('rewrite') + cmd try: # plain ascii works better w/ pyreadline, on some machines, so # we use it and only print uncolored rewrite if we have unicode rw = str(rw) print(rw, file=io.stdout) except UnicodeEncodeError: print("------> " + cmd) #------------------------------------------------------------------------- # Things related to extracting values/expressions from kernel and user_ns #------------------------------------------------------------------------- def _simple_error(self): etype, value = sys.exc_info()[:2] return u'[ERROR] {e.__name__}: {v}'.format(e=etype, v=value) def user_variables(self, names): """Get a list of variable names from the user's namespace. Parameters ---------- names : list of strings A list of names of variables to be read from the user namespace. Returns ------- A dict, keyed by the input names and with the repr() of each value. """ out = {} user_ns = self.user_ns for varname in names: try: value = repr(user_ns[varname]) except: value = self._simple_error() out[varname] = value return out 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 repr() of each value. """ out = {} user_ns = self.user_ns global_ns = self.user_global_ns for key, expr in expressions.iteritems(): try: value = repr(eval(expr, global_ns, user_ns)) except: value = self._simple_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 in 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, **kw): """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. """ kw.setdefault('exit_ignore', False) kw.setdefault('raise_exceptions', False) fname = os.path.abspath(os.path.expanduser(fname)) # Make sure we can open the file try: with open(fname) as thefile: 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 = os.path.dirname(fname) with prepended_to_syspath(dname): try: py3compat.execfile(fname,*where) 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 kw['raise_exceptions']: raise if status.code not in (0, None) and not kw['exit_ignore']: self.showtraceback(exception_only=True) except: if kw['raise_exceptions']: raise self.showtraceback() def safe_execfile_ipy(self, fname): """Like safe_execfile, but for .ipy files with IPython syntax. Parameters ---------- fname : str The name of the file to execute. The filename must have a .ipy extension. """ fname = os.path.abspath(os.path.expanduser(fname)) # Make sure we can open the file try: with open(fname) as thefile: 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 = os.path.dirname(fname) with prepended_to_syspath(dname): try: with open(fname) as thefile: # self.run_cell currently captures all exceptions # raised in user code. It would be nice if there were # versions of runlines, execfile that did raise, so # we could catch the errors. self.run_cell(thefile.read(), store_history=False, shell_futures=False) except: 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. Parameters ---------- mod_name : string The name of the module to be executed. where : dict The globals namespace. """ try: where.update( runpy.run_module(str(mod_name), run_name="__main__", alter_sys=True) ) except: self.showtraceback() warn('Unknown failure executing module: <%s>' % mod_name) def _run_cached_cell_magic(self, magic_name, line): """Special method to call a cell magic with the data stored in self. """ cell = self._current_cell_magic_body self._current_cell_magic_body = None return self.run_cell_magic(magic_name, line, cell) def run_cell(self, raw_cell, store_history=False, silent=False, shell_futures=True): """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. """ if (not raw_cell) or raw_cell.isspace(): return if silent: store_history = False self.input_splitter.push(raw_cell) # Check for cell magics, which leave state behind. This interface is # ugly, we need to do something cleaner later... Now the logic is # simply that the input_splitter remembers if there was a cell magic, # and in that case we grab the cell body. if self.input_splitter.cell_magic_parts: self._current_cell_magic_body = \ ''.join(self.input_splitter.cell_magic_parts) cell = self.input_splitter.source_reset() # 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 CachingCompiler() with self.builtin_trap: prefilter_failed = False if len(cell.splitlines()) == 1: try: # use prefilter_lines to handle trailing newlines # restore trailing newline for ast.parse cell = self.prefilter_manager.prefilter_lines(cell) + '\n' except AliasError as e: error(e) prefilter_failed = True except Exception: # don't allow prefilter errors to crash IPython self.showtraceback() prefilter_failed = True # Store raw and processed history if store_history: self.history_manager.store_inputs(self.execution_count, cell, raw_cell) if not silent: self.logger.log(cell, raw_cell) if not prefilter_failed: # don't run if prefilter failed cell_name = self.compile.cache(cell, self.execution_count) with self.display_trap: try: code_ast = compiler.ast_parse(cell, filename=cell_name) except IndentationError: self.showindentationerror() if store_history: self.execution_count += 1 return None except (OverflowError, SyntaxError, ValueError, TypeError, MemoryError): self.showsyntaxerror() if store_history: self.execution_count += 1 return None code_ast = self.transform_ast(code_ast) interactivity = "none" if silent else self.ast_node_interactivity self.run_ast_nodes(code_ast.body, cell_name, interactivity=interactivity, compiler=compiler) # Execute any registered post-execution functions. # unless we are silent post_exec = [] if silent else self._post_execute.iteritems() for func, status in post_exec: if self.disable_failing_post_execute and not status: continue try: func() except KeyboardInterrupt: print("\nKeyboardInterrupt", file=io.stderr) except Exception: # register as failing: self._post_execute[func] = False self.showtraceback() print('\n'.join([ "post-execution function %r produced an error." % func, "If this problem persists, you can disable failing post-exec functions with:", "", " get_ipython().disable_failing_post_execute = True" ]), file=io.stderr) 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 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 Exception: warn("AST transformer %r threw an error. It will be unregistered." % transformer) self.ast_transformers.remove(transformer) if self.ast_transformers: ast.fix_missing_locations(node) return node def run_ast_nodes(self, nodelist, cell_name, interactivity='last_expr', compiler=compile): """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' 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. 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(). """ if not nodelist: return 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) exec_count = self.execution_count try: for i, node in enumerate(to_run_exec): mod = ast.Module([node]) code = compiler(mod, cell_name, "exec") if self.run_code(code): return True for i, node in enumerate(to_run_interactive): mod = ast.Interactive([node]) code = compiler(mod, cell_name, "single") if self.run_code(code): 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. self.showtraceback() return False def run_code(self, code_obj): """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 Returns ------- False : successful execution. True : an error occurred. """ # 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 = 1 # happens in more places, so it's easier as default try: try: self.hooks.pre_run_code_hook() #rprint('Running code', repr(code_obj)) # dbg exec code_obj in self.user_global_ns, self.user_ns finally: # Reset our crash handler in place sys.excepthook = old_excepthook except SystemExit: self.showtraceback(exception_only=True) warn("To exit: use 'exit', 'quit', or Ctrl-D.", level=1) except self.custom_exceptions: etype,value,tb = sys.exc_info() self.CustomTB(etype,value,tb) except: self.showtraceback() else: outflag = 0 return outflag # For backwards compatibility runcode = run_code #------------------------------------------------------------------------- # Things related to GUI support and pylab #------------------------------------------------------------------------- def enable_gui(self, gui=None): raise NotImplementedError('Implement enable_gui in a subclass') 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. 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 IPython.core.pylabtools import mpl_runner # 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 = {} try: gui = pylab_activate(ns, gui, import_all, self, welcome_message=welcome_message) except KeyError: error("Backend %r not supported" % gui) return self.user_ns.update(ns) self.user_ns_hidden.update(ns) # 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 = \ mpl_runner(self.safe_execfile) #------------------------------------------------------------------------- # 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() ns.update(sys._getframe(depth+1).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.mktemp, 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.""" filename = tempfile.mktemp('.py', prefix) self.tempfiles.append(filename) if data: tmp_file = open(filename,'w') tmp_file.write(data) tmp_file.close() return filename # TODO: This should be removed when Term is refactored. def write(self,data): """Write a string to the default output""" io.stdout.write(data) # TODO: This should be removed when Term is refactored. def write_err(self,data): """Write a string to the default error output""" io.stderr.write(data) def ask_yes_no(self, prompt, default=None): if self.quiet: return True return ask_yes_no(prompt,default) 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 : string 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. Optional Parameters: - raw(False): by default, the processed input is used. If this is true, the raw input history is used instead. Note that slices can be called 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) return "\n".join(x for _, _, x in lines) def find_user_code(self, target, raw=True, py_only=False, skip_encoding_cookie=True): """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, correspnding .py file, filename, or an expression evaluating to a string or Macro in the user namespace. 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 utarget = unquote_filename(target) try: if utarget.startswith(('http://', 'https://')): return openpy.read_py_url(utarget, skip_encoding_cookie=skip_encoding_cookie) except UnicodeDecodeError: if not py_only : from urllib import urlopen # Deferred import response = urlopen(target) return response.read().decode('latin1') raise ValueError(("'%s' seem to be unreadable.") % utarget) 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 : if not py_only : with io_open(tgt,'r', encoding='latin1') as f : return f.read() raise ValueError(("'%s' seem to be unreadable.") % target) try: # User namespace codeobj = eval(target, self.user_ns) except Exception: raise ValueError(("'%s' was not found in history, as a file, url, " "nor in the user namespace.") % target) if isinstance(codeobj, basestring): return codeobj elif isinstance(codeobj, Macro): return codeobj.value raise TypeError("%s is neither a string nor a macro." % target, codeobj) #------------------------------------------------------------------------- # 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 """ # 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() # Cleanup all tempfiles left around for tfile in self.tempfiles: try: os.unlink(tfile) except OSError: pass # Clear all user namespaces to release all references cleanly. self.reset(new_session=False) # Run user hooks self.hooks.shutdown_hook() def cleanup(self): self.restore_sys_module_state() class InteractiveShellABC(object): """An abstract base class for InteractiveShell.""" __metaclass__ = abc.ABCMeta InteractiveShellABC.register(InteractiveShell)