Merge pull request #5188 from takluyver/callbacks

New events system

IPython/core/events.py

@@ -0,0 +1,139 b''
+"""Infrastructure for registering and firing callbacks on application events.
+
+Unlike :mod:`IPython.core.hooks`, which lets end users set single functions to
+be called at specific times, or a collection of alternative methods to try,
+callbacks are designed to be used by extension authors. A number of callbacks
+can be registered for the same event without needing to be aware of one another.
+
+The functions defined in this module are no-ops indicating the names of available
+events and the arguments which will be passed to them.
+
+.. note::
+
+   This API is experimental in IPython 2.0, and may be revised in future versions.
+"""
+from __future__ import print_function
+
+class EventManager(object):
+    """Manage a collection of events and a sequence of callbacks for each.
+    
+    This is attached to :class:`~IPython.core.interactiveshell.InteractiveShell`
+    instances as an ``events`` attribute.
+    
+    .. note::
+
+       This API is experimental in IPython 2.0, and may be revised in future versions.
+    """
+    def __init__(self, shell, available_events):
+        """Initialise the :class:`CallbackManager`.
+        
+        Parameters
+        ----------
+        shell
+          The :class:`~IPython.core.interactiveshell.InteractiveShell` instance
+        available_callbacks
+          An iterable of names for callback events.
+        """
+        self.shell = shell
+        self.callbacks = {n:[] for n in available_events}
+    
+    def register(self, event, function):
+        """Register a new event callback
+        
+        Parameters
+        ----------
+        event : str
+          The event for which to register this callback.
+        function : callable
+          A function to be called on the given event. It should take the same
+          parameters as the appropriate callback prototype.
+        
+        Raises
+        ------
+        TypeError
+          If ``function`` is not callable.
+        KeyError
+          If ``event`` is not one of the known events.
+        """
+        if not callable(function):
+            raise TypeError('Need a callable, got %r' % function)
+        self.callbacks[event].append(function)
+    
+    def unregister(self, event, function):
+        """Remove a callback from the given event."""
+        self.callbacks[event].remove(function)
+    
+    def reset(self, event):
+        """Clear all callbacks for the given event."""
+        self.callbacks[event] = []
+    
+    def reset_all(self):
+        """Clear all callbacks for all events."""
+        self.callbacks = {n:[] for n in self.callbacks}
+    
+    def trigger(self, event, *args, **kwargs):
+        """Call callbacks for ``event``.
+        
+        Any additional arguments are passed to all callbacks registered for this
+        event. Exceptions raised by callbacks are caught, and a message printed.
+        """
+        for func in self.callbacks[event]:
+            try:
+                func(*args, **kwargs)
+            except Exception:
+                print("Error in callback {} (for {}):".format(func, event))
+                self.shell.showtraceback()
+
+# event_name -> prototype mapping
+available_events = {}
+
+def _define_event(callback_proto):
+    available_events[callback_proto.__name__] = callback_proto
+    return callback_proto
+
+# ------------------------------------------------------------------------------
+# Callback prototypes
+#
+# No-op functions which describe the names of available events and the
+# signatures of callbacks for those events.
+# ------------------------------------------------------------------------------
+
+@_define_event
+def pre_execute():
+    """Fires before code is executed in response to user/frontend action.
+    
+    This includes comm and widget messages and silent execution, as well as user
+    code cells."""
+    pass
+
+@_define_event
+def pre_run_cell():
+    """Fires before user-entered code runs."""
+    pass
+
+@_define_event
+def post_execute():
+    """Fires after code is executed in response to user/frontend action.
+    
+    This includes comm and widget messages and silent execution, as well as user
+    code cells."""
+    pass
+
+@_define_event
+def post_run_cell():
+    """Fires after user-entered code runs."""
+    pass
+
+@_define_event
+def shell_initialized(ip):
+    """Fires after initialisation of :class:`~IPython.core.interactiveshell.InteractiveShell`.
+    
+    This is before extensions and startup scripts are loaded, so it can only be
+    set by subclassing.
+    
+    Parameters
+    ----------
+    ip : :class:`~IPython.core.interactiveshell.InteractiveShell`
+      The newly initialised shell.
+    """
+    pass

IPython/core/tests/test_events.py

@@ -0,0 +1,46 b''
+import unittest
+try:  # Python 3.3 +
+    from unittest.mock import Mock
+except ImportError:
+    from mock import Mock
+
+from IPython.core import events
+import IPython.testing.tools as tt
+
+def ping_received():
+    pass
+
+class CallbackTests(unittest.TestCase):
+    def setUp(self):
+        self.em = events.EventManager(get_ipython(), {'ping_received': ping_received})
+    
+    def test_register_unregister(self):
+        cb = Mock()
+
+        self.em.register('ping_received', cb)        
+        self.em.trigger('ping_received')
+        self.assertEqual(cb.call_count, 1)
+        
+        self.em.unregister('ping_received', cb)
+        self.em.trigger('ping_received')
+        self.assertEqual(cb.call_count, 1)
+    
+    def test_reset(self):
+        cb = Mock()
+        self.em.register('ping_received', cb)
+        self.em.reset('ping_received')
+        self.em.trigger('ping_received')
+        assert not cb.called
+    
+    def test_reset_all(self):
+        cb = Mock()
+        self.em.register('ping_received', cb)
+        self.em.reset_all()
+        self.em.trigger('ping_received')
+        assert not cb.called
+    
+    def test_cb_error(self):
+        cb = Mock(side_effect=ValueError)
+        self.em.register('ping_received', cb)
+        with tt.AssertPrints("Error in callback"):
+            self.em.trigger('ping_received')
  No newline at end of file

docs/source/config/callbacks.rst

@@ -0,0 +1,42 b''
+=====================
+Registering callbacks
+=====================
+
+Extension code can register callbacks functions which will be called on specific
+events within the IPython code. You can see the current list of available
+callbacks, and the parameters that will be passed with each, in the callback
+prototype functions defined in :mod:`IPython.core.callbacks`.
+
+To register callbacks, use :meth:`IPython.core.events.EventManager.register`.
+For example::
+
+    class VarWatcher(object):
+        def __init__(self, ip):
+            self.shell = ip
+            self.last_x = None
+        
+        def pre_execute(self):
+            self.last_x = self.shell.user_ns.get('x', None)
+        
+        def post_execute(self):
+            if self.shell.user_ns.get('x', None) != self.last_x:
+                print("x changed!")
+
+    def load_ipython_extension(ip):
+        vw = VarWatcher(ip)
+        ip.events.register('pre_execute', vw.pre_execute)
+        ip.events.register('post_execute', vw.post_execute)
+
+.. note::
+
+   This API is experimental in IPython 2.0, and may be revised in future versions.
+
+.. seealso::
+
+   Module :mod:`IPython.core.hooks`
+     The older 'hooks' system allows end users to customise some parts of
+     IPython's behaviour.
+   
+   :doc:`inputtransforms`
+     By registering input transformers that don't change code, you can monitor
+     what is being executed.

docs/source/whatsnew/pr/callbacks.rst

@@ -0,0 +1,1 b''
+* A new callback system has been introduced. For details, see :doc:`/config/callbacks`.

.travis.yml

@@ -1,18 +1,18 b''
 # http://travis-ci.org/#!/ipython/ipython
 language: python
 python:
     - 2.7
     - 3.3
 before_install:
     # workaround for https://github.com/travis-ci/travis-cookbooks/issues/155
     - sudo rm -rf /dev/shm && sudo ln -s /run/shm /dev/shm
     - easy_install -q pyzmq
-    - pip install jinja2 sphinx pygments tornado requests
+    - pip install jinja2 sphinx pygments tornado requests mock
     # Pierre Carrier's PPA for PhantomJS and CasperJS
     - sudo add-apt-repository -y ppa:pcarrier/ppa
     - sudo apt-get update
     - sudo apt-get install pandoc casperjs nodejs
 install:
     - python setup.py install -q 
 script:
     - cd /tmp && iptest

IPython/core/hooks.py

@@ -1,209 +1,214 b''
 """Hooks for IPython.
 
 In Python, it is possible to overwrite any method of any object if you really
 want to.  But IPython exposes a few 'hooks', methods which are *designed* to
 be overwritten by users for customization purposes.  This module defines the
 default versions of all such hooks, which get used by IPython if not
 overridden by the user.
 
 Hooks are simple functions, but they should be declared with ``self`` as their
 first argument, because when activated they are registered into IPython as
 instance methods. The self argument will be the IPython running instance
 itself, so hooks have full access to the entire IPython object.
 
 If you wish to define a new hook and activate it, you can make an :doc:`extension
 </config/extensions/index>` or a :ref:`startup script <startup_files>`. For
 example, you could use a startup file like this::
 
     import os
 
     def calljed(self,filename, linenum):
         "My editor hook calls the jed editor directly."
         print "Calling my own editor, jed ..."
         if os.system('jed +%d %s' % (linenum,filename)) != 0:
             raise TryNext()
 
     def load_ipython_extension(ip):
         ip.set_hook('editor', calljed)
 
 """
 
 #*****************************************************************************
 #       Copyright (C) 2005 Fernando Perez. <[e-mail]>
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #*****************************************************************************
 
 import os
 import subprocess
 import sys
 
 from IPython.core.error import TryNext
 
 # List here all the default hooks.  For now it's just the editor functions
 # but over time we'll move here all the public API for user-accessible things.
 
 __all__ = ['editor', 'fix_error_editor', 'synchronize_with_editor',
            'shutdown_hook', 'late_startup_hook',
            'show_in_pager','pre_prompt_hook',
            'pre_run_code_hook', 'clipboard_get']
 
+deprecated = {'pre_run_code_hook': "a callback for the 'pre_execute' or 'pre_run_cell' event",
+              'late_startup_hook': "a callback for the 'shell_initialized' event",
+              'shutdown_hook': "the atexit module",
+             }
+
 def editor(self, filename, linenum=None, wait=True):
     """Open the default editor at the given filename and linenumber.
 
     This is IPython's default editor hook, you can use it as an example to
     write your own modified one.  To set your own editor function as the
     new editor hook, call ip.set_hook('editor',yourfunc)."""
 
     # IPython configures a default editor at startup by reading $EDITOR from
     # the environment, and falling back on vi (unix) or notepad (win32).
     editor = self.editor
 
     # marker for at which line to open the file (for existing objects)
     if linenum is None or editor=='notepad':
         linemark = ''
     else:
         linemark = '+%d' % int(linenum)
 
     # Enclose in quotes if necessary and legal
     if ' ' in editor and os.path.isfile(editor) and editor[0] != '"':
         editor = '"%s"' % editor
 
     # Call the actual editor
     proc = subprocess.Popen('%s %s %s' % (editor, linemark, filename),
                             shell=True)
     if wait and proc.wait() != 0:
         raise TryNext()
 
 import tempfile
 def fix_error_editor(self,filename,linenum,column,msg):
     """Open the editor at the given filename, linenumber, column and
     show an error message. This is used for correcting syntax errors.
     The current implementation only has special support for the VIM editor,
     and falls back on the 'editor' hook if VIM is not used.
 
     Call ip.set_hook('fix_error_editor',youfunc) to use your own function,
     """
     def vim_quickfix_file():
         t = tempfile.NamedTemporaryFile()
         t.write('%s:%d:%d:%s\n' % (filename,linenum,column,msg))
         t.flush()
         return t
     if os.path.basename(self.editor) != 'vim':
         self.hooks.editor(filename,linenum)
         return
     t = vim_quickfix_file()
     try:
         if os.system('vim --cmd "set errorformat=%f:%l:%c:%m" -q ' + t.name):
             raise TryNext()
     finally:
         t.close()
 
 
 def synchronize_with_editor(self, filename, linenum, column):
         pass
 
 
 class CommandChainDispatcher:
     """ Dispatch calls to a chain of commands until some func can handle it
 
     Usage: instantiate, execute "add" to add commands (with optional
     priority), execute normally via f() calling mechanism.
 
     """
     def __init__(self,commands=None):
         if commands is None:
             self.chain = []
         else:
             self.chain = commands
 
 
     def __call__(self,*args, **kw):
         """ Command chain is called just like normal func.
 
         This will call all funcs in chain with the same args as were given to
         this function, and return the result of first func that didn't raise
         TryNext"""
         last_exc = TryNext()
         for prio,cmd in self.chain:
             #print "prio",prio,"cmd",cmd #dbg
             try:
                 return cmd(*args, **kw)
             except TryNext as exc:
                 last_exc = exc
         # if no function will accept it, raise TryNext up to the caller
         raise last_exc
 
     def __str__(self):
         return str(self.chain)
 
     def add(self, func, priority=0):
         """ Add a func to the cmd chain with given priority """
         self.chain.append((priority, func))
         self.chain.sort(key=lambda x: x[0])
 
     def __iter__(self):
         """ Return all objects in chain.
 
         Handy if the objects are not callable.
         """
         return iter(self.chain)
 
 
 def shutdown_hook(self):
     """ default shutdown hook
 
     Typically, shotdown hooks should raise TryNext so all shutdown ops are done
     """
 
     #print "default shutdown hook ok" # dbg
     return
 
 
 def late_startup_hook(self):
     """ Executed after ipython has been constructed and configured
 
     """
     #print "default startup hook ok" # dbg
 
 
 def show_in_pager(self,s):
     """ Run a string through pager """
     # raising TryNext here will use the default paging functionality
     raise TryNext
 
 
 def pre_prompt_hook(self):
     """ Run before displaying the next prompt
 
     Use this e.g. to display output from asynchronous operations (in order
     to not mess up text entry)
     """
 
     return None
 
 
 def pre_run_code_hook(self):
     """ Executed before running the (prefiltered) code in IPython """
     return None
 
 
 def clipboard_get(self):
     """ Get text from the clipboard.
     """
     from IPython.lib.clipboard import (
         osx_clipboard_get, tkinter_clipboard_get,
         win32_clipboard_get
     )
     if sys.platform == 'win32':
         chain = [win32_clipboard_get, tkinter_clipboard_get]
     elif sys.platform == 'darwin':
         chain = [osx_clipboard_get, tkinter_clipboard_get]
     else:
         chain = [tkinter_clipboard_get]
     dispatcher = CommandChainDispatcher()
     for func in chain:
         dispatcher.add(func)
     text = dispatcher()
     return text

IPython/core/interactiveshell.py

@@ -1,3213 +1,3217 b''
 # -*- coding: utf-8 -*-
 """Main IPython class."""
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2001 Janko Hauser <[e-mail]>
 #  Copyright (C) 2001-2007 Fernando Perez. <[e-mail]>
 #  Copyright (C) 2008-2011  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 from __future__ import absolute_import
 from __future__ import print_function
 
 import __future__
 import abc
 import ast
 import atexit
 import functools
 import os
 import re
 import runpy
 import sys
 import tempfile
 import types
 import subprocess
 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.events import EventManager, available_events
 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.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.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.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.py3compat import (builtin_mod, unicode_type, string_types,
                                      with_metaclass, iteritems)
 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):
     r"""A Unicode subclass to validate separate_in, separate_out, etc.
 
     This is a Unicode based trait that converts '0'->'' and ``'\\n'->'\n'``.
     """
 
     def validate(self, obj, value):
         if value == '0': value = ''
         value = value.replace('\\n','\n')
         return super(SeparateUnicode, self).validate(obj, value)
 
 
 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)]
 
 
 @undoc
 class DummyMod(object):
     """A dummy module used for IPython's interactive module when
     a namespace must be assigned to the module's __dict__."""
     pass
 
 #-----------------------------------------------------------------------------
 # 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 console>")
     ipython_dir= Unicode('', config=True) # Set to get_ipython_dir() in __init__
 
     # Input splitter, to transform input line by line and detect when a block
     # is ready to be executed.
     input_splitter = Instance('IPython.core.inputsplitter.IPythonInputSplitter',
                               (), {'line_input_checker': True})
     
     # This InputSplitter instance is used to transform completed cells before
     # running them. It allows cell magics to contain blank lines.
     input_transformer_manager = Instance('IPython.core.inputsplitter.IPythonInputSplitter',
                                          (), {'line_input_checker': False})
     
     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, ipython_dir=None, profile_dir=None,
                  user_module=None, user_ns=None,
                  custom_exceptions=((), None), **kwargs):
 
         # This is where traits with a config_key argument are updated
         # from the values on config.
         super(InteractiveShell, self).__init__(**kwargs)
         self.configurables = [self]
 
         # These are relatively independent and stateless
         self.init_ipython_dir(ipython_dir)
         self.init_profile_dir(profile_dir)
         self.init_instance_attrs()
         self.init_environment()
         
         # Check if we're in a virtualenv, and set up sys.path.
         self.init_virtualenv()
 
         # Create namespaces (user_ns, user_global_ns, etc.)
         self.init_create_namespaces(user_module, user_ns)
         # This has to be done after init_create_namespaces because it uses
         # something in self.user_ns, but before init_sys_modules, which
         # is the first thing to modify sys.
         # TODO: When we override sys.stdout and sys.stderr before this class
         # is created, we are saving the overridden ones here. Not sure if this
         # is what we want to do.
         self.save_sys_module_state()
         self.init_sys_modules()
 
         # While we're trying to have each part of the code directly access what
         # it needs without keeping redundant references to objects, we have too
         # much legacy code that expects ip.db to exist.
         self.db = PickleShareDB(os.path.join(self.profile_dir.location, 'db'))
 
         self.init_history()
         self.init_encoding()
         self.init_prefilter()
 
         self.init_syntax_highlighting()
         self.init_hooks()
+        self.init_events()
         self.init_pushd_popd_magic()
         # self.init_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_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_latextool()
         self.init_magics()
         self.init_alias()
         self.init_logstart()
         self.init_pdb()
         self.init_extension_manager()
         self.init_payload()
         self.init_comms()
         self.hooks.late_startup_hook()
+        self.events.trigger('shell_initialized', self)
         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 = []
         self.tempdirs = []
 
         # 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 = py3compat.getcwd()
 
         # Indentation management
         self.indent_current_nsp = 0
 
         # Dict to track post-execution functions that have been registered
         self._post_execute = {}
 
     def init_environment(self):
         """Any changes we need to make to the user's environment."""
         pass
 
     def init_encoding(self):
         # Get system encoding at startup time.  Certain terminals (like Emacs
         # under Win32 have it set to None, and we need to have a known valid
         # encoding to use in the raw_input() method
         try:
             self.stdin_encoding = sys.stdin.encoding or 'ascii'
         except AttributeError:
             self.stdin_encoding = 'ascii'
 
     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, parent=self)
         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(parent=self)
         self.configurables.append(self.display_formatter)
 
     def init_display_pub(self):
         self.display_pub = self.display_pub_class(parent=self)
         self.configurables.append(self.display_pub)
 
     def init_data_pub(self):
         if not self.data_pub_class:
             self.data_pub = None
             return
         self.data_pub = self.data_pub_class(parent=self)
         self.configurables.append(self.data_pub)
 
     def init_displayhook(self):
         # Initialize displayhook, set in/out prompts and printing system
         self.displayhook = self.displayhook_class(
             parent=self,
             shell=self,
             cache_size=self.cache_size,
         )
         self.configurables.append(self.displayhook)
         # This is a context manager that installs/revmoes the displayhook at
         # the appropriate time.
         self.display_trap = DisplayTrap(hook=self.displayhook)
 
     def init_latextool(self):
         """Configure LaTeXTool."""
         cfg = LaTeXTool.instance(parent=self)
         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
         
         # venv detection:
         # stdlib venv may symlink sys.executable, so we can't use realpath.
         # but others can symlink *to* the venv Python, so we can't just use sys.executable.
         # So we just check every item in the symlink tree (generally <= 3)
         p = sys.executable
         paths = [p]
         while os.path.islink(p):
             p = os.path.join(os.path.dirname(p), os.readlink(p))
             paths.append(p)
         if any(p.startswith(os.environ['VIRTUAL_ENV']) for p in paths):
             # 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 iteritems(self._orig_sys_module_state):
                 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)
+            self.set_hook(hook_name,getattr(hooks,hook_name), 100, _warn_deprecated=False)
 
-    def set_hook(self,name,hook, priority = 50, str_key = None, re_key = None):
+    def set_hook(self,name,hook, priority=50, str_key=None, re_key=None,
+                 _warn_deprecated=True):
         """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 _warn_deprecated and (name in IPython.core.hooks.deprecated):
+            alternative = IPython.core.hooks.deprecated[name]
+            warn("Hook {} is deprecated. Use {} instead.".format(name, alternative))
+
         if not dp:
             dp = IPython.core.hooks.CommandChainDispatcher()
 
         try:
             dp.add(f,priority)
         except AttributeError:
             # it was not commandchain, plain old func - replace
             dp = f
 
         setattr(self.hooks,name, dp)
 
+    #-------------------------------------------------------------------------
+    # Things related to events
+    #-------------------------------------------------------------------------
+
+    def init_events(self):
+        self.events = EventManager(self, available_events)
+
     def register_post_execute(self, func):
-        """Register a function for calling after code execution.
+        """DEPRECATED: Use ip.events.register('post_run_cell', 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
+        warn("ip.register_post_execute is deprecated, use "
+             "ip.events.register('post_run_cell', func) instead.")
+        self.events.register('post_run_cell', func)
     
     #-------------------------------------------------------------------------
     # Things related to the "main" module
     #-------------------------------------------------------------------------
 
     def new_main_mod(self, filename, modname):
         """Return a new 'main' module object for user code execution.
         
         ``filename`` should be the path of the script which will be run in the
         module. Requests with the same filename will get the same module, with
         its namespace cleared.
         
         ``modname`` should be the module name - normally either '__main__' or
         the basename of the file without the extension.
         
         When scripts are executed via %run, we must keep a reference to their
         __main__ module around so that Python doesn't
         clear it, rendering references to module globals useless.
 
         This method keeps said reference in a private dict, keyed by the
         absolute path of the script. This way, for multiple executions of the
         same script we only keep one copy of the namespace (the last one),
         thus preventing memory leaks from old references while allowing the
         objects from the last execution to be accessible.
         """
         filename = os.path.abspath(filename)
         try:
             main_mod = self._main_mod_cache[filename]
         except KeyError:
             main_mod = self._main_mod_cache[filename] = types.ModuleType(modname,
                         doc="Module created for script run in IPython")
         else:
             main_mod.__dict__.clear()
             main_mod.__name__ = modname
         
         main_mod.__file__ = filename
         # It seems pydoc (and perhaps others) needs any module instance to
         # implement a __nonzero__ method
         main_mod.__nonzero__ = lambda : True
         
         return main_mod
 
     def clear_main_mod_cache(self):
         """Clear the cache of main modules.
 
         Mainly for use by utilities like %reset.
 
         Examples
         --------
 
         In [15]: import IPython
 
         In [16]: m = _ip.new_main_mod(IPython.__file__, 'IPython')
 
         In [17]: len(_ip._main_mod_cache) > 0
         Out[17]: True
 
         In [18]: _ip.clear_main_mod_cache()
 
         In [19]: len(_ip._main_mod_cache) == 0
         Out[19]: True
         """
         self._main_mod_cache.clear()
 
     #-------------------------------------------------------------------------
     # Things related to debugging
     #-------------------------------------------------------------------------
 
     def init_pdb(self):
         # Set calling of pdb on exceptions
         # self.call_pdb is a property
         self.call_pdb = self.pdb
 
     def _get_call_pdb(self):
         return self._call_pdb
 
     def _set_call_pdb(self,val):
 
         if val not in (0,1,False,True):
             raise ValueError('new call_pdb value must be boolean')
 
         # store value in instance
         self._call_pdb = val
 
         # notify the actual exception handlers
         self.InteractiveTB.call_pdb = val
 
     call_pdb = property(_get_call_pdb,_set_call_pdb,None,
                         'Control auto-activation of pdb at exceptions')
 
     def debugger(self,force=False):
         """Call the 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 <[e-mail]>
         # Datum: Freitag 01 Oktober 2004 04:45:34 nachmittags/abends
         # Gruppen: comp.lang.python
 
         # Michael Hohn <[e-mail]> wrote:
         # > >>> print type(builtin_check.get_global_binding('__builtins__'))
         # > <type 'dict'>
         # > >>> print type(__builtins__)
         # > <type 'module'>
         # > Is this difference in return value intentional?
 
         # Well, it's documented that '__builtins__' can be either a dictionary
         # or a module, and it's been that way for a long time. Whether it's
         # intentional (or sensible), I don't know. In any case, the idea is
         # that if you need to access the built-in namespace directly, you
         # should start with "import __builtin__" (note, no 's') which will
         # definitely give you a module. Yeah, it's somewhat confusing:-(.
 
         # These routines return a properly built module and dict as needed by
         # the rest of the code, and can also be used by extension writers to
         # generate properly initialized namespaces.
         if (user_ns is not None) or (user_module is not None):
             self.default_user_namespaces = False
         self.user_module, self.user_ns = self.prepare_user_module(user_module, user_ns)
 
         # A record of hidden variables we have added to the user namespace, so
         # we can list later only variables defined in actual interactive use.
         self.user_ns_hidden = {}
 
         # Now that FakeModule produces a real module, we've run into a nasty
         # problem: after script execution (via %run), the module where the user
         # code ran is deleted.  Now that this object is a true module (needed
         # so 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_mod_cache = {}
 
         # A table holding all the namespaces IPython deals with, so that
         # introspection facilities can search easily.
         self.ns_table = {'user_global':self.user_module.__dict__,
                          'user_local':self.user_ns,
                          'builtin':builtin_mod.__dict__
                          }
     
     @property
     def user_global_ns(self):
         return self.user_module.__dict__
 
     def prepare_user_module(self, user_module=None, user_ns=None):
         """Prepare the module and namespace in which user code will be run.
         
         When IPython is started normally, both parameters are None: a new module
         is created automatically, and its __dict__ used as the namespace.
         
         If only user_module is provided, its __dict__ is used as the namespace.
         If only user_ns is provided, a dummy module is created, and user_ns
         becomes the global namespace. If both are provided (as they may be
         when embedding), user_ns is the local namespace, and user_module
         provides the global namespace.
 
         Parameters
         ----------
         user_module : module, optional
             The current user module in which IPython is being run. If None,
             a clean module will be created.
         user_ns : dict, optional
             A namespace in which to run interactive commands.
 
         Returns
         -------
         A tuple of user_module and user_ns, each properly initialised.
         """
         if user_module is None and user_ns is not None:
             user_ns.setdefault("__name__", "__main__")
             user_module = DummyMod()
             user_module.__dict__ = user_ns
             
         if user_module is None:
             user_module = types.ModuleType("__main__",
                 doc="Automatically created module for IPython interactive environment")
         
         # We must ensure that __builtin__ (without the final 's') is always
         # available and pointing to the __builtin__ *module*.  For more details:
         # http://mail.python.org/pipermail/python-dev/2001-April/014068.html
         user_module.__dict__.setdefault('__builtin__', builtin_mod)
         user_module.__dict__.setdefault('__builtins__', builtin_mod)
         
         if user_ns is None:
             user_ns = user_module.__dict__
 
         return user_module, user_ns
 
     def init_sys_modules(self):
         # We need to insert into sys.modules something that looks like a
         # module but which accesses the IPython namespace, for shelve and
         # pickle to work interactively. Normally they rely on getting
         # everything out of __main__, but for embedding purposes each IPython
         # instance has its own private namespace, so we can't go shoving
         # everything into __main__.
 
         # note, however, that we should only do this for non-embedded
         # ipythons, which really mimic the __main__.__dict__ with their own
         # namespace.  Embedded instances, on the other hand, should not do
         # this because they need to manage the user local/global namespaces
         # only, but they live within a 'normal' __main__ (meaning, they
         # shouldn't overtake the execution environment of the script they're
         # embedded in).
 
         # This is overridden in the InteractiveShellEmbed subclass to a no-op.
         main_name = self.user_module.__name__
         sys.modules[main_name] = self.user_module
 
     def init_user_ns(self):
         """Initialize all user-visible namespaces to their minimum defaults.
 
         Certain history lists are also initialized here, as they effectively
         act as user namespaces.
 
         Notes
         -----
         All data structures here are only filled in, they are NOT reset by this
         method.  If they were not empty before, data will simply be added to
         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()
         
         # 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_ns_hidden] + \
                [m.__dict__ for m in self._main_mod_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()
 
     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 iteritems(ns) 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, string_types+(list, tuple)):
             if isinstance(variables, string_types):
                 vlist = variables.split()
             else:
                 vlist = variables
             vdict = {}
             cf = sys._getframe(1)
             for name in vlist:
                 try:
                     vdict[name] = eval(name, cf.f_globals, cf.f_locals)
                 except:
                     print('Could not get variable %s from %s' %
                            (name,cf.f_code.co_name))
         else:
             raise ValueError('variables must be a dict/str/list/tuple')
 
         # Propagate variables to user namespace
         self.user_ns.update(vdict)
 
         # And configure interactive visibility
         user_ns_hidden = self.user_ns_hidden
         if interactive:
             for name in vdict:
                 user_ns_hidden.pop(name, None)
         else:
             user_ns_hidden.update(vdict)
     
     def drop_by_id(self, variables):
         """Remove a dict of variables from the user namespace, if they are the
         same as the values in the dictionary.
         
         This is intended for use by extensions: variables that they've added can
         be taken back out if they are unloaded, without removing any that the
         user has overwritten.
         
         Parameters
         ----------
         variables : dict
           A dictionary mapping object names (as strings) to the objects.
         """
         for name, obj in iteritems(variables):
             if name in self.user_ns and self.user_ns[name] is obj:
                 del self.user_ns[name]
                 self.user_ns_hidden.pop(name, None)
 
     #-------------------------------------------------------------------------
     # Things related to object introspection
     #-------------------------------------------------------------------------
 
     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__),
                            ]
 
         # 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
                     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, parent=self)
         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, string_types):
                 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, string_types):
                     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 show_usage_error(self, exc):
         """Show a short message for UsageErrors
         
         These are special exceptions that shouldn't show a traceback.
         """
         self.write_err("UsageError: %s" % exc)
     
     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.show_usage_error(value)
             else:
                 if exception_only:
                     stb = ['An exception has occurred, use %tb to see '
                            'the full traceback.\n']
                     stb.extend(self.InteractiveTB.get_exception_only(etype,
                                                                      value))
                 else:
                     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
         "<string>" 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):
                 try:
                     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
                 
                 except TypeError:
                     # The history DB can get corrupted so it returns strings
                     # containing null bytes, which readline objects to.
                     continue
 
     @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,
                                      use_readline=self.has_readline,
                                      parent=self,
                                      )
         self.configurables.append(self.Completer)
 
         # Add custom completers to the basic ones built into IPCompleter
         sdisp = self.strdispatchers.get('complete_command', StrDispatch())
         self.strdispatchers['complete_command'] = sdisp
         self.Completer.custom_completers = sdisp
 
         self.set_hook('complete_command', module_completer, str_key = 'import')
         self.set_hook('complete_command', module_completer, str_key = 'from')
         self.set_hook('complete_command', 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,
                                    parent=self,
                                    user_magics=m.UserMagics(self))
         self.configurables.append(self.magics_manager)
 
         # Expose as public API from the magics manager
         self.register_magics = self.magics_manager.register
         self.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
         # FIXME: magic aliases should be defined by the Magics classes
         # or in MagicsManager, not here
         mman.register_alias('ed', 'edit')
         mman.register_alias('hist', 'history')
         mman.register_alias('rep', 'recall')
         mman.register_alias('SVG', 'svg', 'cell')
         mman.register_alias('HTML', 'html', 'cell')
         mman.register_alias('file', 'writefile', 'cell')
 
         # FIXME: Move the color initialization to the DisplayHook, which
         # should be split into a prompt manager and displayhook. We probably
         # even need a centralize colors management object.
         self.magic('colors %s' % self.colors)
     
     # Defined here so that it's included in the documentation
     @functools.wraps(magic.MagicsManager.register_function)
     def register_magic_function(self, func, magic_kind='line', magic_name=None):
         self.magics_manager.register_function(func, 
                                   magic_kind=magic_kind, magic_name=magic_name)
 
     def 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 `%%{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 == '':
             message = '%%{0} is a cell magic, but the cell body is empty.'.format(magic_name)
             if self.find_line_magic(magic_name) is not None:
                 message += ' Did you mean the line magic %{0} (single %)?'.format(magic_name)
             raise UsageError(message)
         else:
             # Note: this is the distance in the stack to the user's frame.
             # This will need to be updated if the internal calling logic gets
             # refactored, or else we'll be expanding the wrong variables.
             stack_depth = 2
             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, string_types):
             themacro = macro.Macro(themacro)
         if not isinstance(themacro, macro.Macro):
             raise ValueError('A macro must be a string or a Macro instance.')
         self.user_ns[name] = themacro
 
     #-------------------------------------------------------------------------
     # Things related to the running of system commands
     #-------------------------------------------------------------------------
 
     def system_piped(self, cmd):
         """Call the given cmd in a subprocess, piping stdout/err
 
         Parameters
         ----------
         cmd : str
           Command to execute (can not end in '&', as background processes are
           not supported.  Should not be a command that expects input
           other than simple text.
         """
         if cmd.rstrip().endswith('&'):
             # this is *far* from a rigorous test
             # We do not support backgrounding processes because we either use
             # pexpect or pipes to read from.  Users can always just call
             # os.system() or use ip.system=ip.system_raw
             # if they really want a background process.
             raise OSError("Background processes not supported.")
 
         # we explicitly do NOT return the subprocess status code, because
         # a non-None value would trigger :func:`sys.displayhook` calls.
         # Instead, we store the exit_code in user_ns.
         self.user_ns['_exit_code'] = system(self.var_expand(cmd, depth=1))
 
     def system_raw(self, cmd):
         """Call the given cmd in a subprocess using os.system on Windows or
         subprocess.call using the system shell on other platforms.
 
         Parameters
         ----------
         cmd : str
           Command to execute.
         """
         cmd = self.var_expand(cmd, depth=1)
         # 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)
             # Call the cmd using the OS shell, instead of the default /bin/sh, if set.
             ec = subprocess.call(cmd, shell=True, executable=os.environ.get('SHELL', None))
             # exit code is positive for program failure, or negative for
             # terminating signal number.
         
         # 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, parent=self)
         self.configurables.append(self.alias_manager)
 
     #-------------------------------------------------------------------------
     # Things related to extensions
     #-------------------------------------------------------------------------
 
     def init_extension_manager(self):
         self.extension_manager = ExtensionManager(shell=self, parent=self)
         self.configurables.append(self.extension_manager)
 
     #-------------------------------------------------------------------------
     # Things related to payloads
     #-------------------------------------------------------------------------
 
     def init_payload(self):
         self.payload_manager = PayloadManager(parent=self)
         self.configurables.append(self.payload_manager)
     
     #-------------------------------------------------------------------------
     # Things related to widgets
     #-------------------------------------------------------------------------
     
     def init_comms(self):
         # not implemented in the base class
         pass
     
     #-------------------------------------------------------------------------
     # Things related to the prefilter
     #-------------------------------------------------------------------------
 
     def init_prefilter(self):
         self.prefilter_manager = PrefilterManager(shell=self, parent=self)
         self.configurables.append(self.prefilter_manager)
         # Ultimately this will be refactored in the new interpreter code, but
         # for now, we should expose the main prefilter method (there's legacy
         # code out there that may rely on this).
         self.prefilter = self.prefilter_manager.prefilter_lines
 
     def auto_rewrite_input(self, cmd):
         """Print to the screen the rewritten form of the user's command.
 
         This shows visual feedback by rewriting input lines that cause
         automatic calling to kick in, like::
 
           /f x
 
         into::
 
           ------> f(x)
 
         after the user's input prompt.  This helps the user understand that the
         input line was transformed automatically by IPython.
         """
         if not self.show_rewritten_input:
             return
         
         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 _user_obj_error(self):
         """return simple exception dict
         
         for use in user_variables / expressions
         """
         
         etype, evalue, tb = self._get_exc_info()
         stb = self.InteractiveTB.get_exception_only(etype, evalue)
         
         exc_info = {
             u'status' : 'error',
             u'traceback' : stb,
             u'ename' : unicode_type(etype.__name__),
             u'evalue' : py3compat.safe_unicode(evalue),
         }
 
         return exc_info
     
     def _format_user_obj(self, obj):
         """format a user object to display dict
         
         for use in user_expressions / variables
         """
         
         data, md = self.display_formatter.format(obj)
         value = {
             'status' : 'ok',
             'data' : data,
             'metadata' : md,
         }
         return 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 rich mime-type repr(s) of each value.
         Each element will be a sub-dict of the same form as a display_data message.
         """
         out = {}
         user_ns = self.user_ns
         
         for varname in names:
             try:
                 value = self._format_user_obj(user_ns[varname])
             except:
                 value = self._user_obj_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 rich mime-typed
         display_data of each value.
         """
         out = {}
         user_ns = self.user_ns
         global_ns = self.user_global_ns
         
         for key, expr in iteritems(expressions):
             try:
                 value = self._format_user_obj(eval(expr, global_ns, user_ns))
             except:
                 value = self._user_obj_error()
             out[key] = value
         return out
 
     #-------------------------------------------------------------------------
     # Things related to the running of code
     #-------------------------------------------------------------------------
 
     def ex(self, cmd):
         """Execute a normal python statement in user namespace."""
         with self.builtin_trap:
             exec(cmd, self.user_global_ns, self.user_ns)
 
     def ev(self, expr):
         """Evaluate python expression expr in user namespace.
 
         Returns the result of evaluation
         """
         with self.builtin_trap:
             return eval(expr, self.user_global_ns, self.user_ns)
 
     def safe_execfile(self, fname, *where, **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 and not kw['exit_ignore']:
                     self.showtraceback(exception_only=True)
             except:
                 if kw['raise_exceptions']:
                     raise
                 # tb offset is 2 because we wrap execfile
                 self.showtraceback(tb_offset=2)
 
     def safe_execfile_ipy(self, fname):
         """Like safe_execfile, but for .ipy or .ipynb files with IPython syntax.
 
         Parameters
         ----------
         fname : str
             The name of the file to execute.  The filename must have a
             .ipy or .ipynb extension.
         """
         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)
         
         def get_cells():
             """generator for sequence of code blocks to run"""
             if fname.endswith('.ipynb'):
                 from IPython.nbformat import current
                 with open(fname) as f:
                     nb = current.read(f, 'json')
                     if not nb.worksheets:
                         return
                     for cell in nb.worksheets[0].cells:
                         if cell.cell_type == 'code':
                             yield cell.input
             else:
                 with open(fname) as f:
                     yield f.read()
 
         with prepended_to_syspath(dname):
             try:
                 for cell in get_cells():
                     # self.run_cell currently captures all exceptions
                     # raised in user code.  It would be nice if there were
                     # versions of run_cell that did raise, so
                     # we could catch the errors.
                     self.run_cell(cell, 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.
 
         `SystemExit` exceptions with status code 0 or None are ignored.
 
         Parameters
         ----------
         mod_name : string
             The name of the module to be executed.
         where : dict
             The globals namespace.
         """
         try:
             try:
                 where.update(
                     runpy.run_module(str(mod_name), run_name="__main__",
                                      alter_sys=True)
                     )
             except SystemExit as status:
                 if status.code:
                     raise
         except:
             self.showtraceback()
             warn('Unknown failure executing module: <%s>' % mod_name)
 
     def _run_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.events.trigger('pre_execute')
+        if not silent:
+            self.events.trigger('pre_run_cell')
+
         # If any of our input transformation (input_transformer_manager or
         # prefilter_manager) raises an exception, we store it in this variable
         # so that we can display the error after logging the input and storing
         # it in the history.
         preprocessing_exc_tuple = None
         try:
             # Static input transformations
             cell = self.input_transformer_manager.transform_cell(raw_cell)
         except SyntaxError:
             preprocessing_exc_tuple = sys.exc_info()
             cell = raw_cell  # cell has to exist so it can be stored/logged
         else:
             if len(cell.splitlines()) == 1:
                 # Dynamic transformations - only applied for single line commands
                 with self.builtin_trap:
                     try:
                         # use prefilter_lines to handle trailing newlines
                         # restore trailing newline for ast.parse
                         cell = self.prefilter_manager.prefilter_lines(cell) + '\n'
                     except Exception:
                         # don't allow prefilter errors to crash IPython
                         preprocessing_exc_tuple = sys.exc_info()
 
         # 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)
 
         # Display the exception if input processing failed.
         if preprocessing_exc_tuple is not None:
             self.showtraceback(preprocessing_exc_tuple)
             if store_history:
                 self.execution_count += 1
             return
 
         # 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:
             cell_name = self.compile.cache(cell, self.execution_count)
 
             with self.display_trap:
                 # Compile to bytecode
                 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
 
                 # Apply AST transformations
                 code_ast = self.transform_ast(code_ast)
 
                 # Execute the user code
                 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 iteritems(self._post_execute)
-
-                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)
+                
+                self.events.trigger('post_execute')
+                if not silent:
+                    self.events.trigger('post_run_cell')
 
         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, 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_matplotlib(self, gui=None):
         """Enable interactive matplotlib and inline figure support.
         
         This takes the following steps:
         
         1. select the appropriate eventloop and matplotlib backend
         2. set up matplotlib for interactive use with that backend
         3. configure formatters for inline figure display
         4. enable the selected gui eventloop
         
         Parameters
         ----------
         gui : optional, string
           If given, dictates the choice of matplotlib GUI backend to use
           (should be one of IPython's supported backends, 'qt', 'osx', 'tk',
           'gtk', 'wx' or 'inline'), otherwise we use the default chosen by
           matplotlib (as dictated by the matplotlib build-time options plus the
           user's matplotlibrc configuration file).  Note that not all backends
           make sense in all contexts, for example a terminal ipython can't
           display figures inline.
         """
         from IPython.core import pylabtools as pt
         gui, backend = pt.find_gui_and_backend(gui, self.pylab_gui_select)
     
         if gui != 'inline':
             # If we have our first gui selection, store it
             if self.pylab_gui_select is None:
                 self.pylab_gui_select = gui
             # Otherwise if they are different
             elif gui != self.pylab_gui_select:
                 print ('Warning: Cannot change to a different GUI toolkit: %s.'
                         ' Using %s instead.' % (gui, self.pylab_gui_select))
                 gui, backend = pt.find_gui_and_backend(self.pylab_gui_select)
         
         pt.activate_matplotlib(backend)
         pt.configure_inline_support(self, backend)
         
         # Now we must activate the gui pylab wants to use, and fix %run to take
         # plot updates into account
         self.enable_gui(gui)
         self.magics_manager.registry['ExecutionMagics'].default_runner = \
             pt.mpl_runner(self.safe_execfile)
         
         return gui, backend
 
     def enable_pylab(self, gui=None, import_all=True, welcome_message=False):
         """Activate pylab support at runtime.
 
         This turns on support for matplotlib, preloads into the interactive
         namespace all of numpy and pylab, and configures IPython to correctly
         interact with the GUI event loop.  The GUI backend to be used can be
         optionally selected with the optional ``gui`` argument.
         
         This method only adds preloading the namespace to InteractiveShell.enable_matplotlib.
 
         Parameters
         ----------
         gui : optional, string
           If given, dictates the choice of matplotlib GUI backend to use
           (should be one of IPython's supported backends, 'qt', 'osx', 'tk',
           'gtk', 'wx' or 'inline'), otherwise we use the default chosen by
           matplotlib (as dictated by the matplotlib build-time options plus the
           user's matplotlibrc configuration file).  Note that not all backends
           make sense in all contexts, for example a terminal ipython can't
           display figures inline.
         import_all : optional, bool, default: True
           Whether to do `from numpy import *` and `from pylab import *`
           in addition to module imports.
         welcome_message : deprecated
           This argument is ignored, no welcome message will be displayed.
         """
         from IPython.core.pylabtools import import_pylab
         
         gui, backend = self.enable_matplotlib(gui)
         
         # We want to prevent the loading of pylab to pollute the user's
         # namespace as shown by the %who* magics, so we execute the activation
         # code in an empty namespace, and we update *both* user_ns and
         # user_ns_hidden with this information.
         ns = {}
         import_pylab(ns, import_all)
         # warn about clobbered names
         ignored = set(["__builtins__"])
         both = set(ns).intersection(self.user_ns).difference(ignored)
         clobbered = [ name for name in both if self.user_ns[name] is not ns[name] ]
         self.user_ns.update(ns)
         self.user_ns_hidden.update(ns)
         return gui, backend, clobbered
 
     #-------------------------------------------------------------------------
     # Utilities
     #-------------------------------------------------------------------------
 
     def var_expand(self, cmd, depth=0, formatter=DollarFormatter()):
         """Expand python variables in a string.
 
         The depth argument indicates how many frames above the caller should
         be walked to look for the local namespace where to expand variables.
 
         The global namespace for expansion is always the user's interactive
         namespace.
         """
         ns = self.user_ns.copy()
         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.mkstemp (created in a tempfile.mkdtemp),
         but it registers the created filename internally so ipython cleans it up
         at exit time.
 
         Optional inputs:
 
           - data(None): if data is given, it gets written out to the temp file
             immediately, and the file is closed again."""
 
         dirname = tempfile.mkdtemp(prefix=prefix)
         self.tempdirs.append(dirname)
 
         handle, filename = tempfile.mkstemp('.py', prefix, dir=dirname)
         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.
 
         raw : bool, optional
             By default, the processed input is used.  If this is true, the raw
             input history is used instead.
 
         Notes
         -----
 
         Slices can be described with two notations:
 
         * ``N:M`` -> standard python form, means including items N...(M-1).
         * ``N-M`` -> include items N..M (closed endpoint).
         """
         lines = self.history_manager.get_range_by_str(range_str, raw=raw)
         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 :
                 # Deferred import
                 try:
                     from urllib.request import urlopen  # Py3
                 except ImportError:
                     from urllib import urlopen
                 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)
             elif os.path.isdir(os.path.expanduser(tgt)):
                 raise ValueError("'%s' is a directory, not a regular file." % 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, string_types):
             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 and folders left around
         for tfile in self.tempfiles:
             try:
                 os.unlink(tfile)
             except OSError:
                 pass
 
         for tdir in self.tempdirs:
             try:
                 os.rmdir(tdir)
             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(with_metaclass(abc.ABCMeta, object)):
     """An abstract base class for InteractiveShell."""
 
 InteractiveShellABC.register(InteractiveShell)

IPython/core/pylabtools.py

@@ -1,374 +1,376 b''
 # -*- coding: utf-8 -*-
 """Pylab (matplotlib) support utilities.
 
 Authors
 -------
 
 * Fernando Perez.
 * Brian Granger
 """
 from __future__ import print_function
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2009  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
 #-----------------------------------------------------------------------------
 
 import sys
 from io import BytesIO
 
 from IPython.core.display import _pngxy
 from IPython.utils.decorators import flag_calls
 from IPython.utils import py3compat
 
 # If user specifies a GUI, that dictates the backend, otherwise we read the
 # user's mpl default from the mpl rc structure
 backends = {'tk': 'TkAgg',
             'gtk': 'GTKAgg',
             'gtk3': 'GTK3Agg',
             'wx': 'WXAgg',
             'qt': 'Qt4Agg', # qt3 not supported
             'qt4': 'Qt4Agg',
             'osx': 'MacOSX',
             'inline' : 'module://IPython.kernel.zmq.pylab.backend_inline'}
 
 # We also need a reverse backends2guis mapping that will properly choose which
 # GUI support to activate based on the desired matplotlib backend.  For the
 # most part it's just a reverse of the above dict, but we also need to add a
 # few others that map to the same GUI manually:
 backend2gui = dict(zip(backends.values(), backends.keys()))
 # Our tests expect backend2gui to just return 'qt'
 backend2gui['Qt4Agg'] = 'qt'
 # In the reverse mapping, there are a few extra valid matplotlib backends that
 # map to the same GUI support
 backend2gui['GTK'] = backend2gui['GTKCairo'] = 'gtk'
 backend2gui['GTK3Cairo'] = 'gtk3'
 backend2gui['WX'] = 'wx'
 backend2gui['CocoaAgg'] = 'osx'
 
 #-----------------------------------------------------------------------------
 # Matplotlib utilities
 #-----------------------------------------------------------------------------
 
 
 def getfigs(*fig_nums):
     """Get a list of matplotlib figures by figure numbers.
 
     If no arguments are given, all available figures are returned.  If the
     argument list contains references to invalid figures, a warning is printed
     but the function continues pasting further figures.
 
     Parameters
     ----------
     figs : tuple
         A tuple of ints giving the figure numbers of the figures to return.
     """
     from matplotlib._pylab_helpers import Gcf
     if not fig_nums:
         fig_managers = Gcf.get_all_fig_managers()
         return [fm.canvas.figure for fm in fig_managers]
     else:
         figs = []
         for num in fig_nums:
             f = Gcf.figs.get(num)
             if f is None:
                 print('Warning: figure %s not available.' % num)
             else:
                 figs.append(f.canvas.figure)
         return figs
 
 
 def figsize(sizex, sizey):
     """Set the default figure size to be [sizex, sizey].
 
     This is just an easy to remember, convenience wrapper that sets::
 
       matplotlib.rcParams['figure.figsize'] = [sizex, sizey]
     """
     import matplotlib
     matplotlib.rcParams['figure.figsize'] = [sizex, sizey]
 
 
 def print_figure(fig, fmt='png', bbox_inches='tight', **kwargs):
     """Print a figure to an image, and return the resulting bytes
     
     Any keyword args are passed to fig.canvas.print_figure,
     such as ``quality`` or ``bbox_inches``.
     """
     from matplotlib import rcParams
     # When there's an empty figure, we shouldn't return anything, otherwise we
     # get big blank areas in the qt console.
     if not fig.axes and not fig.lines:
         return
 
     dpi = rcParams['savefig.dpi']
     if fmt == 'retina':
         dpi = dpi * 2
         fmt = 'png'
     
     # build keyword args
     kw = dict(
         format=fmt,
         fc=fig.get_facecolor(),
         ec=fig.get_edgecolor(),
         dpi=dpi,
         bbox_inches=bbox_inches,
     )
     # **kwargs get higher priority
     kw.update(kwargs)
     
     bytes_io = BytesIO()
     fig.canvas.print_figure(bytes_io, **kw)
     return bytes_io.getvalue()
     
 def retina_figure(fig, **kwargs):
     """format a figure as a pixel-doubled (retina) PNG"""
     pngdata = print_figure(fig, fmt='retina', **kwargs)
     w, h = _pngxy(pngdata)
     metadata = dict(width=w//2, height=h//2)
     return pngdata, metadata
 
 # We need a little factory function here to create the closure where
 # safe_execfile can live.
 def mpl_runner(safe_execfile):
     """Factory to return a matplotlib-enabled runner for %run.
 
     Parameters
     ----------
     safe_execfile : function
       This must be a function with the same interface as the
       :meth:`safe_execfile` method of IPython.
 
     Returns
     -------
     A function suitable for use as the ``runner`` argument of the %run magic
     function.
     """
     
     def mpl_execfile(fname,*where,**kw):
         """matplotlib-aware wrapper around safe_execfile.
 
         Its interface is identical to that of the :func:`execfile` builtin.
 
         This is ultimately a call to execfile(), but wrapped in safeties to
         properly handle interactive rendering."""
 
         import matplotlib
         import matplotlib.pylab as pylab
 
         #print '*** Matplotlib runner ***' # dbg
         # turn off rendering until end of script
         is_interactive = matplotlib.rcParams['interactive']
         matplotlib.interactive(False)
         safe_execfile(fname,*where,**kw)
         matplotlib.interactive(is_interactive)
         # make rendering call now, if the user tried to do it
         if pylab.draw_if_interactive.called:
             pylab.draw()
             pylab.draw_if_interactive.called = False
 
     return mpl_execfile
 
 
 def select_figure_formats(shell, formats, **kwargs):
     """Select figure formats for the inline backend.
 
     Parameters
     ==========
     shell : InteractiveShell
         The main IPython instance.
     formats : str or set
         One or a set of figure formats to enable: 'png', 'retina', 'jpeg', 'svg', 'pdf'.
     **kwargs : any
         Extra keyword arguments to be passed to fig.canvas.print_figure.
     """
     from matplotlib.figure import Figure
     from IPython.kernel.zmq.pylab import backend_inline
 
     svg_formatter = shell.display_formatter.formatters['image/svg+xml']
     png_formatter = shell.display_formatter.formatters['image/png']
     jpg_formatter = shell.display_formatter.formatters['image/jpeg']
     pdf_formatter = shell.display_formatter.formatters['application/pdf']
 
     if isinstance(formats, py3compat.string_types):
         formats = {formats}
     # cast in case of list / tuple
     formats = set(formats)
 
     [ f.pop(Figure, None) for f in shell.display_formatter.formatters.values() ]
     
     supported = {'png', 'png2x', 'retina', 'jpg', 'jpeg', 'svg', 'pdf'}
     bad = formats.difference(supported)
     if bad:
         bs = "%s" % ','.join([repr(f) for f in bad])
         gs = "%s" % ','.join([repr(f) for f in supported])
         raise ValueError("supported formats are: %s not %s" % (gs, bs))
     
     if 'png' in formats:
         png_formatter.for_type(Figure, lambda fig: print_figure(fig, 'png', **kwargs))
     if 'retina' in formats or 'png2x' in formats:
         png_formatter.for_type(Figure, lambda fig: retina_figure(fig, **kwargs))
     if 'jpg' in formats or 'jpeg' in formats:
         jpg_formatter.for_type(Figure, lambda fig: print_figure(fig, 'jpg', **kwargs))
     if 'svg' in formats:
         svg_formatter.for_type(Figure, lambda fig: print_figure(fig, 'svg', **kwargs))
     if 'pdf' in formats:
         pdf_formatter.for_type(Figure, lambda fig: print_figure(fig, 'pdf', **kwargs))
 
 #-----------------------------------------------------------------------------
 # Code for initializing matplotlib and importing pylab
 #-----------------------------------------------------------------------------
 
 
 def find_gui_and_backend(gui=None, gui_select=None):
     """Given a gui string return the gui and mpl backend.
 
     Parameters
     ----------
     gui : str
         Can be one of ('tk','gtk','wx','qt','qt4','inline').
     gui_select : str
         Can be one of ('tk','gtk','wx','qt','qt4','inline').
         This is any gui already selected by the shell.
 
     Returns
     -------
     A tuple of (gui, backend) where backend is one of ('TkAgg','GTKAgg',
     'WXAgg','Qt4Agg','module://IPython.kernel.zmq.pylab.backend_inline').
     """
 
     import matplotlib
 
     if gui and gui != 'auto':
         # select backend based on requested gui
         backend = backends[gui]
     else:
         # We need to read the backend from the original data structure, *not*
         # from mpl.rcParams, since a prior invocation of %matplotlib may have
         # overwritten that.
         # WARNING: this assumes matplotlib 1.1 or newer!!
         backend = matplotlib.rcParamsOrig['backend']
         # In this case, we need to find what the appropriate gui selection call
         # should be for IPython, so we can activate inputhook accordingly
         gui = backend2gui.get(backend, None)
 
         # If we have already had a gui active, we need it and inline are the
         # ones allowed.
         if gui_select and gui != gui_select:
             gui = gui_select
             backend = backends[gui]
 
     return gui, backend
 
 
 def activate_matplotlib(backend):
     """Activate the given backend and set interactive to True."""
 
     import matplotlib
     matplotlib.interactive(True)
     
     # Matplotlib had a bug where even switch_backend could not force
     # the rcParam to update. This needs to be set *before* the module
     # magic of switch_backend().
     matplotlib.rcParams['backend'] = backend
 
     import matplotlib.pyplot
     matplotlib.pyplot.switch_backend(backend)
 
     # This must be imported last in the matplotlib series, after
     # backend/interactivity choices have been made
     import matplotlib.pylab as pylab
 
     pylab.show._needmain = False
     # We need to detect at runtime whether show() is called by the user.
     # For this, we wrap it into a decorator which adds a 'called' flag.
     pylab.draw_if_interactive = flag_calls(pylab.draw_if_interactive)
 
 
 def import_pylab(user_ns, import_all=True):
     """Populate the namespace with pylab-related values.
     
     Imports matplotlib, pylab, numpy, and everything from pylab and numpy.
     
     Also imports a few names from IPython (figsize, display, getfigs)
     
     """
 
     # Import numpy as np/pyplot as plt are conventions we're trying to
     # somewhat standardize on.  Making them available to users by default
     # will greatly help this.
     s = ("import numpy\n"
           "import matplotlib\n"
           "from matplotlib import pylab, mlab, pyplot\n"
           "np = numpy\n"
           "plt = pyplot\n"
           )
     exec(s, user_ns)
     
     if import_all:
         s = ("from matplotlib.pylab import *\n"
              "from numpy import *\n")
         exec(s, user_ns)
     
     # IPython symbols to add
     user_ns['figsize'] = figsize
     from IPython.core.display import display
     # Add display and getfigs to the user's namespace
     user_ns['display'] = display
     user_ns['getfigs'] = getfigs
 
 
 def configure_inline_support(shell, backend):
     """Configure an IPython shell object for matplotlib use.
 
     Parameters
     ----------
     shell : InteractiveShell instance
 
     backend : matplotlib backend
     """
     # If using our svg payload backend, register the post-execution
     # function that will pick up the results for display.  This can only be
     # done with access to the real shell object.
 
     # Note: if we can't load the inline backend, then there's no point
     # continuing (such as in terminal-only shells in environments without
     # zeromq available).
     try:
         from IPython.kernel.zmq.pylab.backend_inline import InlineBackend
     except ImportError:
         return
     from matplotlib import pyplot
 
     cfg = InlineBackend.instance(parent=shell)
     cfg.shell = shell
     if cfg not in shell.configurables:
         shell.configurables.append(cfg)
 
     if backend == backends['inline']:
         from IPython.kernel.zmq.pylab.backend_inline import flush_figures
-        shell.register_post_execute(flush_figures)
+        shell.events.register('post_execute', flush_figures)
 
         # Save rcParams that will be overwrittern
         shell._saved_rcParams = dict()
         for k in cfg.rc:
             shell._saved_rcParams[k] = pyplot.rcParams[k]
         # load inline_rc
         pyplot.rcParams.update(cfg.rc)
     else:
         from IPython.kernel.zmq.pylab.backend_inline import flush_figures
-        if flush_figures in shell._post_execute:
-            shell._post_execute.pop(flush_figures)
+        try:
+            shell.events.unregister('post_execute', flush_figures)
+        except ValueError:
+            pass
         if hasattr(shell, '_saved_rcParams'):
             pyplot.rcParams.update(shell._saved_rcParams)
             del shell._saved_rcParams
 
     # Setup the default figure format
     select_figure_formats(shell, cfg.figure_formats, **cfg.print_figure_kwargs)
 

IPython/core/tests/test_interactiveshell.py

@@ -1,715 +1,730 b''
 # -*- coding: utf-8 -*-
 """Tests for the key interactiveshell module.
 
 Historically the main classes in interactiveshell have been under-tested.  This
 module should grow as many single-method tests as possible to trap many of the
 recurring bugs we seem to encounter with high-level interaction.
 
 Authors
 -------
 * Fernando Perez
 """
 #-----------------------------------------------------------------------------
 #  Copyright (C) 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
 #-----------------------------------------------------------------------------
 # stdlib
 import ast
 import os
 import signal
 import shutil
 import sys
 import tempfile
 import unittest
+try:
+    from unittest import mock
+except ImportError:
+    import mock
 from os.path import join
 
 # third-party
 import nose.tools as nt
 
 # Our own
 from IPython.core.inputtransformer import InputTransformer
 from IPython.testing.decorators import skipif, skip_win32, onlyif_unicode_paths
 from IPython.testing import tools as tt
 from IPython.utils import io
 from IPython.utils import py3compat
 from IPython.utils.py3compat import unicode_type, PY3
 
 if PY3:
     from io import StringIO
 else:
     from StringIO import StringIO
 
 #-----------------------------------------------------------------------------
 # Globals
 #-----------------------------------------------------------------------------
 # This is used by every single test, no point repeating it ad nauseam
 ip = get_ipython()
 
 #-----------------------------------------------------------------------------
 # Tests
 #-----------------------------------------------------------------------------
 
 class InteractiveShellTestCase(unittest.TestCase):
     def test_naked_string_cells(self):
         """Test that cells with only naked strings are fully executed"""
         # First, single-line inputs
         ip.run_cell('"a"\n')
         self.assertEqual(ip.user_ns['_'], 'a')
         # And also multi-line cells
         ip.run_cell('"""a\nb"""\n')
         self.assertEqual(ip.user_ns['_'], 'a\nb')
 
     def test_run_empty_cell(self):
         """Just make sure we don't get a horrible error with a blank
         cell of input. Yes, I did overlook that."""
         old_xc = ip.execution_count
         ip.run_cell('')
         self.assertEqual(ip.execution_count, old_xc)
 
     def test_run_cell_multiline(self):
         """Multi-block, multi-line cells must execute correctly.
         """
         src = '\n'.join(["x=1",
                          "y=2",
                          "if 1:",
                          "    x += 1",
                          "    y += 1",])
         ip.run_cell(src)
         self.assertEqual(ip.user_ns['x'], 2)
         self.assertEqual(ip.user_ns['y'], 3)
 
     def test_multiline_string_cells(self):
         "Code sprinkled with multiline strings should execute (GH-306)"
         ip.run_cell('tmp=0')
         self.assertEqual(ip.user_ns['tmp'], 0)
         ip.run_cell('tmp=1;"""a\nb"""\n')
         self.assertEqual(ip.user_ns['tmp'], 1)
 
     def test_dont_cache_with_semicolon(self):
         "Ending a line with semicolon should not cache the returned object (GH-307)"
         oldlen = len(ip.user_ns['Out'])
         a = ip.run_cell('1;', store_history=True)
         newlen = len(ip.user_ns['Out'])
         self.assertEqual(oldlen, newlen)
         #also test the default caching behavior
         ip.run_cell('1', store_history=True)
         newlen = len(ip.user_ns['Out'])
         self.assertEqual(oldlen+1, newlen)
 
     def test_In_variable(self):
         "Verify that In variable grows with user input (GH-284)"
         oldlen = len(ip.user_ns['In'])
         ip.run_cell('1;', store_history=True)
         newlen = len(ip.user_ns['In'])
         self.assertEqual(oldlen+1, newlen)
         self.assertEqual(ip.user_ns['In'][-1],'1;')
         
     def test_magic_names_in_string(self):
         ip.run_cell('a = """\n%exit\n"""')
         self.assertEqual(ip.user_ns['a'], '\n%exit\n')
     
     def test_trailing_newline(self):
         """test that running !(command) does not raise a SyntaxError"""
         ip.run_cell('!(true)\n', False)
         ip.run_cell('!(true)\n\n\n', False)
     
     def test_gh_597(self):
         """Pretty-printing lists of objects with non-ascii reprs may cause
         problems."""
         class Spam(object):
           def __repr__(self):
             return "\xe9"*50
         import IPython.core.formatters
         f = IPython.core.formatters.PlainTextFormatter()
         f([Spam(),Spam()])
     
 
     def test_future_flags(self):
         """Check that future flags are used for parsing code (gh-777)"""
         ip.run_cell('from __future__ import print_function')
         try:
             ip.run_cell('prfunc_return_val = print(1,2, sep=" ")')
             assert 'prfunc_return_val' in ip.user_ns
         finally:
             # Reset compiler flags so we don't mess up other tests.
             ip.compile.reset_compiler_flags()
 
     def test_future_unicode(self):
         """Check that unicode_literals is imported from __future__ (gh #786)"""
         try:
             ip.run_cell(u'byte_str = "a"')
             assert isinstance(ip.user_ns['byte_str'], str) # string literals are byte strings by default
             ip.run_cell('from __future__ import unicode_literals')
             ip.run_cell(u'unicode_str = "a"')
             assert isinstance(ip.user_ns['unicode_str'], unicode_type) # strings literals are now unicode
         finally:
             # Reset compiler flags so we don't mess up other tests.
             ip.compile.reset_compiler_flags()
     
     def test_can_pickle(self):
         "Can we pickle objects defined interactively (GH-29)"
         ip = get_ipython()
         ip.reset()
         ip.run_cell(("class Mylist(list):\n"
                      "    def __init__(self,x=[]):\n"
                      "        list.__init__(self,x)"))
         ip.run_cell("w=Mylist([1,2,3])")
         
         from pickle import dumps
         
         # We need to swap in our main module - this is only necessary
         # inside the test framework, because IPython puts the interactive module
         # in place (but the test framework undoes this).
         _main = sys.modules['__main__']
         sys.modules['__main__'] = ip.user_module
         try:
             res = dumps(ip.user_ns["w"])
         finally:
             sys.modules['__main__'] = _main
         self.assertTrue(isinstance(res, bytes))
         
     def test_global_ns(self):
         "Code in functions must be able to access variables outside them."
         ip = get_ipython()
         ip.run_cell("a = 10")
         ip.run_cell(("def f(x):\n"
                      "    return x + a"))
         ip.run_cell("b = f(12)")
         self.assertEqual(ip.user_ns["b"], 22)
 
     def test_bad_custom_tb(self):
         """Check that InteractiveShell is protected from bad custom exception handlers"""
         from IPython.utils import io
         save_stderr = io.stderr
         try:
             # capture stderr
             io.stderr = StringIO()
             ip.set_custom_exc((IOError,), lambda etype,value,tb: 1/0)
             self.assertEqual(ip.custom_exceptions, (IOError,))
             ip.run_cell(u'raise IOError("foo")')
             self.assertEqual(ip.custom_exceptions, ())
             self.assertTrue("Custom TB Handler failed" in io.stderr.getvalue())
         finally:
             io.stderr = save_stderr
 
     def test_bad_custom_tb_return(self):
         """Check that InteractiveShell is protected from bad return types in custom exception handlers"""
         from IPython.utils import io
         save_stderr = io.stderr
         try:
             # capture stderr
             io.stderr = StringIO()
             ip.set_custom_exc((NameError,),lambda etype,value,tb, tb_offset=None: 1)
             self.assertEqual(ip.custom_exceptions, (NameError,))
             ip.run_cell(u'a=abracadabra')
             self.assertEqual(ip.custom_exceptions, ())
             self.assertTrue("Custom TB Handler failed" in io.stderr.getvalue())
         finally:
             io.stderr = save_stderr
 
     def test_drop_by_id(self):
         myvars = {"a":object(), "b":object(), "c": object()}
         ip.push(myvars, interactive=False)
         for name in myvars:
             assert name in ip.user_ns, name
             assert name in ip.user_ns_hidden, name
         ip.user_ns['b'] = 12
         ip.drop_by_id(myvars)
         for name in ["a", "c"]:
             assert name not in ip.user_ns, name
             assert name not in ip.user_ns_hidden, name
         assert ip.user_ns['b'] == 12
         ip.reset()
 
     def test_var_expand(self):
         ip.user_ns['f'] = u'Ca\xf1o'
         self.assertEqual(ip.var_expand(u'echo $f'), u'echo Ca\xf1o')
         self.assertEqual(ip.var_expand(u'echo {f}'), u'echo Ca\xf1o')
         self.assertEqual(ip.var_expand(u'echo {f[:-1]}'), u'echo Ca\xf1')
         self.assertEqual(ip.var_expand(u'echo {1*2}'), u'echo 2')
 
         ip.user_ns['f'] = b'Ca\xc3\xb1o'
         # This should not raise any exception:
         ip.var_expand(u'echo $f')
     
     def test_var_expand_local(self):
         """Test local variable expansion in !system and %magic calls"""
         # !system
         ip.run_cell('def test():\n'
                     '    lvar = "ttt"\n'
                     '    ret = !echo {lvar}\n'
                     '    return ret[0]\n')
         res = ip.user_ns['test']()
         nt.assert_in('ttt', res)
         
         # %magic
         ip.run_cell('def makemacro():\n'
                     '    macroname = "macro_var_expand_locals"\n'
                     '    %macro {macroname} codestr\n')
         ip.user_ns['codestr'] = "str(12)"
         ip.run_cell('makemacro()')
         nt.assert_in('macro_var_expand_locals', ip.user_ns)
     
     def test_var_expand_self(self):
         """Test variable expansion with the name 'self', which was failing.
         
         See https://github.com/ipython/ipython/issues/1878#issuecomment-7698218
         """
         ip.run_cell('class cTest:\n'
                     '  classvar="see me"\n'
                     '  def test(self):\n'
                     '    res = !echo Variable: {self.classvar}\n'
                     '    return res[0]\n')
         nt.assert_in('see me', ip.user_ns['cTest']().test())
     
     def test_bad_var_expand(self):
         """var_expand on invalid formats shouldn't raise"""
         # SyntaxError
         self.assertEqual(ip.var_expand(u"{'a':5}"), u"{'a':5}")
         # NameError
         self.assertEqual(ip.var_expand(u"{asdf}"), u"{asdf}")
         # ZeroDivisionError
         self.assertEqual(ip.var_expand(u"{1/0}"), u"{1/0}")
     
-    def test_silent_nopostexec(self):
-        """run_cell(silent=True) doesn't invoke post-exec funcs"""
-        d = dict(called=False)
-        def set_called():
-            d['called'] = True
+    def test_silent_postexec(self):
+        """run_cell(silent=True) doesn't invoke pre/post_run_cell callbacks"""
+        pre_explicit = mock.Mock()
+        pre_always = mock.Mock()
+        post_explicit = mock.Mock()
+        post_always = mock.Mock()
         
-        ip.register_post_execute(set_called)
-        ip.run_cell("1", silent=True)
-        self.assertFalse(d['called'])
-        # double-check that non-silent exec did what we expected
-        # silent to avoid
-        ip.run_cell("1")
-        self.assertTrue(d['called'])
-        # remove post-exec
-        ip._post_execute.pop(set_called)
+        ip.events.register('pre_run_cell', pre_explicit)
+        ip.events.register('pre_execute', pre_always)
+        ip.events.register('post_run_cell', post_explicit)
+        ip.events.register('post_execute', post_always)
+        
+        try:
+            ip.run_cell("1", silent=True)
+            assert pre_always.called
+            assert not pre_explicit.called
+            assert post_always.called
+            assert not post_explicit.called
+            # double-check that non-silent exec did what we expected
+            # silent to avoid
+            ip.run_cell("1")
+            assert pre_explicit.called
+            assert post_explicit.called
+        finally:
+            # remove post-exec
+            ip.events.reset_all()
     
     def test_silent_noadvance(self):
         """run_cell(silent=True) doesn't advance execution_count"""
         ec = ip.execution_count
         # silent should force store_history=False
         ip.run_cell("1", store_history=True, silent=True)
         
         self.assertEqual(ec, ip.execution_count)
         # double-check that non-silent exec did what we expected
         # silent to avoid
         ip.run_cell("1", store_history=True)
         self.assertEqual(ec+1, ip.execution_count)
     
     def test_silent_nodisplayhook(self):
         """run_cell(silent=True) doesn't trigger displayhook"""
         d = dict(called=False)
         
         trap = ip.display_trap
         save_hook = trap.hook
         
         def failing_hook(*args, **kwargs):
             d['called'] = True
         
         try:
             trap.hook = failing_hook
             ip.run_cell("1", silent=True)
             self.assertFalse(d['called'])
             # double-check that non-silent exec did what we expected
             # silent to avoid
             ip.run_cell("1")
             self.assertTrue(d['called'])
         finally:
             trap.hook = save_hook
 
     @skipif(sys.version_info[0] >= 3, "softspace removed in py3")
     def test_print_softspace(self):
         """Verify that softspace is handled correctly when executing multiple
         statements.
 
         In [1]: print 1; print 2
         1
         2
 
         In [2]: print 1,; print 2
         1 2
         """
         
     def test_ofind_line_magic(self):
         from IPython.core.magic import register_line_magic
         
         @register_line_magic
         def lmagic(line):
             "A line magic"
 
         # Get info on line magic
         lfind = ip._ofind('lmagic')
         info = dict(found=True, isalias=False, ismagic=True,
                     namespace = 'IPython internal', obj= lmagic.__wrapped__,
                     parent = None)
         nt.assert_equal(lfind, info)
         
     def test_ofind_cell_magic(self):
         from IPython.core.magic import register_cell_magic
         
         @register_cell_magic
         def cmagic(line, cell):
             "A cell magic"
 
         # Get info on cell magic
         find = ip._ofind('cmagic')
         info = dict(found=True, isalias=False, ismagic=True,
                     namespace = 'IPython internal', obj= cmagic.__wrapped__,
                     parent = None)
         nt.assert_equal(find, info)
     
     def test_custom_exception(self):
         called = []
         def my_handler(shell, etype, value, tb, tb_offset=None):
             called.append(etype)
             shell.showtraceback((etype, value, tb), tb_offset=tb_offset)
         
         ip.set_custom_exc((ValueError,), my_handler)
         try:
             ip.run_cell("raise ValueError('test')")
             # Check that this was called, and only once.
             self.assertEqual(called, [ValueError])
         finally:
             # Reset the custom exception hook
             ip.set_custom_exc((), None)
     
     @skipif(sys.version_info[0] >= 3, "no differences with __future__ in py3")
     def test_future_environment(self):
         "Can we run code with & without the shell's __future__ imports?"
         ip.run_cell("from __future__ import division")
         ip.run_cell("a = 1/2", shell_futures=True)
         self.assertEqual(ip.user_ns['a'], 0.5)
         ip.run_cell("b = 1/2", shell_futures=False)
         self.assertEqual(ip.user_ns['b'], 0)
         
         ip.compile.reset_compiler_flags()
         # This shouldn't leak to the shell's compiler
         ip.run_cell("from __future__ import division \nc=1/2", shell_futures=False)
         self.assertEqual(ip.user_ns['c'], 0.5)
         ip.run_cell("d = 1/2", shell_futures=True)
         self.assertEqual(ip.user_ns['d'], 0)
 
 
 class TestSafeExecfileNonAsciiPath(unittest.TestCase):
 
     @onlyif_unicode_paths
     def setUp(self):
         self.BASETESTDIR = tempfile.mkdtemp()
         self.TESTDIR = join(self.BASETESTDIR, u"åäö")
         os.mkdir(self.TESTDIR)
         with open(join(self.TESTDIR, u"åäötestscript.py"), "w") as sfile:
             sfile.write("pass\n")
         self.oldpath = py3compat.getcwd()
         os.chdir(self.TESTDIR)
         self.fname = u"åäötestscript.py"
 
     def tearDown(self):
         os.chdir(self.oldpath)
         shutil.rmtree(self.BASETESTDIR)
 
     @onlyif_unicode_paths
     def test_1(self):
         """Test safe_execfile with non-ascii path
         """
         ip.safe_execfile(self.fname, {}, raise_exceptions=True)
 
 class ExitCodeChecks(tt.TempFileMixin):
     def test_exit_code_ok(self):
         self.system('exit 0')
         self.assertEqual(ip.user_ns['_exit_code'], 0)
 
     def test_exit_code_error(self):
         self.system('exit 1')
         self.assertEqual(ip.user_ns['_exit_code'], 1)
 
     @skipif(not hasattr(signal, 'SIGALRM'))
     def test_exit_code_signal(self):
         self.mktmp("import signal, time\n"
                    "signal.setitimer(signal.ITIMER_REAL, 0.1)\n"
                    "time.sleep(1)\n")
         self.system("%s %s" % (sys.executable, self.fname))
         self.assertEqual(ip.user_ns['_exit_code'], -signal.SIGALRM)
 
 class TestSystemRaw(unittest.TestCase, ExitCodeChecks):
     system = ip.system_raw
 
     @onlyif_unicode_paths
     def test_1(self):
         """Test system_raw with non-ascii cmd
         """
         cmd = u'''python -c "'åäö'"   '''
         ip.system_raw(cmd)
 
 # TODO: Exit codes are currently ignored on Windows.
 class TestSystemPipedExitCode(unittest.TestCase, ExitCodeChecks):
     system = ip.system_piped
 
     @skip_win32
     def test_exit_code_ok(self):
         ExitCodeChecks.test_exit_code_ok(self)
 
     @skip_win32
     def test_exit_code_error(self):
         ExitCodeChecks.test_exit_code_error(self)
 
     @skip_win32
     def test_exit_code_signal(self):
         ExitCodeChecks.test_exit_code_signal(self)
 
 class TestModules(unittest.TestCase, tt.TempFileMixin):
     def test_extraneous_loads(self):
         """Test we're not loading modules on startup that we shouldn't.
         """
         self.mktmp("import sys\n"
                    "print('numpy' in sys.modules)\n"
                    "print('IPython.parallel' in sys.modules)\n"
                    "print('IPython.kernel.zmq' in sys.modules)\n"
                    )
         out = "False\nFalse\nFalse\n"
         tt.ipexec_validate(self.fname, out)
 
 class Negator(ast.NodeTransformer):
     """Negates all number literals in an AST."""
     def visit_Num(self, node):
         node.n = -node.n
         return node
 
 class TestAstTransform(unittest.TestCase):
     def setUp(self):
         self.negator = Negator()
         ip.ast_transformers.append(self.negator)
     
     def tearDown(self):
         ip.ast_transformers.remove(self.negator)
     
     def test_run_cell(self):
         with tt.AssertPrints('-34'):
             ip.run_cell('print (12 + 22)')
         
         # A named reference to a number shouldn't be transformed.
         ip.user_ns['n'] = 55
         with tt.AssertNotPrints('-55'):
             ip.run_cell('print (n)')
     
     def test_timeit(self):
         called = set()
         def f(x):
             called.add(x)
         ip.push({'f':f})
         
         with tt.AssertPrints("best of "):
             ip.run_line_magic("timeit", "-n1 f(1)")
         self.assertEqual(called, set([-1]))
         called.clear()
         
         with tt.AssertPrints("best of "):
             ip.run_cell_magic("timeit", "-n1 f(2)", "f(3)")
         self.assertEqual(called, set([-2, -3]))
     
     def test_time(self):
         called = []
         def f(x):
             called.append(x)
         ip.push({'f':f})
         
         # Test with an expression
         with tt.AssertPrints("Wall time: "):
             ip.run_line_magic("time", "f(5+9)")
         self.assertEqual(called, [-14])
         called[:] = []
         
         # Test with a statement (different code path)
         with tt.AssertPrints("Wall time: "):
             ip.run_line_magic("time", "a = f(-3 + -2)")
         self.assertEqual(called, [5])
     
     def test_macro(self):
         ip.push({'a':10})
         # The AST transformation makes this do a+=-1
         ip.define_macro("amacro", "a+=1\nprint(a)")
         
         with tt.AssertPrints("9"):
             ip.run_cell("amacro")
         with tt.AssertPrints("8"):
             ip.run_cell("amacro")
 
 class IntegerWrapper(ast.NodeTransformer):
     """Wraps all integers in a call to Integer()"""
     def visit_Num(self, node):
         if isinstance(node.n, int):
             return ast.Call(func=ast.Name(id='Integer', ctx=ast.Load()),
                             args=[node], keywords=[])
         return node
 
 class TestAstTransform2(unittest.TestCase):
     def setUp(self):
         self.intwrapper = IntegerWrapper()
         ip.ast_transformers.append(self.intwrapper)
         
         self.calls = []
         def Integer(*args):
             self.calls.append(args)
             return args
         ip.push({"Integer": Integer})
     
     def tearDown(self):
         ip.ast_transformers.remove(self.intwrapper)
         del ip.user_ns['Integer']
     
     def test_run_cell(self):
         ip.run_cell("n = 2")
         self.assertEqual(self.calls, [(2,)])
         
         # This shouldn't throw an error
         ip.run_cell("o = 2.0")
         self.assertEqual(ip.user_ns['o'], 2.0)
     
     def test_timeit(self):
         called = set()
         def f(x):
             called.add(x)
         ip.push({'f':f})
         
         with tt.AssertPrints("best of "):
             ip.run_line_magic("timeit", "-n1 f(1)")
         self.assertEqual(called, set([(1,)]))
         called.clear()
         
         with tt.AssertPrints("best of "):
             ip.run_cell_magic("timeit", "-n1 f(2)", "f(3)")
         self.assertEqual(called, set([(2,), (3,)]))
 
 class ErrorTransformer(ast.NodeTransformer):
     """Throws an error when it sees a number."""
     def visit_Num(self):
         raise ValueError("test")
 
 class TestAstTransformError(unittest.TestCase):
     def test_unregistering(self):
         err_transformer = ErrorTransformer()
         ip.ast_transformers.append(err_transformer)
         
         with tt.AssertPrints("unregister", channel='stderr'):
             ip.run_cell("1 + 2")
         
         # This should have been removed.
         nt.assert_not_in(err_transformer, ip.ast_transformers)
 
 def test__IPYTHON__():
     # This shouldn't raise a NameError, that's all
     __IPYTHON__
 
 
 class DummyRepr(object):
     def __repr__(self):
         return "DummyRepr"
     
     def _repr_html_(self):
         return "<b>dummy</b>"
     
     def _repr_javascript_(self):
         return "console.log('hi');", {'key': 'value'}
     
 
 def test_user_variables():
     # enable all formatters
     ip.display_formatter.active_types = ip.display_formatter.format_types
     
     ip.user_ns['dummy'] = d = DummyRepr()
     keys = set(['dummy', 'doesnotexist'])
     r = ip.user_variables(keys)
 
     nt.assert_equal(keys, set(r.keys()))
     dummy = r['dummy']
     nt.assert_equal(set(['status', 'data', 'metadata']), set(dummy.keys()))
     nt.assert_equal(dummy['status'], 'ok')
     data = dummy['data']
     metadata = dummy['metadata']
     nt.assert_equal(data.get('text/html'), d._repr_html_())
     js, jsmd = d._repr_javascript_()
     nt.assert_equal(data.get('application/javascript'), js)
     nt.assert_equal(metadata.get('application/javascript'), jsmd)
     
     dne = r['doesnotexist']
     nt.assert_equal(dne['status'], 'error')
     nt.assert_equal(dne['ename'], 'KeyError')
     
     # back to text only
     ip.display_formatter.active_types = ['text/plain']
     
 def test_user_expression():
     # enable all formatters
     ip.display_formatter.active_types = ip.display_formatter.format_types
     query = {
         'a' : '1 + 2',
         'b' : '1/0',
     }
     r = ip.user_expressions(query)
     import pprint
     pprint.pprint(r)
     nt.assert_equal(set(r.keys()), set(query.keys()))
     a = r['a']
     nt.assert_equal(set(['status', 'data', 'metadata']), set(a.keys()))
     nt.assert_equal(a['status'], 'ok')
     data = a['data']
     metadata = a['metadata']
     nt.assert_equal(data.get('text/plain'), '3')
     
     b = r['b']
     nt.assert_equal(b['status'], 'error')
     nt.assert_equal(b['ename'], 'ZeroDivisionError')
     
     # back to text only
     ip.display_formatter.active_types = ['text/plain']
     
 
 
 
 
 class TestSyntaxErrorTransformer(unittest.TestCase):
     """Check that SyntaxError raised by an input transformer is handled by run_cell()"""
 
     class SyntaxErrorTransformer(InputTransformer):
 
         def push(self, line):
             pos = line.find('syntaxerror')
             if pos >= 0:
                 e = SyntaxError('input contains "syntaxerror"')
                 e.text = line
                 e.offset = pos + 1
                 raise e
             return line
 
         def reset(self):
             pass
 
     def setUp(self):
         self.transformer = TestSyntaxErrorTransformer.SyntaxErrorTransformer()
         ip.input_splitter.python_line_transforms.append(self.transformer)
         ip.input_transformer_manager.python_line_transforms.append(self.transformer)
 
     def tearDown(self):
         ip.input_splitter.python_line_transforms.remove(self.transformer)
         ip.input_transformer_manager.python_line_transforms.remove(self.transformer)
 
     def test_syntaxerror_input_transformer(self):
         with tt.AssertPrints('1234'):
             ip.run_cell('1234')
         with tt.AssertPrints('SyntaxError: invalid syntax'):
             ip.run_cell('1 2 3')   # plain python syntax error
         with tt.AssertPrints('SyntaxError: input contains "syntaxerror"'):
             ip.run_cell('2345  # syntaxerror')  # input transformer syntax error
         with tt.AssertPrints('3456'):
             ip.run_cell('3456')
 
 
 

IPython/extensions/autoreload.py

@@ -1,507 +1,505 b''
 """IPython extension to reload modules before executing user code.
 
 ``autoreload`` reloads modules automatically before entering the execution of
 code typed at the IPython prompt.
 
 This makes for example the following workflow possible:
 
 .. sourcecode:: ipython
 
    In [1]: %load_ext autoreload
 
    In [2]: %autoreload 2
 
    In [3]: from foo import some_function
 
    In [4]: some_function()
    Out[4]: 42
 
    In [5]: # open foo.py in an editor and change some_function to return 43
 
    In [6]: some_function()
    Out[6]: 43
 
 The module was reloaded without reloading it explicitly, and the object
 imported with ``from foo import ...`` was also updated.
 
 Usage
 =====
 
 The following magic commands are provided:
 
 ``%autoreload``
 
     Reload all modules (except those excluded by ``%aimport``)
     automatically now.
 
 ``%autoreload 0``
 
     Disable automatic reloading.
 
 ``%autoreload 1``
 
     Reload all modules imported with ``%aimport`` every time before
     executing the Python code typed.
 
 ``%autoreload 2``
 
     Reload all modules (except those excluded by ``%aimport``) every
     time before executing the Python code typed.
 
 ``%aimport``
 
     List modules which are to be automatically imported or not to be imported.
 
 ``%aimport foo``
 
     Import module 'foo' and mark it to be autoreloaded for ``%autoreload 1``
 
 ``%aimport -foo``
 
     Mark module 'foo' to not be autoreloaded.
 
 Caveats
 =======
 
 Reloading Python modules in a reliable way is in general difficult,
 and unexpected things may occur. ``%autoreload`` tries to work around
 common pitfalls by replacing function code objects and parts of
 classes previously in the module with new versions. This makes the
 following things to work:
 
 - Functions and classes imported via 'from xxx import foo' are upgraded
   to new versions when 'xxx' is reloaded.
 
 - Methods and properties of classes are upgraded on reload, so that
   calling 'c.foo()' on an object 'c' created before the reload causes
   the new code for 'foo' to be executed.
 
 Some of the known remaining caveats are:
 
 - Replacing code objects does not always succeed: changing a @property
   in a class to an ordinary method or a method to a member variable
   can cause problems (but in old objects only).
 
 - Functions that are removed (eg. via monkey-patching) from a module
   before it is reloaded are not upgraded.
 
 - C extension modules cannot be reloaded, and so cannot be autoreloaded.
 """
 from __future__ import print_function
 
 skip_doctest = True
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2000 Thomas Heller
 #  Copyright (C) 2008 Pauli Virtanen <[e-mail]>
 #  Copyright (C) 2012  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.
 #-----------------------------------------------------------------------------
 #
 # This IPython module is written by Pauli Virtanen, based on the autoreload
 # code by Thomas Heller.
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import os
 import sys
 import traceback
 import types
 import weakref
 
 try:
     # Reload is not defined by default in Python3.
     reload
 except NameError:
     from imp import reload
 
 from IPython.utils import openpy
 from IPython.utils.py3compat import PY3
 
 #------------------------------------------------------------------------------
 # Autoreload functionality
 #------------------------------------------------------------------------------
 
 class ModuleReloader(object):
     enabled = False
     """Whether this reloader is enabled"""
 
     failed = {}
     """Modules that failed to reload: {module: mtime-on-failed-reload, ...}"""
 
     modules = {}
     """Modules specially marked as autoreloadable."""
 
     skip_modules = {}
     """Modules specially marked as not autoreloadable."""
 
     check_all = True
     """Autoreload all modules, not just those listed in 'modules'"""
 
     old_objects = {}
     """(module-name, name) -> weakref, for replacing old code objects"""
 
     def mark_module_skipped(self, module_name):
         """Skip reloading the named module in the future"""
         try:
             del self.modules[module_name]
         except KeyError:
             pass
         self.skip_modules[module_name] = True
 
     def mark_module_reloadable(self, module_name):
         """Reload the named module in the future (if it is imported)"""
         try:
             del self.skip_modules[module_name]
         except KeyError:
             pass
         self.modules[module_name] = True
 
     def aimport_module(self, module_name):
         """Import a module, and mark it reloadable
 
         Returns
         -------
         top_module : module
             The imported module if it is top-level, or the top-level
         top_name : module
             Name of top_module
 
         """
         self.mark_module_reloadable(module_name)
 
         __import__(module_name)
         top_name = module_name.split('.')[0]
         top_module = sys.modules[top_name]
         return top_module, top_name
 
     def check(self, check_all=False):
         """Check whether some modules need to be reloaded."""
 
         if not self.enabled and not check_all:
             return
 
         if check_all or self.check_all:
             modules = list(sys.modules.keys())
         else:
             modules = list(self.modules.keys())
 
         for modname in modules:
             m = sys.modules.get(modname, None)
 
             if modname in self.skip_modules:
                 continue
 
             if not hasattr(m, '__file__'):
                 continue
 
             if m.__name__ == '__main__':
                 # we cannot reload(__main__)
                 continue
 
             filename = m.__file__
             path, ext = os.path.splitext(filename)
 
             if ext.lower() == '.py':
                 pyc_filename = openpy.cache_from_source(filename)
                 py_filename = filename
             else:
                 pyc_filename = filename
                 try:
                     py_filename = openpy.source_from_cache(filename)
                 except ValueError:
                     continue
 
             try:
                 pymtime = os.stat(py_filename).st_mtime
                 if pymtime <= os.stat(pyc_filename).st_mtime:
                     continue
                 if self.failed.get(py_filename, None) == pymtime:
                     continue
             except OSError:
                 continue
 
             try:
                 superreload(m, reload, self.old_objects)
                 if py_filename in self.failed:
                     del self.failed[py_filename]
             except:
                 print("[autoreload of %s failed: %s]" % (
                         modname, traceback.format_exc(1)), file=sys.stderr)
                 self.failed[py_filename] = pymtime
 
 #------------------------------------------------------------------------------
 # superreload
 #------------------------------------------------------------------------------
 
 if PY3:
     func_attrs = ['__code__', '__defaults__', '__doc__',
                   '__closure__', '__globals__', '__dict__']
 else:
     func_attrs = ['func_code', 'func_defaults', 'func_doc',
                   'func_closure', 'func_globals', 'func_dict']
 
 
 def update_function(old, new):
     """Upgrade the code object of a function"""
     for name in func_attrs:
         try:
             setattr(old, name, getattr(new, name))
         except (AttributeError, TypeError):
             pass
 
 
 def update_class(old, new):
     """Replace stuff in the __dict__ of a class, and upgrade
     method code objects"""
     for key in list(old.__dict__.keys()):
         old_obj = getattr(old, key)
 
         try:
             new_obj = getattr(new, key)
         except AttributeError:
             # obsolete attribute: remove it
             try:
                 delattr(old, key)
             except (AttributeError, TypeError):
                 pass
             continue
 
         if update_generic(old_obj, new_obj): continue
 
         try:
             setattr(old, key, getattr(new, key))
         except (AttributeError, TypeError):
             pass # skip non-writable attributes
 
 
 def update_property(old, new):
     """Replace get/set/del functions of a property"""
     update_generic(old.fdel, new.fdel)
     update_generic(old.fget, new.fget)
     update_generic(old.fset, new.fset)
 
 
 def isinstance2(a, b, typ):
     return isinstance(a, typ) and isinstance(b, typ)
 
 
 UPDATE_RULES = [
     (lambda a, b: isinstance2(a, b, type),
      update_class),
     (lambda a, b: isinstance2(a, b, types.FunctionType),
      update_function),
     (lambda a, b: isinstance2(a, b, property),
      update_property),
 ]
 
 
 if PY3:
     UPDATE_RULES.extend([(lambda a, b: isinstance2(a, b, types.MethodType),
                           lambda a, b: update_function(a.__func__, b.__func__)),
                         ])
 else:
     UPDATE_RULES.extend([(lambda a, b: isinstance2(a, b, types.ClassType),
                           update_class),
                          (lambda a, b: isinstance2(a, b, types.MethodType),
                           lambda a, b: update_function(a.__func__, b.__func__)),
                         ])
 
 
 def update_generic(a, b):
     for type_check, update in UPDATE_RULES:
         if type_check(a, b):
             update(a, b)
             return True
     return False
 
 
 class StrongRef(object):
     def __init__(self, obj):
         self.obj = obj
     def __call__(self):
         return self.obj
 
 
 def superreload(module, reload=reload, old_objects={}):
     """Enhanced version of the builtin reload function.
 
     superreload remembers objects previously in the module, and
 
     - upgrades the class dictionary of every old class in the module
     - upgrades the code object of every old function and method
     - clears the module's namespace before reloading
 
     """
 
     # collect old objects in the module
     for name, obj in list(module.__dict__.items()):
         if not hasattr(obj, '__module__') or obj.__module__ != module.__name__:
             continue
         key = (module.__name__, name)
         try:
             old_objects.setdefault(key, []).append(weakref.ref(obj))
         except TypeError:
             # weakref doesn't work for all types;
             # create strong references for 'important' cases
             if not PY3 and isinstance(obj, types.ClassType):
                 old_objects.setdefault(key, []).append(StrongRef(obj))
 
     # reload module
     try:
         # clear namespace first from old cruft
         old_dict = module.__dict__.copy()
         old_name = module.__name__
         module.__dict__.clear()
         module.__dict__['__name__'] = old_name
         module.__dict__['__loader__'] = old_dict['__loader__']
     except (TypeError, AttributeError, KeyError):
         pass
 
     try:
         module = reload(module)
     except:
         # restore module dictionary on failed reload
         module.__dict__.update(old_dict)
         raise
 
     # iterate over all objects and update functions & classes
     for name, new_obj in list(module.__dict__.items()):
         key = (module.__name__, name)
         if key not in old_objects: continue
 
         new_refs = []
         for old_ref in old_objects[key]:
             old_obj = old_ref()
             if old_obj is None: continue
             new_refs.append(old_ref)
             update_generic(old_obj, new_obj)
 
         if new_refs:
             old_objects[key] = new_refs
         else:
             del old_objects[key]
 
     return module
 
 #------------------------------------------------------------------------------
 # IPython connectivity
 #------------------------------------------------------------------------------
 
-from IPython.core.hooks import TryNext
 from IPython.core.magic import Magics, magics_class, line_magic
 
 @magics_class
 class AutoreloadMagics(Magics):
     def __init__(self, *a, **kw):
         super(AutoreloadMagics, self).__init__(*a, **kw)
         self._reloader = ModuleReloader()
         self._reloader.check_all = False
 
     @line_magic
     def autoreload(self, parameter_s=''):
         r"""%autoreload => Reload modules automatically
 
         %autoreload
         Reload all modules (except those excluded by %aimport) automatically
         now.
 
         %autoreload 0
         Disable automatic reloading.
 
         %autoreload 1
         Reload all modules imported with %aimport every time before executing
         the Python code typed.
 
         %autoreload 2
         Reload all modules (except those excluded by %aimport) every time
         before executing the Python code typed.
 
         Reloading Python modules in a reliable way is in general
         difficult, and unexpected things may occur. %autoreload tries to
         work around common pitfalls by replacing function code objects and
         parts of classes previously in the module with new versions. This
         makes the following things to work:
 
         - Functions and classes imported via 'from xxx import foo' are upgraded
           to new versions when 'xxx' is reloaded.
 
         - Methods and properties of classes are upgraded on reload, so that
           calling 'c.foo()' on an object 'c' created before the reload causes
           the new code for 'foo' to be executed.
 
         Some of the known remaining caveats are:
 
         - Replacing code objects does not always succeed: changing a @property
           in a class to an ordinary method or a method to a member variable
           can cause problems (but in old objects only).
 
         - Functions that are removed (eg. via monkey-patching) from a module
           before it is reloaded are not upgraded.
 
         - C extension modules cannot be reloaded, and so cannot be
           autoreloaded.
 
         """
         if parameter_s == '':
             self._reloader.check(True)
         elif parameter_s == '0':
             self._reloader.enabled = False
         elif parameter_s == '1':
             self._reloader.check_all = False
             self._reloader.enabled = True
         elif parameter_s == '2':
             self._reloader.check_all = True
             self._reloader.enabled = True
 
     @line_magic
     def aimport(self, parameter_s='', stream=None):
         """%aimport => Import modules for automatic reloading.
 
         %aimport
         List modules to automatically import and not to import.
 
         %aimport foo
         Import module 'foo' and mark it to be autoreloaded for %autoreload 1
 
         %aimport -foo
         Mark module 'foo' to not be autoreloaded for %autoreload 1
         """
         modname = parameter_s
         if not modname:
             to_reload = sorted(self._reloader.modules.keys())
             to_skip = sorted(self._reloader.skip_modules.keys())
             if stream is None:
                 stream = sys.stdout
             if self._reloader.check_all:
                 stream.write("Modules to reload:\nall-except-skipped\n")
             else:
                 stream.write("Modules to reload:\n%s\n" % ' '.join(to_reload))
             stream.write("\nModules to skip:\n%s\n" % ' '.join(to_skip))
         elif modname.startswith('-'):
             modname = modname[1:]
             self._reloader.mark_module_skipped(modname)
         else:
             top_module, top_name = self._reloader.aimport_module(modname)
 
             # Inject module to user namespace
             self.shell.push({top_name: top_module})
 
-    def pre_run_code_hook(self, ip):
-        if not self._reloader.enabled:
-            raise TryNext
-        try:
-            self._reloader.check()
-        except:
-            pass
+    def pre_run_cell(self):
+        if self._reloader.enabled:
+            try:
+                self._reloader.check()
+            except:
+                pass
 
 
 def load_ipython_extension(ip):
     """Load the extension in IPython."""
     auto_reload = AutoreloadMagics(ip)
     ip.register_magics(auto_reload)
-    ip.set_hook('pre_run_code_hook', auto_reload.pre_run_code_hook)
+    ip.events.register('pre_run_cell', auto_reload.pre_run_cell)

IPython/extensions/tests/test_autoreload.py

@@ -1,322 +1,321 b''
 """Tests for autoreload extension.
 """
 #-----------------------------------------------------------------------------
 #  Copyright (c) 2012 IPython Development Team.
 #
 #  Distributed under the terms of the Modified BSD License.
 #
 #  The full license is in the file COPYING.txt, distributed with this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import os
 import sys
 import tempfile
 import shutil
 import random
 import time
 
 import nose.tools as nt
 import IPython.testing.tools as tt
 
 from IPython.extensions.autoreload import AutoreloadMagics
-from IPython.core.hooks import TryNext
+from IPython.core.events import EventManager, pre_run_cell
 from IPython.utils.py3compat import PY3
 
 if PY3:
     from io import StringIO
 else:
     from StringIO import StringIO
 
 #-----------------------------------------------------------------------------
 # Test fixture
 #-----------------------------------------------------------------------------
 
 noop = lambda *a, **kw: None
 
 class FakeShell(object):
 
     def __init__(self):
         self.ns = {}
+        self.events = EventManager(self, {'pre_run_cell', pre_run_cell})
         self.auto_magics = AutoreloadMagics(shell=self)
+        self.events.register('pre_run_cell', self.auto_magics.pre_run_cell)
 
     register_magics = set_hook = noop
 
     def run_code(self, code):
-        try:
-            self.auto_magics.pre_run_code_hook(self)
-        except TryNext:
-            pass
+        self.events.trigger('pre_run_cell')
         exec(code, self.ns)
 
     def push(self, items):
         self.ns.update(items)
 
     def magic_autoreload(self, parameter):
         self.auto_magics.autoreload(parameter)
 
     def magic_aimport(self, parameter, stream=None):
         self.auto_magics.aimport(parameter, stream=stream)
 
 
 class Fixture(object):
     """Fixture for creating test module files"""
 
     test_dir = None
     old_sys_path = None
     filename_chars = "abcdefghijklmopqrstuvwxyz0123456789"
 
     def setUp(self):
         self.test_dir = tempfile.mkdtemp()
         self.old_sys_path = list(sys.path)
         sys.path.insert(0, self.test_dir)
         self.shell = FakeShell()
 
     def tearDown(self):
         shutil.rmtree(self.test_dir)
         sys.path = self.old_sys_path
 
         self.test_dir = None
         self.old_sys_path = None
         self.shell = None
 
     def get_module(self):
         module_name = "tmpmod_" + "".join(random.sample(self.filename_chars,20))
         if module_name in sys.modules:
             del sys.modules[module_name]
         file_name = os.path.join(self.test_dir, module_name + ".py")
         return module_name, file_name
 
     def write_file(self, filename, content):
         """
         Write a file, and force a timestamp difference of at least one second
 
         Notes
         -----
         Python's .pyc files record the timestamp of their compilation
         with a time resolution of one second.
 
         Therefore, we need to force a timestamp difference between .py
         and .pyc, without having the .py file be timestamped in the
         future, and without changing the timestamp of the .pyc file
         (because that is stored in the file).  The only reliable way
         to achieve this seems to be to sleep.
         """
 
         # Sleep one second + eps
         time.sleep(1.05)
 
         # Write
         f = open(filename, 'w')
         try:
             f.write(content)
         finally:
             f.close()
 
     def new_module(self, code):
         mod_name, mod_fn = self.get_module()
         f = open(mod_fn, 'w')
         try:
             f.write(code)
         finally:
             f.close()
         return mod_name, mod_fn
 
 #-----------------------------------------------------------------------------
 # Test automatic reloading
 #-----------------------------------------------------------------------------
 
 class TestAutoreload(Fixture):
     def _check_smoketest(self, use_aimport=True):
         """
         Functional test for the automatic reloader using either
         '%autoreload 1' or '%autoreload 2'
         """
 
         mod_name, mod_fn = self.new_module("""
 x = 9
 
 z = 123  # this item will be deleted
 
 def foo(y):
     return y + 3
 
 class Baz(object):
     def __init__(self, x):
         self.x = x
     def bar(self, y):
         return self.x + y
     @property
     def quux(self):
         return 42
     def zzz(self):
         '''This method will be deleted below'''
         return 99
 
 class Bar:    # old-style class: weakref doesn't work for it on Python < 2.7
     def foo(self):
         return 1
 """)
 
         #
         # Import module, and mark for reloading
         #
         if use_aimport:
             self.shell.magic_autoreload("1")
             self.shell.magic_aimport(mod_name)
             stream = StringIO()
             self.shell.magic_aimport("", stream=stream)
             nt.assert_true(("Modules to reload:\n%s" % mod_name) in
                            stream.getvalue())
 
             nt.assert_raises(
                 ImportError,
                 self.shell.magic_aimport, "tmpmod_as318989e89ds")
         else:
             self.shell.magic_autoreload("2")
             self.shell.run_code("import %s" % mod_name)
             stream = StringIO()
             self.shell.magic_aimport("", stream=stream)
             nt.assert_true("Modules to reload:\nall-except-skipped" in
                            stream.getvalue())
         nt.assert_in(mod_name, self.shell.ns)
 
         mod = sys.modules[mod_name]
 
         #
         # Test module contents
         #
         old_foo = mod.foo
         old_obj = mod.Baz(9)
         old_obj2 = mod.Bar()
 
         def check_module_contents():
             nt.assert_equal(mod.x, 9)
             nt.assert_equal(mod.z, 123)
 
             nt.assert_equal(old_foo(0), 3)
             nt.assert_equal(mod.foo(0), 3)
 
             obj = mod.Baz(9)
             nt.assert_equal(old_obj.bar(1), 10)
             nt.assert_equal(obj.bar(1), 10)
             nt.assert_equal(obj.quux, 42)
             nt.assert_equal(obj.zzz(), 99)
 
             obj2 = mod.Bar()
             nt.assert_equal(old_obj2.foo(), 1)
             nt.assert_equal(obj2.foo(), 1)
 
         check_module_contents()
 
         #
         # Simulate a failed reload: no reload should occur and exactly
         # one error message should be printed
         #
         self.write_file(mod_fn, """
 a syntax error
 """)
 
         with tt.AssertPrints(('[autoreload of %s failed:' % mod_name), channel='stderr'):
             self.shell.run_code("pass") # trigger reload
         with tt.AssertNotPrints(('[autoreload of %s failed:' % mod_name), channel='stderr'):
             self.shell.run_code("pass") # trigger another reload
         check_module_contents()
 
         #
         # Rewrite module (this time reload should succeed)
         #
         self.write_file(mod_fn, """
 x = 10
 
 def foo(y):
     return y + 4
 
 class Baz(object):
     def __init__(self, x):
         self.x = x
     def bar(self, y):
         return self.x + y + 1
     @property
     def quux(self):
         return 43
 
 class Bar:    # old-style class
     def foo(self):
         return 2
 """)
 
         def check_module_contents():
             nt.assert_equal(mod.x, 10)
             nt.assert_false(hasattr(mod, 'z'))
 
             nt.assert_equal(old_foo(0), 4) # superreload magic!
             nt.assert_equal(mod.foo(0), 4)
 
             obj = mod.Baz(9)
             nt.assert_equal(old_obj.bar(1), 11) # superreload magic!
             nt.assert_equal(obj.bar(1), 11)
 
             nt.assert_equal(old_obj.quux, 43)
             nt.assert_equal(obj.quux, 43)
 
             nt.assert_false(hasattr(old_obj, 'zzz'))
             nt.assert_false(hasattr(obj, 'zzz'))
 
             obj2 = mod.Bar()
             nt.assert_equal(old_obj2.foo(), 2)
             nt.assert_equal(obj2.foo(), 2)
 
         self.shell.run_code("pass") # trigger reload
         check_module_contents()
 
         #
         # Another failure case: deleted file (shouldn't reload)
         #
         os.unlink(mod_fn)
 
         self.shell.run_code("pass") # trigger reload
         check_module_contents()
 
         #
         # Disable autoreload and rewrite module: no reload should occur
         #
         if use_aimport:
             self.shell.magic_aimport("-" + mod_name)
             stream = StringIO()
             self.shell.magic_aimport("", stream=stream)
             nt.assert_true(("Modules to skip:\n%s" % mod_name) in
                            stream.getvalue())
 
             # This should succeed, although no such module exists
             self.shell.magic_aimport("-tmpmod_as318989e89ds")
         else:
             self.shell.magic_autoreload("0")
 
         self.write_file(mod_fn, """
 x = -99
 """)
 
         self.shell.run_code("pass") # trigger reload
         self.shell.run_code("pass")
         check_module_contents()
 
         #
         # Re-enable autoreload: reload should now occur
         #
         if use_aimport:
             self.shell.magic_aimport(mod_name)
         else:
             self.shell.magic_autoreload("")
 
         self.shell.run_code("pass") # trigger reload
         nt.assert_equal(mod.x, -99)
 
     def test_smoketest_aimport(self):
         self._check_smoketest(use_aimport=True)
 
     def test_smoketest_autoreload(self):
         self._check_smoketest(use_aimport=False)

IPython/kernel/comm/comm.py

@@ -1,140 +1,142 b''
 """Base class for a Comm"""
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2013  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
 #-----------------------------------------------------------------------------
 
 import uuid
 
 from IPython.config import LoggingConfigurable
 from IPython.core.getipython import get_ipython
 
 from IPython.utils.traitlets import Instance, Unicode, Bytes, Bool, Dict, Any
 
 #-----------------------------------------------------------------------------
 # Code
 #-----------------------------------------------------------------------------
 
 class Comm(LoggingConfigurable):
     
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC')
     def _shell_default(self):
         return get_ipython()
     
     iopub_socket = Any()
     def _iopub_socket_default(self):
         return self.shell.kernel.iopub_socket
     session = Instance('IPython.kernel.zmq.session.Session')
     def _session_default(self):
         if self.shell is None:
             return
         return self.shell.kernel.session
     
     target_name = Unicode('comm')
     
     topic = Bytes()
     def _topic_default(self):
         return ('comm-%s' % self.comm_id).encode('ascii')
     
     _open_data = Dict(help="data dict, if any, to be included in comm_open")
     _close_data = Dict(help="data dict, if any, to be included in comm_close")
     
     _msg_callback = Any()
     _close_callback = Any()
     
     _closed = Bool(False)
     comm_id = Unicode()
     def _comm_id_default(self):
         return uuid.uuid4().hex
     
     primary = Bool(True, help="Am I the primary or secondary Comm?")
     
     def __init__(self, target_name='', data=None, **kwargs):
         if target_name:
             kwargs['target_name'] = target_name
         super(Comm, self).__init__(**kwargs)
         get_ipython().comm_manager.register_comm(self)
         if self.primary:
             # I am primary, open my peer.
             self.open(data)
     
     def _publish_msg(self, msg_type, data=None, metadata=None, **keys):
         """Helper for sending a comm message on IOPub"""
         data = {} if data is None else data
         metadata = {} if metadata is None else metadata
         self.session.send(self.iopub_socket, msg_type,
             dict(data=data, comm_id=self.comm_id, **keys),
             metadata=metadata,
             parent=self.shell.get_parent(),
             ident=self.topic,
         )
     
     def __del__(self):
         """trigger close on gc"""
         self.close()
     
     # publishing messages
     
     def open(self, data=None, metadata=None):
         """Open the frontend-side version of this comm"""
         if data is None:
             data = self._open_data
         self._publish_msg('comm_open', data, metadata, target_name=self.target_name)
     
     def close(self, data=None, metadata=None):
         """Close the frontend-side version of this comm"""
         if self._closed:
             # only close once
             return
         if data is None:
             data = self._close_data
         self._publish_msg('comm_close', data, metadata)
         self._closed = True
     
     def send(self, data=None, metadata=None):
         """Send a message to the frontend-side version of this comm"""
         self._publish_msg('comm_msg', data, metadata)
     
     # registering callbacks
     
     def on_close(self, callback):
         """Register a callback for comm_close
         
         Will be called with the `data` of the close message.
         
         Call `on_close(None)` to disable an existing callback.
         """
         self._close_callback = callback
     
     def on_msg(self, callback):
         """Register a callback for comm_msg
         
         Will be called with the `data` of any comm_msg messages.
         
         Call `on_msg(None)` to disable an existing callback.
         """
         self._msg_callback = callback
     
     # handling of incoming messages
     
     def handle_close(self, msg):
         """Handle a comm_close message"""
         self.log.debug("handle_close[%s](%s)", self.comm_id, msg)
         if self._close_callback:
             self._close_callback(msg)
     
     def handle_msg(self, msg):
         """Handle a comm_msg message"""
         self.log.debug("handle_msg[%s](%s)", self.comm_id, msg)
         if self._msg_callback:
+            self.shell.events.trigger('pre_execute')
             self._msg_callback(msg)
+            self.shell.events.trigger('post_execute')
 
 
 __all__ = ['Comm']

IPython/utils/signatures.py

@@ -1,819 +1,813 b''
-"""Function signature objects for callables
+"""Function signature objects for callables.
 
 Back port of Python 3.3's function signature tools from the inspect module,
-modified to be compatible with Python 2.6, 2.7 and 3.2+.
+modified to be compatible with Python 2.7 and 3.2+.
 """
 
 #-----------------------------------------------------------------------------
 #  Python 3.3 stdlib inspect.py is public domain
 # 
 #  Backports Copyright (C) 2013 Aaron Iles
 #  Used under Apache License Version 2.0
 #
 #  Further Changes are Copyright (C) 2013 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.
 #-----------------------------------------------------------------------------
 
 from __future__ import absolute_import, division, print_function
 import itertools
 import functools
 import re
 import types
 
 
 # patch for single-file
 # we don't support 2.6, so we can just import OrderedDict
 from collections import OrderedDict
 
 __version__ = '0.3'
 # end patch
 
 __all__ = ['BoundArguments', 'Parameter', 'Signature', 'signature']
 
 
 _WrapperDescriptor = type(type.__call__)
 _MethodWrapper = type(all.__call__)
 
 _NonUserDefinedCallables = (_WrapperDescriptor,
                             _MethodWrapper,
                             types.BuiltinFunctionType)
 
 
 def formatannotation(annotation, base_module=None):
     if isinstance(annotation, type):
         if annotation.__module__ in ('builtins', '__builtin__', base_module):
             return annotation.__name__
         return annotation.__module__+'.'+annotation.__name__
     return repr(annotation)
 
 
 def _get_user_defined_method(cls, method_name, *nested):
     try:
         if cls is type:
             return
         meth = getattr(cls, method_name)
         for name in nested:
             meth = getattr(meth, name, meth)
     except AttributeError:
         return
     else:
         if not isinstance(meth, _NonUserDefinedCallables):
             # Once '__signature__' will be added to 'C'-level
             # callables, this check won't be necessary
             return meth
 
 
 def signature(obj):
     '''Get a signature object for the passed callable.'''
 
     if not callable(obj):
         raise TypeError('{0!r} is not a callable object'.format(obj))
 
     if isinstance(obj, types.MethodType):
         # In this case we skip the first parameter of the underlying
         # function (usually `self` or `cls`).
         sig = signature(obj.__func__)
         return sig.replace(parameters=tuple(sig.parameters.values())[1:])
 
     try:
         sig = obj.__signature__
     except AttributeError:
         pass
     else:
         if sig is not None:
             return sig
 
     try:
         # Was this function wrapped by a decorator?
         wrapped = obj.__wrapped__
     except AttributeError:
         pass
     else:
         return signature(wrapped)
 
     if isinstance(obj, types.FunctionType):
         return Signature.from_function(obj)
 
     if isinstance(obj, functools.partial):
         sig = signature(obj.func)
 
         new_params = OrderedDict(sig.parameters.items())
 
         partial_args = obj.args or ()
         partial_keywords = obj.keywords or {}
         try:
             ba = sig.bind_partial(*partial_args, **partial_keywords)
         except TypeError as ex:
             msg = 'partial object {0!r} has incorrect arguments'.format(obj)
             raise ValueError(msg)
 
         for arg_name, arg_value in ba.arguments.items():
             param = new_params[arg_name]
             if arg_name in partial_keywords:
                 # We set a new default value, because the following code
                 # is correct:
                 #
                 #   >>> def foo(a): print(a)
                 #   >>> print(partial(partial(foo, a=10), a=20)())
                 #   20
                 #   >>> print(partial(partial(foo, a=10), a=20)(a=30))
                 #   30
                 #
                 # So, with 'partial' objects, passing a keyword argument is
                 # like setting a new default value for the corresponding
                 # parameter
                 #
                 # We also mark this parameter with '_partial_kwarg'
                 # flag.  Later, in '_bind', the 'default' value of this
                 # parameter will be added to 'kwargs', to simulate
                 # the 'functools.partial' real call.
                 new_params[arg_name] = param.replace(default=arg_value,
                                                      _partial_kwarg=True)
 
             elif (param.kind not in (_VAR_KEYWORD, _VAR_POSITIONAL) and
                             not param._partial_kwarg):
                 new_params.pop(arg_name)
 
         return sig.replace(parameters=new_params.values())
 
     sig = None
     if isinstance(obj, type):
         # obj is a class or a metaclass
 
         # First, let's see if it has an overloaded __call__ defined
         # in its metaclass
         call = _get_user_defined_method(type(obj), '__call__')
         if call is not None:
             sig = signature(call)
         else:
             # Now we check if the 'obj' class has a '__new__' method
             new = _get_user_defined_method(obj, '__new__')
             if new is not None:
                 sig = signature(new)
             else:
                 # Finally, we should have at least __init__ implemented
                 init = _get_user_defined_method(obj, '__init__')
                 if init is not None:
                     sig = signature(init)
     elif not isinstance(obj, _NonUserDefinedCallables):
         # An object with __call__
         # We also check that the 'obj' is not an instance of
         # _WrapperDescriptor or _MethodWrapper to avoid
         # infinite recursion (and even potential segfault)
         call = _get_user_defined_method(type(obj), '__call__', 'im_func')
         if call is not None:
             sig = signature(call)
 
     if sig is not None:
         return sig
 
     if isinstance(obj, types.BuiltinFunctionType):
         # Raise a nicer error message for builtins
         msg = 'no signature found for builtin function {0!r}'.format(obj)
         raise ValueError(msg)
 
     raise ValueError('callable {0!r} is not supported by signature'.format(obj))
 
 
 class _void(object):
     '''A private marker - used in Parameter & Signature'''
 
 
 class _empty(object):
     pass
 
 
 class _ParameterKind(int):
     def __new__(self, *args, **kwargs):
         obj = int.__new__(self, *args)
         obj._name = kwargs['name']
         return obj
 
     def __str__(self):
         return self._name
 
     def __repr__(self):
         return '<_ParameterKind: {0!r}>'.format(self._name)
 
 
 _POSITIONAL_ONLY        = _ParameterKind(0, name='POSITIONAL_ONLY')
 _POSITIONAL_OR_KEYWORD  = _ParameterKind(1, name='POSITIONAL_OR_KEYWORD')
 _VAR_POSITIONAL         = _ParameterKind(2, name='VAR_POSITIONAL')
 _KEYWORD_ONLY           = _ParameterKind(3, name='KEYWORD_ONLY')
 _VAR_KEYWORD            = _ParameterKind(4, name='VAR_KEYWORD')
 
 
 class Parameter(object):
     '''Represents a parameter in a function signature.
 
     Has the following public attributes:
 
     * name : str
         The name of the parameter as a string.
     * default : object
         The default value for the parameter if specified.  If the
         parameter has no default value, this attribute is not set.
     * annotation
         The annotation for the parameter if specified.  If the
         parameter has no annotation, this attribute is not set.
     * kind : str
         Describes how argument values are bound to the parameter.
         Possible values: `Parameter.POSITIONAL_ONLY`,
         `Parameter.POSITIONAL_OR_KEYWORD`, `Parameter.VAR_POSITIONAL`,
         `Parameter.KEYWORD_ONLY`, `Parameter.VAR_KEYWORD`.
     '''
 
     __slots__ = ('_name', '_kind', '_default', '_annotation', '_partial_kwarg')
 
     POSITIONAL_ONLY         = _POSITIONAL_ONLY
     POSITIONAL_OR_KEYWORD   = _POSITIONAL_OR_KEYWORD
     VAR_POSITIONAL          = _VAR_POSITIONAL
     KEYWORD_ONLY            = _KEYWORD_ONLY
     VAR_KEYWORD             = _VAR_KEYWORD
 
     empty = _empty
 
     def __init__(self, name, kind, default=_empty, annotation=_empty,
                  _partial_kwarg=False):
 
         if kind not in (_POSITIONAL_ONLY, _POSITIONAL_OR_KEYWORD,
                         _VAR_POSITIONAL, _KEYWORD_ONLY, _VAR_KEYWORD):
             raise ValueError("invalid value for 'Parameter.kind' attribute")
         self._kind = kind
 
         if default is not _empty:
             if kind in (_VAR_POSITIONAL, _VAR_KEYWORD):
                 msg = '{0} parameters cannot have default values'.format(kind)
                 raise ValueError(msg)
         self._default = default
         self._annotation = annotation
 
         if name is None:
             if kind != _POSITIONAL_ONLY:
                 raise ValueError("None is not a valid name for a "
                                  "non-positional-only parameter")
             self._name = name
         else:
             name = str(name)
             if kind != _POSITIONAL_ONLY and not re.match(r'[a-z_]\w*$', name, re.I):
                 msg = '{0!r} is not a valid parameter name'.format(name)
                 raise ValueError(msg)
             self._name = name
 
         self._partial_kwarg = _partial_kwarg
 
     @property
     def name(self):
         return self._name
 
     @property
     def default(self):
         return self._default
 
     @property
     def annotation(self):
         return self._annotation
 
     @property
     def kind(self):
         return self._kind
 
     def replace(self, name=_void, kind=_void, annotation=_void,
                 default=_void, _partial_kwarg=_void):
         '''Creates a customized copy of the Parameter.'''
 
         if name is _void:
             name = self._name
 
         if kind is _void:
             kind = self._kind
 
         if annotation is _void:
             annotation = self._annotation
 
         if default is _void:
             default = self._default
 
         if _partial_kwarg is _void:
             _partial_kwarg = self._partial_kwarg
 
         return type(self)(name, kind, default=default, annotation=annotation,
                           _partial_kwarg=_partial_kwarg)
 
     def __str__(self):
         kind = self.kind
 
         formatted = self._name
         if kind == _POSITIONAL_ONLY:
             if formatted is None:
                 formatted = ''
             formatted = '<{0}>'.format(formatted)
 
         # Add annotation and default value
         if self._annotation is not _empty:
             formatted = '{0}:{1}'.format(formatted,
                                        formatannotation(self._annotation))
 
         if self._default is not _empty:
             formatted = '{0}={1}'.format(formatted, repr(self._default))
 
         if kind == _VAR_POSITIONAL:
             formatted = '*' + formatted
         elif kind == _VAR_KEYWORD:
             formatted = '**' + formatted
 
         return formatted
 
     def __repr__(self):
         return '<{0} at {1:#x} {2!r}>'.format(self.__class__.__name__,
                                            id(self), self.name)
 
     def __hash__(self):
         msg = "unhashable type: '{0}'".format(self.__class__.__name__)
         raise TypeError(msg)
 
     def __eq__(self, other):
         return (issubclass(other.__class__, Parameter) and
                 self._name == other._name and
                 self._kind == other._kind and
                 self._default == other._default and
                 self._annotation == other._annotation)
 
     def __ne__(self, other):
         return not self.__eq__(other)
 
 
 class BoundArguments(object):
-    '''Result of `Signature.bind` call.  Holds the mapping of arguments
+    '''Result of :meth:`Signature.bind` call.  Holds the mapping of arguments
     to the function's parameters.
 
     Has the following public attributes:
 
-    * arguments : OrderedDict
-        An ordered mutable mapping of parameters' names to arguments' values.
-        Does not contain arguments' default values.
-    * signature : Signature
-        The Signature object that created this instance.
-    * args : tuple
-        Tuple of positional arguments values.
-    * kwargs : dict
-        Dict of keyword arguments values.
+    arguments : :class:`collections.OrderedDict`
+      An ordered mutable mapping of parameters' names to arguments' values.
+      Does not contain arguments' default values.
+    signature : :class:`Signature`
+      The Signature object that created this instance.
+    args : tuple
+      Tuple of positional arguments values.
+    kwargs : dict
+      Dict of keyword arguments values.
     '''
 
     def __init__(self, signature, arguments):
         self.arguments = arguments
         self._signature = signature
 
     @property
     def signature(self):
         return self._signature
 
     @property
     def args(self):
         args = []
         for param_name, param in self._signature.parameters.items():
             if (param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY) or
                                                     param._partial_kwarg):
                 # Keyword arguments mapped by 'functools.partial'
                 # (Parameter._partial_kwarg is True) are mapped
                 # in 'BoundArguments.kwargs', along with VAR_KEYWORD &
                 # KEYWORD_ONLY
                 break
 
             try:
                 arg = self.arguments[param_name]
             except KeyError:
                 # We're done here. Other arguments
                 # will be mapped in 'BoundArguments.kwargs'
                 break
             else:
                 if param.kind == _VAR_POSITIONAL:
                     # *args
                     args.extend(arg)
                 else:
                     # plain argument
                     args.append(arg)
 
         return tuple(args)
 
     @property
     def kwargs(self):
         kwargs = {}
         kwargs_started = False
         for param_name, param in self._signature.parameters.items():
             if not kwargs_started:
                 if (param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY) or
                                                 param._partial_kwarg):
                     kwargs_started = True
                 else:
                     if param_name not in self.arguments:
                         kwargs_started = True
                         continue
 
             if not kwargs_started:
                 continue
 
             try:
                 arg = self.arguments[param_name]
             except KeyError:
                 pass
             else:
                 if param.kind == _VAR_KEYWORD:
                     # **kwargs
                     kwargs.update(arg)
                 else:
                     # plain keyword argument
                     kwargs[param_name] = arg
 
         return kwargs
 
     def __hash__(self):
         msg = "unhashable type: '{0}'".format(self.__class__.__name__)
         raise TypeError(msg)
 
     def __eq__(self, other):
         return (issubclass(other.__class__, BoundArguments) and
                 self.signature == other.signature and
                 self.arguments == other.arguments)
 
     def __ne__(self, other):
         return not self.__eq__(other)
 
 
 class Signature(object):
     '''A Signature object represents the overall signature of a function.
     It stores a Parameter object for each parameter accepted by the
     function, as well as information specific to the function itself.
 
-    A Signature object has the following public attributes and methods:
-
-    * parameters : OrderedDict
-        An ordered mapping of parameters' names to the corresponding
-        Parameter objects (keyword-only arguments are in the same order
-        as listed in `code.co_varnames`).
-    * return_annotation : object
-        The annotation for the return type of the function if specified.
-        If the function has no annotation for its return type, this
-        attribute is not set.
-    * bind(*args, **kwargs) -> BoundArguments
-        Creates a mapping from positional and keyword arguments to
-        parameters.
-    * bind_partial(*args, **kwargs) -> BoundArguments
-        Creates a partial mapping from positional and keyword arguments
-        to parameters (simulating 'functools.partial' behavior.)
+    A Signature object has the following public attributes:
+
+    parameters : :class:`collections.OrderedDict`
+      An ordered mapping of parameters' names to the corresponding
+      Parameter objects (keyword-only arguments are in the same order
+      as listed in `code.co_varnames`).
+    return_annotation
+      The annotation for the return type of the function if specified.
+      If the function has no annotation for its return type, this
+      attribute is not set.
     '''
 
     __slots__ = ('_return_annotation', '_parameters')
 
     _parameter_cls = Parameter
     _bound_arguments_cls = BoundArguments
 
     empty = _empty
 
     def __init__(self, parameters=None, return_annotation=_empty,
                  __validate_parameters__=True):
         '''Constructs Signature from the given list of Parameter
         objects and 'return_annotation'.  All arguments are optional.
         '''
 
         if parameters is None:
             params = OrderedDict()
         else:
             if __validate_parameters__:
                 params = OrderedDict()
                 top_kind = _POSITIONAL_ONLY
 
                 for idx, param in enumerate(parameters):
                     kind = param.kind
                     if kind < top_kind:
                         msg = 'wrong parameter order: {0} before {1}'
                         msg = msg.format(top_kind, param.kind)
                         raise ValueError(msg)
                     else:
                         top_kind = kind
 
                     name = param.name
                     if name is None:
                         name = str(idx)
                         param = param.replace(name=name)
 
                     if name in params:
                         msg = 'duplicate parameter name: {0!r}'.format(name)
                         raise ValueError(msg)
                     params[name] = param
             else:
                 params = OrderedDict(((param.name, param)
                                                 for param in parameters))
 
         self._parameters = params
         self._return_annotation = return_annotation
 
     @classmethod
     def from_function(cls, func):
         '''Constructs Signature for the given python function'''
 
         if not isinstance(func, types.FunctionType):
             raise TypeError('{0!r} is not a Python function'.format(func))
 
         Parameter = cls._parameter_cls
 
         # Parameter information.
         func_code = func.__code__
         pos_count = func_code.co_argcount
         arg_names = func_code.co_varnames
         positional = tuple(arg_names[:pos_count])
         keyword_only_count = getattr(func_code, 'co_kwonlyargcount', 0)
         keyword_only = arg_names[pos_count:(pos_count + keyword_only_count)]
         annotations = getattr(func, '__annotations__', {})
         defaults = func.__defaults__
         kwdefaults = getattr(func, '__kwdefaults__', None)
 
         if defaults:
             pos_default_count = len(defaults)
         else:
             pos_default_count = 0
 
         parameters = []
 
         # Non-keyword-only parameters w/o defaults.
         non_default_count = pos_count - pos_default_count
         for name in positional[:non_default_count]:
             annotation = annotations.get(name, _empty)
             parameters.append(Parameter(name, annotation=annotation,
                                         kind=_POSITIONAL_OR_KEYWORD))
 
         # ... w/ defaults.
         for offset, name in enumerate(positional[non_default_count:]):
             annotation = annotations.get(name, _empty)
             parameters.append(Parameter(name, annotation=annotation,
                                         kind=_POSITIONAL_OR_KEYWORD,
                                         default=defaults[offset]))
 
         # *args
         if func_code.co_flags & 0x04:
             name = arg_names[pos_count + keyword_only_count]
             annotation = annotations.get(name, _empty)
             parameters.append(Parameter(name, annotation=annotation,
                                         kind=_VAR_POSITIONAL))
 
         # Keyword-only parameters.
         for name in keyword_only:
             default = _empty
             if kwdefaults is not None:
                 default = kwdefaults.get(name, _empty)
 
             annotation = annotations.get(name, _empty)
             parameters.append(Parameter(name, annotation=annotation,
                                         kind=_KEYWORD_ONLY,
                                         default=default))
         # **kwargs
         if func_code.co_flags & 0x08:
             index = pos_count + keyword_only_count
             if func_code.co_flags & 0x04:
                 index += 1
 
             name = arg_names[index]
             annotation = annotations.get(name, _empty)
             parameters.append(Parameter(name, annotation=annotation,
                                         kind=_VAR_KEYWORD))
 
         return cls(parameters,
                    return_annotation=annotations.get('return', _empty),
                    __validate_parameters__=False)
 
     @property
     def parameters(self):
         try:
             return types.MappingProxyType(self._parameters)
         except AttributeError:
             return OrderedDict(self._parameters.items())
 
     @property
     def return_annotation(self):
         return self._return_annotation
 
     def replace(self, parameters=_void, return_annotation=_void):
         '''Creates a customized copy of the Signature.
         Pass 'parameters' and/or 'return_annotation' arguments
         to override them in the new copy.
         '''
 
         if parameters is _void:
             parameters = self.parameters.values()
 
         if return_annotation is _void:
             return_annotation = self._return_annotation
 
         return type(self)(parameters,
                           return_annotation=return_annotation)
 
     def __hash__(self):
         msg = "unhashable type: '{0}'".format(self.__class__.__name__)
         raise TypeError(msg)
 
     def __eq__(self, other):
         if (not issubclass(type(other), Signature) or
                     self.return_annotation != other.return_annotation or
                     len(self.parameters) != len(other.parameters)):
             return False
 
         other_positions = dict((param, idx)
                            for idx, param in enumerate(other.parameters.keys()))
 
         for idx, (param_name, param) in enumerate(self.parameters.items()):
             if param.kind == _KEYWORD_ONLY:
                 try:
                     other_param = other.parameters[param_name]
                 except KeyError:
                     return False
                 else:
                     if param != other_param:
                         return False
             else:
                 try:
                     other_idx = other_positions[param_name]
                 except KeyError:
                     return False
                 else:
                     if (idx != other_idx or
                                     param != other.parameters[param_name]):
                         return False
 
         return True
 
     def __ne__(self, other):
         return not self.__eq__(other)
 
     def _bind(self, args, kwargs, partial=False):
         '''Private method.  Don't use directly.'''
 
         arguments = OrderedDict()
 
         parameters = iter(self.parameters.values())
         parameters_ex = ()
         arg_vals = iter(args)
 
         if partial:
             # Support for binding arguments to 'functools.partial' objects.
             # See 'functools.partial' case in 'signature()' implementation
             # for details.
             for param_name, param in self.parameters.items():
                 if (param._partial_kwarg and param_name not in kwargs):
                     # Simulating 'functools.partial' behavior
                     kwargs[param_name] = param.default
 
         while True:
             # Let's iterate through the positional arguments and corresponding
             # parameters
             try:
                 arg_val = next(arg_vals)
             except StopIteration:
                 # No more positional arguments
                 try:
                     param = next(parameters)
                 except StopIteration:
                     # No more parameters. That's it. Just need to check that
                     # we have no `kwargs` after this while loop
                     break
                 else:
                     if param.kind == _VAR_POSITIONAL:
                         # That's OK, just empty *args.  Let's start parsing
                         # kwargs
                         break
                     elif param.name in kwargs:
                         if param.kind == _POSITIONAL_ONLY:
                             msg = '{arg!r} parameter is positional only, ' \
                                   'but was passed as a keyword'
                             msg = msg.format(arg=param.name)
                             raise TypeError(msg)
                         parameters_ex = (param,)
                         break
                     elif (param.kind == _VAR_KEYWORD or
                                                 param.default is not _empty):
                         # That's fine too - we have a default value for this
                         # parameter.  So, lets start parsing `kwargs`, starting
                         # with the current parameter
                         parameters_ex = (param,)
                         break
                     else:
                         if partial:
                             parameters_ex = (param,)
                             break
                         else:
                             msg = '{arg!r} parameter lacking default value'
                             msg = msg.format(arg=param.name)
                             raise TypeError(msg)
             else:
                 # We have a positional argument to process
                 try:
                     param = next(parameters)
                 except StopIteration:
                     raise TypeError('too many positional arguments')
                 else:
                     if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY):
                         # Looks like we have no parameter for this positional
                         # argument
                         raise TypeError('too many positional arguments')
 
                     if param.kind == _VAR_POSITIONAL:
                         # We have an '*args'-like argument, let's fill it with
                         # all positional arguments we have left and move on to
                         # the next phase
                         values = [arg_val]
                         values.extend(arg_vals)
                         arguments[param.name] = tuple(values)
                         break
 
                     if param.name in kwargs:
                         raise TypeError('multiple values for argument '
                                         '{arg!r}'.format(arg=param.name))
 
                     arguments[param.name] = arg_val
 
         # Now, we iterate through the remaining parameters to process
         # keyword arguments
         kwargs_param = None
         for param in itertools.chain(parameters_ex, parameters):
             if param.kind == _POSITIONAL_ONLY:
                 # This should never happen in case of a properly built
                 # Signature object (but let's have this check here
                 # to ensure correct behaviour just in case)
                 raise TypeError('{arg!r} parameter is positional only, '
                                 'but was passed as a keyword'. \
                                 format(arg=param.name))
 
             if param.kind == _VAR_KEYWORD:
                 # Memorize that we have a '**kwargs'-like parameter
                 kwargs_param = param
                 continue
 
             param_name = param.name
             try:
                 arg_val = kwargs.pop(param_name)
             except KeyError:
                 # We have no value for this parameter.  It's fine though,
                 # if it has a default value, or it is an '*args'-like
                 # parameter, left alone by the processing of positional
                 # arguments.
                 if (not partial and param.kind != _VAR_POSITIONAL and
                                                     param.default is _empty):
                     raise TypeError('{arg!r} parameter lacking default value'. \
                                     format(arg=param_name))
 
             else:
                 arguments[param_name] = arg_val
 
         if kwargs:
             if kwargs_param is not None:
                 # Process our '**kwargs'-like parameter
                 arguments[kwargs_param.name] = kwargs
             else:
                 raise TypeError('too many keyword arguments')
 
         return self._bound_arguments_cls(self, arguments)
 
     def bind(self, *args, **kwargs):
-        '''Get a BoundArguments object, that maps the passed `args`
-        and `kwargs` to the function's signature.  Raises `TypeError`
+        '''Get a :class:`BoundArguments` object, that maps the passed `args`
+        and `kwargs` to the function's signature.  Raises :exc:`TypeError`
         if the passed arguments can not be bound.
         '''
         return self._bind(args, kwargs)
 
     def bind_partial(self, *args, **kwargs):
-        '''Get a BoundArguments object, that partially maps the
+        '''Get a :class:`BoundArguments` object, that partially maps the
         passed `args` and `kwargs` to the function's signature.
-        Raises `TypeError` if the passed arguments can not be bound.
+        Raises :exc:`TypeError` if the passed arguments can not be bound.
         '''
         return self._bind(args, kwargs, partial=True)
 
     def __str__(self):
         result = []
         render_kw_only_separator = True
         for idx, param in enumerate(self.parameters.values()):
             formatted = str(param)
 
             kind = param.kind
             if kind == _VAR_POSITIONAL:
                 # OK, we have an '*args'-like parameter, so we won't need
                 # a '*' to separate keyword-only arguments
                 render_kw_only_separator = False
             elif kind == _KEYWORD_ONLY and render_kw_only_separator:
                 # We have a keyword-only parameter to render and we haven't
                 # rendered an '*args'-like parameter before, so add a '*'
                 # separator to the parameters list ("foo(arg1, *, arg2)" case)
                 result.append('*')
                 # This condition should be only triggered once, so
                 # reset the flag
                 render_kw_only_separator = False
 
             result.append(formatted)
 
         rendered = '({0})'.format(', '.join(result))
 
         if self.return_annotation is not _empty:
             anno = formatannotation(self.return_annotation)
             rendered += ' -> {0}'.format(anno)
 
         return rendered

docs/source/config/index.rst

@@ -1,30 +1,31 b''
 .. _config_index:
 
 ===============================
 Configuration and customization
 ===============================
 
 Configuring IPython
 -------------------
 
 .. toctree::
    :maxdepth: 2
 
    intro
    options/index
    details
 
 .. seealso::
 
    :doc:`/development/config`
       Technical details of the config system.
 
 Extending and integrating with IPython
 --------------------------------------
 
 .. toctree::
    :maxdepth: 2
 
    extensions/index
    integrating
    inputtransforms
+   callbacks

setup.py

@@ -1,339 +1,343 b''
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 """Setup script for IPython.
 
 Under Posix environments it works like a typical setup.py script.
 Under Windows, the command sdist is not supported, since IPython
 requires utilities which are not available under Windows."""
 
 #-----------------------------------------------------------------------------
 #  Copyright (c) 2008-2011, IPython Development Team.
 #  Copyright (c) 2001-2007, Fernando Perez <[e-mail]>
 #  Copyright (c) 2001, Janko Hauser <[e-mail]>
 #  Copyright (c) 2001, Nathaniel Gray <[e-mail]>
 #
 #  Distributed under the terms of the Modified BSD License.
 #
 #  The full license is in the file COPYING.txt, distributed with this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Minimal Python version sanity check
 #-----------------------------------------------------------------------------
 from __future__ import print_function
 
 import sys
 
 # This check is also made in IPython/__init__, don't forget to update both when
 # changing Python version requirements.
 if sys.version_info[:2] < (2,7):
     error = "ERROR: IPython requires Python Version 2.7 or above."
     print(error, file=sys.stderr)
     sys.exit(1)
 
 PY3 = (sys.version_info[0] >= 3)
 
 # At least we're on the python version we need, move on.
 
 #-------------------------------------------------------------------------------
 # Imports
 #-------------------------------------------------------------------------------
 
 # Stdlib imports
 import os
 import shutil
 
 from glob import glob
 
 # BEFORE importing distutils, remove MANIFEST. distutils doesn't properly
 # update it when the contents of directories change.
 if os.path.exists('MANIFEST'): os.remove('MANIFEST')
 
 from distutils.core import setup
 
 # Our own imports
 from setupbase import target_update
 
 from setupbase import (
     setup_args,
     find_packages,
     find_package_data,
     check_package_data_first,
     find_entry_points,
     build_scripts_entrypt,
     find_data_files,
     check_for_dependencies,
     git_prebuild,
     check_submodule_status,
     update_submodules,
     require_submodules,
     UpdateSubmodules,
     get_bdist_wheel,
     CompileCSS,
     JavascriptVersion,
     install_symlinked,
     install_lib_symlink,
     install_scripts_for_symlink,
     unsymlink,
 )
 from setupext import setupext
 
 isfile = os.path.isfile
 pjoin = os.path.join
 
 #-----------------------------------------------------------------------------
 # Function definitions
 #-----------------------------------------------------------------------------
 
 def cleanup():
     """Clean up the junk left around by the build process"""
     if "develop" not in sys.argv and "egg_info" not in sys.argv:
         try:
             shutil.rmtree('ipython.egg-info')
         except:
             try:
                 os.unlink('ipython.egg-info')
             except:
                 pass
 
 #-------------------------------------------------------------------------------
 # Handle OS specific things
 #-------------------------------------------------------------------------------
 
 if os.name in ('nt','dos'):
     os_name = 'windows'
 else:
     os_name = os.name
 
 # Under Windows, 'sdist' has not been supported.  Now that the docs build with
 # Sphinx it might work, but let's not turn it on until someone confirms that it
 # actually works.
 if os_name == 'windows' and 'sdist' in sys.argv:
     print('The sdist command is not available under Windows.  Exiting.')
     sys.exit(1)
 
 #-------------------------------------------------------------------------------
 # Make sure we aren't trying to run without submodules
 #-------------------------------------------------------------------------------
 here = os.path.abspath(os.path.dirname(__file__))
 
 def require_clean_submodules():
     """Check on git submodules before distutils can do anything
 
     Since distutils cannot be trusted to update the tree
     after everything has been set in motion,
     this is not a distutils command.
     """
     # PACKAGERS: Add a return here to skip checks for git submodules
     
     # don't do anything if nothing is actually supposed to happen
     for do_nothing in ('-h', '--help', '--help-commands', 'clean', 'submodule'):
         if do_nothing in sys.argv:
             return
 
     status = check_submodule_status(here)
 
     if status == "missing":
         print("checking out submodules for the first time")
         update_submodules(here)
     elif status == "unclean":
         print('\n'.join([
             "Cannot build / install IPython with unclean submodules",
             "Please update submodules with",
             "    python setup.py submodule",
             "or",
             "    git submodule update",
             "or commit any submodule changes you have made."
         ]))
         sys.exit(1)
 
 require_clean_submodules()
 
 #-------------------------------------------------------------------------------
 # Things related to the IPython documentation
 #-------------------------------------------------------------------------------
 
 # update the manuals when building a source dist
 if len(sys.argv) >= 2 and sys.argv[1] in ('sdist','bdist_rpm'):
 
     # List of things to be updated. Each entry is a triplet of args for
     # target_update()
     to_update = [
                   # FIXME - Disabled for now: we need to redo an automatic way
                   # of generating the magic info inside the rst.
                   #('docs/magic.tex',
                   #['IPython/Magic.py'],
                   #"cd doc && ./update_magic.sh" ),
 
                  ('docs/man/ipcluster.1.gz',
                   ['docs/man/ipcluster.1'],
                   'cd docs/man && gzip -9c ipcluster.1 > ipcluster.1.gz'),
 
                  ('docs/man/ipcontroller.1.gz',
                   ['docs/man/ipcontroller.1'],
                   'cd docs/man && gzip -9c ipcontroller.1 > ipcontroller.1.gz'),
 
                  ('docs/man/ipengine.1.gz',
                   ['docs/man/ipengine.1'],
                   'cd docs/man && gzip -9c ipengine.1 > ipengine.1.gz'),
 
                  ('docs/man/ipython.1.gz',
                   ['docs/man/ipython.1'],
                   'cd docs/man && gzip -9c ipython.1 > ipython.1.gz'),
 
                  ]
 
 
     [ target_update(*t) for t in to_update ]
 
 #---------------------------------------------------------------------------
 # Find all the packages, package data, and data_files
 #---------------------------------------------------------------------------
 
 packages = find_packages()
 package_data = find_package_data()
 
 data_files = find_data_files()
 
 setup_args['packages'] = packages
 setup_args['package_data'] = package_data
 setup_args['data_files'] = data_files
 
 #---------------------------------------------------------------------------
 # custom distutils commands
 #---------------------------------------------------------------------------
 # imports here, so they are after setuptools import if there was one
 from distutils.command.sdist import sdist
 from distutils.command.upload import upload
 
 class UploadWindowsInstallers(upload):
 
     description = "Upload Windows installers to PyPI (only used from tools/release_windows.py)"
     user_options = upload.user_options + [
         ('files=', 'f', 'exe file (or glob) to upload')
     ]
     def initialize_options(self):
         upload.initialize_options(self)
         meta = self.distribution.metadata
         base = '{name}-{version}'.format(
             name=meta.get_name(),
             version=meta.get_version()
         )
         self.files = os.path.join('dist', '%s.*.exe' % base)
 
     def run(self):
         for dist_file in glob(self.files):
             self.upload_file('bdist_wininst', 'any', dist_file)
 
 setup_args['cmdclass'] = {
     'build_py': check_package_data_first(git_prebuild('IPython')),
     'sdist' : git_prebuild('IPython', sdist),
     'upload_wininst' : UploadWindowsInstallers,
     'submodule' : UpdateSubmodules,
     'css' : CompileCSS,
     'symlink': install_symlinked,
     'install_lib_symlink': install_lib_symlink,
     'install_scripts_sym': install_scripts_for_symlink,
     'unsymlink': unsymlink,
     'jsversion' : JavascriptVersion,
 }
 
 #---------------------------------------------------------------------------
 # Handle scripts, dependencies, and setuptools specific things
 #---------------------------------------------------------------------------
 
 # For some commands, use setuptools.  Note that we do NOT list install here!
 # If you want a setuptools-enhanced install, just run 'setupegg.py install'
 needs_setuptools = set(('develop', 'release', 'bdist_egg', 'bdist_rpm',
            'bdist', 'bdist_dumb', 'bdist_wininst', 'bdist_wheel',
            'egg_info', 'easy_install', 'upload', 'install_egg_info',
             ))
 if sys.platform == 'win32':
     # Depend on setuptools for install on *Windows only*
     # If we get script-installation working without setuptools,
     # then we can back off, but until then use it.
     # See Issue #369 on GitHub for more
     needs_setuptools.add('install')
 
 if len(needs_setuptools.intersection(sys.argv)) > 0:
     import setuptools
 
 # This dict is used for passing extra arguments that are setuptools
 # specific to setup
 setuptools_extra_args = {}
 
 # setuptools requirements
 
 extras_require = dict(
     parallel = ['pyzmq>=2.1.11'],
     qtconsole = ['pyzmq>=2.1.11', 'pygments'],
     zmq = ['pyzmq>=2.1.11'],
     doc = ['Sphinx>=1.1', 'numpydoc'],
     test = ['nose>=0.10.1'],
     notebook = ['tornado>=3.1', 'pyzmq>=2.1.11', 'jinja2'],
     nbconvert = ['pygments', 'jinja2', 'Sphinx>=0.3']
 )
+if sys.version_info < (3, 3):
+    extras_require['test'].append('mock')
+
 everything = set()
 for deps in extras_require.values():
     everything.update(deps)
 extras_require['all'] = everything
+
 install_requires = []
 if sys.platform == 'darwin':
     if any(arg.startswith('bdist') for arg in sys.argv) or not setupext.check_for_readline():
         install_requires.append('gnureadline')
 elif sys.platform.startswith('win'):
     # Pyreadline has unicode and Python 3 fixes in 2.0
     install_requires.append('pyreadline>=2.0')
 
 if 'setuptools' in sys.modules:
     # setup.py develop should check for submodules
     from setuptools.command.develop import develop
     setup_args['cmdclass']['develop'] = require_submodules(develop)
     setup_args['cmdclass']['bdist_wheel'] = get_bdist_wheel()
     
     setuptools_extra_args['zip_safe'] = False
     setuptools_extra_args['entry_points'] = {'console_scripts':find_entry_points()}
     setup_args['extras_require'] = extras_require
     requires = setup_args['install_requires'] = install_requires
 
     # Script to be run by the windows binary installer after the default setup
     # routine, to add shortcuts and similar windows-only things.  Windows
     # post-install scripts MUST reside in the scripts/ dir, otherwise distutils
     # doesn't find them.
     if 'bdist_wininst' in sys.argv:
         if len(sys.argv) > 2 and \
                ('sdist' in sys.argv or 'bdist_rpm' in sys.argv):
             print >> sys.stderr, "ERROR: bdist_wininst must be run alone. Exiting."
             sys.exit(1)
         setup_args['data_files'].append(
             ['Scripts', ('scripts/ipython.ico', 'scripts/ipython_nb.ico')])
         setup_args['scripts'] = [pjoin('scripts','ipython_win_post_install.py')]
         setup_args['options'] = {"bdist_wininst":
                                  {"install_script":
                                   "ipython_win_post_install.py"}}
 
 else:
     # If we are installing without setuptools, call this function which will
     # check for dependencies an inform the user what is needed.  This is
     # just to make life easy for users.
     for install_cmd in ('install', 'symlink'):
         if install_cmd in sys.argv:
             check_for_dependencies()
             break
     # scripts has to be a non-empty list, or install_scripts isn't called
     setup_args['scripts'] = [e.split('=')[0].strip() for e in find_entry_points()]
 
     setup_args['cmdclass']['build_scripts'] = build_scripts_entrypt
 
 #---------------------------------------------------------------------------
 # Do the actual setup now
 #---------------------------------------------------------------------------
 
 setup_args.update(setuptools_extra_args)
 
 def main():
     setup(**setup_args)
     cleanup()
 
 if __name__ == '__main__':
     main()

setupbase.py

@@ -1,695 +1,696 b''
 # encoding: utf-8
 """
 This module defines the things that are used in setup.py for building IPython
 
 This includes:
 
     * The basic arguments to setup
     * Functions for finding things like packages, package data, etc.
     * A function for checking dependencies.
 """
 from __future__ import print_function
 
 #-------------------------------------------------------------------------------
 #  Copyright (C) 2008  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
 #-------------------------------------------------------------------------------
 import errno
 import os
 import sys
 
 from distutils.command.build_py import build_py
 from distutils.command.build_scripts import build_scripts
 from distutils.command.install import install
 from distutils.command.install_scripts import install_scripts
 from distutils.cmd import Command
 from glob import glob
 from subprocess import call
 
 from setupext import install_data_ext
 
 #-------------------------------------------------------------------------------
 # Useful globals and utility functions
 #-------------------------------------------------------------------------------
 
 # A few handy globals
 isfile = os.path.isfile
 pjoin = os.path.join
 repo_root = os.path.dirname(os.path.abspath(__file__))
 
 def oscmd(s):
     print(">", s)
     os.system(s)
 
 # Py3 compatibility hacks, without assuming IPython itself is installed with
 # the full py3compat machinery.
 
 try:
     execfile
 except NameError:
     def execfile(fname, globs, locs=None):
         locs = locs or globs
         exec(compile(open(fname).read(), fname, "exec"), globs, locs)
 
 # A little utility we'll need below, since glob() does NOT allow you to do
 # exclusion on multiple endings!
 def file_doesnt_endwith(test,endings):
     """Return true if test is a file and its name does NOT end with any
     of the strings listed in endings."""
     if not isfile(test):
         return False
     for e in endings:
         if test.endswith(e):
             return False
     return True
 
 #---------------------------------------------------------------------------
 # Basic project information
 #---------------------------------------------------------------------------
 
 # release.py contains version, authors, license, url, keywords, etc.
 execfile(pjoin(repo_root, 'IPython','core','release.py'), globals())
 
 # Create a dict with the basic information
 # This dict is eventually passed to setup after additional keys are added.
 setup_args = dict(
       name             = name,
       version          = version,
       description      = description,
       long_description = long_description,
       author           = author,
       author_email     = author_email,
       url              = url,
       download_url     = download_url,
       license          = license,
       platforms        = platforms,
       keywords         = keywords,
       classifiers      = classifiers,
       cmdclass         = {'install_data': install_data_ext},
       )
 
 
 #---------------------------------------------------------------------------
 # Find packages
 #---------------------------------------------------------------------------
 
 def find_packages():
     """
     Find all of IPython's packages.
     """
     excludes = ['deathrow', 'quarantine']
     packages = []
     for dir,subdirs,files in os.walk('IPython'):
         package = dir.replace(os.path.sep, '.')
         if any(package.startswith('IPython.'+exc) for exc in excludes):
             # package is to be excluded (e.g. deathrow)
             continue
         if '__init__.py' not in files:
             # not a package
             continue
         packages.append(package)
     return packages
 
 #---------------------------------------------------------------------------
 # Find package data
 #---------------------------------------------------------------------------
 
 def find_package_data():
     """
     Find IPython's package_data.
     """
     # This is not enough for these things to appear in an sdist.
     # We need to muck with the MANIFEST to get this to work
     
     # exclude components from the walk,
     # we will build the components separately
     excludes = ['components']
     
     # add 'static/' prefix to exclusions, and tuplify for use in startswith
     excludes = tuple([pjoin('static', ex) for ex in excludes])
     
     # walk notebook resources:
     cwd = os.getcwd()
     os.chdir(os.path.join('IPython', 'html'))
     static_data = []
     for parent, dirs, files in os.walk('static'):
         if parent.startswith(excludes):
             continue
         for f in files:
             static_data.append(pjoin(parent, f))
     components = pjoin("static", "components")
     # select the components we actually need to install
     # (there are lots of resources we bundle for sdist-reasons that we don't actually use)
     static_data.extend([
         pjoin(components, "backbone", "backbone-min.js"),
         pjoin(components, "bootstrap", "bootstrap", "js", "bootstrap.min.js"),
         pjoin(components, "font-awesome", "font", "*.*"),
         pjoin(components, "highlight.js", "build", "highlight.pack.js"),
         pjoin(components, "jquery", "jquery.min.js"),
         pjoin(components, "jquery-ui", "ui", "minified", "jquery-ui.min.js"),
         pjoin(components, "jquery-ui", "themes", "smoothness", "jquery-ui.min.css"),
         pjoin(components, "marked", "lib", "marked.js"),
         pjoin(components, "requirejs", "require.js"),
         pjoin(components, "underscore", "underscore-min.js"),
     ])
     
     # Ship all of Codemirror's CSS and JS
     for parent, dirs, files in os.walk(pjoin(components, 'codemirror')):
         for f in files:
             if f.endswith(('.js', '.css')):
                 static_data.append(pjoin(parent, f))
     
     os.chdir(os.path.join('tests',))
     js_tests = glob('*.js') + glob('*/*.js')
 
     os.chdir(os.path.join(cwd, 'IPython', 'nbconvert'))
     nbconvert_templates = [os.path.join(dirpath, '*.*')
                             for dirpath, _, _ in os.walk('templates')]
 
     os.chdir(cwd)
 
     package_data = {
         'IPython.config.profile' : ['README*', '*/*.py'],
         'IPython.core.tests' : ['*.png', '*.jpg'],
         'IPython.lib.tests' : ['*.wav'],
         'IPython.testing.plugin' : ['*.txt'],
         'IPython.html' : ['templates/*'] + static_data,
         'IPython.html.tests' : js_tests,
         'IPython.qt.console' : ['resources/icon/*.svg'],
         'IPython.nbconvert' : nbconvert_templates +
             ['tests/files/*.*', 'exporters/tests/files/*.*'],
         'IPython.nbconvert.filters' : ['marked.js'],
         'IPython.nbformat' : ['tests/*.ipynb']
     }
     
     return package_data
 
 
 def check_package_data(package_data):
     """verify that package_data globs make sense"""
     print("checking package data")
     for pkg, data in package_data.items():
         pkg_root = pjoin(*pkg.split('.'))
         for d in data:
             path = pjoin(pkg_root, d)
             if '*' in path:
                 assert len(glob(path)) > 0, "No files match pattern %s" % path
             else:
                 assert os.path.exists(path), "Missing package data: %s" % path
 
 
 def check_package_data_first(command):
     """decorator for checking package_data before running a given command
     
     Probably only needs to wrap build_py
     """
     class DecoratedCommand(command):
         def run(self):
             check_package_data(self.package_data)
             command.run(self)
     return DecoratedCommand
 
 
 #---------------------------------------------------------------------------
 # Find data files
 #---------------------------------------------------------------------------
 
 def make_dir_struct(tag,base,out_base):
     """Make the directory structure of all files below a starting dir.
 
     This is just a convenience routine to help build a nested directory
     hierarchy because distutils is too stupid to do this by itself.
 
     XXX - this needs a proper docstring!
     """
 
     # we'll use these a lot below
     lbase = len(base)
     pathsep = os.path.sep
     lpathsep = len(pathsep)
 
     out = []
     for (dirpath,dirnames,filenames) in os.walk(base):
         # we need to strip out the dirpath from the base to map it to the
         # output (installation) path.  This requires possibly stripping the
         # path separator, because otherwise pjoin will not work correctly
         # (pjoin('foo/','/bar') returns '/bar').
 
         dp_eff = dirpath[lbase:]
         if dp_eff.startswith(pathsep):
             dp_eff = dp_eff[lpathsep:]
         # The output path must be anchored at the out_base marker
         out_path = pjoin(out_base,dp_eff)
         # Now we can generate the final filenames. Since os.walk only produces
         # filenames, we must join back with the dirpath to get full valid file
         # paths:
         pfiles = [pjoin(dirpath,f) for f in filenames]
         # Finally, generate the entry we need, which is a pari of (output
         # path, files) for use as a data_files parameter in install_data.
         out.append((out_path, pfiles))
 
     return out
 
 
 def find_data_files():
     """
     Find IPython's data_files.
 
     Just man pages at this point.
     """
 
     manpagebase = pjoin('share', 'man', 'man1')
 
     # Simple file lists can be made by hand
     manpages = [f for f in glob(pjoin('docs','man','*.1.gz')) if isfile(f)]
     if not manpages:
         # When running from a source tree, the manpages aren't gzipped
         manpages = [f for f in glob(pjoin('docs','man','*.1')) if isfile(f)]
 
     # And assemble the entire output list
     data_files = [ (manpagebase, manpages) ]
 
     return data_files
 
 
 def make_man_update_target(manpage):
     """Return a target_update-compliant tuple for the given manpage.
 
     Parameters
     ----------
     manpage : string
       Name of the manpage, must include the section number (trailing number).
 
     Example
     -------
 
     >>> make_man_update_target('ipython.1') #doctest: +NORMALIZE_WHITESPACE
     ('docs/man/ipython.1.gz',
      ['docs/man/ipython.1'],
      'cd docs/man && gzip -9c ipython.1 > ipython.1.gz')
     """
     man_dir = pjoin('docs', 'man')
     manpage_gz = manpage + '.gz'
     manpath = pjoin(man_dir, manpage)
     manpath_gz = pjoin(man_dir, manpage_gz)
     gz_cmd = ( "cd %(man_dir)s && gzip -9c %(manpage)s > %(manpage_gz)s" %
                locals() )
     return (manpath_gz, [manpath], gz_cmd)
 
 # The two functions below are copied from IPython.utils.path, so we don't need
 # to import IPython during setup, which fails on Python 3.
 
 def target_outdated(target,deps):
     """Determine whether a target is out of date.
 
     target_outdated(target,deps) -> 1/0
 
     deps: list of filenames which MUST exist.
     target: single filename which may or may not exist.
 
     If target doesn't exist or is older than any file listed in deps, return
     true, otherwise return false.
     """
     try:
         target_time = os.path.getmtime(target)
     except os.error:
         return 1
     for dep in deps:
         dep_time = os.path.getmtime(dep)
         if dep_time > target_time:
             #print "For target",target,"Dep failed:",dep # dbg
             #print "times (dep,tar):",dep_time,target_time # dbg
             return 1
     return 0
 
 
 def target_update(target,deps,cmd):
     """Update a target with a given command given a list of dependencies.
 
     target_update(target,deps,cmd) -> runs cmd if target is outdated.
 
     This is just a wrapper around target_outdated() which calls the given
     command if target is outdated."""
 
     if target_outdated(target,deps):
         os.system(cmd)
 
 #---------------------------------------------------------------------------
 # Find scripts
 #---------------------------------------------------------------------------
 
 def find_entry_points():
     """Find IPython's scripts.
 
     if entry_points is True:
         return setuptools entry_point-style definitions
     else:
         return file paths of plain scripts [default]
 
     suffix is appended to script names if entry_points is True, so that the
     Python 3 scripts get named "ipython3" etc.
     """
     ep = [
             'ipython%s = IPython:start_ipython',
             'ipcontroller%s = IPython.parallel.apps.ipcontrollerapp:launch_new_instance',
             'ipengine%s = IPython.parallel.apps.ipengineapp:launch_new_instance',
             'ipcluster%s = IPython.parallel.apps.ipclusterapp:launch_new_instance',
             'iptest%s = IPython.testing.iptestcontroller:main',
         ]
     suffix = str(sys.version_info[0])
     return [e % '' for e in ep] + [e % suffix for e in ep]
 
 script_src = """#!{executable}
 # This script was automatically generated by setup.py
 if __name__ == '__main__':
     from {mod} import {func}
     {func}()
 """
 
 class build_scripts_entrypt(build_scripts):
     def run(self):
         self.mkpath(self.build_dir)
         outfiles = []
         for script in find_entry_points():
             name, entrypt = script.split('=')
             name = name.strip()
             entrypt = entrypt.strip()
             outfile = os.path.join(self.build_dir, name)
             outfiles.append(outfile)
             print('Writing script to', outfile)
 
             mod, func = entrypt.split(':')
             with open(outfile, 'w') as f:
                 f.write(script_src.format(executable=sys.executable,
                                           mod=mod, func=func))
 
         return outfiles, outfiles
 
 class install_lib_symlink(Command):
     user_options = [
         ('install-dir=', 'd', "directory to install to"),
         ]
 
     def initialize_options(self):
         self.install_dir = None
 
     def finalize_options(self):
         self.set_undefined_options('symlink',
                                    ('install_lib', 'install_dir'),
                                   )
 
     def run(self):
         if sys.platform == 'win32':
             raise Exception("This doesn't work on Windows.")
         pkg = os.path.join(os.getcwd(), 'IPython')
         dest = os.path.join(self.install_dir, 'IPython')
         if os.path.islink(dest):
             print('removing existing symlink at %s' % dest)
             os.unlink(dest)
         print('symlinking %s -> %s' % (pkg, dest))
         os.symlink(pkg, dest)
 
 class unsymlink(install):
     def run(self):
         dest = os.path.join(self.install_lib, 'IPython')
         if os.path.islink(dest):
             print('removing symlink at %s' % dest)
             os.unlink(dest)
         else:
             print('No symlink exists at %s' % dest)
 
 class install_symlinked(install):
     def run(self):
         if sys.platform == 'win32':
             raise Exception("This doesn't work on Windows.")
 
         # Run all sub-commands (at least those that need to be run)
         for cmd_name in self.get_sub_commands():
             self.run_command(cmd_name)
     
     # 'sub_commands': a list of commands this command might have to run to
     # get its work done.  See cmd.py for more info.
     sub_commands = [('install_lib_symlink', lambda self:True),
                     ('install_scripts_sym', lambda self:True),
                    ]
 
 class install_scripts_for_symlink(install_scripts):
     """Redefined to get options from 'symlink' instead of 'install'.
     
     I love distutils almost as much as I love setuptools.
     """
     def finalize_options(self):
         self.set_undefined_options('build', ('build_scripts', 'build_dir'))
         self.set_undefined_options('symlink',
                                    ('install_scripts', 'install_dir'),
                                    ('force', 'force'),
                                    ('skip_build', 'skip_build'),
                                   )
 
 #---------------------------------------------------------------------------
 # Verify all dependencies
 #---------------------------------------------------------------------------
 
 def check_for_dependencies():
     """Check for IPython's dependencies.
 
     This function should NOT be called if running under setuptools!
     """
     from setupext.setupext import (
         print_line, print_raw, print_status,
         check_for_sphinx, check_for_pygments,
         check_for_nose, check_for_pexpect,
         check_for_pyzmq, check_for_readline,
         check_for_jinja2, check_for_tornado
     )
     print_line()
     print_raw("BUILDING IPYTHON")
     print_status('python', sys.version)
     print_status('platform', sys.platform)
     if sys.platform == 'win32':
         print_status('Windows version', sys.getwindowsversion())
 
     print_raw("")
     print_raw("OPTIONAL DEPENDENCIES")
 
     check_for_sphinx()
     check_for_pygments()
     check_for_nose()
     if os.name == 'posix':
         check_for_pexpect()
     check_for_pyzmq()
     check_for_tornado()
     check_for_readline()
     check_for_jinja2()
 
 #---------------------------------------------------------------------------
 # VCS related
 #---------------------------------------------------------------------------
 
 # utils.submodule has checks for submodule status
 execfile(pjoin('IPython','utils','submodule.py'), globals())
 
 class UpdateSubmodules(Command):
     """Update git submodules
     
     IPython's external javascript dependencies live in a separate repo.
     """
     description = "Update git submodules"
     user_options = []
     
     def initialize_options(self):
         pass
     
     def finalize_options(self):
         pass
     
     def run(self):
         failure = False
         try:
             self.spawn('git submodule init'.split())
             self.spawn('git submodule update --recursive'.split())
         except Exception as e:
             failure = e
             print(e)
         
         if not check_submodule_status(repo_root) == 'clean':
             print("submodules could not be checked out")
             sys.exit(1)
 
 
 def git_prebuild(pkg_dir, build_cmd=build_py):
     """Return extended build or sdist command class for recording commit
     
     records git commit in IPython.utils._sysinfo.commit
     
     for use in IPython.utils.sysinfo.sys_info() calls after installation.
     
     Also ensures that submodules exist prior to running
     """
     
     class MyBuildPy(build_cmd):
         ''' Subclass to write commit data into installation tree '''
         def run(self):
             build_cmd.run(self)
             # this one will only fire for build commands
             if hasattr(self, 'build_lib'):
                 self._record_commit(self.build_lib)
         
         def make_release_tree(self, base_dir, files):
             # this one will fire for sdist
             build_cmd.make_release_tree(self, base_dir, files)
             self._record_commit(base_dir)
         
         def _record_commit(self, base_dir):
             import subprocess
             proc = subprocess.Popen('git rev-parse --short HEAD',
                                     stdout=subprocess.PIPE,
                                     stderr=subprocess.PIPE,
                                     shell=True)
             repo_commit, _ = proc.communicate()
             repo_commit = repo_commit.strip().decode("ascii")
             
             out_pth = pjoin(base_dir, pkg_dir, 'utils', '_sysinfo.py')
             if os.path.isfile(out_pth) and not repo_commit:
                 # nothing to write, don't clobber
                 return
             
             print("writing git commit '%s' to %s" % (repo_commit, out_pth))
             
             # remove to avoid overwriting original via hard link
             try:
                 os.remove(out_pth)
             except (IOError, OSError):
                 pass
             with open(out_pth, 'w') as out_file:
                 out_file.writelines([
                     '# GENERATED BY setup.py\n',
                     'commit = "%s"\n' % repo_commit,
                 ])
     return require_submodules(MyBuildPy)
 
 
 def require_submodules(command):
     """decorator for instructing a command to check for submodules before running"""
     class DecoratedCommand(command):
         def run(self):
             if not check_submodule_status(repo_root) == 'clean':
                 print("submodules missing! Run `setup.py submodule` and try again")
                 sys.exit(1)
             command.run(self)
     return DecoratedCommand
 
 #---------------------------------------------------------------------------
 # bdist related
 #---------------------------------------------------------------------------
 
 def get_bdist_wheel():
     """Construct bdist_wheel command for building wheels
     
     Constructs py2-none-any tag, instead of py2.7-none-any
     """
     class RequiresWheel(Command):
         description = "Dummy command for missing bdist_wheel"
         user_options = []
 
         def initialize_options(self):
             pass
 
         def finalize_options(self):
             pass
 
         def run(self):
             print("bdist_wheel requires the wheel package")
             sys.exit(1)
 
     if 'setuptools' not in sys.modules:
         return RequiresWheel
     else:
         try:
             from wheel.bdist_wheel import bdist_wheel, read_pkg_info, write_pkg_info
         except ImportError:
             return RequiresWheel
         
         class bdist_wheel_tag(bdist_wheel):
 
             def get_tag(self):
                 return ('py%i' % sys.version_info[0], 'none', 'any')
 
             def add_requirements(self, metadata_path):
                 """transform platform-dependent requirements"""
                 pkg_info = read_pkg_info(metadata_path)
                 # pkg_info is an email.Message object (?!)
                 # we have to remove the unconditional 'readline' and/or 'pyreadline' entries
                 # and transform them to conditionals
                 requires = pkg_info.get_all('Requires-Dist')
                 del pkg_info['Requires-Dist']
                 def _remove_startswith(lis, prefix):
                     """like list.remove, but with startswith instead of =="""
                     found = False
                     for idx, item in enumerate(lis):
                         if item.startswith(prefix):
                             found = True
                             break
                     if found:
                         lis.pop(idx)
                 
-                for pkg in ("gnureadline", "pyreadline"):
+                for pkg in ("gnureadline", "pyreadline", "mock"):
                     _remove_startswith(requires, pkg)
                 requires.append("gnureadline; sys.platform == 'darwin' and platform.python_implementation == 'CPython'")
                 requires.append("pyreadline (>=2.0); sys.platform == 'win32' and platform.python_implementation == 'CPython'")
+                requires.append("mock; extra == 'test' and python_version < '3.3'")
                 for r in requires:
                     pkg_info['Requires-Dist'] = r
                 write_pkg_info(metadata_path, pkg_info)
         
         return bdist_wheel_tag
 
 #---------------------------------------------------------------------------
 # Notebook related
 #---------------------------------------------------------------------------
 
 class CompileCSS(Command):
     """Recompile Notebook CSS
     
     Regenerate the compiled CSS from LESS sources.
     
     Requires various dev dependencies, such as fabric and lessc.
     """
     description = "Recompile Notebook CSS"
     user_options = []
     
     def initialize_options(self):
         pass
     
     def finalize_options(self):
         pass
     
     def run(self):
         call("fab css", shell=True, cwd=pjoin(repo_root, "IPython", "html"))
 
 class JavascriptVersion(Command):
     """write the javascript version to notebook javascript"""
     description = "Write IPython version to javascript"
     user_options = []
     
     def initialize_options(self):
         pass
     
     def finalize_options(self):
         pass
     
     def run(self):
         nsfile = pjoin(repo_root, "IPython", "html", "static", "base", "js", "namespace.js")
         with open(nsfile) as f:
             lines = f.readlines()
         with open(nsfile, 'w') as f:
             for line in lines:
                 if line.startswith("IPython.version"):
                     line = 'IPython.version = "{0}";\n'.format(version)
                 f.write(line)
             

tox.ini

@@ -1,24 +1,25 b''
 # Tox (http://tox.testrun.org/) is a tool for running tests
 # in multiple virtualenvs. This configuration file will run the
 # test suite on all supported python versions. To use it, "pip install tox"
 # and then run "tox" from this directory.
 
 [tox]
 envlist = py27, py33
 
 [testenv]
 deps = 
   nose
+  mock
   tornado
   jinja2
   sphinx
   pygments
 # To avoid loading IPython module in the current directory, change
 # current directory to ".tox/py*/tmp" before running test.
 changedir = {envtmpdir}
 
 commands =
     # As pip does not treat egg, use easy_install to install PyZMQ.
     # See also: https://github.com/zeromq/pyzmq
     easy_install -q pyzmq
     iptest --all