adopt traitlets 4.2 API

- `.tag(config=True)`
- `@default`
- `@observe`

IPython/core/alias.py

@@ -1,257 +1,257 b''
 # encoding: utf-8
 """
 System command aliases.
 
 Authors:
 
 * Fernando Perez
 * Brian Granger
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2011  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.
 #
 #  The full license is in the file COPYING.txt, distributed with this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import os
 import re
 import sys
 
 from traitlets.config.configurable import Configurable
 from IPython.core.error import UsageError
 
 from IPython.utils.py3compat import string_types
 from traitlets import List, Instance
 from logging import error
 
 #-----------------------------------------------------------------------------
 # Utilities
 #-----------------------------------------------------------------------------
 
 # This is used as the pattern for calls to split_user_input.
 shell_line_split = re.compile(r'^(\s*)()(\S+)(.*$)')
 
 def default_aliases():
     """Return list of shell aliases to auto-define.
     """
     # Note: the aliases defined here should be safe to use on a kernel
     # regardless of what frontend it is attached to.  Frontends that use a
     # kernel in-process can define additional aliases that will only work in
     # their case.  For example, things like 'less' or 'clear' that manipulate
     # the terminal should NOT be declared here, as they will only work if the
     # kernel is running inside a true terminal, and not over the network.
 
     if os.name == 'posix':
         default_aliases = [('mkdir', 'mkdir'), ('rmdir', 'rmdir'),
                            ('mv', 'mv'), ('rm', 'rm'), ('cp', 'cp'),
                            ('cat', 'cat'),
                            ]
         # Useful set of ls aliases.  The GNU and BSD options are a little
         # different, so we make aliases that provide as similar as possible
         # behavior in ipython, by passing the right flags for each platform
         if sys.platform.startswith('linux'):
             ls_aliases = [('ls', 'ls -F --color'),
                           # long ls
                           ('ll', 'ls -F -o --color'),
                           # ls normal files only
                           ('lf', 'ls -F -o --color %l | grep ^-'),
                           # ls symbolic links
                           ('lk', 'ls -F -o --color %l | grep ^l'),
                           # directories or links to directories,
                           ('ldir', 'ls -F -o --color %l | grep /$'),
                           # things which are executable
                           ('lx', 'ls -F -o --color %l | grep ^-..x'),
                           ]
         elif sys.platform.startswith('openbsd') or sys.platform.startswith('netbsd'):
             # OpenBSD, NetBSD. The ls implementation on these platforms do not support
             # the -G switch and lack the ability to use colorized output.
             ls_aliases = [('ls', 'ls -F'),
                           # long ls
                           ('ll', 'ls -F -l'),
                           # ls normal files only
                           ('lf', 'ls -F -l %l | grep ^-'),
                           # ls symbolic links
                           ('lk', 'ls -F -l %l | grep ^l'),
                           # directories or links to directories,
                           ('ldir', 'ls -F -l %l | grep /$'),
                           # things which are executable
                           ('lx', 'ls -F -l %l | grep ^-..x'),
                           ]
         else:
             # BSD, OSX, etc.
             ls_aliases = [('ls', 'ls -F -G'),
                           # long ls
                           ('ll', 'ls -F -l -G'),
                           # ls normal files only
                           ('lf', 'ls -F -l -G %l | grep ^-'),
                           # ls symbolic links
                           ('lk', 'ls -F -l -G %l | grep ^l'),
                           # directories or links to directories,
                           ('ldir', 'ls -F -G -l %l | grep /$'),
                           # things which are executable
                           ('lx', 'ls -F -l -G %l | grep ^-..x'),
                           ]
         default_aliases = default_aliases + ls_aliases
     elif os.name in ['nt', 'dos']:
         default_aliases = [('ls', 'dir /on'),
                            ('ddir', 'dir /ad /on'), ('ldir', 'dir /ad /on'),
                            ('mkdir', 'mkdir'), ('rmdir', 'rmdir'),
                            ('echo', 'echo'), ('ren', 'ren'), ('copy', 'copy'),
                            ]
     else:
         default_aliases = []
 
     return default_aliases
 
 
 class AliasError(Exception):
     pass
 
 
 class InvalidAliasError(AliasError):
     pass
 
 class Alias(object):
     """Callable object storing the details of one alias.
 
     Instances are registered as magic functions to allow use of aliases.
     """
 
     # Prepare blacklist
     blacklist = {'cd','popd','pushd','dhist','alias','unalias'}
 
     def __init__(self, shell, name, cmd):
         self.shell = shell
         self.name = name
         self.cmd = cmd
         self.__doc__ = "Alias for `!{}`".format(cmd)
         self.nargs = self.validate()
 
     def validate(self):
         """Validate the alias, and return the number of arguments."""
         if self.name in self.blacklist:
             raise InvalidAliasError("The name %s can't be aliased "
                                     "because it is a keyword or builtin." % self.name)
         try:
             caller = self.shell.magics_manager.magics['line'][self.name]
         except KeyError:
             pass
         else:
             if not isinstance(caller, Alias):
                 raise InvalidAliasError("The name %s can't be aliased "
                                         "because it is another magic command." % self.name)
 
         if not (isinstance(self.cmd, string_types)):
             raise InvalidAliasError("An alias command must be a string, "
                                     "got: %r" % self.cmd)
 
         nargs = self.cmd.count('%s') - self.cmd.count('%%s')
   
         if (nargs > 0) and (self.cmd.find('%l') >= 0):
             raise InvalidAliasError('The %s and %l specifiers are mutually '
                                     'exclusive in alias definitions.')
 
         return nargs
 
     def __repr__(self):
         return "<alias {} for {!r}>".format(self.name, self.cmd)
 
     def __call__(self, rest=''):
         cmd = self.cmd
         nargs = self.nargs
         # Expand the %l special to be the user's input line
         if cmd.find('%l') >= 0:
             cmd = cmd.replace('%l', rest)
             rest = ''
         
         if nargs==0:
             if cmd.find('%%s') >= 1:
                 cmd = cmd.replace('%%s', '%s')
             # Simple, argument-less aliases
             cmd = '%s %s' % (cmd, rest)
         else:
             # Handle aliases with positional arguments
             args = rest.split(None, nargs)
             if len(args) < nargs:
                 raise UsageError('Alias <%s> requires %s arguments, %s given.' %
                       (self.name, nargs, len(args)))
             cmd = '%s %s' % (cmd % tuple(args[:nargs]),' '.join(args[nargs:]))
 
         self.shell.system(cmd)
 
 #-----------------------------------------------------------------------------
 # Main AliasManager class
 #-----------------------------------------------------------------------------
 
 class AliasManager(Configurable):
 
-    default_aliases = List(default_aliases(), config=True)
-    user_aliases = List(default_value=[], config=True)
+    default_aliases = List(default_aliases()).tag(config=True)
+    user_aliases = List(default_value=[]).tag(config=True)
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
 
     def __init__(self, shell=None, **kwargs):
         super(AliasManager, self).__init__(shell=shell, **kwargs)
         # For convenient access
         self.linemagics = self.shell.magics_manager.magics['line']
         self.init_aliases()
 
     def init_aliases(self):
         # Load default & user aliases
         for name, cmd in self.default_aliases + self.user_aliases:
             self.soft_define_alias(name, cmd)
 
     @property
     def aliases(self):
         return [(n, func.cmd) for (n, func) in self.linemagics.items()
                             if isinstance(func, Alias)]
 
     def soft_define_alias(self, name, cmd):
         """Define an alias, but don't raise on an AliasError."""
         try:
             self.define_alias(name, cmd)
         except AliasError as e:
             error("Invalid alias: %s" % e)
 
     def define_alias(self, name, cmd):
         """Define a new alias after validating it.
 
         This will raise an :exc:`AliasError` if there are validation
         problems.
         """
         caller = Alias(shell=self.shell, name=name, cmd=cmd)
         self.shell.magics_manager.register_function(caller, magic_kind='line',
                                                     magic_name=name)
 
     def get_alias(self, name):
         """Return an alias, or None if no alias by that name exists."""
         aname = self.linemagics.get(name, None)
         return aname if isinstance(aname, Alias) else None
 
     def is_alias(self, name):
         """Return whether or not a given name has been defined as an alias"""
         return self.get_alias(name) is not None
 
     def undefine_alias(self, name):
         if self.is_alias(name):
             del self.linemagics[name]
         else:
             raise ValueError('%s is not an alias' % name)
 
     def clear_aliases(self):
         for name, cmd in self.aliases:
             self.undefine_alias(name)
 
     def retrieve_alias(self, name):
         """Retrieve the command to which an alias expands."""
         caller = self.get_alias(name)
         if caller:
             return caller.cmd
         else:
             raise ValueError('%s is not an alias' % name)

IPython/core/application.py

@@ -1,407 +1,428 b''
 # encoding: utf-8
 """
 An application for IPython.
 
 All top-level applications should use the classes in this module for
 handling configuration and creating configurables.
 
 The job of an :class:`Application` is to create the master configuration
 object and then create the configurable objects, passing the config to them.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import atexit
 import glob
 import logging
 import os
 import shutil
 import sys
 
 from traitlets.config.application import Application, catch_config_error
 from traitlets.config.loader import ConfigFileNotFound, PyFileConfigLoader
 from IPython.core import release, crashhandler
 from IPython.core.profiledir import ProfileDir, ProfileDirError
 from IPython.paths import get_ipython_dir, get_ipython_package_dir
 from IPython.utils.path import ensure_dir_exists
 from IPython.utils import py3compat
-from traitlets import List, Unicode, Type, Bool, Dict, Set, Instance, Undefined
+from traitlets import (
+    List, Unicode, Type, Bool, Dict, Set, Instance, Undefined,
+    default, observe,
+)
 
 if os.name == 'nt':
     programdata = os.environ.get('PROGRAMDATA', None)
     if programdata:
         SYSTEM_CONFIG_DIRS = [os.path.join(programdata, 'ipython')]
     else:  # PROGRAMDATA is not defined by default on XP.
         SYSTEM_CONFIG_DIRS = []
 else:
     SYSTEM_CONFIG_DIRS = [
         "/usr/local/etc/ipython",
         "/etc/ipython",
     ]
 
 
 # aliases and flags
 
 base_aliases = {
     'profile-dir' : 'ProfileDir.location',
     'profile' : 'BaseIPythonApplication.profile',
     'ipython-dir' : 'BaseIPythonApplication.ipython_dir',
     'log-level' : 'Application.log_level',
     'config' : 'BaseIPythonApplication.extra_config_file',
 }
 
 base_flags = dict(
     debug = ({'Application' : {'log_level' : logging.DEBUG}},
             "set log level to logging.DEBUG (maximize logging output)"),
     quiet = ({'Application' : {'log_level' : logging.CRITICAL}},
             "set log level to logging.CRITICAL (minimize logging output)"),
     init = ({'BaseIPythonApplication' : {
                     'copy_config_files' : True,
                     'auto_create' : True}
             }, """Initialize profile with default config files.  This is equivalent
             to running `ipython profile create <profile>` prior to startup.
             """)
 )
 
 class ProfileAwareConfigLoader(PyFileConfigLoader):
     """A Python file config loader that is aware of IPython profiles."""
     def load_subconfig(self, fname, path=None, profile=None):
         if profile is not None:
             try:
                 profile_dir = ProfileDir.find_profile_dir_by_name(
                         get_ipython_dir(),
                         profile,
                 )
             except ProfileDirError:
                 return
             path = profile_dir.location
         return super(ProfileAwareConfigLoader, self).load_subconfig(fname, path=path)
 
 class BaseIPythonApplication(Application):
 
     name = Unicode(u'ipython')
     description = Unicode(u'IPython: an enhanced interactive Python shell.')
     version = Unicode(release.version)
 
     aliases = Dict(base_aliases)
     flags = Dict(base_flags)
     classes = List([ProfileDir])
     
     # enable `load_subconfig('cfg.py', profile='name')`
     python_config_loader_class = ProfileAwareConfigLoader
 
     # Track whether the config_file has changed,
     # because some logic happens only if we aren't using the default.
     config_file_specified = Set()
 
     config_file_name = Unicode()
+    @default('config_file_name')
     def _config_file_name_default(self):
         return self.name.replace('-','_') + u'_config.py'
-    def _config_file_name_changed(self, name, old, new):
-        if new != old:
-            self.config_file_specified.add(new)
+    @observe('config_file_name')
+    def _config_file_name_changed(self, change):
+        if change['new'] != change['old']:
+            self.config_file_specified.add(change['new'])
 
     # The directory that contains IPython's builtin profiles.
     builtin_profile_dir = Unicode(
         os.path.join(get_ipython_package_dir(), u'config', u'profile', u'default')
     )
     
     config_file_paths = List(Unicode())
+    @default('config_file_paths')
     def _config_file_paths_default(self):
         return [py3compat.getcwd()]
 
-    extra_config_file = Unicode(config=True,
+    extra_config_file = Unicode(
     help="""Path to an extra config file to load.
     
     If specified, load this config file in addition to any other IPython config.
-    """)
-    def _extra_config_file_changed(self, name, old, new):
+    """).tag(config=True)
+    @observe('extra_config_file')
+    def _extra_config_file_changed(self, change):
+        old = change['old']
+        new = change['new']
         try:
             self.config_files.remove(old)
         except ValueError:
             pass
         self.config_file_specified.add(new)
         self.config_files.append(new)
 
-    profile = Unicode(u'default', config=True,
+    profile = Unicode(u'default',
         help="""The IPython profile to use."""
-    )
-
-    def _profile_changed(self, name, old, new):
+    ).tag(config=True)
+    
+    @observe('profile')
+    def _profile_changed(self, change):
         self.builtin_profile_dir = os.path.join(
-                get_ipython_package_dir(), u'config', u'profile', new
+                get_ipython_package_dir(), u'config', u'profile', change['new']
         )
 
-    ipython_dir = Unicode(config=True,
+    ipython_dir = Unicode(
         help="""
         The name of the IPython directory. This directory is used for logging
         configuration (through profiles), history storage, etc. The default
         is usually $HOME/.ipython. This option can also be specified through
         the environment variable IPYTHONDIR.
         """
-    )
+    ).tag(config=True)
+    @default('ipython_dir')
     def _ipython_dir_default(self):
         d = get_ipython_dir()
-        self._ipython_dir_changed('ipython_dir', d, d)
+        self._ipython_dir_changed({
+            'name': 'ipython_dir',
+            'old': d,
+            'new': d,
+        })
         return d
     
     _in_init_profile_dir = False
     profile_dir = Instance(ProfileDir, allow_none=True)
+    @default('profile_dir')
     def _profile_dir_default(self):
         # avoid recursion
         if self._in_init_profile_dir:
             return
         # profile_dir requested early, force initialization
         self.init_profile_dir()
         return self.profile_dir
 
-    overwrite = Bool(False, config=True,
-        help="""Whether to overwrite existing config files when copying""")
-    auto_create = Bool(False, config=True,
-        help="""Whether to create profile dir if it doesn't exist""")
+    overwrite = Bool(False,
+        help="""Whether to overwrite existing config files when copying"""
+    ).tag(config=True)
+    auto_create = Bool(False,
+        help="""Whether to create profile dir if it doesn't exist"""
+    ).tag(config=True)
 
     config_files = List(Unicode())
+    @default('config_files')
     def _config_files_default(self):
         return [self.config_file_name]
 
-    copy_config_files = Bool(False, config=True,
+    copy_config_files = Bool(False,
         help="""Whether to install the default config files into the profile dir.
         If a new profile is being created, and IPython contains config files for that
         profile, then they will be staged into the new directory.  Otherwise,
         default config files will be automatically generated.
-        """)
+        """).tag(config=True)
     
-    verbose_crash = Bool(False, config=True,
+    verbose_crash = Bool(False,
         help="""Create a massive crash report when IPython encounters what may be an
         internal error.  The default is to append a short message to the
-        usual traceback""")
+        usual traceback""").tag(config=True)
 
     # The class to use as the crash handler.
     crash_handler_class = Type(crashhandler.CrashHandler)
 
     @catch_config_error
     def __init__(self, **kwargs):
         super(BaseIPythonApplication, self).__init__(**kwargs)
         # ensure current working directory exists
         try:
             py3compat.getcwd()
         except:
             # exit if cwd doesn't exist
             self.log.error("Current working directory doesn't exist.")
             self.exit(1)
 
     #-------------------------------------------------------------------------
     # Various stages of Application creation
     #-------------------------------------------------------------------------
     
     deprecated_subcommands = {}
     
     def initialize_subcommand(self, subc, argv=None):
         if subc in self.deprecated_subcommands:
-            import time
             self.log.warning("Subcommand `ipython {sub}` is deprecated and will be removed "
                              "in future versions.".format(sub=subc))
             self.log.warning("You likely want to use `jupyter {sub}` in the "
                              "future".format(sub=subc))
         return super(BaseIPythonApplication, self).initialize_subcommand(subc, argv)
 
     def init_crash_handler(self):
         """Create a crash handler, typically setting sys.excepthook to it."""
         self.crash_handler = self.crash_handler_class(self)
         sys.excepthook = self.excepthook
         def unset_crashhandler():
             sys.excepthook = sys.__excepthook__
         atexit.register(unset_crashhandler)
     
     def excepthook(self, etype, evalue, tb):
         """this is sys.excepthook after init_crashhandler
         
         set self.verbose_crash=True to use our full crashhandler, instead of
         a regular traceback with a short message (crash_handler_lite)
         """
         
         if self.verbose_crash:
             return self.crash_handler(etype, evalue, tb)
         else:
             return crashhandler.crash_handler_lite(etype, evalue, tb)
-    
-    def _ipython_dir_changed(self, name, old, new):
+
+    @observe('ipython_dir')
+    def _ipython_dir_changed(self, change):
+        old = change['old']
+        new = change['new']
         if old is not Undefined:
             str_old = py3compat.cast_bytes_py2(os.path.abspath(old),
                 sys.getfilesystemencoding()
             )
             if str_old in sys.path:
                 sys.path.remove(str_old)
         str_path = py3compat.cast_bytes_py2(os.path.abspath(new),
             sys.getfilesystemencoding()
         )
         sys.path.append(str_path)
         ensure_dir_exists(new)
         readme = os.path.join(new, 'README')
         readme_src = os.path.join(get_ipython_package_dir(), u'config', u'profile', 'README')
         if not os.path.exists(readme) and os.path.exists(readme_src):
             shutil.copy(readme_src, readme)
         for d in ('extensions', 'nbextensions'):
             path = os.path.join(new, d)
             try:
                 ensure_dir_exists(path)
             except OSError as e:
                 # this will not be EEXIST
                 self.log.error("couldn't create path %s: %s", path, e)
         self.log.debug("IPYTHONDIR set to: %s" % new)
 
     def load_config_file(self, suppress_errors=True):
         """Load the config file.
 
         By default, errors in loading config are handled, and a warning
         printed on screen. For testing, the suppress_errors option is set
         to False, so errors will make tests fail.
         """
         self.log.debug("Searching path %s for config files", self.config_file_paths)
         base_config = 'ipython_config.py'
         self.log.debug("Attempting to load config file: %s" %
                        base_config)
         try:
             Application.load_config_file(
                 self,
                 base_config,
                 path=self.config_file_paths
             )
         except ConfigFileNotFound:
             # ignore errors loading parent
             self.log.debug("Config file %s not found", base_config)
             pass
         
         for config_file_name in self.config_files:
             if not config_file_name or config_file_name == base_config:
                 continue
             self.log.debug("Attempting to load config file: %s" %
                            self.config_file_name)
             try:
                 Application.load_config_file(
                     self,
                     config_file_name,
                     path=self.config_file_paths
                 )
             except ConfigFileNotFound:
                 # Only warn if the default config file was NOT being used.
                 if config_file_name in self.config_file_specified:
                     msg = self.log.warning
                 else:
                     msg = self.log.debug
                 msg("Config file not found, skipping: %s", config_file_name)
             except Exception:
                 # For testing purposes.
                 if not suppress_errors:
                     raise
                 self.log.warning("Error loading config file: %s" %
                               self.config_file_name, exc_info=True)
 
     def init_profile_dir(self):
         """initialize the profile dir"""
         self._in_init_profile_dir = True
         if self.profile_dir is not None:
             # already ran
             return
         if 'ProfileDir.location' not in self.config:
             # location not specified, find by profile name
             try:
                 p = ProfileDir.find_profile_dir_by_name(self.ipython_dir, self.profile, self.config)
             except ProfileDirError:
                 # not found, maybe create it (always create default profile)
                 if self.auto_create or self.profile == 'default':
                     try:
                         p = ProfileDir.create_profile_dir_by_name(self.ipython_dir, self.profile, self.config)
                     except ProfileDirError:
                         self.log.fatal("Could not create profile: %r"%self.profile)
                         self.exit(1)
                     else:
                         self.log.info("Created profile dir: %r"%p.location)
                 else:
                     self.log.fatal("Profile %r not found."%self.profile)
                     self.exit(1)
             else:
                 self.log.debug("Using existing profile dir: %r"%p.location)
         else:
             location = self.config.ProfileDir.location
             # location is fully specified
             try:
                 p = ProfileDir.find_profile_dir(location, self.config)
             except ProfileDirError:
                 # not found, maybe create it
                 if self.auto_create:
                     try:
                         p = ProfileDir.create_profile_dir(location, self.config)
                     except ProfileDirError:
                         self.log.fatal("Could not create profile directory: %r"%location)
                         self.exit(1)
                     else:
                         self.log.debug("Creating new profile dir: %r"%location)
                 else:
                     self.log.fatal("Profile directory %r not found."%location)
                     self.exit(1)
             else:
                 self.log.info("Using existing profile dir: %r"%location)
             # if profile_dir is specified explicitly, set profile name
             dir_name = os.path.basename(p.location)
             if dir_name.startswith('profile_'):
                 self.profile = dir_name[8:]
 
         self.profile_dir = p
         self.config_file_paths.append(p.location)
         self._in_init_profile_dir = False
 
     def init_config_files(self):
         """[optionally] copy default config files into profile dir."""
         self.config_file_paths.extend(SYSTEM_CONFIG_DIRS)
         # copy config files
         path = self.builtin_profile_dir
         if self.copy_config_files:
             src = self.profile
 
             cfg = self.config_file_name
             if path and os.path.exists(os.path.join(path, cfg)):
                 self.log.warning("Staging %r from %s into %r [overwrite=%s]"%(
                         cfg, src, self.profile_dir.location, self.overwrite)
                 )
                 self.profile_dir.copy_config_file(cfg, path=path, overwrite=self.overwrite)
             else:
                 self.stage_default_config_file()
         else:
             # Still stage *bundled* config files, but not generated ones
             # This is necessary for `ipython profile=sympy` to load the profile
             # on the first go
             files = glob.glob(os.path.join(path, '*.py'))
             for fullpath in files:
                 cfg = os.path.basename(fullpath)
                 if self.profile_dir.copy_config_file(cfg, path=path, overwrite=False):
                     # file was copied
                     self.log.warning("Staging bundled %s from %s into %r"%(
                             cfg, self.profile, self.profile_dir.location)
                     )
 
 
     def stage_default_config_file(self):
         """auto generate default config file, and stage it into the profile."""
         s = self.generate_config_file()
         fname = os.path.join(self.profile_dir.location, self.config_file_name)
         if self.overwrite or not os.path.exists(fname):
             self.log.warning("Generating default config file: %r"%(fname))
             with open(fname, 'w') as f:
                 f.write(s)
 
     @catch_config_error
     def initialize(self, argv=None):
         # don't hook up crash handler before parsing command-line
         self.parse_command_line(argv)
         self.init_crash_handler()
         if self.subapp is not None:
             # stop here if subapp is taking over
             return
         cl_config = self.config
         self.init_profile_dir()
         self.init_config_files()
         self.load_config_file()
         # enforce cl-opts override configfile opts:
         self.update_config(cl_config)

IPython/core/completer.py

@@ -1,1325 +1,1325 b''
 # encoding: utf-8
 """Word completion for IPython.
 
 This module is a fork of the rlcompleter module in the Python standard
 library.  The original enhancements made to rlcompleter have been sent
 upstream and were accepted as of Python 2.3, but we need a lot more
 functionality specific to IPython, so this module will continue to live as an
 IPython-specific utility.
 
 Original rlcompleter documentation:
 
 This requires the latest extension to the readline module (the
 completes keywords, built-ins and globals in __main__; when completing
 NAME.NAME..., it evaluates (!) the expression up to the last dot and
 completes its attributes.
 
 It's very cool to do "import string" type "string.", hit the
 completion key (twice), and see the list of names defined by the
 string module!
 
 Tip: to use the tab key as the completion key, call
 
     readline.parse_and_bind("tab: complete")
 
 Notes:
 
 - Exceptions raised by the completer function are *ignored* (and
   generally cause the completion to fail).  This is a feature -- since
   readline sets the tty device in raw (or cbreak) mode, printing a
   traceback wouldn't work well without some complicated hoopla to save,
   reset and restore the tty state.
 
 - The evaluation of the NAME.NAME... form may cause arbitrary
   application defined code to be executed if an object with a
   ``__getattr__`` hook is found.  Since it is the responsibility of the
   application (or the user) to enable this feature, I consider this an
   acceptable risk.  More complicated expressions (e.g. function calls or
   indexing operations) are *not* evaluated.
 
 - GNU readline is also used by the built-in functions input() and
   raw_input(), and thus these also benefit/suffer from the completer
   features.  Clearly an interactive application can benefit by
   specifying its own completer function and using raw_input() for all
   its input.
 
 - When the original stdin is not a tty device, GNU readline is never
   used, and this module (and the readline module) are silently inactive.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 #
 # Some of this code originated from rlcompleter in the Python standard library
 # Copyright (C) 2001 Python Software Foundation, www.python.org
 
 from __future__ import print_function
 
 import __main__
 import glob
 import inspect
 import itertools
 import keyword
 import os
 import re
 import sys
 import unicodedata
 import string
 
-from traitlets.config.configurable import Configurable 
+from traitlets.config.configurable import Configurable
 from IPython.core.error import TryNext
 from IPython.core.inputsplitter import ESC_MAGIC
 from IPython.core.latex_symbols import latex_symbols, reverse_latex_symbol
 from IPython.utils import generics
 from IPython.utils.decorators import undoc
 from IPython.utils.dir2 import dir2, get_real_method
 from IPython.utils.process import arg_split
 from IPython.utils.py3compat import builtin_mod, string_types, PY3, cast_unicode_py2
-from traitlets import CBool, Enum
+from traitlets import Bool, Enum, observe
 
 import jedi
 import jedi.api.helpers
 import jedi.parser.user_context
 
 #-----------------------------------------------------------------------------
 # Globals
 #-----------------------------------------------------------------------------
 
 # Public API
 __all__ = ['Completer','IPCompleter']
 
 if sys.platform == 'win32':
     PROTECTABLES = ' '
 else:
     PROTECTABLES = ' ()[]{}?=\\|;:\'#*"^&'
 
 
 #-----------------------------------------------------------------------------
 # Main functions and classes
 #-----------------------------------------------------------------------------
 
 def has_open_quotes(s):
     """Return whether a string has open quotes.
 
     This simply counts whether the number of quote characters of either type in
     the string is odd.
 
     Returns
     -------
     If there is an open quote, the quote character is returned.  Else, return
     False.
     """
     # We check " first, then ', so complex cases with nested quotes will get
     # the " to take precedence.
     if s.count('"') % 2:
         return '"'
     elif s.count("'") % 2:
         return "'"
     else:
         return False
 
 
 def protect_filename(s):
     """Escape a string to protect certain characters."""
 
     return "".join([(ch in PROTECTABLES and '\\' + ch or ch)
                     for ch in s])
 
 def expand_user(path):
     """Expand '~'-style usernames in strings.
 
     This is similar to :func:`os.path.expanduser`, but it computes and returns
     extra information that will be useful if the input was being used in
     computing completions, and you wish to return the completions with the
     original '~' instead of its expanded value.
 
     Parameters
     ----------
     path : str
       String to be expanded.  If no ~ is present, the output is the same as the
       input.
 
     Returns
     -------
     newpath : str
       Result of ~ expansion in the input path.
     tilde_expand : bool
       Whether any expansion was performed or not.
     tilde_val : str
       The value that ~ was replaced with.
     """
     # Default values
     tilde_expand = False
     tilde_val = ''
     newpath = path
 
     if path.startswith('~'):
         tilde_expand = True
         rest = len(path)-1
         newpath = os.path.expanduser(path)
         if rest:
             tilde_val = newpath[:-rest]
         else:
             tilde_val = newpath
 
     return newpath, tilde_expand, tilde_val
 
 
 def compress_user(path, tilde_expand, tilde_val):
     """Does the opposite of expand_user, with its outputs.
     """
     if tilde_expand:
         return path.replace(tilde_val, '~')
     else:
         return path
 
 
-
 def completions_sorting_key(word):
     """key for sorting completions
 
     This does several things:
 
     - Lowercase all completions, so they are sorted alphabetically with
       upper and lower case words mingled
     - Demote any completions starting with underscores to the end
     - Insert any %magic and %%cellmagic completions in the alphabetical order
       by their name
     """
     # Case insensitive sort
     word = word.lower()
 
     prio1, prio2 = 0, 0
 
     if word.startswith('__'):
         prio1 = 2
     elif word.startswith('_'):
         prio1 = 1
 
     if word.endswith('='):
         prio1 = -1
 
     if word.startswith('%%'):
         # If there's another % in there, this is something else, so leave it alone
         if not "%" in word[2:]:
             word = word[2:]
             prio2 = 2
     elif word.startswith('%'):
         if not "%" in word[1:]:
             word = word[1:]
             prio2 = 1
 
     return prio1, word, prio2
 
 
 @undoc
 class Bunch(object): pass
 
 
 DELIMS = ' \t\n`!@#$^&*()=+[{]}\\|;:\'",<>?'
 GREEDY_DELIMS = ' =\r\n'
 
 
 class CompletionSplitter(object):
     """An object to split an input line in a manner similar to readline.
 
     By having our own implementation, we can expose readline-like completion in
     a uniform manner to all frontends.  This object only needs to be given the
     line of text to be split and the cursor position on said line, and it
     returns the 'word' to be completed on at the cursor after splitting the
     entire line.
 
     What characters are used as splitting delimiters can be controlled by
     setting the `delims` attribute (this is a property that internally
     automatically builds the necessary regular expression)"""
 
     # Private interface
 
     # A string of delimiter characters.  The default value makes sense for
     # IPython's most typical usage patterns.
     _delims = DELIMS
 
     # The expression (a normal string) to be compiled into a regular expression
     # for actual splitting.  We store it as an attribute mostly for ease of
     # debugging, since this type of code can be so tricky to debug.
     _delim_expr = None
 
     # The regular expression that does the actual splitting
     _delim_re = None
 
     def __init__(self, delims=None):
         delims = CompletionSplitter._delims if delims is None else delims
         self.delims = delims
 
     @property
     def delims(self):
         """Return the string of delimiter characters."""
         return self._delims
 
     @delims.setter
     def delims(self, delims):
         """Set the delimiters for line splitting."""
         expr = '[' + ''.join('\\'+ c for c in delims) + ']'
         self._delim_re = re.compile(expr)
         self._delims = delims
         self._delim_expr = expr
 
     def split_line(self, line, cursor_pos=None):
         """Split a line of text with a cursor at the given position.
         """
         l = line if cursor_pos is None else line[:cursor_pos]
         return self._delim_re.split(l)[-1]
 
 
 class Completer(Configurable):
 
-    greedy = CBool(False, config=True,
+    greedy = Bool(False,
         help="""Activate greedy completion
         PENDING DEPRECTION. this is now mostly taken care of with Jedi.
 
         This will enable completion on elements of lists, results of function calls, etc.,
         but can be unsafe because the code is actually evaluated on TAB.
         """
-    )
+    ).tag(config=True)
     
 
     def __init__(self, namespace=None, global_namespace=None, **kwargs):
         """Create a new completer for the command line.
 
         Completer(namespace=ns, global_namespace=ns2) -> completer instance.
 
         If unspecified, the default namespace where completions are performed
         is __main__ (technically, __main__.__dict__). Namespaces should be
         given as dictionaries.
 
         An optional second namespace can be given.  This allows the completer
         to handle cases where both the local and global scopes need to be
         distinguished.
 
         Completer instances should be used as the completion mechanism of
         readline via the set_completer() call:
 
         readline.set_completer(Completer(my_namespace).complete)
         """
 
         # Don't bind to namespace quite yet, but flag whether the user wants a
         # specific namespace or to use __main__.__dict__. This will allow us
         # to bind to __main__.__dict__ at completion time, not now.
         if namespace is None:
             self.use_main_ns = 1
         else:
             self.use_main_ns = 0
             self.namespace = namespace
 
         # The global namespace, if given, can be bound directly
         if global_namespace is None:
             self.global_namespace = {}
         else:
             self.global_namespace = global_namespace
 
         super(Completer, self).__init__(**kwargs)
 
     def complete(self, text, state):
         """Return the next possible completion for 'text'.
 
         This is called successively with state == 0, 1, 2, ... until it
         returns None.  The completion should begin with 'text'.
 
         """
         if self.use_main_ns:
             self.namespace = __main__.__dict__
 
         if state == 0:
             if "." in text:
                 self.matches = self.attr_matches(text)
             else:
                 self.matches = self.global_matches(text)
         try:
             return self.matches[state]
         except IndexError:
             return None
 
     def global_matches(self, text):
         """Compute matches when text is a simple name.
 
         Return a list of all keywords, built-in functions and names currently
         defined in self.namespace or self.global_namespace that match.
 
         """
         matches = []
         match_append = matches.append
         n = len(text)
         for lst in [keyword.kwlist,
                     builtin_mod.__dict__.keys(),
                     self.namespace.keys(),
                     self.global_namespace.keys()]:
             for word in lst:
                 if word[:n] == text and word != "__builtins__":
                     match_append(word)
         return [cast_unicode_py2(m) for m in matches]
 
     def attr_matches(self, text):
         """Compute matches when text contains a dot.
 
         Assuming the text is of the form NAME.NAME....[NAME], and is
         evaluatable in self.namespace or self.global_namespace, it will be
         evaluated and its attributes (as revealed by dir()) are used as
         possible completions.  (For class instances, class members are are
         also considered.)
 
         WARNING: this can still invoke arbitrary C code, if an object
         with a __getattr__ hook is evaluated.
 
         """
 
         # Another option, seems to work great. Catches things like ''.<tab>
         m = re.match(r"(\S+(\.\w+)*)\.(\w*)$", text)
     
         if m:
             expr, attr = m.group(1, 3)
         elif self.greedy:
             m2 = re.match(r"(.+)\.(\w*)$", self.line_buffer)
             if not m2:
                 return []
             expr, attr = m2.group(1,2)
         else:
             return []
     
         try:
             obj = eval(expr, self.namespace)
         except:
             try:
                 obj = eval(expr, self.global_namespace)
             except:
                 return []
 
         if self.limit_to__all__ and hasattr(obj, '__all__'):
             words = get__all__entries(obj)
         else: 
             words = dir2(obj)
 
         try:
             words = generics.complete_object(obj, words)
         except TryNext:
             pass
         except Exception:
             # Silence errors from completion function
             #raise # dbg
             pass
         # Build match list to return
         n = len(attr)
         return [u"%s.%s" % (expr, w) for w in words if w[:n] == attr ]
 
 
 def get__all__entries(obj):
     """returns the strings in the __all__ attribute"""
     try:
         words = getattr(obj, '__all__')
     except:
         return []
     
     return [cast_unicode_py2(w) for w in words if isinstance(w, string_types)]
 
 
 def match_dict_keys(keys, prefix, delims):
     """Used by dict_key_matches, matching the prefix to a list of keys"""
     if not prefix:
         return None, 0, [repr(k) for k in keys
                       if isinstance(k, (string_types, bytes))]
     quote_match = re.search('["\']', prefix)
     quote = quote_match.group()
     try:
         prefix_str = eval(prefix + quote, {})
     except Exception:
         return None, 0, []
 
     pattern = '[^' + ''.join('\\' + c for c in delims) + ']*$'
     token_match = re.search(pattern, prefix, re.UNICODE)
     token_start = token_match.start()
     token_prefix = token_match.group()
 
     # TODO: support bytes in Py3k
     matched = []
     for key in keys:
         try:
             if not key.startswith(prefix_str):
                 continue
         except (AttributeError, TypeError, UnicodeError):
             # Python 3+ TypeError on b'a'.startswith('a') or vice-versa
             continue
 
         # reformat remainder of key to begin with prefix
         rem = key[len(prefix_str):]
         # force repr wrapped in '
         rem_repr = repr(rem + '"')
         if rem_repr.startswith('u') and prefix[0] not in 'uU':
             # Found key is unicode, but prefix is Py2 string.
             # Therefore attempt to interpret key as string.
             try:
                 rem_repr = repr(rem.encode('ascii') + '"')
             except UnicodeEncodeError:
                 continue
 
         rem_repr = rem_repr[1 + rem_repr.index("'"):-2]
         if quote == '"':
             # The entered prefix is quoted with ",
             # but the match is quoted with '.
             # A contained " hence needs escaping for comparison:
             rem_repr = rem_repr.replace('"', '\\"')
 
         # then reinsert prefix from start of token
         matched.append('%s%s' % (token_prefix, rem_repr))
     return quote, token_start, matched
 
 
 def _safe_isinstance(obj, module, class_name):
     """Checks if obj is an instance of module.class_name if loaded
     """
     return (module in sys.modules and
             isinstance(obj, getattr(__import__(module), class_name)))
 
 
 def back_unicode_name_matches(text):
     u"""Match unicode characters back to unicode name
     
     This does  ☃ -> \\snowman
 
     Note that snowman is not a valid python3 combining character but will be expanded.
     Though it will not recombine back to the snowman character by the completion machinery.
 
     This will not either back-complete standard sequences like \\n, \\b ...
     
     Used on Python 3 only.
     """
     if len(text)<2:
         return u'', ()
     maybe_slash = text[-2]
     if maybe_slash != '\\':
         return u'', ()
 
     char = text[-1]
     # no expand on quote for completion in strings.
     # nor backcomplete standard ascii keys
     if char in string.ascii_letters or char in ['"',"'"]:
         return u'', ()
     try :
         unic = unicodedata.name(char)
         return '\\'+char,['\\'+unic]
-    except KeyError as e:
+    except KeyError:
         pass
     return u'', ()
 
 def back_latex_name_matches(text):
     u"""Match latex characters back to unicode name
     
     This does  ->\\sqrt
 
     Used on Python 3 only.
     """
     if len(text)<2:
         return u'', ()
     maybe_slash = text[-2]
     if maybe_slash != '\\':
         return u'', ()
 
 
     char = text[-1]
     # no expand on quote for completion in strings.
     # nor backcomplete standard ascii keys
     if char in string.ascii_letters or char in ['"',"'"]:
         return u'', ()
     try :
         latex = reverse_latex_symbol[char]
         # '\\' replace the \ as well
         return '\\'+char,[latex]
-    except KeyError as e:
+    except KeyError:
         pass
     return u'', ()
 
 
 class IPCompleter(Completer):
     """Extension of the completer class with IPython-specific features"""
-
-    def _greedy_changed(self, name, old, new):
+    
+    @observe('greedy')
+    def _greedy_changed(self, change):
         """update the splitter and readline delims when greedy is changed"""
-        if new:
+        if change['new']:
             self.splitter.delims = GREEDY_DELIMS
         else:
             self.splitter.delims = DELIMS
 
         if self.readline:
             self.readline.set_completer_delims(self.splitter.delims)
     
-    merge_completions = CBool(True, config=True,
+    merge_completions = Bool(True,
         help="""Whether to merge completion results into a single list
         
         If False, only the completion results from the first non-empty
         completer will be returned.
         """
-    )
-    omit__names = Enum((0,1,2), default_value=2, config=True,
+    ).tag(config=True)
+    omit__names = Enum((0,1,2), default_value=2,
         help="""Instruct the completer to omit private method names
         
         Specifically, when completing on ``object.<tab>``.
         
         When 2 [default]: all names that start with '_' will be excluded.
         
         When 1: all 'magic' names (``__foo__``) will be excluded.
         
         When 0: nothing will be excluded.
         """
-    )
-    limit_to__all__ = CBool(default_value=False, config=True,
+    ).tag(config=True)
+    limit_to__all__ = Bool(False,
         help="""
         DEPRECATED as of version 5.0.
         
         Instruct the completer to use __all__ for the completion
         
         Specifically, when completing on ``object.<tab>``.
         
         When True: only those names in obj.__all__ will be included.
         
         When False [default]: the __all__ attribute is ignored 
-        """
-    )
+        """,
+    ).tag(config=True)
 
     def __init__(self, shell=None, namespace=None, global_namespace=None,
                  use_readline=True, config=None, **kwargs):
         """IPCompleter() -> completer
 
         Return a completer object suitable for use by the readline library
         via readline.set_completer().
 
         Inputs:
 
         - shell: a pointer to the ipython shell itself.  This is needed
           because this completer knows about magic functions, and those can
           only be accessed via the ipython instance.
 
         - namespace: an optional dict where completions are performed.
 
         - global_namespace: secondary optional dict for completions, to
           handle cases (such as IPython embedded inside functions) where
           both Python scopes are visible.
 
         use_readline : bool, optional
           If true, use the readline library.  This completer can still function
           without readline, though in that case callers must provide some extra
           information on each call about the current line."""
 
         self.magic_escape = ESC_MAGIC
         self.splitter = CompletionSplitter()
 
         # Readline configuration, only used by the rlcompleter method.
         if use_readline:
             # We store the right version of readline so that later code
             import IPython.utils.rlineimpl as readline
             self.readline = readline
         else:
             self.readline = None
 
         # _greedy_changed() depends on splitter and readline being defined:
         Completer.__init__(self, namespace=namespace, global_namespace=global_namespace,
                             config=config, **kwargs)
 
         # List where completion matches will be stored
         self.matches = []
         self.shell = shell
         # Regexp to split filenames with spaces in them
         self.space_name_re = re.compile(r'([^\\] )')
         # Hold a local ref. to glob.glob for speed
         self.glob = glob.glob
 
         # Determine if we are running on 'dumb' terminals, like (X)Emacs
         # buffers, to avoid completion problems.
         term = os.environ.get('TERM','xterm')
         self.dumb_terminal = term in ['dumb','emacs']
 
         # Special handling of backslashes needed in win32 platforms
         if sys.platform == "win32":
             self.clean_glob = self._clean_glob_win32
         else:
             self.clean_glob = self._clean_glob
 
         #regexp to parse docstring for function signature
         self.docstring_sig_re = re.compile(r'^[\w|\s.]+\(([^)]*)\).*')
         self.docstring_kwd_re = re.compile(r'[\s|\[]*(\w+)(?:\s*=\s*.*)')
         #use this if positional argument name is also needed
         #= re.compile(r'[\s|\[]*(\w+)(?:\s*=?\s*.*)')
 
         # All active matcher routines for completion
         self.matchers = [
                          self.file_matches,
                          self.magic_matches,
                          self.python_func_kw_matches,
                          self.dict_key_matches,
                          ]
 
     def all_completions(self, text):
         """
         Wrapper around the complete method for the benefit of emacs
         and pydb.
         """
         return self.complete(text)[1]
 
     def _clean_glob(self, text):
         return self.glob("%s*" % text)
 
     def _clean_glob_win32(self,text):
         return [f.replace("\\","/")
                 for f in self.glob("%s*" % text)]
 
     def file_matches(self, text):
         """Match filenames, expanding ~USER type strings.
 
         Most of the seemingly convoluted logic in this completer is an
         attempt to handle filenames with spaces in them.  And yet it's not
         quite perfect, because Python's readline doesn't expose all of the
         GNU readline details needed for this to be done correctly.
 
         For a filename with a space in it, the printed completions will be
         only the parts after what's already been typed (instead of the
         full completions, as is normally done).  I don't think with the
         current (as of Python 2.3) Python readline it's possible to do
         better."""
 
         # chars that require escaping with backslash - i.e. chars
         # that readline treats incorrectly as delimiters, but we
         # don't want to treat as delimiters in filename matching
         # when escaped with backslash
         if text.startswith('!'):
             text = text[1:]
             text_prefix = u'!'
         else:
             text_prefix = u''
 
         text_until_cursor = self.text_until_cursor
         # track strings with open quotes
         open_quotes = has_open_quotes(text_until_cursor)
 
         if '(' in text_until_cursor or '[' in text_until_cursor:
             lsplit = text
         else:
             try:
                 # arg_split ~ shlex.split, but with unicode bugs fixed by us
                 lsplit = arg_split(text_until_cursor)[-1]
             except ValueError:
                 # typically an unmatched ", or backslash without escaped char.
                 if open_quotes:
                     lsplit = text_until_cursor.split(open_quotes)[-1]
                 else:
                     return []
             except IndexError:
                 # tab pressed on empty line
                 lsplit = ""
 
         if not open_quotes and lsplit != protect_filename(lsplit):
             # if protectables are found, do matching on the whole escaped name
             has_protectables = True
             text0,text = text,lsplit
         else:
             has_protectables = False
             text = os.path.expanduser(text)
 
         if text == "":
             return [text_prefix + cast_unicode_py2(protect_filename(f)) for f in self.glob("*")]
 
         # Compute the matches from the filesystem
         m0 = self.clean_glob(text.replace('\\',''))
 
         if has_protectables:
             # If we had protectables, we need to revert our changes to the
             # beginning of filename so that we don't double-write the part
             # of the filename we have so far
             len_lsplit = len(lsplit)
             matches = [text_prefix + text0 +
                        protect_filename(f[len_lsplit:]) for f in m0]
         else:
             if open_quotes:
                 # if we have a string with an open quote, we don't need to
                 # protect the names at all (and we _shouldn't_, as it
                 # would cause bugs when the filesystem call is made).
                 matches = m0
             else:
                 matches = [text_prefix +
                            protect_filename(f) for f in m0]
 
         # Mark directories in input list by appending '/' to their names.
         return [cast_unicode_py2(x+'/') if os.path.isdir(x) else x for x in matches]
 
     def magic_matches(self, text):
         """Match magics"""
         # Get all shell magics now rather than statically, so magics loaded at
         # runtime show up too.
         lsm = self.shell.magics_manager.lsmagic()
         line_magics = lsm['line']
         cell_magics = lsm['cell']
         pre = self.magic_escape
         pre2 = pre+pre
         
         # Completion logic:
         # - user gives %%: only do cell magics
         # - user gives %: do both line and cell magics
         # - no prefix: do both
         # In other words, line magics are skipped if the user gives %% explicitly
         bare_text = text.lstrip(pre)
         comp = [ pre2+m for m in cell_magics if m.startswith(bare_text)]
         if not text.startswith(pre2):
             comp += [ pre+m for m in line_magics if m.startswith(bare_text)]
         return [cast_unicode_py2(c) for c in comp]
 
     def python_jedi_matches(self, text, line_buffer, cursor_pos):
         """Match attributes or global Python names using Jedi."""
         if line_buffer.startswith('aimport ') or line_buffer.startswith('%aimport '):
             return ()
         namespaces = []
         if self.namespace is None:
             import __main__
             namespaces.append(__main__.__dict__)
         else:
             namespaces.append(self.namespace)
         if self.global_namespace is not None:
             namespaces.append(self.global_namespace)
 
         # cursor_pos is an it, jedi wants line and column
 
         interpreter = jedi.Interpreter(line_buffer, namespaces, column=cursor_pos)
         path = jedi.parser.user_context.UserContext(line_buffer, \
                 (1, len(line_buffer))).get_path_until_cursor()
         path, dot, like = jedi.api.helpers.completion_parts(path)
         if text.startswith('.'):
             # text will be `.` on completions like `a[0].<tab>`
             before = dot
         else:
             before = line_buffer[:len(line_buffer) - len(like)]
 
 
         def trim_start(completion):
             """completions need to start with `text`, trim the beginning until it does"""
             ltext = text.lower()
             lcomp  = completion.lower()
             if ltext in lcomp and not (lcomp.startswith(ltext)):
                 start_index = lcomp.index(ltext)
                 if cursor_pos:
                     if start_index >= cursor_pos:
                         start_index = min(start_index, cursor_pos)
                 return completion[start_index:]
             return completion
         
         completions = interpreter.completions()
 
         completion_text = [c.name_with_symbols for c in completions]
 
         if self.omit__names:
             if self.omit__names == 1:
                 # true if txt is _not_ a __ name, false otherwise:
                 no__name = lambda txt: not txt.startswith('__')
             else:
                 # true if txt is _not_ a _ name, false otherwise:
                 no__name = lambda txt: not txt.startswith('_')
             completion_text = filter(no__name, completion_text)
 
 
         return [trim_start(before + c_text) for c_text in completion_text]
 
 
     def python_matches(self, text):
         """Match attributes or global python names"""
         if "." in text:
             try:
                 matches = self.attr_matches(text)
                 if text.endswith('.') and self.omit__names:
                     if self.omit__names == 1:
                         # true if txt is _not_ a __ name, false otherwise:
                         no__name = (lambda txt:
                                     re.match(r'.*\.__.*?__',txt) is None)
                     else:
                         # true if txt is _not_ a _ name, false otherwise:
                         no__name = (lambda txt:
                                     re.match(r'\._.*?',txt[txt.rindex('.'):]) is None)
                     matches = filter(no__name, matches)
             except NameError:
                 # catches <undefined attributes>.<tab>
                 matches = []
         else:
             matches = self.global_matches(text)
         return matches
 
     def _default_arguments_from_docstring(self, doc):
         """Parse the first line of docstring for call signature.
 
         Docstring should be of the form 'min(iterable[, key=func])\n'.
         It can also parse cython docstring of the form
         'Minuit.migrad(self, int ncall=10000, resume=True, int nsplit=1)'.
         """
         if doc is None:
             return []
 
         #care only the firstline
         line = doc.lstrip().splitlines()[0]
 
         #p = re.compile(r'^[\w|\s.]+\(([^)]*)\).*')
         #'min(iterable[, key=func])\n' -> 'iterable[, key=func]'
         sig = self.docstring_sig_re.search(line)
         if sig is None:
             return []
         # iterable[, key=func]' -> ['iterable[' ,' key=func]']
         sig = sig.groups()[0].split(',')
         ret = []
         for s in sig:
             #re.compile(r'[\s|\[]*(\w+)(?:\s*=\s*.*)')
             ret += self.docstring_kwd_re.findall(s)
         return ret
 
     def _default_arguments(self, obj):
         """Return the list of default arguments of obj if it is callable,
         or empty list otherwise."""
         call_obj = obj
         ret = []
         if inspect.isbuiltin(obj):
             pass
         elif not (inspect.isfunction(obj) or inspect.ismethod(obj)):
             if inspect.isclass(obj):
                 #for cython embededsignature=True the constructor docstring
                 #belongs to the object itself not __init__
                 ret += self._default_arguments_from_docstring(
                             getattr(obj, '__doc__', ''))
                 # for classes, check for __init__,__new__
                 call_obj = (getattr(obj, '__init__', None) or
                        getattr(obj, '__new__', None))
             # for all others, check if they are __call__able
             elif hasattr(obj, '__call__'):
                 call_obj = obj.__call__
         ret += self._default_arguments_from_docstring(
                  getattr(call_obj, '__doc__', ''))
 
         if PY3:
             _keeps = (inspect.Parameter.KEYWORD_ONLY,
                       inspect.Parameter.POSITIONAL_OR_KEYWORD)
             signature = inspect.signature
         else:
             import IPython.utils.signatures
             _keeps = (IPython.utils.signatures.Parameter.KEYWORD_ONLY,
                       IPython.utils.signatures.Parameter.POSITIONAL_OR_KEYWORD)
             signature = IPython.utils.signatures.signature
 
         try:
             sig = signature(call_obj)
             ret.extend(k for k, v in sig.parameters.items() if
                        v.kind in _keeps)
         except ValueError:
             pass
 
         return list(set(ret))
 
     def python_func_kw_matches(self,text):
         """Match named parameters (kwargs) of the last open function"""
 
         if "." in text: # a parameter cannot be dotted
             return []
         try: regexp = self.__funcParamsRegex
         except AttributeError:
             regexp = self.__funcParamsRegex = re.compile(r'''
                 '.*?(?<!\\)' |    # single quoted strings or
                 ".*?(?<!\\)" |    # double quoted strings or
                 \w+          |    # identifier
                 \S                # other characters
                 ''', re.VERBOSE | re.DOTALL)
         # 1. find the nearest identifier that comes before an unclosed
         # parenthesis before the cursor
         # e.g. for "foo (1+bar(x), pa<cursor>,a=1)", the candidate is "foo"
         tokens = regexp.findall(self.text_until_cursor)
         tokens.reverse()
         iterTokens = iter(tokens); openPar = 0
 
         for token in iterTokens:
             if token == ')':
                 openPar -= 1
             elif token == '(':
                 openPar += 1
                 if openPar > 0:
                     # found the last unclosed parenthesis
                     break
         else:
             return []
         # 2. Concatenate dotted names ("foo.bar" for "foo.bar(x, pa" )
         ids = []
         isId = re.compile(r'\w+$').match
 
         while True:
             try:
                 ids.append(next(iterTokens))
                 if not isId(ids[-1]):
                     ids.pop(); break
                 if not next(iterTokens) == '.':
                     break
             except StopIteration:
                 break
         # lookup the candidate callable matches either using global_matches
         # or attr_matches for dotted names
         if len(ids) == 1:
             callableMatches = self.global_matches(ids[0])
         else:
             callableMatches = self.attr_matches('.'.join(ids[::-1]))
         argMatches = []
         for callableMatch in callableMatches:
             try:
                 namedArgs = self._default_arguments(eval(callableMatch,
                                                         self.namespace))
             except:
                 continue
 
             for namedArg in namedArgs:
                 if namedArg.startswith(text):
                     argMatches.append(u"%s=" %namedArg)
         return argMatches
 
     def dict_key_matches(self, text):
         "Match string keys in a dictionary, after e.g. 'foo[' "
         def get_keys(obj):
             # Objects can define their own completions by defining an
             # _ipy_key_completions_() method.
             method = get_real_method(obj, '_ipython_key_completions_')
             if method is not None:
                 return method()
 
             # Special case some common in-memory dict-like types
             if isinstance(obj, dict) or\
                _safe_isinstance(obj, 'pandas', 'DataFrame'):
                 try:
                     return list(obj.keys())
                 except Exception:
                     return []
             elif _safe_isinstance(obj, 'numpy', 'ndarray') or\
                  _safe_isinstance(obj, 'numpy', 'void'):
                 return obj.dtype.names or []
             return []
 
         try:
             regexps = self.__dict_key_regexps
         except AttributeError:
             dict_key_re_fmt = r'''(?x)
             (  # match dict-referring expression wrt greedy setting
                 %s
             )
             \[   # open bracket
             \s*  # and optional whitespace
             ([uUbB]?  # string prefix (r not handled)
                 (?:   # unclosed string
                     '(?:[^']|(?<!\\)\\')*
                 |
                     "(?:[^"]|(?<!\\)\\")*
                 )
             )?
             $
             '''
             regexps = self.__dict_key_regexps = {
                 False: re.compile(dict_key_re_fmt % '''
                                   # identifiers separated by .
                                   (?!\d)\w+
                                   (?:\.(?!\d)\w+)*
                                   '''),
                 True: re.compile(dict_key_re_fmt % '''
                                  .+
                                  ''')
             }
 
         match = regexps[self.greedy].search(self.text_until_cursor)
         if match is None:
             return []
 
         expr, prefix = match.groups()
         try:
             obj = eval(expr, self.namespace)
         except Exception:
             try:
                 obj = eval(expr, self.global_namespace)
             except Exception:
                 return []
 
         keys = get_keys(obj)
         if not keys:
             return keys
         closing_quote, token_offset, matches = match_dict_keys(keys, prefix, self.splitter.delims)
         if not matches:
             return matches
         
         # get the cursor position of
         # - the text being completed
         # - the start of the key text
         # - the start of the completion
         text_start = len(self.text_until_cursor) - len(text)
         if prefix:
             key_start = match.start(2)
             completion_start = key_start + token_offset
         else:
             key_start = completion_start = match.end()
         
         # grab the leading prefix, to make sure all completions start with `text`
         if text_start > key_start:
             leading = ''
         else:
             leading = text[text_start:completion_start]
         
         # the index of the `[` character
         bracket_idx = match.end(1)
 
         # append closing quote and bracket as appropriate
         # this is *not* appropriate if the opening quote or bracket is outside
         # the text given to this method
         suf = ''
         continuation = self.line_buffer[len(self.text_until_cursor):]
         if key_start > text_start and closing_quote:
             # quotes were opened inside text, maybe close them
             if continuation.startswith(closing_quote):
                 continuation = continuation[len(closing_quote):]
             else:
                 suf += closing_quote
         if bracket_idx > text_start:
             # brackets were opened inside text, maybe close them
             if not continuation.startswith(']'):
                 suf += ']'
         
         return [leading + k + suf for k in matches]
 
     def unicode_name_matches(self, text):
         u"""Match Latex-like syntax for unicode characters base 
         on the name of the character.
         
         This does  \\GREEK SMALL LETTER ETA -> η
 
         Works only on valid python 3 identifier, or on combining characters that 
         will combine to form a valid identifier.
         
         Used on Python 3 only.
         """
         slashpos = text.rfind('\\')
         if slashpos > -1:
             s = text[slashpos+1:]
             try :
                 unic = unicodedata.lookup(s)
                 # allow combining chars
                 if ('a'+unic).isidentifier():
                     return '\\'+s,[unic]
-            except KeyError as e:
+            except KeyError:
                 pass
         return u'', []
 
 
 
 
     def latex_matches(self, text):
         u"""Match Latex syntax for unicode characters.
         
         This does both \\alp -> \\alpha and \\alpha -> α
         
         Used on Python 3 only.
         """
         slashpos = text.rfind('\\')
         if slashpos > -1:
             s = text[slashpos:]
             if s in latex_symbols:
                 # Try to complete a full latex symbol to unicode
                 # \\alpha -> α
                 return s, [latex_symbols[s]]
             else:
                 # If a user has partially typed a latex symbol, give them
                 # a full list of options \al -> [\aleph, \alpha]
                 matches = [k for k in latex_symbols if k.startswith(s)]
                 return s, matches
         return u'', []
 
     def dispatch_custom_completer(self, text):
         line = self.line_buffer
         if not line.strip():
             return None
 
         # Create a little structure to pass all the relevant information about
         # the current completion to any custom completer.
         event = Bunch()
         event.line = line
         event.symbol = text
         cmd = line.split(None,1)[0]
         event.command = cmd
         event.text_until_cursor = self.text_until_cursor
 
         # for foo etc, try also to find completer for %foo
         if not cmd.startswith(self.magic_escape):
             try_magic = self.custom_completers.s_matches(
                 self.magic_escape + cmd)
         else:
             try_magic = []
 
         for c in itertools.chain(self.custom_completers.s_matches(cmd),
                  try_magic,
                  self.custom_completers.flat_matches(self.text_until_cursor)):
             try:
                 res = c(event)
                 if res:
                     # first, try case sensitive match
                     withcase = [cast_unicode_py2(r) for r in res if r.startswith(text)]
                     if withcase:
                         return withcase
                     # if none, then case insensitive ones are ok too
                     text_low = text.lower()
                     return [cast_unicode_py2(r) for r in res if r.lower().startswith(text_low)]
             except TryNext:
                 pass
 
         return None
 
     def complete(self, text=None, line_buffer=None, cursor_pos=None):
         """Find completions for the given text and line context.
 
         Note that both the text and the line_buffer are optional, but at least
         one of them must be given.
 
         Parameters
         ----------
           text : string, optional
             Text to perform the completion on.  If not given, the line buffer
             is split using the instance's CompletionSplitter object.
 
           line_buffer : string, optional
             If not given, the completer attempts to obtain the current line
             buffer via readline.  This keyword allows clients which are
             requesting for text completions in non-readline contexts to inform
             the completer of the entire text.
 
           cursor_pos : int, optional
             Index of the cursor in the full line buffer.  Should be provided by
             remote frontends where kernel has no access to frontend state.
 
         Returns
         -------
         text : str
           Text that was actually used in the completion.
 
         matches : list
           A list of completion matches.
         """
         # if the cursor position isn't given, the only sane assumption we can
         # make is that it's at the end of the line (the common case)
         if cursor_pos is None:
             cursor_pos = len(line_buffer) if text is None else len(text)
 
         if PY3:
 
             base_text = text if not line_buffer else line_buffer[:cursor_pos]
             latex_text, latex_matches = self.latex_matches(base_text)
             if latex_matches:
                  return latex_text, latex_matches
             name_text = ''
             name_matches = []
             for meth in (self.unicode_name_matches, back_latex_name_matches, back_unicode_name_matches):
                 name_text, name_matches = meth(base_text)
                 if name_text:
                     return name_text, name_matches
         
         # if text is either None or an empty string, rely on the line buffer
         if not text:
             text = self.splitter.split_line(line_buffer, cursor_pos)
 
         # If no line buffer is given, assume the input text is all there was
         if line_buffer is None:
             line_buffer = text
 
         self.line_buffer = line_buffer
         self.text_until_cursor = self.line_buffer[:cursor_pos]
 
         # Start with a clean slate of completions
         self.matches[:] = []
         custom_res = self.dispatch_custom_completer(text)
         if custom_res is not None:
             # did custom completers produce something?
             self.matches = custom_res
         else:
             # Extend the list of completions with the results of each
             # matcher, so we return results to the user from all
             # namespaces.
             if self.merge_completions:
                 self.matches = []
                 for matcher in self.matchers:
                     try:
                         self.matches.extend(matcher(text))
                     except:
                         # Show the ugly traceback if the matcher causes an
                         # exception, but do NOT crash the kernel!
                         sys.excepthook(*sys.exc_info())
             else:
                 for matcher in self.matchers:
                     self.matches = matcher(text)
                     if self.matches:
                         break
         # FIXME: we should extend our api to return a dict with completions for
         # different types of objects.  The rlcomplete() method could then
         # simply collapse the dict into a list for readline, but we'd have
         # richer completion semantics in other evironments.
         self.matches.extend(self.python_jedi_matches(text, line_buffer, cursor_pos))
 
         self.matches = sorted(set(self.matches), key=completions_sorting_key)
 
         return text, self.matches
 
     def rlcomplete(self, text, state):
         """Return the state-th possible completion for 'text'.
 
         This is called successively with state == 0, 1, 2, ... until it
         returns None.  The completion should begin with 'text'.
 
         Parameters
         ----------
           text : string
             Text to perform the completion on.
 
           state : int
             Counter used by readline.
         """
         if state==0:
 
             self.line_buffer = line_buffer = self.readline.get_line_buffer()
             cursor_pos = self.readline.get_endidx()
 
             #io.rprint("\nRLCOMPLETE: %r %r %r" %
             #          (text, line_buffer, cursor_pos) ) # dbg
 
             # if there is only a tab on a line with only whitespace, instead of
             # the mostly useless 'do you want to see all million completions'
             # message, just do the right thing and give the user his tab!
             # Incidentally, this enables pasting of tabbed text from an editor
             # (as long as autoindent is off).
 
             # It should be noted that at least pyreadline still shows file
             # completions - is there a way around it?
 
             # don't apply this on 'dumb' terminals, such as emacs buffers, so
             # we don't interfere with their own tab-completion mechanism.
             if not (self.dumb_terminal or line_buffer.strip()):
                 self.readline.insert_text('\t')
                 sys.stdout.flush()
                 return None
 
             # Note: debugging exceptions that may occur in completion is very
             # tricky, because readline unconditionally silences them.  So if
             # during development you suspect a bug in the completion code, turn
             # this flag on temporarily by uncommenting the second form (don't
             # flip the value in the first line, as the '# dbg' marker can be
             # automatically detected and is used elsewhere).
             DEBUG = False
             #DEBUG = True # dbg
             if DEBUG:
                 try:
                     self.complete(text, line_buffer, cursor_pos)
                 except:
                     import traceback; traceback.print_exc()
             else:
                 # The normal production version is here
 
                 # This method computes the self.matches array
                 self.complete(text, line_buffer, cursor_pos)
 
         try:
             return self.matches[state]
         except IndexError:
             return None
 

IPython/core/formatters.py

@@ -1,951 +1,960 b''
 # -*- coding: utf-8 -*-
 """Display formatters.
 
 Inheritance diagram:
 
 .. inheritance-diagram:: IPython.core.formatters
    :parts: 3
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import abc
 import json
 import sys
 import traceback
 import warnings
 
 from decorator import decorator
 
 from traitlets.config.configurable import Configurable
 from IPython.core.getipython import get_ipython
 from IPython.utils.sentinel import Sentinel
 from IPython.utils.dir2 import get_real_method
 from IPython.lib import pretty
 from traitlets import (
     Bool, Dict, Integer, Unicode, CUnicode, ObjectName, List,
     ForwardDeclaredInstance,
+    default, observe,
 )
 from IPython.utils.py3compat import (
     with_metaclass, string_types, unicode_type,
 )
 
 
 class DisplayFormatter(Configurable):
 
     # When set to true only the default plain text formatter will be used.
     plain_text_only = Bool(False).tag(config=True)
     def _plain_text_only_changed(self, name, old, new):
         warnings.warn("""DisplayFormatter.plain_text_only is deprecated.
         
         It will be removed in IPython 5.0
 
         Use DisplayFormatter.active_types = ['text/plain']
         for the same effect.
         """, DeprecationWarning)
         if new:
             self.active_types = ['text/plain']
         else:
             self.active_types = self.format_types
     
-    active_types = List(Unicode()).tag(config=True,
+    active_types = List(Unicode(),
         help="""List of currently active mime-types to display.
         You can use this to set a white-list for formats to display.
         
         Most users will not need to change this value.
-        """)
+        """).tag(config=True)
+
+    @default('active_types')
     def _active_types_default(self):
         return self.format_types
-    
-    def _active_types_changed(self, name, old, new):
+
+    @observe('active_types')
+    def _active_types_changed(self, change):
         for key, formatter in self.formatters.items():
-            if key in new:
+            if key in change['new']:
                 formatter.enabled = True
             else:
                 formatter.enabled = False
     
     ipython_display_formatter = ForwardDeclaredInstance('FormatterABC')
-    def _ipython_display_formatter_default(self):
+    @default('ipython_display_formatter')
+    def _default_formatter(self):
         return IPythonDisplayFormatter(parent=self)
     
     # A dict of formatter whose keys are format types (MIME types) and whose
     # values are subclasses of BaseFormatter.
     formatters = Dict()
+    @default('formatters')
     def _formatters_default(self):
         """Activate the default formatters."""
         formatter_classes = [
             PlainTextFormatter,
             HTMLFormatter,
             MarkdownFormatter,
             SVGFormatter,
             PNGFormatter,
             PDFFormatter,
             JPEGFormatter,
             LatexFormatter,
             JSONFormatter,
             JavascriptFormatter
         ]
         d = {}
         for cls in formatter_classes:
             f = cls(parent=self)
             d[f.format_type] = f
         return d
 
     def format(self, obj, include=None, exclude=None):
         """Return a format data dict for an object.
 
         By default all format types will be computed.
 
         The following MIME types are currently implemented:
 
         * text/plain
         * text/html
         * text/markdown
         * text/latex
         * application/json
         * application/javascript
         * application/pdf
         * image/png
         * image/jpeg
         * image/svg+xml
 
         Parameters
         ----------
         obj : object
             The Python object whose format data will be computed.
         include : list or tuple, optional
             A list of format type strings (MIME types) to include in the
             format data dict. If this is set *only* the format types included
             in this list will be computed.
         exclude : list or tuple, optional
             A list of format type string (MIME types) to exclude in the format
             data dict. If this is set all format types will be computed,
             except for those included in this argument.
 
         Returns
         -------
         (format_dict, metadata_dict) : tuple of two dicts
         
             format_dict is a dictionary of key/value pairs, one of each format that was
             generated for the object. The keys are the format types, which
             will usually be MIME type strings and the values and JSON'able
             data structure containing the raw data for the representation in
             that format.
             
             metadata_dict is a dictionary of metadata about each mime-type output.
             Its keys will be a strict subset of the keys in format_dict.
         """
         format_dict = {}
         md_dict = {}
         
         if self.ipython_display_formatter(obj):
             # object handled itself, don't proceed
             return {}, {}
         
         for format_type, formatter in self.formatters.items():
             if include and format_type not in include:
                 continue
             if exclude and format_type in exclude:
                 continue
             
             md = None
             try:
                 data = formatter(obj)
             except:
                 # FIXME: log the exception
                 raise
             
             # formatters can return raw data or (data, metadata)
             if isinstance(data, tuple) and len(data) == 2:
                 data, md = data
             
             if data is not None:
                 format_dict[format_type] = data
             if md is not None:
                 md_dict[format_type] = md
             
         return format_dict, md_dict
 
     @property
     def format_types(self):
         """Return the format types (MIME types) of the active formatters."""
         return list(self.formatters.keys())
 
 
 #-----------------------------------------------------------------------------
 # Formatters for specific format types (text, html, svg, etc.)
 #-----------------------------------------------------------------------------
 
 
 def _safe_repr(obj):
     """Try to return a repr of an object
 
     always returns a string, at least.
     """
     try:
         return repr(obj)
     except Exception as e:
         return "un-repr-able object (%r)" % e
 
 
 class FormatterWarning(UserWarning):
     """Warning class for errors in formatters"""
 
 @decorator
 def catch_format_error(method, self, *args, **kwargs):
     """show traceback on failed format call"""
     try:
         r = method(self, *args, **kwargs)
     except NotImplementedError:
         # don't warn on NotImplementedErrors
         return None
     except Exception:
         exc_info = sys.exc_info()
         ip = get_ipython()
         if ip is not None:
             ip.showtraceback(exc_info)
         else:
             traceback.print_exception(*exc_info)
         return None
     return self._check_return(r, args[0])
 
 
 class FormatterABC(with_metaclass(abc.ABCMeta, object)):
     """ Abstract base class for Formatters.
 
     A formatter is a callable class that is responsible for computing the
     raw format data for a particular format type (MIME type). For example,
     an HTML formatter would have a format type of `text/html` and would return
     the HTML representation of the object when called.
     """
 
     # The format type of the data returned, usually a MIME type.
     format_type = 'text/plain'
 
     # Is the formatter enabled...
     enabled = True
     
     @abc.abstractmethod
     def __call__(self, obj):
         """Return a JSON'able representation of the object.
 
         If the object cannot be formatted by this formatter,
         warn and return None.
         """
         return repr(obj)
 
 
 def _mod_name_key(typ):
     """Return a (__module__, __name__) tuple for a type.
     
     Used as key in Formatter.deferred_printers.
     """
     module = getattr(typ, '__module__', None)
     name = getattr(typ, '__name__', None)
     return (module, name)
 
 
 def _get_type(obj):
     """Return the type of an instance (old and new-style)"""
     return getattr(obj, '__class__', None) or type(obj)
 
 
 _raise_key_error = Sentinel('_raise_key_error', __name__, 
 """
 Special value to raise a KeyError
 
 Raise KeyError in `BaseFormatter.pop` if passed as the default value to `pop`
 """)
 
 
 class BaseFormatter(Configurable):
     """A base formatter class that is configurable.
 
     This formatter should usually be used as the base class of all formatters.
     It is a traited :class:`Configurable` class and includes an extensible
     API for users to determine how their objects are formatted. The following
     logic is used to find a function to format an given object.
 
     1. The object is introspected to see if it has a method with the name
        :attr:`print_method`. If is does, that object is passed to that method
        for formatting.
     2. If no print method is found, three internal dictionaries are consulted
        to find print method: :attr:`singleton_printers`, :attr:`type_printers`
        and :attr:`deferred_printers`.
 
     Users should use these dictionaries to register functions that will be
     used to compute the format data for their objects (if those objects don't
     have the special print methods). The easiest way of using these
     dictionaries is through the :meth:`for_type` and :meth:`for_type_by_name`
     methods.
 
     If no function/callable is found to compute the format data, ``None`` is
     returned and this format type is not used.
     """
 
     format_type = Unicode('text/plain')
     _return_type = string_types
 
     enabled = Bool(True).tag(config=True)
 
     print_method = ObjectName('__repr__')
 
     # The singleton printers.
     # Maps the IDs of the builtin singleton objects to the format functions.
     singleton_printers = Dict().tag(config=True)
 
     # The type-specific printers.
     # Map type objects to the format functions.
     type_printers = Dict().tag(config=True)
 
     # The deferred-import type-specific printers.
     # Map (modulename, classname) pairs to the format functions.
     deferred_printers = Dict().tag(config=True)
     
     @catch_format_error
     def __call__(self, obj):
         """Compute the format for an object."""
         if self.enabled:
             # lookup registered printer
             try:
                 printer = self.lookup(obj)
             except KeyError:
                 pass
             else:
                 return printer(obj)
             # Finally look for special method names
             method = get_real_method(obj, self.print_method)
             if method is not None:
                 return method()
             return None
         else:
             return None
     
     def __contains__(self, typ):
         """map in to lookup_by_type"""
         try:
             self.lookup_by_type(typ)
         except KeyError:
             return False
         else:
             return True
     
     def _check_return(self, r, obj):
         """Check that a return value is appropriate
         
         Return the value if so, None otherwise, warning if invalid.
         """
         if r is None or isinstance(r, self._return_type) or \
             (isinstance(r, tuple) and r and isinstance(r[0], self._return_type)):
             return r
         else:
             warnings.warn(
                 "%s formatter returned invalid type %s (expected %s) for object: %s" % \
                 (self.format_type, type(r), self._return_type, _safe_repr(obj)),
                 FormatterWarning
             )
     
     def lookup(self, obj):
         """Look up the formatter for a given instance.
         
         Parameters
         ----------
         obj  : object instance
 
         Returns
         -------
         f : callable
             The registered formatting callable for the type.
 
         Raises
         ------
         KeyError if the type has not been registered.
         """
         # look for singleton first
         obj_id = id(obj)
         if obj_id in self.singleton_printers:
             return self.singleton_printers[obj_id]
         # then lookup by type
         return self.lookup_by_type(_get_type(obj))
     
     def lookup_by_type(self, typ):
         """Look up the registered formatter for a type.
 
         Parameters
         ----------
         typ  : type or '__module__.__name__' string for a type
 
         Returns
         -------
         f : callable
             The registered formatting callable for the type.
 
         Raises
         ------
         KeyError if the type has not been registered.
         """
         if isinstance(typ, string_types):
             typ_key = tuple(typ.rsplit('.',1))
             if typ_key not in self.deferred_printers:
                 # We may have it cached in the type map. We will have to
                 # iterate over all of the types to check.
                 for cls in self.type_printers:
                     if _mod_name_key(cls) == typ_key:
                         return self.type_printers[cls]
             else:
                 return self.deferred_printers[typ_key]
         else:
             for cls in pretty._get_mro(typ):
                 if cls in self.type_printers or self._in_deferred_types(cls):
                     return self.type_printers[cls]
         
         # If we have reached here, the lookup failed.
         raise KeyError("No registered printer for {0!r}".format(typ))
 
     def for_type(self, typ, func=None):
         """Add a format function for a given type.
         
         Parameters
         -----------
         typ : type or '__module__.__name__' string for a type
             The class of the object that will be formatted using `func`.
         func : callable
             A callable for computing the format data.
             `func` will be called with the object to be formatted,
             and will return the raw data in this formatter's format.
             Subclasses may use a different call signature for the
             `func` argument.
             
             If `func` is None or not specified, there will be no change,
             only returning the current value.
         
         Returns
         -------
         oldfunc : callable
             The currently registered callable.
             If you are registering a new formatter,
             this will be the previous value (to enable restoring later).
         """
         # if string given, interpret as 'pkg.module.class_name'
         if isinstance(typ, string_types):
             type_module, type_name = typ.rsplit('.', 1)
             return self.for_type_by_name(type_module, type_name, func)
         
         try:
             oldfunc = self.lookup_by_type(typ)
         except KeyError:
             oldfunc = None
         
         if func is not None:
             self.type_printers[typ] = func
         
         return oldfunc
 
     def for_type_by_name(self, type_module, type_name, func=None):
         """Add a format function for a type specified by the full dotted
         module and name of the type, rather than the type of the object.
 
         Parameters
         ----------
         type_module : str
             The full dotted name of the module the type is defined in, like
             ``numpy``.
         type_name : str
             The name of the type (the class name), like ``dtype``
         func : callable
             A callable for computing the format data.
             `func` will be called with the object to be formatted,
             and will return the raw data in this formatter's format.
             Subclasses may use a different call signature for the
             `func` argument.
             
             If `func` is None or unspecified, there will be no change,
             only returning the current value.
         
         Returns
         -------
         oldfunc : callable
             The currently registered callable.
             If you are registering a new formatter,
             this will be the previous value (to enable restoring later).
         """
         key = (type_module, type_name)
         
         try:
             oldfunc = self.lookup_by_type("%s.%s" % key)
         except KeyError:
             oldfunc = None
         
         if func is not None:
             self.deferred_printers[key] = func
         return oldfunc
     
     def pop(self, typ, default=_raise_key_error):
         """Pop a formatter for the given type.
 
         Parameters
         ----------
         typ : type or '__module__.__name__' string for a type
         default : object
             value to be returned if no formatter is registered for typ.
 
         Returns
         -------
         obj : object
             The last registered object for the type.
 
         Raises
         ------
         KeyError if the type is not registered and default is not specified.
         """
         
         if isinstance(typ, string_types):
             typ_key = tuple(typ.rsplit('.',1))
             if typ_key not in self.deferred_printers:
                 # We may have it cached in the type map. We will have to
                 # iterate over all of the types to check.
                 for cls in self.type_printers:
                     if _mod_name_key(cls) == typ_key:
                         old = self.type_printers.pop(cls)
                         break
                 else:
                     old = default
             else:
                 old = self.deferred_printers.pop(typ_key)
         else:
             if typ in self.type_printers:
                 old = self.type_printers.pop(typ)
             else:
                 old = self.deferred_printers.pop(_mod_name_key(typ), default)
         if old is _raise_key_error:
             raise KeyError("No registered value for {0!r}".format(typ))
         return old
 
     def _in_deferred_types(self, cls):
         """
         Check if the given class is specified in the deferred type registry.
 
         Successful matches will be moved to the regular type registry for future use.
         """
         mod = getattr(cls, '__module__', None)
         name = getattr(cls, '__name__', None)
         key = (mod, name)
         if key in self.deferred_printers:
             # Move the printer over to the regular registry.
             printer = self.deferred_printers.pop(key)
             self.type_printers[cls] = printer
             return True
         return False
 
 
 class PlainTextFormatter(BaseFormatter):
     """The default pretty-printer.
 
     This uses :mod:`IPython.lib.pretty` to compute the format data of
     the object. If the object cannot be pretty printed, :func:`repr` is used.
     See the documentation of :mod:`IPython.lib.pretty` for details on
     how to write pretty printers.  Here is a simple example::
 
         def dtype_pprinter(obj, p, cycle):
             if cycle:
                 return p.text('dtype(...)')
             if hasattr(obj, 'fields'):
                 if obj.fields is None:
                     p.text(repr(obj))
                 else:
                     p.begin_group(7, 'dtype([')
                     for i, field in enumerate(obj.descr):
                         if i > 0:
                             p.text(',')
                             p.breakable()
                         p.pretty(field)
                     p.end_group(7, '])')
     """
 
     # The format type of data returned.
     format_type = Unicode('text/plain')
 
     # This subclass ignores this attribute as it always need to return
     # something.
     enabled = Bool(True).tag(config=False)
     
-    max_seq_length = Integer(pretty.MAX_SEQ_LENGTH).tag(config=True,
+    max_seq_length = Integer(pretty.MAX_SEQ_LENGTH,
         help="""Truncate large collections (lists, dicts, tuples, sets) to this size.
         
         Set to 0 to disable truncation.
         """
-    )
+    ).tag(config=True)
     
     # Look for a _repr_pretty_ methods to use for pretty printing.
     print_method = ObjectName('_repr_pretty_')
 
     # Whether to pretty-print or not.
     pprint = Bool(True).tag(config=True)
 
     # Whether to be verbose or not.
     verbose = Bool(False).tag(config=True)
 
     # The maximum width.
     max_width = Integer(79).tag(config=True)
 
     # The newline character.
     newline = Unicode('\n').tag(config=True)
 
     # format-string for pprinting floats
     float_format = Unicode('%r')
     # setter for float precision, either int or direct format-string
     float_precision = CUnicode('').tag(config=True)
 
     def _float_precision_changed(self, name, old, new):
         """float_precision changed, set float_format accordingly.
 
         float_precision can be set by int or str.
         This will set float_format, after interpreting input.
         If numpy has been imported, numpy print precision will also be set.
 
         integer `n` sets format to '%.nf', otherwise, format set directly.
 
         An empty string returns to defaults (repr for float, 8 for numpy).
 
         This parameter can be set via the '%precision' magic.
         """
 
         if '%' in new:
             # got explicit format string
             fmt = new
             try:
                 fmt%3.14159
             except Exception:
                 raise ValueError("Precision must be int or format string, not %r"%new)
         elif new:
             # otherwise, should be an int
             try:
                 i = int(new)
                 assert i >= 0
             except ValueError:
                 raise ValueError("Precision must be int or format string, not %r"%new)
             except AssertionError:
                 raise ValueError("int precision must be non-negative, not %r"%i)
 
             fmt = '%%.%if'%i
             if 'numpy' in sys.modules:
                 # set numpy precision if it has been imported
                 import numpy
                 numpy.set_printoptions(precision=i)
         else:
             # default back to repr
             fmt = '%r'
             if 'numpy' in sys.modules:
                 import numpy
                 # numpy default is 8
                 numpy.set_printoptions(precision=8)
         self.float_format = fmt
 
     # Use the default pretty printers from IPython.lib.pretty.
+    @default('singleton_printers')
     def _singleton_printers_default(self):
         return pretty._singleton_pprinters.copy()
 
+    @default('type_printers')
     def _type_printers_default(self):
         d = pretty._type_pprinters.copy()
         d[float] = lambda obj,p,cycle: p.text(self.float_format%obj)
         return d
 
+    @default('deferred_printers')
     def _deferred_printers_default(self):
         return pretty._deferred_type_pprinters.copy()
 
     #### FormatterABC interface ####
 
     @catch_format_error
     def __call__(self, obj):
         """Compute the pretty representation of the object."""
         if not self.pprint:
             return repr(obj)
         else:
             # handle str and unicode on Python 2
             # io.StringIO only accepts unicode,
             # cStringIO doesn't handle unicode on py2,
             # StringIO allows str, unicode but only ascii str
             stream = pretty.CUnicodeIO()
             printer = pretty.RepresentationPrinter(stream, self.verbose,
                 self.max_width, self.newline,
                 max_seq_length=self.max_seq_length,
                 singleton_pprinters=self.singleton_printers,
                 type_pprinters=self.type_printers,
                 deferred_pprinters=self.deferred_printers)
             printer.pretty(obj)
             printer.flush()
             return stream.getvalue()
 
 
 class HTMLFormatter(BaseFormatter):
     """An HTML formatter.
 
     To define the callables that compute the HTML representation of your
     objects, define a :meth:`_repr_html_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a valid HTML snippet that
     could be injected into an existing DOM. It should *not* include the
     ```<html>`` or ```<body>`` tags.
     """
     format_type = Unicode('text/html')
 
     print_method = ObjectName('_repr_html_')
 
 
 class MarkdownFormatter(BaseFormatter):
     """A Markdown formatter.
 
     To define the callables that compute the Markdown representation of your
     objects, define a :meth:`_repr_markdown_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a valid Markdown.
     """
     format_type = Unicode('text/markdown')
 
     print_method = ObjectName('_repr_markdown_')
 
 class SVGFormatter(BaseFormatter):
     """An SVG formatter.
 
     To define the callables that compute the SVG representation of your
     objects, define a :meth:`_repr_svg_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be valid SVG enclosed in
     ```<svg>``` tags, that could be injected into an existing DOM. It should
     *not* include the ```<html>`` or ```<body>`` tags.
     """
     format_type = Unicode('image/svg+xml')
 
     print_method = ObjectName('_repr_svg_')
 
 
 class PNGFormatter(BaseFormatter):
     """A PNG formatter.
 
     To define the callables that compute the PNG representation of your
     objects, define a :meth:`_repr_png_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be raw PNG data, *not*
     base64 encoded.
     """
     format_type = Unicode('image/png')
 
     print_method = ObjectName('_repr_png_')
     
     _return_type = (bytes, unicode_type)
 
 
 class JPEGFormatter(BaseFormatter):
     """A JPEG formatter.
 
     To define the callables that compute the JPEG representation of your
     objects, define a :meth:`_repr_jpeg_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be raw JPEG data, *not*
     base64 encoded.
     """
     format_type = Unicode('image/jpeg')
 
     print_method = ObjectName('_repr_jpeg_')
 
     _return_type = (bytes, unicode_type)
 
 
 class LatexFormatter(BaseFormatter):
     """A LaTeX formatter.
 
     To define the callables that compute the LaTeX representation of your
     objects, define a :meth:`_repr_latex_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a valid LaTeX equation,
     enclosed in either ```$```, ```$$``` or another LaTeX equation
     environment.
     """
     format_type = Unicode('text/latex')
 
     print_method = ObjectName('_repr_latex_')
 
 
 class JSONFormatter(BaseFormatter):
     """A JSON string formatter.
 
     To define the callables that compute the JSONable representation of
     your objects, define a :meth:`_repr_json_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a JSONable list or dict.
     JSON scalars (None, number, string) are not allowed, only dict or list containers.
     """
     format_type = Unicode('application/json')
     _return_type = (list, dict)
 
     print_method = ObjectName('_repr_json_')
     
     def _check_return(self, r, obj):
         """Check that a return value is appropriate
         
         Return the value if so, None otherwise, warning if invalid.
         """
         if r is None:
             return
         md = None
         if isinstance(r, tuple):
             # unpack data, metadata tuple for type checking on first element
             r, md = r
         
         # handle deprecated JSON-as-string form from IPython < 3
         if isinstance(r, string_types):
             warnings.warn("JSON expects JSONable list/dict containers, not JSON strings",
             FormatterWarning)
             r = json.loads(r)
         
         if md is not None:
             # put the tuple back together
             r = (r, md)
         return super(JSONFormatter, self)._check_return(r, obj)
 
 
 class JavascriptFormatter(BaseFormatter):
     """A Javascript formatter.
 
     To define the callables that compute the Javascript representation of
     your objects, define a :meth:`_repr_javascript_` method or use the
     :meth:`for_type` or :meth:`for_type_by_name` methods to register functions
     that handle this.
 
     The return value of this formatter should be valid Javascript code and
     should *not* be enclosed in ```<script>``` tags.
     """
     format_type = Unicode('application/javascript')
 
     print_method = ObjectName('_repr_javascript_')
 
 
 class PDFFormatter(BaseFormatter):
     """A PDF formatter.
 
     To define the callables that compute the PDF representation of your
     objects, define a :meth:`_repr_pdf_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be raw PDF data, *not*
     base64 encoded.
     """
     format_type = Unicode('application/pdf')
 
     print_method = ObjectName('_repr_pdf_')
 
     _return_type = (bytes, unicode_type)
 
 class IPythonDisplayFormatter(BaseFormatter):
     """A Formatter for objects that know how to display themselves.
     
     To define the callables that compute the representation of your
     objects, define a :meth:`_ipython_display_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this. Unlike mime-type displays, this method should not return anything,
     instead calling any appropriate display methods itself.
     
     This display formatter has highest priority.
     If it fires, no other display formatter will be called.
     """
     print_method = ObjectName('_ipython_display_')
     _return_type = (type(None), bool)
     
 
     @catch_format_error
     def __call__(self, obj):
         """Compute the format for an object."""
         if self.enabled:
             # lookup registered printer
             try:
                 printer = self.lookup(obj)
             except KeyError:
                 pass
             else:
                 printer(obj)
                 return True
             # Finally look for special method names
             method = get_real_method(obj, self.print_method)
             if method is not None:
                 method()
                 return True
 
 
 FormatterABC.register(BaseFormatter)
 FormatterABC.register(PlainTextFormatter)
 FormatterABC.register(HTMLFormatter)
 FormatterABC.register(MarkdownFormatter)
 FormatterABC.register(SVGFormatter)
 FormatterABC.register(PNGFormatter)
 FormatterABC.register(PDFFormatter)
 FormatterABC.register(JPEGFormatter)
 FormatterABC.register(LatexFormatter)
 FormatterABC.register(JSONFormatter)
 FormatterABC.register(JavascriptFormatter)
 FormatterABC.register(IPythonDisplayFormatter)
 
 
 def format_display_data(obj, include=None, exclude=None):
     """Return a format data dict for an object.
 
     By default all format types will be computed.
 
     The following MIME types are currently implemented:
 
     * text/plain
     * text/html
     * text/markdown
     * text/latex
     * application/json
     * application/javascript
     * application/pdf
     * image/png
     * image/jpeg
     * image/svg+xml
 
     Parameters
     ----------
     obj : object
         The Python object whose format data will be computed.
 
     Returns
     -------
     format_dict : dict
         A dictionary of key/value pairs, one or each format that was
         generated for the object. The keys are the format types, which
         will usually be MIME type strings and the values and JSON'able
         data structure containing the raw data for the representation in
         that format.
     include : list or tuple, optional
         A list of format type strings (MIME types) to include in the
         format data dict. If this is set *only* the format types included
         in this list will be computed.
     exclude : list or tuple, optional
         A list of format type string (MIME types) to exclue in the format
         data dict. If this is set all format types will be computed,
         except for those included in this argument.
     """
     from IPython.core.interactiveshell import InteractiveShell
 
     return InteractiveShell.instance().display_formatter.format(
         obj,
         include,
         exclude
     )
 

IPython/core/history.py

@@ -1,904 +1,908 b''
 """ History related magics and functionality """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 from __future__ import print_function
 
 import atexit
 import datetime
 import os
 import re
 try:
     import sqlite3
 except ImportError:
     try:
         from pysqlite2 import dbapi2 as sqlite3
     except ImportError:
         sqlite3 = None
 import threading
 
 from traitlets.config.configurable import LoggingConfigurable
 from decorator import decorator
 from IPython.utils.decorators import undoc
 from IPython.utils.path import locate_profile
 from IPython.utils import py3compat
 from traitlets import (
     Any, Bool, Dict, Instance, Integer, List, Unicode, TraitError,
+    default, observe,
 )
 from warnings import warn
 
 #-----------------------------------------------------------------------------
 # Classes and functions
 #-----------------------------------------------------------------------------
 
 @undoc
 class DummyDB(object):
     """Dummy DB that will act as a black hole for history.
     
     Only used in the absence of sqlite"""
     def execute(*args, **kwargs):
         return []
     
     def commit(self, *args, **kwargs):
         pass
     
     def __enter__(self, *args, **kwargs):
         pass
     
     def __exit__(self, *args, **kwargs):
         pass
 
 
 @decorator
 def needs_sqlite(f, self, *a, **kw):
     """Decorator: return an empty list in the absence of sqlite."""
     if sqlite3 is None or not self.enabled:
         return []
     else:
         return f(self, *a, **kw)
 
 
 if sqlite3 is not None:
     DatabaseError = sqlite3.DatabaseError
     OperationalError = sqlite3.OperationalError
 else:
     @undoc
     class DatabaseError(Exception):
         "Dummy exception when sqlite could not be imported. Should never occur."
     
     @undoc
     class OperationalError(Exception):
         "Dummy exception when sqlite could not be imported. Should never occur."
 
 # use 16kB as threshold for whether a corrupt history db should be saved
 # that should be at least 100 entries or so
 _SAVE_DB_SIZE = 16384
 
 @decorator
 def catch_corrupt_db(f, self, *a, **kw):
     """A decorator which wraps HistoryAccessor method calls to catch errors from
     a corrupt SQLite database, move the old database out of the way, and create
     a new one.
 
     We avoid clobbering larger databases because this may be triggered due to filesystem issues,
     not just a corrupt file.
     """
     try:
         return f(self, *a, **kw)
     except (DatabaseError, OperationalError) as e:
         self._corrupt_db_counter += 1
         self.log.error("Failed to open SQLite history %s (%s).", self.hist_file, e)
         if self.hist_file != ':memory:':
             if self._corrupt_db_counter > self._corrupt_db_limit:
                 self.hist_file = ':memory:'
                 self.log.error("Failed to load history too many times, history will not be saved.")
             elif os.path.isfile(self.hist_file):
                 # move the file out of the way
                 base, ext = os.path.splitext(self.hist_file)
                 size = os.stat(self.hist_file).st_size
                 if size >= _SAVE_DB_SIZE:
                     # if there's significant content, avoid clobbering
                     now = datetime.datetime.now().isoformat().replace(':', '.')
                     newpath = base + '-corrupt-' + now + ext
                     # don't clobber previous corrupt backups
                     for i in range(100):
                         if not os.path.isfile(newpath):
                             break
                         else:
                             newpath = base + '-corrupt-' + now + (u'-%i' % i) + ext
                 else:
                     # not much content, possibly empty; don't worry about clobbering
                     # maybe we should just delete it?
                     newpath = base + '-corrupt' + ext
                 os.rename(self.hist_file, newpath)
                 self.log.error("History file was moved to %s and a new file created.", newpath)
             self.init_db()
             return []
         else:
             # Failed with :memory:, something serious is wrong
             raise
         
 class HistoryAccessorBase(LoggingConfigurable):
     """An abstract class for History Accessors """
 
     def get_tail(self, n=10, raw=True, output=False, include_latest=False):
         raise NotImplementedError
 
     def search(self, pattern="*", raw=True, search_raw=True,
                output=False, n=None, unique=False):
         raise NotImplementedError
 
     def get_range(self, session, start=1, stop=None, raw=True,output=False):
         raise NotImplementedError
 
     def get_range_by_str(self, rangestr, raw=True, output=False):
         raise NotImplementedError
 
 
 class HistoryAccessor(HistoryAccessorBase):
     """Access the history database without adding to it.
     
     This is intended for use by standalone history tools. IPython shells use
     HistoryManager, below, which is a subclass of this."""
 
     # counter for init_db retries, so we don't keep trying over and over
     _corrupt_db_counter = 0
      # after two failures, fallback on :memory:
     _corrupt_db_limit = 2
 
     # String holding the path to the history file
-    hist_file = Unicode(config=True,
+    hist_file = Unicode(
         help="""Path to file to use for SQLite history database.
         
         By default, IPython will put the history database in the IPython
         profile directory.  If you would rather share one history among
         profiles, you can set this value in each, so that they are consistent.
         
         Due to an issue with fcntl, SQLite is known to misbehave on some NFS
         mounts.  If you see IPython hanging, try setting this to something on a
         local disk, e.g::
         
             ipython --HistoryManager.hist_file=/tmp/ipython_hist.sqlite
         
-        """)
+        """).tag(config=True)
     
-    enabled = Bool(True, config=True,
+    enabled = Bool(True,
         help="""enable the SQLite history
         
         set enabled=False to disable the SQLite history,
         in which case there will be no stored history, no SQLite connection,
         and no background saving thread.  This may be necessary in some
         threaded environments where IPython is embedded.
         """
-    )
+    ).tag(config=True)
     
-    connection_options = Dict(config=True,
+    connection_options = Dict(
         help="""Options for configuring the SQLite connection
         
         These options are passed as keyword args to sqlite3.connect
         when establishing database conenctions.
         """
-    )
+    ).tag(config=True)
 
     # The SQLite database
     db = Any()
-    def _db_changed(self, name, old, new):
+    @observe('db')
+    def _db_changed(self, change):
         """validate the db, since it can be an Instance of two different types"""
+        new = change['new']
         connection_types = (DummyDB,)
         if sqlite3 is not None:
             connection_types = (DummyDB, sqlite3.Connection)
         if not isinstance(new, connection_types):
             msg = "%s.db must be sqlite3 Connection or DummyDB, not %r" % \
                     (self.__class__.__name__, new)
             raise TraitError(msg)
     
     def __init__(self, profile='default', hist_file=u'', **traits):
         """Create a new history accessor.
         
         Parameters
         ----------
         profile : str
           The name of the profile from which to open history.
         hist_file : str
           Path to an SQLite history database stored by IPython. If specified,
           hist_file overrides profile.
         config : :class:`~traitlets.config.loader.Config`
           Config object. hist_file can also be set through this.
         """
         # We need a pointer back to the shell for various tasks.
         super(HistoryAccessor, self).__init__(**traits)
         # defer setting hist_file from kwarg until after init,
         # otherwise the default kwarg value would clobber any value
         # set by config
         if hist_file:
             self.hist_file = hist_file
         
         if self.hist_file == u'':
             # No one has set the hist_file, yet.
             self.hist_file = self._get_hist_file_name(profile)
 
         if sqlite3 is None and self.enabled:
             warn("IPython History requires SQLite, your history will not be saved")
             self.enabled = False
         
         self.init_db()
     
     def _get_hist_file_name(self, profile='default'):
         """Find the history file for the given profile name.
         
         This is overridden by the HistoryManager subclass, to use the shell's
         active profile.
         
         Parameters
         ----------
         profile : str
           The name of a profile which has a history file.
         """
         return os.path.join(locate_profile(profile), 'history.sqlite')
     
     @catch_corrupt_db
     def init_db(self):
         """Connect to the database, and create tables if necessary."""
         if not self.enabled:
             self.db = DummyDB()
             return
         
         # use detect_types so that timestamps return datetime objects
         kwargs = dict(detect_types=sqlite3.PARSE_DECLTYPES|sqlite3.PARSE_COLNAMES)
         kwargs.update(self.connection_options)
         self.db = sqlite3.connect(self.hist_file, **kwargs)
         self.db.execute("""CREATE TABLE IF NOT EXISTS sessions (session integer
                         primary key autoincrement, start timestamp,
                         end timestamp, num_cmds integer, remark text)""")
         self.db.execute("""CREATE TABLE IF NOT EXISTS history
                 (session integer, line integer, source text, source_raw text,
                 PRIMARY KEY (session, line))""")
         # Output history is optional, but ensure the table's there so it can be
         # enabled later.
         self.db.execute("""CREATE TABLE IF NOT EXISTS output_history
                         (session integer, line integer, output text,
                         PRIMARY KEY (session, line))""")
         self.db.commit()
         # success! reset corrupt db count
         self._corrupt_db_counter = 0
 
     def writeout_cache(self):
         """Overridden by HistoryManager to dump the cache before certain
         database lookups."""
         pass
 
     ## -------------------------------
     ## Methods for retrieving history:
     ## -------------------------------
     def _run_sql(self, sql, params, raw=True, output=False):
         """Prepares and runs an SQL query for the history database.
 
         Parameters
         ----------
         sql : str
           Any filtering expressions to go after SELECT ... FROM ...
         params : tuple
           Parameters passed to the SQL query (to replace "?")
         raw, output : bool
           See :meth:`get_range`
 
         Returns
         -------
         Tuples as :meth:`get_range`
         """
         toget = 'source_raw' if raw else 'source'
         sqlfrom = "history"
         if output:
             sqlfrom = "history LEFT JOIN output_history USING (session, line)"
             toget = "history.%s, output_history.output" % toget
         cur = self.db.execute("SELECT session, line, %s FROM %s " %\
                                 (toget, sqlfrom) + sql, params)
         if output:    # Regroup into 3-tuples, and parse JSON
             return ((ses, lin, (inp, out)) for ses, lin, inp, out in cur)
         return cur
 
     @needs_sqlite
     @catch_corrupt_db
     def get_session_info(self, session):
         """Get info about a session.
 
         Parameters
         ----------
 
         session : int
             Session number to retrieve.
 
         Returns
         -------
         
         session_id : int
            Session ID number
         start : datetime
            Timestamp for the start of the session.
         end : datetime
            Timestamp for the end of the session, or None if IPython crashed.
         num_cmds : int
            Number of commands run, or None if IPython crashed.
         remark : unicode
            A manually set description.
         """
         query = "SELECT * from sessions where session == ?"
         return self.db.execute(query, (session,)).fetchone()
 
     @catch_corrupt_db
     def get_last_session_id(self):
         """Get the last session ID currently in the database.
         
         Within IPython, this should be the same as the value stored in
         :attr:`HistoryManager.session_number`.
         """
         for record in self.get_tail(n=1, include_latest=True):
             return record[0]
 
     @catch_corrupt_db
     def get_tail(self, n=10, raw=True, output=False, include_latest=False):
         """Get the last n lines from the history database.
 
         Parameters
         ----------
         n : int
           The number of lines to get
         raw, output : bool
           See :meth:`get_range`
         include_latest : bool
           If False (default), n+1 lines are fetched, and the latest one
           is discarded. This is intended to be used where the function
           is called by a user command, which it should not return.
 
         Returns
         -------
         Tuples as :meth:`get_range`
         """
         self.writeout_cache()
         if not include_latest:
             n += 1
         cur = self._run_sql("ORDER BY session DESC, line DESC LIMIT ?",
                                 (n,), raw=raw, output=output)
         if not include_latest:
             return reversed(list(cur)[1:])
         return reversed(list(cur))
 
     @catch_corrupt_db
     def search(self, pattern="*", raw=True, search_raw=True,
                output=False, n=None, unique=False):
         """Search the database using unix glob-style matching (wildcards
         * and ?).
 
         Parameters
         ----------
         pattern : str
           The wildcarded pattern to match when searching
         search_raw : bool
           If True, search the raw input, otherwise, the parsed input
         raw, output : bool
           See :meth:`get_range`
         n : None or int
           If an integer is given, it defines the limit of
           returned entries.
         unique : bool
           When it is true, return only unique entries.
 
         Returns
         -------
         Tuples as :meth:`get_range`
         """
         tosearch = "source_raw" if search_raw else "source"
         if output:
             tosearch = "history." + tosearch
         self.writeout_cache()
         sqlform = "WHERE %s GLOB ?" % tosearch
         params = (pattern,)
         if unique:
             sqlform += ' GROUP BY {0}'.format(tosearch)
         if n is not None:
             sqlform += " ORDER BY session DESC, line DESC LIMIT ?"
             params += (n,)
         elif unique:
             sqlform += " ORDER BY session, line"
         cur = self._run_sql(sqlform, params, raw=raw, output=output)
         if n is not None:
             return reversed(list(cur))
         return cur
     
     @catch_corrupt_db
     def get_range(self, session, start=1, stop=None, raw=True,output=False):
         """Retrieve input by session.
 
         Parameters
         ----------
         session : int
             Session number to retrieve.
         start : int
             First line to retrieve.
         stop : int
             End of line range (excluded from output itself). If None, retrieve
             to the end of the session.
         raw : bool
             If True, return untranslated input
         output : bool
             If True, attempt to include output. This will be 'real' Python
             objects for the current session, or text reprs from previous
             sessions if db_log_output was enabled at the time. Where no output
             is found, None is used.
 
         Returns
         -------
         entries
           An iterator over the desired lines. Each line is a 3-tuple, either
           (session, line, input) if output is False, or
           (session, line, (input, output)) if output is True.
         """
         if stop:
             lineclause = "line >= ? AND line < ?"
             params = (session, start, stop)
         else:
             lineclause = "line>=?"
             params = (session, start)
 
         return self._run_sql("WHERE session==? AND %s" % lineclause,
                                     params, raw=raw, output=output)
 
     def get_range_by_str(self, rangestr, raw=True, output=False):
         """Get lines of history from a string of ranges, as used by magic
         commands %hist, %save, %macro, etc.
 
         Parameters
         ----------
         rangestr : str
           A string specifying ranges, e.g. "5 ~2/1-4". See
           :func:`magic_history` for full details.
         raw, output : bool
           As :meth:`get_range`
 
         Returns
         -------
         Tuples as :meth:`get_range`
         """
         for sess, s, e in extract_hist_ranges(rangestr):
             for line in self.get_range(sess, s, e, raw=raw, output=output):
                 yield line
 
 
 class HistoryManager(HistoryAccessor):
     """A class to organize all history-related functionality in one place.
     """
     # Public interface
 
     # An instance of the IPython shell we are attached to
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC',
                      allow_none=True)
     # Lists to hold processed and raw history. These start with a blank entry
     # so that we can index them starting from 1
     input_hist_parsed = List([""])
     input_hist_raw = List([""])
     # A list of directories visited during session
     dir_hist = List()
+    @default('dir_hist')
     def _dir_hist_default(self):
         try:
             return [py3compat.getcwd()]
         except OSError:
             return []
 
     # A dict of output history, keyed with ints from the shell's
     # execution count.
     output_hist = Dict()
     # The text/plain repr of outputs.
     output_hist_reprs = Dict()
 
     # The number of the current session in the history database
     session_number = Integer()
     
-    db_log_output = Bool(False, config=True,
+    db_log_output = Bool(False,
         help="Should the history database include output? (default: no)"
-    )
-    db_cache_size = Integer(0, config=True,
+    ).tag(config=True)
+    db_cache_size = Integer(0,
         help="Write to database every x commands (higher values save disk access & power).\n"
         "Values of 1 or less effectively disable caching."
-    )
+    ).tag(config=True)
     # The input and output caches
     db_input_cache = List()
     db_output_cache = List()
     
     # History saving in separate thread
     save_thread = Instance('IPython.core.history.HistorySavingThread',
                            allow_none=True)
     try:               # Event is a function returning an instance of _Event...
         save_flag = Instance(threading._Event, allow_none=True)
     except AttributeError:         # ...until Python 3.3, when it's a class.
         save_flag = Instance(threading.Event, allow_none=True)
     
     # Private interface
     # Variables used to store the three last inputs from the user.  On each new
     # history update, we populate the user's namespace with these, shifted as
     # necessary.
     _i00 = Unicode(u'')
     _i = Unicode(u'')
     _ii = Unicode(u'')
     _iii = Unicode(u'')
 
     # A regex matching all forms of the exit command, so that we don't store
     # them in the history (it's annoying to rewind the first entry and land on
     # an exit call).
     _exit_re = re.compile(r"(exit|quit)(\s*\(.*\))?$")
 
     def __init__(self, shell=None, config=None, **traits):
         """Create a new history manager associated with a shell instance.
         """
         # We need a pointer back to the shell for various tasks.
         super(HistoryManager, self).__init__(shell=shell, config=config,
             **traits)
         self.save_flag = threading.Event()
         self.db_input_cache_lock = threading.Lock()
         self.db_output_cache_lock = threading.Lock()
         
         try:
             self.new_session()
         except OperationalError:
             self.log.error("Failed to create history session in %s. History will not be saved.",
                 self.hist_file, exc_info=True)
             self.hist_file = ':memory:'
         
         if self.enabled and self.hist_file != ':memory:':
             self.save_thread = HistorySavingThread(self)
             self.save_thread.start()
 
     def _get_hist_file_name(self, profile=None):
         """Get default history file name based on the Shell's profile.
         
         The profile parameter is ignored, but must exist for compatibility with
         the parent class."""
         profile_dir = self.shell.profile_dir.location
         return os.path.join(profile_dir, 'history.sqlite')
     
     @needs_sqlite
     def new_session(self, conn=None):
         """Get a new session number."""
         if conn is None:
             conn = self.db
         
         with conn:
             cur = conn.execute("""INSERT INTO sessions VALUES (NULL, ?, NULL,
                             NULL, "") """, (datetime.datetime.now(),))
             self.session_number = cur.lastrowid
             
     def end_session(self):
         """Close the database session, filling in the end time and line count."""
         self.writeout_cache()
         with self.db:
             self.db.execute("""UPDATE sessions SET end=?, num_cmds=? WHERE
                             session==?""", (datetime.datetime.now(),
                             len(self.input_hist_parsed)-1, self.session_number))
         self.session_number = 0
                             
     def name_session(self, name):
         """Give the current session a name in the history database."""
         with self.db:
             self.db.execute("UPDATE sessions SET remark=? WHERE session==?",
                             (name, self.session_number))
                             
     def reset(self, new_session=True):
         """Clear the session history, releasing all object references, and
         optionally open a new session."""
         self.output_hist.clear()
         # The directory history can't be completely empty
         self.dir_hist[:] = [py3compat.getcwd()]
         
         if new_session:
             if self.session_number:
                 self.end_session()
             self.input_hist_parsed[:] = [""]
             self.input_hist_raw[:] = [""]
             self.new_session()
 
     # ------------------------------
     # Methods for retrieving history
     # ------------------------------
     def get_session_info(self, session=0):
         """Get info about a session.
 
         Parameters
         ----------
 
         session : int
             Session number to retrieve. The current session is 0, and negative
             numbers count back from current session, so -1 is the previous session.
 
         Returns
         -------
         
         session_id : int
            Session ID number
         start : datetime
            Timestamp for the start of the session.
         end : datetime
            Timestamp for the end of the session, or None if IPython crashed.
         num_cmds : int
            Number of commands run, or None if IPython crashed.
         remark : unicode
            A manually set description.
         """
         if session <= 0:
             session += self.session_number
 
         return super(HistoryManager, self).get_session_info(session=session)
 
     def _get_range_session(self, start=1, stop=None, raw=True, output=False):
         """Get input and output history from the current session. Called by
         get_range, and takes similar parameters."""
         input_hist = self.input_hist_raw if raw else self.input_hist_parsed
             
         n = len(input_hist)
         if start < 0:
             start += n
         if not stop or (stop > n):
             stop = n
         elif stop < 0:
             stop += n
         
         for i in range(start, stop):
             if output:
                 line = (input_hist[i], self.output_hist_reprs.get(i))
             else:
                 line = input_hist[i]
             yield (0, i, line)
     
     def get_range(self, session=0, start=1, stop=None, raw=True,output=False):
         """Retrieve input by session.
         
         Parameters
         ----------
         session : int
             Session number to retrieve. The current session is 0, and negative
             numbers count back from current session, so -1 is previous session.
         start : int
             First line to retrieve.
         stop : int
             End of line range (excluded from output itself). If None, retrieve
             to the end of the session.
         raw : bool
             If True, return untranslated input
         output : bool
             If True, attempt to include output. This will be 'real' Python
             objects for the current session, or text reprs from previous
             sessions if db_log_output was enabled at the time. Where no output
             is found, None is used.
             
         Returns
         -------
         entries
           An iterator over the desired lines. Each line is a 3-tuple, either
           (session, line, input) if output is False, or
           (session, line, (input, output)) if output is True.
         """
         if session <= 0:
             session += self.session_number
         if session==self.session_number:          # Current session
             return self._get_range_session(start, stop, raw, output)
         return super(HistoryManager, self).get_range(session, start, stop, raw,
                                                      output)
 
     ## ----------------------------
     ## Methods for storing history:
     ## ----------------------------
     def store_inputs(self, line_num, source, source_raw=None):
         """Store source and raw input in history and create input cache
         variables ``_i*``.
 
         Parameters
         ----------
         line_num : int
           The prompt number of this input.
 
         source : str
           Python input.
 
         source_raw : str, optional
           If given, this is the raw input without any IPython transformations
           applied to it.  If not given, ``source`` is used.
         """
         if source_raw is None:
             source_raw = source
         source = source.rstrip('\n')
         source_raw = source_raw.rstrip('\n')
 
         # do not store exit/quit commands
         if self._exit_re.match(source_raw.strip()):
             return
 
         self.input_hist_parsed.append(source)
         self.input_hist_raw.append(source_raw)
 
         with self.db_input_cache_lock:
             self.db_input_cache.append((line_num, source, source_raw))
             # Trigger to flush cache and write to DB.
             if len(self.db_input_cache) >= self.db_cache_size:
                 self.save_flag.set()
 
         # update the auto _i variables
         self._iii = self._ii
         self._ii = self._i
         self._i = self._i00
         self._i00 = source_raw
 
         # hackish access to user namespace to create _i1,_i2... dynamically
         new_i = '_i%s' % line_num
         to_main = {'_i': self._i,
                    '_ii': self._ii,
                    '_iii': self._iii,
                    new_i : self._i00 }
         
         if self.shell is not None:
             self.shell.push(to_main, interactive=False)
 
     def store_output(self, line_num):
         """If database output logging is enabled, this saves all the
         outputs from the indicated prompt number to the database. It's
         called by run_cell after code has been executed.
 
         Parameters
         ----------
         line_num : int
           The line number from which to save outputs
         """
         if (not self.db_log_output) or (line_num not in self.output_hist_reprs):
             return
         output = self.output_hist_reprs[line_num]
 
         with self.db_output_cache_lock:
             self.db_output_cache.append((line_num, output))
         if self.db_cache_size <= 1:
             self.save_flag.set()
 
     def _writeout_input_cache(self, conn):
         with conn:
             for line in self.db_input_cache:
                 conn.execute("INSERT INTO history VALUES (?, ?, ?, ?)",
                                 (self.session_number,)+line)
 
     def _writeout_output_cache(self, conn):
         with conn:
             for line in self.db_output_cache:
                 conn.execute("INSERT INTO output_history VALUES (?, ?, ?)",
                                 (self.session_number,)+line)
 
     @needs_sqlite
     def writeout_cache(self, conn=None):
         """Write any entries in the cache to the database."""
         if conn is None:
             conn = self.db
 
         with self.db_input_cache_lock:
             try:
                 self._writeout_input_cache(conn)
             except sqlite3.IntegrityError:
                 self.new_session(conn)
                 print("ERROR! Session/line number was not unique in",
                       "database. History logging moved to new session",
                                                 self.session_number)
                 try:
                     # Try writing to the new session. If this fails, don't
                     # recurse
                     self._writeout_input_cache(conn)
                 except sqlite3.IntegrityError:
                     pass
             finally:
                 self.db_input_cache = []
 
         with self.db_output_cache_lock:
             try:
                 self._writeout_output_cache(conn)
             except sqlite3.IntegrityError:
                 print("!! Session/line number for output was not unique",
                       "in database. Output will not be stored.")
             finally:
                 self.db_output_cache = []
 
 
 class HistorySavingThread(threading.Thread):
     """This thread takes care of writing history to the database, so that
     the UI isn't held up while that happens.
 
     It waits for the HistoryManager's save_flag to be set, then writes out
     the history cache. The main thread is responsible for setting the flag when
     the cache size reaches a defined threshold."""
     daemon = True
     stop_now = False
     enabled = True
     def __init__(self, history_manager):
         super(HistorySavingThread, self).__init__(name="IPythonHistorySavingThread")
         self.history_manager = history_manager
         self.enabled = history_manager.enabled
         atexit.register(self.stop)
 
     @needs_sqlite
     def run(self):
         # We need a separate db connection per thread:
         try:
             self.db = sqlite3.connect(self.history_manager.hist_file,
                             **self.history_manager.connection_options
             )
             while True:
                 self.history_manager.save_flag.wait()
                 if self.stop_now:
                     self.db.close()
                     return
                 self.history_manager.save_flag.clear()
                 self.history_manager.writeout_cache(self.db)
         except Exception as e:
             print(("The history saving thread hit an unexpected error (%s)."
                    "History will not be written to the database.") % repr(e))
 
     def stop(self):
         """This can be called from the main thread to safely stop this thread.
 
         Note that it does not attempt to write out remaining history before
         exiting. That should be done by calling the HistoryManager's
         end_session method."""
         self.stop_now = True
         self.history_manager.save_flag.set()
         self.join()
 
 
 # To match, e.g. ~5/8-~2/3
 range_re = re.compile(r"""
 ((?P<startsess>~?\d+)/)?
 (?P<start>\d+)?
 ((?P<sep>[\-:])
  ((?P<endsess>~?\d+)/)?
  (?P<end>\d+))?
 $""", re.VERBOSE)
 
 
 def extract_hist_ranges(ranges_str):
     """Turn a string of history ranges into 3-tuples of (session, start, stop).
 
     Examples
     --------
     >>> list(extract_hist_ranges("~8/5-~7/4 2"))
     [(-8, 5, None), (-7, 1, 5), (0, 2, 3)]
     """
     for range_str in ranges_str.split():
         rmatch = range_re.match(range_str)
         if not rmatch:
             continue
         start = rmatch.group("start")
         if start:
             start = int(start)
             end = rmatch.group("end")
             # If no end specified, get (a, a + 1)
             end = int(end) if end else start + 1
         else:  # start not specified
             if not rmatch.group('startsess'):  # no startsess
                 continue
             start = 1
             end = None  # provide the entire session hist
 
         if rmatch.group("sep") == "-":       # 1-3 == 1:4 --> [1, 2, 3]
             end += 1
         startsess = rmatch.group("startsess") or "0"
         endsess = rmatch.group("endsess") or startsess
         startsess = int(startsess.replace("~","-"))
         endsess = int(endsess.replace("~","-"))
         assert endsess >= startsess, "start session must be earlier than end session"
 
         if endsess == startsess:
             yield (startsess, start, end)
             continue
         # Multiple sessions in one range:
         yield (startsess, start, None)
         for sess in range(startsess+1, endsess):
             yield (sess, 1, None)
         yield (endsess, 1, end)
 
 
 def _format_lineno(session, line):
     """Helper function to format line numbers properly."""
     if session == 0:
         return str(line)
     return "%s#%s" % (session, line)

IPython/core/magic.py

@@ -1,703 +1,699 b''
 # encoding: utf-8
 """Magic functions for InteractiveShell.
 """
 from __future__ import print_function
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2001 Janko Hauser <[e-mail]> and
 #  Copyright (C) 2001 Fernando Perez <[e-mail]>
 #  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
-#-----------------------------------------------------------------------------
-# Stdlib
 import os
 import re
 import sys
 import types
 from getopt import getopt, GetoptError
 
-# Our own
 from traitlets.config.configurable import Configurable
 from IPython.core import oinspect
 from IPython.core.error import UsageError
 from IPython.core.inputsplitter import ESC_MAGIC, ESC_MAGIC2
 from decorator import decorator
 from IPython.utils.ipstruct import Struct
 from IPython.utils.process import arg_split
 from IPython.utils.py3compat import string_types, iteritems
 from IPython.utils.text import dedent
-from traitlets import Bool, Dict, Instance
+from traitlets import Bool, Dict, Instance, observe
 from logging import error
 
 #-----------------------------------------------------------------------------
 # Globals
 #-----------------------------------------------------------------------------
 
 # A dict we'll use for each class that has magics, used as temporary storage to
 # pass information between the @line/cell_magic method decorators and the
 # @magics_class class decorator, because the method decorators have no
 # access to the class when they run.  See for more details:
 # http://stackoverflow.com/questions/2366713/can-a-python-decorator-of-an-instance-method-access-the-class
 
 magics = dict(line={}, cell={})
 
 magic_kinds = ('line', 'cell')
 magic_spec = ('line', 'cell', 'line_cell')
 magic_escapes = dict(line=ESC_MAGIC, cell=ESC_MAGIC2)
 
 #-----------------------------------------------------------------------------
 # Utility classes and functions
 #-----------------------------------------------------------------------------
 
 class Bunch: pass
 
 
 def on_off(tag):
     """Return an ON/OFF string for a 1/0 input. Simple utility function."""
     return ['OFF','ON'][tag]
 
 
 def compress_dhist(dh):
     """Compress a directory history into a new one with at most 20 entries.
 
     Return a new list made from the first and last 10 elements of dhist after
     removal of duplicates.
     """
     head, tail = dh[:-10], dh[-10:]
 
     newhead = []
     done = set()
     for h in head:
         if h in done:
             continue
         newhead.append(h)
         done.add(h)
 
     return newhead + tail
 
 
 def needs_local_scope(func):
     """Decorator to mark magic functions which need to local scope to run."""
     func.needs_local_scope = True
     return func
 
 #-----------------------------------------------------------------------------
 # Class and method decorators for registering magics
 #-----------------------------------------------------------------------------
 
 def magics_class(cls):
     """Class decorator for all subclasses of the main Magics class.
 
     Any class that subclasses Magics *must* also apply this decorator, to
     ensure that all the methods that have been decorated as line/cell magics
     get correctly registered in the class instance.  This is necessary because
     when method decorators run, the class does not exist yet, so they
     temporarily store their information into a module global.  Application of
     this class decorator copies that global data to the class instance and
     clears the global.
 
     Obviously, this mechanism is not thread-safe, which means that the
     *creation* of subclasses of Magic should only be done in a single-thread
     context.  Instantiation of the classes has no restrictions.  Given that
     these classes are typically created at IPython startup time and before user
     application code becomes active, in practice this should not pose any
     problems.
     """
     cls.registered = True
     cls.magics = dict(line = magics['line'],
                       cell = magics['cell'])
     magics['line'] = {}
     magics['cell'] = {}
     return cls
 
 
 def record_magic(dct, magic_kind, magic_name, func):
     """Utility function to store a function as a magic of a specific kind.
 
     Parameters
     ----------
     dct : dict
       A dictionary with 'line' and 'cell' subdicts.
 
     magic_kind : str
       Kind of magic to be stored.
 
     magic_name : str
       Key to store the magic as.
 
     func : function
       Callable object to store.
     """
     if magic_kind == 'line_cell':
         dct['line'][magic_name] = dct['cell'][magic_name] = func
     else:
         dct[magic_kind][magic_name] = func
 
 
 def validate_type(magic_kind):
     """Ensure that the given magic_kind is valid.
 
     Check that the given magic_kind is one of the accepted spec types (stored
     in the global `magic_spec`), raise ValueError otherwise.
     """
     if magic_kind not in magic_spec:
         raise ValueError('magic_kind must be one of %s, %s given' %
                          magic_kinds, magic_kind)
 
 
 # The docstrings for the decorator below will be fairly similar for the two
 # types (method and function), so we generate them here once and reuse the
 # templates below.
 _docstring_template = \
 """Decorate the given {0} as {1} magic.
 
 The decorator can be used with or without arguments, as follows.
 
 i) without arguments: it will create a {1} magic named as the {0} being
 decorated::
 
     @deco
     def foo(...)
 
 will create a {1} magic named `foo`.
 
 ii) with one string argument: which will be used as the actual name of the
 resulting magic::
 
     @deco('bar')
     def foo(...)
 
 will create a {1} magic named `bar`.
 """
 
 # These two are decorator factories.  While they are conceptually very similar,
 # there are enough differences in the details that it's simpler to have them
 # written as completely standalone functions rather than trying to share code
 # and make a single one with convoluted logic.
 
 def _method_magic_marker(magic_kind):
     """Decorator factory for methods in Magics subclasses.
     """
 
     validate_type(magic_kind)
 
     # This is a closure to capture the magic_kind.  We could also use a class,
     # but it's overkill for just that one bit of state.
     def magic_deco(arg):
         call = lambda f, *a, **k: f(*a, **k)
 
         if callable(arg):
             # "Naked" decorator call (just @foo, no args)
             func = arg
             name = func.__name__
             retval = decorator(call, func)
             record_magic(magics, magic_kind, name, name)
         elif isinstance(arg, string_types):
             # Decorator called with arguments (@foo('bar'))
             name = arg
             def mark(func, *a, **kw):
                 record_magic(magics, magic_kind, name, func.__name__)
                 return decorator(call, func)
             retval = mark
         else:
             raise TypeError("Decorator can only be called with "
                             "string or function")
         return retval
 
     # Ensure the resulting decorator has a usable docstring
     magic_deco.__doc__ = _docstring_template.format('method', magic_kind)
     return magic_deco
 
 
 def _function_magic_marker(magic_kind):
     """Decorator factory for standalone functions.
     """
     validate_type(magic_kind)
     
     # This is a closure to capture the magic_kind.  We could also use a class,
     # but it's overkill for just that one bit of state.
     def magic_deco(arg):
         call = lambda f, *a, **k: f(*a, **k)
 
         # Find get_ipython() in the caller's namespace
         caller = sys._getframe(1)
         for ns in ['f_locals', 'f_globals', 'f_builtins']:
             get_ipython = getattr(caller, ns).get('get_ipython')
             if get_ipython is not None:
                 break
         else:
             raise NameError('Decorator can only run in context where '
                             '`get_ipython` exists')
 
         ip = get_ipython()
 
         if callable(arg):
             # "Naked" decorator call (just @foo, no args)
             func = arg
             name = func.__name__
             ip.register_magic_function(func, magic_kind, name)
             retval = decorator(call, func)
         elif isinstance(arg, string_types):
             # Decorator called with arguments (@foo('bar'))
             name = arg
             def mark(func, *a, **kw):
                 ip.register_magic_function(func, magic_kind, name)
                 return decorator(call, func)
             retval = mark
         else:
             raise TypeError("Decorator can only be called with "
                              "string or function")
         return retval
 
     # Ensure the resulting decorator has a usable docstring
     ds = _docstring_template.format('function', magic_kind)
 
     ds += dedent("""
     Note: this decorator can only be used in a context where IPython is already
     active, so that the `get_ipython()` call succeeds.  You can therefore use
     it in your startup files loaded after IPython initializes, but *not* in the
     IPython configuration file itself, which is executed before IPython is
     fully up and running.  Any file located in the `startup` subdirectory of
     your configuration profile will be OK in this sense.
     """)
     
     magic_deco.__doc__ = ds
     return magic_deco
 
 
 # Create the actual decorators for public use
 
 # These three are used to decorate methods in class definitions
 line_magic = _method_magic_marker('line')
 cell_magic = _method_magic_marker('cell')
 line_cell_magic = _method_magic_marker('line_cell')
 
 # These three decorate standalone functions and perform the decoration
 # immediately.  They can only run where get_ipython() works
 register_line_magic = _function_magic_marker('line')
 register_cell_magic = _function_magic_marker('cell')
 register_line_cell_magic = _function_magic_marker('line_cell')
 
 #-----------------------------------------------------------------------------
 # Core Magic classes
 #-----------------------------------------------------------------------------
 
 class MagicsManager(Configurable):
     """Object that handles all magic-related functionality for IPython.
     """
     # Non-configurable class attributes
 
     # A two-level dict, first keyed by magic type, then by magic function, and
     # holding the actual callable object as value.  This is the dict used for
     # magic function dispatch
     magics = Dict()
 
     # A registry of the original objects that we've been given holding magics.
     registry = Dict()
 
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
 
-    auto_magic = Bool(True, config=True, help=
-        "Automatically call line magics without requiring explicit % prefix")
-
-    def _auto_magic_changed(self, name, value):
-        self.shell.automagic = value
+    auto_magic = Bool(True, help=
+        "Automatically call line magics without requiring explicit % prefix"
+    ).tag(config=True)
+    @observe('auto_magic')
+    def _auto_magic_changed(self, change):
+        self.shell.automagic = change['new']
     
     _auto_status = [
         'Automagic is OFF, % prefix IS needed for line magics.',
         'Automagic is ON, % prefix IS NOT needed for line magics.']
 
     user_magics = Instance('IPython.core.magics.UserMagics', allow_none=True)
 
     def __init__(self, shell=None, config=None, user_magics=None, **traits):
 
         super(MagicsManager, self).__init__(shell=shell, config=config,
                                            user_magics=user_magics, **traits)
         self.magics = dict(line={}, cell={})
         # Let's add the user_magics to the registry for uniformity, so *all*
         # registered magic containers can be found there.
         self.registry[user_magics.__class__.__name__] = user_magics
 
     def auto_status(self):
         """Return descriptive string with automagic status."""
         return self._auto_status[self.auto_magic]
     
     def lsmagic(self):
         """Return a dict of currently available magic functions.
 
         The return dict has the keys 'line' and 'cell', corresponding to the
         two types of magics we support.  Each value is a list of names.
         """
         return self.magics
 
     def lsmagic_docs(self, brief=False, missing=''):
         """Return dict of documentation of magic functions.
 
         The return dict has the keys 'line' and 'cell', corresponding to the
         two types of magics we support. Each value is a dict keyed by magic
         name whose value is the function docstring. If a docstring is
         unavailable, the value of `missing` is used instead.
 
         If brief is True, only the first line of each docstring will be returned.
         """
         docs = {}
         for m_type in self.magics:
             m_docs = {}
             for m_name, m_func in iteritems(self.magics[m_type]):
                 if m_func.__doc__:
                     if brief:
                         m_docs[m_name] = m_func.__doc__.split('\n', 1)[0]
                     else:
                         m_docs[m_name] = m_func.__doc__.rstrip()
                 else:
                     m_docs[m_name] = missing
             docs[m_type] = m_docs
         return docs
 
     def register(self, *magic_objects):
         """Register one or more instances of Magics.
 
         Take one or more classes or instances of classes that subclass the main 
         `core.Magic` class, and register them with IPython to use the magic
         functions they provide.  The registration process will then ensure that
         any methods that have decorated to provide line and/or cell magics will
         be recognized with the `%x`/`%%x` syntax as a line/cell magic
         respectively.
 
         If classes are given, they will be instantiated with the default
         constructor.  If your classes need a custom constructor, you should
         instanitate them first and pass the instance.
 
         The provided arguments can be an arbitrary mix of classes and instances.
 
         Parameters
         ----------
         magic_objects : one or more classes or instances
         """
         # Start by validating them to ensure they have all had their magic
         # methods registered at the instance level
         for m in magic_objects:
             if not m.registered:
                 raise ValueError("Class of magics %r was constructed without "
                                  "the @register_magics class decorator")
             if isinstance(m, type):
                 # If we're given an uninstantiated class
                 m = m(shell=self.shell)
 
             # Now that we have an instance, we can register it and update the
             # table of callables
             self.registry[m.__class__.__name__] = m
             for mtype in magic_kinds:
                 self.magics[mtype].update(m.magics[mtype])
 
     def register_function(self, func, magic_kind='line', magic_name=None):
         """Expose a standalone function as magic function for IPython.
 
         This will create an IPython magic (line, cell or both) from a
         standalone function.  The functions should have the following
         signatures: 
 
         * For line magics: `def f(line)`
         * For cell magics: `def f(line, cell)`
         * For a function that does both: `def f(line, cell=None)`
 
         In the latter case, the function will be called with `cell==None` when
         invoked as `%f`, and with cell as a string when invoked as `%%f`.
 
         Parameters
         ----------
         func : callable
           Function to be registered as a magic.
 
         magic_kind : str
           Kind of magic, one of 'line', 'cell' or 'line_cell'
 
         magic_name : optional str
           If given, the name the magic will have in the IPython namespace.  By
           default, the name of the function itself is used.
         """
 
         # Create the new method in the user_magics and register it in the
         # global table
         validate_type(magic_kind)
         magic_name = func.__name__ if magic_name is None else magic_name
         setattr(self.user_magics, magic_name, func)
         record_magic(self.magics, magic_kind, magic_name, func)
 
     def define_magic(self, name, func):
         """[Deprecated] Expose own function as magic function for IPython.
 
         Will be removed in IPython 5.0
 
         Example::
 
             def foo_impl(self, parameter_s=''):
                 'My very own magic!. (Use docstrings, IPython reads them).'
                 print 'Magic function. Passed parameter is between < >:'
                 print '<%s>' % parameter_s
                 print 'The self object is:', self
 
             ip.define_magic('foo',foo_impl)
         """
         meth = types.MethodType(func, self.user_magics)
         setattr(self.user_magics, name, meth)
         record_magic(self.magics, 'line', name, meth)
 
     def register_alias(self, alias_name, magic_name, magic_kind='line'):
         """Register an alias to a magic function.
 
         The alias is an instance of :class:`MagicAlias`, which holds the
         name and kind of the magic it should call. Binding is done at
         call time, so if the underlying magic function is changed the alias
         will call the new function.
 
         Parameters
         ----------
         alias_name : str
           The name of the magic to be registered.
 
         magic_name : str
           The name of an existing magic.
 
         magic_kind : str
           Kind of magic, one of 'line' or 'cell'
         """
 
         # `validate_type` is too permissive, as it allows 'line_cell'
         # which we do not handle.
         if magic_kind not in magic_kinds:
             raise ValueError('magic_kind must be one of %s, %s given' %
                              magic_kinds, magic_kind)
 
         alias = MagicAlias(self.shell, magic_name, magic_kind)
         setattr(self.user_magics, alias_name, alias)
         record_magic(self.magics, magic_kind, alias_name, alias)
 
 # Key base class that provides the central functionality for magics.
 
 
 class Magics(Configurable):
     """Base class for implementing magic functions.
 
     Shell functions which can be reached as %function_name. All magic
     functions should accept a string, which they can parse for their own
     needs. This can make some functions easier to type, eg `%cd ../`
     vs. `%cd("../")`
 
     Classes providing magic functions need to subclass this class, and they
     MUST:
 
     - Use the method decorators `@line_magic` and `@cell_magic` to decorate
       individual methods as magic functions, AND
 
     - Use the class decorator `@magics_class` to ensure that the magic
       methods are properly registered at the instance level upon instance
       initialization.
 
     See :mod:`magic_functions` for examples of actual implementation classes.
     """
     # Dict holding all command-line options for each magic.
     options_table = None
     # Dict for the mapping of magic names to methods, set by class decorator
     magics = None
     # Flag to check that the class decorator was properly applied
     registered = False
     # Instance of IPython shell
     shell = None
 
     def __init__(self, shell=None, **kwargs):
         if not(self.__class__.registered):
             raise ValueError('Magics subclass without registration - '
                              'did you forget to apply @magics_class?')
         if shell is not None:
             if hasattr(shell, 'configurables'):
                 shell.configurables.append(self)
             if hasattr(shell, 'config'):
                 kwargs.setdefault('parent', shell)
 
         self.shell = shell
         self.options_table = {}
         # The method decorators are run when the instance doesn't exist yet, so
         # they can only record the names of the methods they are supposed to
         # grab.  Only now, that the instance exists, can we create the proper
         # mapping to bound methods.  So we read the info off the original names
         # table and replace each method name by the actual bound method.
         # But we mustn't clobber the *class* mapping, in case of multiple instances.
         class_magics = self.magics
         self.magics = {}
         for mtype in magic_kinds:
             tab = self.magics[mtype] = {}
             cls_tab = class_magics[mtype]
             for magic_name, meth_name in iteritems(cls_tab):
                 if isinstance(meth_name, string_types):
                     # it's a method name, grab it
                     tab[magic_name] = getattr(self, meth_name)
                 else:
                     # it's the real thing
                     tab[magic_name] = meth_name
         # Configurable **needs** to be initiated at the end or the config
         # magics get screwed up.
         super(Magics, self).__init__(**kwargs)
 
     def arg_err(self,func):
         """Print docstring if incorrect arguments were passed"""
         print('Error in arguments:')
         print(oinspect.getdoc(func))
 
     def format_latex(self, strng):
         """Format a string for latex inclusion."""
 
         # Characters that need to be escaped for latex:
         escape_re = re.compile(r'(%|_|\$|#|&)',re.MULTILINE)
         # Magic command names as headers:
         cmd_name_re = re.compile(r'^(%s.*?):' % ESC_MAGIC,
                                  re.MULTILINE)
         # Magic commands
         cmd_re = re.compile(r'(?P<cmd>%s.+?\b)(?!\}\}:)' % ESC_MAGIC,
                             re.MULTILINE)
         # Paragraph continue
         par_re = re.compile(r'\\$',re.MULTILINE)
 
         # The "\n" symbol
         newline_re = re.compile(r'\\n')
 
         # Now build the string for output:
         #strng = cmd_name_re.sub(r'\n\\texttt{\\textsl{\\large \1}}:',strng)
         strng = cmd_name_re.sub(r'\n\\bigskip\n\\texttt{\\textbf{ \1}}:',
                                 strng)
         strng = cmd_re.sub(r'\\texttt{\g<cmd>}',strng)
         strng = par_re.sub(r'\\\\',strng)
         strng = escape_re.sub(r'\\\1',strng)
         strng = newline_re.sub(r'\\textbackslash{}n',strng)
         return strng
 
     def parse_options(self, arg_str, opt_str, *long_opts, **kw):
         """Parse options passed to an argument string.
 
         The interface is similar to that of :func:`getopt.getopt`, but it
         returns a :class:`~IPython.utils.struct.Struct` with the options as keys
         and the stripped argument string still as a string.
 
         arg_str is quoted as a true sys.argv vector by using shlex.split.
         This allows us to easily expand variables, glob files, quote
         arguments, etc.
 
         Parameters
         ----------
 
         arg_str : str
           The arguments to parse.
 
         opt_str : str
           The options specification.
 
         mode : str, default 'string'
           If given as 'list', the argument string is returned as a list (split
           on whitespace) instead of a string.
 
         list_all : bool, default False
           Put all option values in lists. Normally only options
           appearing more than once are put in a list.
 
         posix : bool, default True
           Whether to split the input line in POSIX mode or not, as per the
           conventions outlined in the :mod:`shlex` module from the standard
           library.
         """
 
         # inject default options at the beginning of the input line
         caller = sys._getframe(1).f_code.co_name
         arg_str = '%s %s' % (self.options_table.get(caller,''),arg_str)
 
         mode = kw.get('mode','string')
         if mode not in ['string','list']:
             raise ValueError('incorrect mode given: %s' % mode)
         # Get options
         list_all = kw.get('list_all',0)
         posix = kw.get('posix', os.name == 'posix')
         strict = kw.get('strict', True)
 
         # Check if we have more than one argument to warrant extra processing:
         odict = {}  # Dictionary with options
         args = arg_str.split()
         if len(args) >= 1:
             # If the list of inputs only has 0 or 1 thing in it, there's no
             # need to look for options
             argv = arg_split(arg_str, posix, strict)
             # Do regular option processing
             try:
                 opts,args = getopt(argv, opt_str, long_opts)
             except GetoptError as e:
                 raise UsageError('%s ( allowed: "%s" %s)' % (e.msg,opt_str,
                                         " ".join(long_opts)))
             for o,a in opts:
                 if o.startswith('--'):
                     o = o[2:]
                 else:
                     o = o[1:]
                 try:
                     odict[o].append(a)
                 except AttributeError:
                     odict[o] = [odict[o],a]
                 except KeyError:
                     if list_all:
                         odict[o] = [a]
                     else:
                         odict[o] = a
 
         # Prepare opts,args for return
         opts = Struct(odict)
         if mode == 'string':
             args = ' '.join(args)
 
         return opts,args
 
     def default_option(self, fn, optstr):
         """Make an entry in the options_table for fn, with value optstr"""
 
         if fn not in self.lsmagic():
             error("%s is not a magic function" % fn)
         self.options_table[fn] = optstr
 
 
 class MagicAlias(object):
     """An alias to another magic function.
 
     An alias is determined by its magic name and magic kind. Lookup
     is done at call time, so if the underlying magic changes the alias
     will call the new function.
 
     Use the :meth:`MagicsManager.register_alias` method or the
     `%alias_magic` magic function to create and register a new alias.
     """
     def __init__(self, shell, magic_name, magic_kind):
         self.shell = shell
         self.magic_name = magic_name
         self.magic_kind = magic_kind
 
         self.pretty_target = '%s%s' % (magic_escapes[self.magic_kind], self.magic_name)
         self.__doc__ = "Alias for `%s`." % self.pretty_target
 
         self._in_call = False
 
     def __call__(self, *args, **kwargs):
         """Call the magic alias."""
         fn = self.shell.find_magic(self.magic_name, self.magic_kind)
         if fn is None:
             raise UsageError("Magic `%s` not found." % self.pretty_target)
 
         # Protect against infinite recursion.
         if self._in_call:
             raise UsageError("Infinite recursion detected; "
                              "magic aliases cannot call themselves.")
         self._in_call = True
         try:
             return fn(*args, **kwargs)
         finally:
             self._in_call = False

IPython/core/magics/script.py

@@ -1,282 +1,272 b''
 """Magic functions for running cells in various scripts."""
 from __future__ import print_function
-#-----------------------------------------------------------------------------
-#  Copyright (c) 2012 The 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
-#-----------------------------------------------------------------------------
+# Copyright (c) IPython Development Team.
+# Distributed under the terms of the Modified BSD License.
 
-# Stdlib
 import errno
 import os
 import sys
 import signal
 import time
 from subprocess import Popen, PIPE
 import atexit
 
-# Our own packages
-from traitlets.config.configurable import Configurable
 from IPython.core import magic_arguments
 from IPython.core.magic import  (
     Magics, magics_class, line_magic, cell_magic
 )
 from IPython.lib.backgroundjobs import BackgroundJobManager
 from IPython.utils import py3compat
 from IPython.utils.process import arg_split
-from traitlets import List, Dict
+from traitlets import List, Dict, default
 
 #-----------------------------------------------------------------------------
 # Magic implementation classes
 #-----------------------------------------------------------------------------
 
 def script_args(f):
     """single decorator for adding script args"""
     args = [
         magic_arguments.argument(
             '--out', type=str,
             help="""The variable in which to store stdout from the script.
             If the script is backgrounded, this will be the stdout *pipe*,
             instead of the stderr text itself.
             """
         ),
         magic_arguments.argument(
             '--err', type=str,
             help="""The variable in which to store stderr from the script.
             If the script is backgrounded, this will be the stderr *pipe*,
             instead of the stderr text itself.
             """
         ),
         magic_arguments.argument(
             '--bg', action="store_true",
             help="""Whether to run the script in the background.
             If given, the only way to see the output of the command is
             with --out/err.
             """
         ),
         magic_arguments.argument(
             '--proc', type=str,
             help="""The variable in which to store Popen instance.
             This is used only when --bg option is given.
             """
         ),
     ]
     for arg in args:
         f = arg(f)
     return f
 
 @magics_class
 class ScriptMagics(Magics):
     """Magics for talking to scripts
     
     This defines a base `%%script` cell magic for running a cell
     with a program in a subprocess, and registers a few top-level
     magics that call %%script with common interpreters.
     """
-    script_magics = List(config=True,
+    script_magics = List(
         help="""Extra script cell magics to define
         
         This generates simple wrappers of `%%script foo` as `%%foo`.
         
         If you want to add script magics that aren't on your path,
         specify them in script_paths
         """,
-    )
+    ).tag(config=True)
+    @default('script_magics')
     def _script_magics_default(self):
         """default to a common list of programs"""
         
         defaults = [
             'sh',
             'bash',
             'perl',
             'ruby',
             'python',
             'python2',
             'python3',
             'pypy',
         ]
         if os.name == 'nt':
             defaults.extend([
                 'cmd',
             ])
         
         return defaults
     
-    script_paths = Dict(config=True,
+    script_paths = Dict(
         help="""Dict mapping short 'ruby' names to full paths, such as '/opt/secret/bin/ruby'
         
         Only necessary for items in script_magics where the default path will not
         find the right interpreter.
         """
-    )
+    ).tag(config=True)
     
     def __init__(self, shell=None):
         super(ScriptMagics, self).__init__(shell=shell)
         self._generate_script_magics()
         self.job_manager = BackgroundJobManager()
         self.bg_processes = []
         atexit.register(self.kill_bg_processes)
 
     def __del__(self):
         self.kill_bg_processes()
     
     def _generate_script_magics(self):
         cell_magics = self.magics['cell']
         for name in self.script_magics:
             cell_magics[name] = self._make_script_magic(name)
     
     def _make_script_magic(self, name):
         """make a named magic, that calls %%script with a particular program"""
         # expand to explicit path if necessary:
         script = self.script_paths.get(name, name)
         
         @magic_arguments.magic_arguments()
         @script_args
         def named_script_magic(line, cell):
             # if line, add it as cl-flags
             if line:
                  line = "%s %s" % (script, line)
             else:
                 line = script
             return self.shebang(line, cell)
         
         # write a basic docstring:
         named_script_magic.__doc__ = \
         """%%{name} script magic
         
         Run cells with {script} in a subprocess.
         
         This is a shortcut for `%%script {script}`
         """.format(**locals())
         
         return named_script_magic
     
     @magic_arguments.magic_arguments()
     @script_args
     @cell_magic("script")
     def shebang(self, line, cell):
         """Run a cell via a shell command
         
         The `%%script` line is like the #! line of script,
         specifying a program (bash, perl, ruby, etc.) with which to run.
         
         The rest of the cell is run by that program.
         
         Examples
         --------
         ::
         
             In [1]: %%script bash
                ...: for i in 1 2 3; do
                ...:   echo $i
                ...: done
             1
             2
             3
         """
         argv = arg_split(line, posix = not sys.platform.startswith('win'))
         args, cmd = self.shebang.parser.parse_known_args(argv)
         
         try:
             p = Popen(cmd, stdout=PIPE, stderr=PIPE, stdin=PIPE)
         except OSError as e:
             if e.errno == errno.ENOENT:
                 print("Couldn't find program: %r" % cmd[0])
                 return
             else:
                 raise
         
         if not cell.endswith('\n'):
             cell += '\n'
         cell = cell.encode('utf8', 'replace')
         if args.bg:
             self.bg_processes.append(p)
             self._gc_bg_processes()
             if args.out:
                 self.shell.user_ns[args.out] = p.stdout
             if args.err:
                 self.shell.user_ns[args.err] = p.stderr
             self.job_manager.new(self._run_script, p, cell, daemon=True)
             if args.proc:
                 self.shell.user_ns[args.proc] = p
             return
         
         try:
             out, err = p.communicate(cell)
         except KeyboardInterrupt:
             try:
                 p.send_signal(signal.SIGINT)
                 time.sleep(0.1)
                 if p.poll() is not None:
                     print("Process is interrupted.")
                     return
                 p.terminate()
                 time.sleep(0.1)
                 if p.poll() is not None:
                     print("Process is terminated.")
                     return
                 p.kill()
                 print("Process is killed.")
             except OSError:
                 pass
             except Exception as e:
                 print("Error while terminating subprocess (pid=%i): %s" \
                     % (p.pid, e))
             return
         out = py3compat.bytes_to_str(out)
         err = py3compat.bytes_to_str(err)
         if args.out:
             self.shell.user_ns[args.out] = out
         else:
             sys.stdout.write(out)
             sys.stdout.flush()
         if args.err:
             self.shell.user_ns[args.err] = err
         else:
             sys.stderr.write(err)
             sys.stderr.flush()
     
     def _run_script(self, p, cell):
         """callback for running the script in the background"""
         p.stdin.write(cell)
         p.stdin.close()
         p.wait()
 
     @line_magic("killbgscripts")
     def killbgscripts(self, _nouse_=''):
         """Kill all BG processes started by %%script and its family."""
         self.kill_bg_processes()
         print("All background processes were killed.")
 
     def kill_bg_processes(self):
         """Kill all BG processes which are still running."""
         for p in self.bg_processes:
             if p.poll() is None:
                 try:
                     p.send_signal(signal.SIGINT)
                 except:
                     pass
         time.sleep(0.1)
         for p in self.bg_processes:
             if p.poll() is None:
                 try:
                     p.terminate()
                 except:
                     pass
         time.sleep(0.1)
         for p in self.bg_processes:
             if p.poll() is None:
                 try:
                     p.kill()
                 except:
                     pass
         self._gc_bg_processes()
 
     def _gc_bg_processes(self):
         self.bg_processes = [p for p in self.bg_processes if p.poll() is None]

IPython/core/prefilter.py

@@ -1,715 +1,700 b''
 # encoding: utf-8
 """
 Prefiltering components.
 
 Prefilters transform user input before it is exec'd by Python.  These
 transforms are used to implement additional syntax such as !ls and %magic.
-
-Authors:
-
-* Brian Granger
-* Fernando Perez
-* Dan Milstein
-* Ville Vainio
 """
 
-#-----------------------------------------------------------------------------
-#  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
-#-----------------------------------------------------------------------------
+# Copyright (c) IPython Development Team.
+# Distributed under the terms of the Modified BSD License.
 
 from keyword import iskeyword
 import re
 
 from IPython.core.autocall import IPyAutocall
 from traitlets.config.configurable import Configurable
 from IPython.core.inputsplitter import (
     ESC_MAGIC,
     ESC_QUOTE,
     ESC_QUOTE2,
     ESC_PAREN,
 )
 from IPython.core.macro import Macro
 from IPython.core.splitinput import LineInfo
 
 from traitlets import (
-    List, Integer, Unicode, CBool, Bool, Instance, CRegExp
+    List, Integer, Unicode, Bool, Instance, CRegExp
 )
 
 #-----------------------------------------------------------------------------
 # Global utilities, errors and constants
 #-----------------------------------------------------------------------------
 
 
 class PrefilterError(Exception):
     pass
 
 
 # RegExp to identify potential function names
 re_fun_name = re.compile(r'[a-zA-Z_]([a-zA-Z0-9_.]*) *$')
 
 # RegExp to exclude strings with this start from autocalling.  In
 # particular, all binary operators should be excluded, so that if foo is
 # callable, foo OP bar doesn't become foo(OP bar), which is invalid.  The
 # characters '!=()' don't need to be checked for, as the checkPythonChars
 # routine explicitely does so, to catch direct calls and rebindings of
 # existing names.
 
 # Warning: the '-' HAS TO BE AT THE END of the first group, otherwise
 # it affects the rest of the group in square brackets.
 re_exclude_auto = re.compile(r'^[,&^\|\*/\+-]'
                              r'|^is |^not |^in |^and |^or ')
 
 # try to catch also methods for stuff in lists/tuples/dicts: off
 # (experimental). For this to work, the line_split regexp would need
 # to be modified so it wouldn't break things at '['. That line is
 # nasty enough that I shouldn't change it until I can test it _well_.
 #self.re_fun_name = re.compile (r'[a-zA-Z_]([a-zA-Z0-9_.\[\]]*) ?$')
 
 
 # Handler Check Utilities
 def is_shadowed(identifier, ip):
     """Is the given identifier defined in one of the namespaces which shadow
     the alias and magic namespaces?  Note that an identifier is different
     than ifun, because it can not contain a '.' character."""
     # This is much safer than calling ofind, which can change state
     return (identifier in ip.user_ns \
             or identifier in ip.user_global_ns \
             or identifier in ip.ns_table['builtin']\
             or iskeyword(identifier))
 
 
 #-----------------------------------------------------------------------------
 # Main Prefilter manager
 #-----------------------------------------------------------------------------
 
 
 class PrefilterManager(Configurable):
     """Main prefilter component.
 
     The IPython prefilter is run on all user input before it is run.  The
     prefilter consumes lines of input and produces transformed lines of
     input.
 
     The iplementation consists of two phases:
 
     1. Transformers
     2. Checkers and handlers
 
     Over time, we plan on deprecating the checkers and handlers and doing
     everything in the transformers.
 
     The transformers are instances of :class:`PrefilterTransformer` and have
     a single method :meth:`transform` that takes a line and returns a
     transformed line.  The transformation can be accomplished using any
     tool, but our current ones use regular expressions for speed.
 
     After all the transformers have been run, the line is fed to the checkers,
     which are instances of :class:`PrefilterChecker`.  The line is passed to
     the :meth:`check` method, which either returns `None` or a
     :class:`PrefilterHandler` instance.  If `None` is returned, the other
     checkers are tried.  If an :class:`PrefilterHandler` instance is returned,
     the line is passed to the :meth:`handle` method of the returned
     handler and no further checkers are tried.
 
     Both transformers and checkers have a `priority` attribute, that determines
     the order in which they are called.  Smaller priorities are tried first.
 
     Both transformers and checkers also have `enabled` attribute, which is
     a boolean that determines if the instance is used.
 
     Users or developers can change the priority or enabled attribute of
     transformers or checkers, but they must call the :meth:`sort_checkers`
     or :meth:`sort_transformers` method after changing the priority.
     """
 
-    multi_line_specials = CBool(True).tag(config=True)
+    multi_line_specials = Bool(True).tag(config=True)
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
 
     def __init__(self, shell=None, **kwargs):
         super(PrefilterManager, self).__init__(shell=shell, **kwargs)
         self.shell = shell
         self.init_transformers()
         self.init_handlers()
         self.init_checkers()
 
     #-------------------------------------------------------------------------
     # API for managing transformers
     #-------------------------------------------------------------------------
 
     def init_transformers(self):
         """Create the default transformers."""
         self._transformers = []
         for transformer_cls in _default_transformers:
             transformer_cls(
                 shell=self.shell, prefilter_manager=self, parent=self
             )
 
     def sort_transformers(self):
         """Sort the transformers by priority.
 
         This must be called after the priority of a transformer is changed.
         The :meth:`register_transformer` method calls this automatically.
         """
         self._transformers.sort(key=lambda x: x.priority)
 
     @property
     def transformers(self):
         """Return a list of checkers, sorted by priority."""
         return self._transformers
 
     def register_transformer(self, transformer):
         """Register a transformer instance."""
         if transformer not in self._transformers:
             self._transformers.append(transformer)
             self.sort_transformers()
 
     def unregister_transformer(self, transformer):
         """Unregister a transformer instance."""
         if transformer in self._transformers:
             self._transformers.remove(transformer)
 
     #-------------------------------------------------------------------------
     # API for managing checkers
     #-------------------------------------------------------------------------
 
     def init_checkers(self):
         """Create the default checkers."""
         self._checkers = []
         for checker in _default_checkers:
             checker(
                 shell=self.shell, prefilter_manager=self, parent=self
             )
 
     def sort_checkers(self):
         """Sort the checkers by priority.
 
         This must be called after the priority of a checker is changed.
         The :meth:`register_checker` method calls this automatically.
         """
         self._checkers.sort(key=lambda x: x.priority)
 
     @property
     def checkers(self):
         """Return a list of checkers, sorted by priority."""
         return self._checkers
 
     def register_checker(self, checker):
         """Register a checker instance."""
         if checker not in self._checkers:
             self._checkers.append(checker)
             self.sort_checkers()
 
     def unregister_checker(self, checker):
         """Unregister a checker instance."""
         if checker in self._checkers:
             self._checkers.remove(checker)
 
     #-------------------------------------------------------------------------
     # API for managing handlers
     #-------------------------------------------------------------------------
 
     def init_handlers(self):
         """Create the default handlers."""
         self._handlers = {}
         self._esc_handlers = {}
         for handler in _default_handlers:
             handler(
                 shell=self.shell, prefilter_manager=self, parent=self
             )
 
     @property
     def handlers(self):
         """Return a dict of all the handlers."""
         return self._handlers
 
     def register_handler(self, name, handler, esc_strings):
         """Register a handler instance by name with esc_strings."""
         self._handlers[name] = handler
         for esc_str in esc_strings:
             self._esc_handlers[esc_str] = handler
 
     def unregister_handler(self, name, handler, esc_strings):
         """Unregister a handler instance by name with esc_strings."""
         try:
             del self._handlers[name]
         except KeyError:
             pass
         for esc_str in esc_strings:
             h = self._esc_handlers.get(esc_str)
             if h is handler:
                 del self._esc_handlers[esc_str]
 
     def get_handler_by_name(self, name):
         """Get a handler by its name."""
         return self._handlers.get(name)
 
     def get_handler_by_esc(self, esc_str):
         """Get a handler by its escape string."""
         return self._esc_handlers.get(esc_str)
 
     #-------------------------------------------------------------------------
     # Main prefiltering API
     #-------------------------------------------------------------------------
 
     def prefilter_line_info(self, line_info):
         """Prefilter a line that has been converted to a LineInfo object.
 
         This implements the checker/handler part of the prefilter pipe.
         """
         # print "prefilter_line_info: ", line_info
         handler = self.find_handler(line_info)
         return handler.handle(line_info)
 
     def find_handler(self, line_info):
         """Find a handler for the line_info by trying checkers."""
         for checker in self.checkers:
             if checker.enabled:
                 handler = checker.check(line_info)
                 if handler:
                     return handler
         return self.get_handler_by_name('normal')
 
     def transform_line(self, line, continue_prompt):
         """Calls the enabled transformers in order of increasing priority."""
         for transformer in self.transformers:
             if transformer.enabled:
                 line = transformer.transform(line, continue_prompt)
         return line
 
     def prefilter_line(self, line, continue_prompt=False):
         """Prefilter a single input line as text.
 
         This method prefilters a single line of text by calling the
         transformers and then the checkers/handlers.
         """
 
         # print "prefilter_line: ", line, continue_prompt
         # All handlers *must* return a value, even if it's blank ('').
 
         # save the line away in case we crash, so the post-mortem handler can
         # record it
         self.shell._last_input_line = line
 
         if not line:
             # Return immediately on purely empty lines, so that if the user
             # previously typed some whitespace that started a continuation
             # prompt, he can break out of that loop with just an empty line.
             # This is how the default python prompt works.
             return ''
 
         # At this point, we invoke our transformers.
         if not continue_prompt or (continue_prompt and self.multi_line_specials):
             line = self.transform_line(line, continue_prompt)
 
         # Now we compute line_info for the checkers and handlers
         line_info = LineInfo(line, continue_prompt)
 
         # the input history needs to track even empty lines
         stripped = line.strip()
 
         normal_handler = self.get_handler_by_name('normal')
         if not stripped:
             return normal_handler.handle(line_info)
 
         # special handlers are only allowed for single line statements
         if continue_prompt and not self.multi_line_specials:
             return normal_handler.handle(line_info)
 
         prefiltered = self.prefilter_line_info(line_info)
         # print "prefiltered line: %r" % prefiltered
         return prefiltered
 
     def prefilter_lines(self, lines, continue_prompt=False):
         """Prefilter multiple input lines of text.
 
         This is the main entry point for prefiltering multiple lines of
         input.  This simply calls :meth:`prefilter_line` for each line of
         input.
 
         This covers cases where there are multiple lines in the user entry,
         which is the case when the user goes back to a multiline history
         entry and presses enter.
         """
         llines = lines.rstrip('\n').split('\n')
         # We can get multiple lines in one shot, where multiline input 'blends'
         # into one line, in cases like recalling from the readline history
         # buffer.  We need to make sure that in such cases, we correctly
         # communicate downstream which line is first and which are continuation
         # ones.
         if len(llines) > 1:
             out = '\n'.join([self.prefilter_line(line, lnum>0)
                              for lnum, line in enumerate(llines) ])
         else:
             out = self.prefilter_line(llines[0], continue_prompt)
 
         return out
 
 #-----------------------------------------------------------------------------
 # Prefilter transformers
 #-----------------------------------------------------------------------------
 
 
 class PrefilterTransformer(Configurable):
     """Transform a line of user input."""
 
     priority = Integer(100).tag(config=True)
     # Transformers don't currently use shell or prefilter_manager, but as we
     # move away from checkers and handlers, they will need them.
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
     prefilter_manager = Instance('IPython.core.prefilter.PrefilterManager', allow_none=True)
     enabled = Bool(True).tag(config=True)
 
     def __init__(self, shell=None, prefilter_manager=None, **kwargs):
         super(PrefilterTransformer, self).__init__(
             shell=shell, prefilter_manager=prefilter_manager, **kwargs
         )
         self.prefilter_manager.register_transformer(self)
 
     def transform(self, line, continue_prompt):
         """Transform a line, returning the new one."""
         return None
 
     def __repr__(self):
         return "<%s(priority=%r, enabled=%r)>" % (
             self.__class__.__name__, self.priority, self.enabled)
 
 
 #-----------------------------------------------------------------------------
 # Prefilter checkers
 #-----------------------------------------------------------------------------
 
 
 class PrefilterChecker(Configurable):
     """Inspect an input line and return a handler for that line."""
 
     priority = Integer(100).tag(config=True)
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
     prefilter_manager = Instance('IPython.core.prefilter.PrefilterManager', allow_none=True)
     enabled = Bool(True).tag(config=True)
 
     def __init__(self, shell=None, prefilter_manager=None, **kwargs):
         super(PrefilterChecker, self).__init__(
             shell=shell, prefilter_manager=prefilter_manager, **kwargs
         )
         self.prefilter_manager.register_checker(self)
 
     def check(self, line_info):
         """Inspect line_info and return a handler instance or None."""
         return None
 
     def __repr__(self):
         return "<%s(priority=%r, enabled=%r)>" % (
             self.__class__.__name__, self.priority, self.enabled)
 
 
 class EmacsChecker(PrefilterChecker):
 
     priority = Integer(100).tag(config=True)
     enabled = Bool(False).tag(config=True)
 
     def check(self, line_info):
         "Emacs ipython-mode tags certain input lines."
         if line_info.line.endswith('# PYTHON-MODE'):
             return self.prefilter_manager.get_handler_by_name('emacs')
         else:
             return None
 
 
 class MacroChecker(PrefilterChecker):
 
     priority = Integer(250).tag(config=True)
 
     def check(self, line_info):
         obj = self.shell.user_ns.get(line_info.ifun)
         if isinstance(obj, Macro):
             return self.prefilter_manager.get_handler_by_name('macro')
         else:
             return None
 
 
 class IPyAutocallChecker(PrefilterChecker):
 
     priority = Integer(300).tag(config=True)
 
     def check(self, line_info):
         "Instances of IPyAutocall in user_ns get autocalled immediately"
         obj = self.shell.user_ns.get(line_info.ifun, None)
         if isinstance(obj, IPyAutocall):
             obj.set_ip(self.shell)
             return self.prefilter_manager.get_handler_by_name('auto')
         else:
             return None
 
 
 class AssignmentChecker(PrefilterChecker):
 
     priority = Integer(600).tag(config=True)
 
     def check(self, line_info):
         """Check to see if user is assigning to a var for the first time, in
         which case we want to avoid any sort of automagic / autocall games.
 
         This allows users to assign to either alias or magic names true python
         variables (the magic/alias systems always take second seat to true
         python code).  E.g. ls='hi', or ls,that=1,2"""
         if line_info.the_rest:
             if line_info.the_rest[0] in '=,':
                 return self.prefilter_manager.get_handler_by_name('normal')
         else:
             return None
 
 
 class AutoMagicChecker(PrefilterChecker):
 
     priority = Integer(700).tag(config=True)
 
     def check(self, line_info):
         """If the ifun is magic, and automagic is on, run it.  Note: normal,
         non-auto magic would already have been triggered via '%' in
         check_esc_chars. This just checks for automagic.  Also, before
         triggering the magic handler, make sure that there is nothing in the
         user namespace which could shadow it."""
         if not self.shell.automagic or not self.shell.find_magic(line_info.ifun):
             return None
 
         # We have a likely magic method.  Make sure we should actually call it.
         if line_info.continue_prompt and not self.prefilter_manager.multi_line_specials:
             return None
 
         head = line_info.ifun.split('.',1)[0]
         if is_shadowed(head, self.shell):
             return None
 
         return self.prefilter_manager.get_handler_by_name('magic')
 
 
 class PythonOpsChecker(PrefilterChecker):
 
     priority = Integer(900).tag(config=True)
 
     def check(self, line_info):
         """If the 'rest' of the line begins with a function call or pretty much
         any python operator, we should simply execute the line (regardless of
         whether or not there's a possible autocall expansion).  This avoids
         spurious (and very confusing) geattr() accesses."""
         if line_info.the_rest and line_info.the_rest[0] in '!=()<>,+*/%^&|':
             return self.prefilter_manager.get_handler_by_name('normal')
         else:
             return None
 
 
 class AutocallChecker(PrefilterChecker):
 
     priority = Integer(1000).tag(config=True)
 
     function_name_regexp = CRegExp(re_fun_name,
         help="RegExp to identify potential function names."
         ).tag(config=True)
     exclude_regexp = CRegExp(re_exclude_auto,
         help="RegExp to exclude strings with this start from autocalling."
         ).tag(config=True)
 
     def check(self, line_info):
         "Check if the initial word/function is callable and autocall is on."
         if not self.shell.autocall:
             return None
 
         oinfo = line_info.ofind(self.shell) # This can mutate state via getattr
         if not oinfo['found']:
             return None
 
         if callable(oinfo['obj']) \
                and (not self.exclude_regexp.match(line_info.the_rest)) \
                and self.function_name_regexp.match(line_info.ifun):
             return self.prefilter_manager.get_handler_by_name('auto')
         else:
             return None
 
 
 #-----------------------------------------------------------------------------
 # Prefilter handlers
 #-----------------------------------------------------------------------------
 
 
 class PrefilterHandler(Configurable):
 
     handler_name = Unicode('normal')
     esc_strings = List([])
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
     prefilter_manager = Instance('IPython.core.prefilter.PrefilterManager', allow_none=True)
 
     def __init__(self, shell=None, prefilter_manager=None, **kwargs):
         super(PrefilterHandler, self).__init__(
             shell=shell, prefilter_manager=prefilter_manager, **kwargs
         )
         self.prefilter_manager.register_handler(
             self.handler_name,
             self,
             self.esc_strings
         )
 
     def handle(self, line_info):
         # print "normal: ", line_info
         """Handle normal input lines. Use as a template for handlers."""
 
         # With autoindent on, we need some way to exit the input loop, and I
         # don't want to force the user to have to backspace all the way to
         # clear the line.  The rule will be in this case, that either two
         # lines of pure whitespace in a row, or a line of pure whitespace but
         # of a size different to the indent level, will exit the input loop.
         line = line_info.line
         continue_prompt = line_info.continue_prompt
 
         if (continue_prompt and
             self.shell.autoindent and
             line.isspace() and
             0 < abs(len(line) - self.shell.indent_current_nsp) <= 2):
             line = ''
 
         return line
 
     def __str__(self):
         return "<%s(name=%s)>" % (self.__class__.__name__, self.handler_name)
 
 
 class MacroHandler(PrefilterHandler):
     handler_name = Unicode("macro")
 
     def handle(self, line_info):
         obj = self.shell.user_ns.get(line_info.ifun)
         pre_space = line_info.pre_whitespace
         line_sep = "\n" + pre_space
         return pre_space + line_sep.join(obj.value.splitlines())
 
 
 class MagicHandler(PrefilterHandler):
 
     handler_name = Unicode('magic')
     esc_strings = List([ESC_MAGIC])
 
     def handle(self, line_info):
         """Execute magic functions."""
         ifun    = line_info.ifun
         the_rest = line_info.the_rest
         cmd = '%sget_ipython().magic(%r)' % (line_info.pre_whitespace,
                                                     (ifun + " " + the_rest))
         return cmd
 
 
 class AutoHandler(PrefilterHandler):
 
     handler_name = Unicode('auto')
     esc_strings = List([ESC_PAREN, ESC_QUOTE, ESC_QUOTE2])
 
     def handle(self, line_info):
         """Handle lines which can be auto-executed, quoting if requested."""
         line    = line_info.line
         ifun    = line_info.ifun
         the_rest = line_info.the_rest
         esc     = line_info.esc
         continue_prompt = line_info.continue_prompt
         obj = line_info.ofind(self.shell)['obj']
 
         # This should only be active for single-line input!
         if continue_prompt:
             return line
 
         force_auto = isinstance(obj, IPyAutocall)
 
         # User objects sometimes raise exceptions on attribute access other
         # than AttributeError (we've seen it in the past), so it's safest to be
         # ultra-conservative here and catch all.
         try:
             auto_rewrite = obj.rewrite
         except Exception:
             auto_rewrite = True
 
         if esc == ESC_QUOTE:
             # Auto-quote splitting on whitespace
             newcmd = '%s("%s")' % (ifun,'", "'.join(the_rest.split()) )
         elif esc == ESC_QUOTE2:
             # Auto-quote whole string
             newcmd = '%s("%s")' % (ifun,the_rest)
         elif esc == ESC_PAREN:
             newcmd = '%s(%s)' % (ifun,",".join(the_rest.split()))
         else:
             # Auto-paren.       
             if force_auto:
                 # Don't rewrite if it is already a call.
                 do_rewrite = not the_rest.startswith('(')
             else:
                 if not the_rest:
                     # We only apply it to argument-less calls if the autocall
                     # parameter is set to 2.
                     do_rewrite = (self.shell.autocall >= 2)
                 elif the_rest.startswith('[') and hasattr(obj, '__getitem__'):
                     # Don't autocall in this case: item access for an object
                     # which is BOTH callable and implements __getitem__.
                     do_rewrite = False
                 else:
                     do_rewrite = True
 
             # Figure out the rewritten command
             if do_rewrite:
                 if the_rest.endswith(';'):
                     newcmd = '%s(%s);' % (ifun.rstrip(),the_rest[:-1])
                 else:
                     newcmd = '%s(%s)' % (ifun.rstrip(), the_rest)                
             else:
                 normal_handler = self.prefilter_manager.get_handler_by_name('normal')
                 return normal_handler.handle(line_info)
         
         # Display the rewritten call
         if auto_rewrite:
             self.shell.auto_rewrite_input(newcmd)
 
         return newcmd
 
 
 class EmacsHandler(PrefilterHandler):
 
     handler_name = Unicode('emacs')
     esc_strings = List([])
 
     def handle(self, line_info):
         """Handle input lines marked by python-mode."""
 
         # Currently, nothing is done.  Later more functionality can be added
         # here if needed.
 
         # The input cache shouldn't be updated
         return line_info.line
 
 
 #-----------------------------------------------------------------------------
 # Defaults
 #-----------------------------------------------------------------------------
 
 
 _default_transformers = [
 ]
 
 _default_checkers = [
     EmacsChecker,
     MacroChecker,
     IPyAutocallChecker,
     AssignmentChecker,
     AutoMagicChecker,
     PythonOpsChecker,
     AutocallChecker
 ]
 
 _default_handlers = [
     PrefilterHandler,
     MacroHandler,
     MagicHandler,
     AutoHandler,
     EmacsHandler
 ]

IPython/core/profiledir.py

@@ -1,234 +1,224 b''
 # encoding: utf-8
 """An object for managing IPython profile directories."""
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import os
 import shutil
 import errno
 
 from traitlets.config.configurable import LoggingConfigurable
 from IPython.paths import get_ipython_package_dir
 from IPython.utils.path import expand_path, ensure_dir_exists
 from IPython.utils import py3compat
-from traitlets import Unicode, Bool
+from traitlets import Unicode, Bool, observe
 
 #-----------------------------------------------------------------------------
 # Module errors
 #-----------------------------------------------------------------------------
 
 class ProfileDirError(Exception):
     pass
 
 
 #-----------------------------------------------------------------------------
 # Class for managing profile directories
 #-----------------------------------------------------------------------------
 
 class ProfileDir(LoggingConfigurable):
     """An object to manage the profile directory and its resources.
 
     The profile directory is used by all IPython applications, to manage
     configuration, logging and security.
 
     This object knows how to find, create and manage these directories. This
     should be used by any code that wants to handle profiles.
     """
 
     security_dir_name = Unicode('security')
     log_dir_name = Unicode('log')
     startup_dir_name = Unicode('startup')
     pid_dir_name = Unicode('pid')
     static_dir_name = Unicode('static')
     security_dir = Unicode(u'')
     log_dir = Unicode(u'')
     startup_dir = Unicode(u'')
     pid_dir = Unicode(u'')
     static_dir = Unicode(u'')
 
-    location = Unicode(u'', config=True,
+    location = Unicode(u'',
         help="""Set the profile location directly. This overrides the logic used by the
         `profile` option.""",
-        )
+        ).tag(config=True)
 
     _location_isset = Bool(False) # flag for detecting multiply set location
-
-    def _location_changed(self, name, old, new):
+    @observe('location')
+    def _location_changed(self, change):
         if self._location_isset:
             raise RuntimeError("Cannot set profile location more than once.")
         self._location_isset = True
+        new = change['new']
         ensure_dir_exists(new)
 
         # ensure config files exist:
         self.security_dir = os.path.join(new, self.security_dir_name)
         self.log_dir = os.path.join(new, self.log_dir_name)
         self.startup_dir = os.path.join(new, self.startup_dir_name)
         self.pid_dir = os.path.join(new, self.pid_dir_name)
         self.static_dir = os.path.join(new, self.static_dir_name)
         self.check_dirs()
-
-    def _log_dir_changed(self, name, old, new):
-        self.check_log_dir()
-
+    
     def _mkdir(self, path, mode=None):
         """ensure a directory exists at a given path
 
         This is a version of os.mkdir, with the following differences:
 
         - returns True if it created the directory, False otherwise
         - ignores EEXIST, protecting against race conditions where
           the dir may have been created in between the check and
           the creation
         - sets permissions if requested and the dir already exists
         """
         if os.path.exists(path):
             if mode and os.stat(path).st_mode != mode:
                 try:
                     os.chmod(path, mode)
                 except OSError:
                     self.log.warning(
                         "Could not set permissions on %s",
                         path
                     )
             return False
         try:
             if mode:
                 os.mkdir(path, mode)
             else:
                 os.mkdir(path)
         except OSError as e:
             if e.errno == errno.EEXIST:
                 return False
             else:
                 raise
 
         return True
-
-    def check_log_dir(self):
+    
+    @observe('log_dir')
+    def check_log_dir(self, change=None):
         self._mkdir(self.log_dir)
-
-    def _startup_dir_changed(self, name, old, new):
-        self.check_startup_dir()
-
-    def check_startup_dir(self):
+    
+    @observe('startup_dir')
+    def check_startup_dir(self, change=None):
         self._mkdir(self.startup_dir)
 
         readme = os.path.join(self.startup_dir, 'README')
         src = os.path.join(get_ipython_package_dir(), u'core', u'profile', u'README_STARTUP')
 
         if not os.path.exists(src):
             self.log.warning("Could not copy README_STARTUP to startup dir. Source file %s does not exist.", src)
 
         if os.path.exists(src) and not os.path.exists(readme):
             shutil.copy(src, readme)
 
-    def _security_dir_changed(self, name, old, new):
-        self.check_security_dir()
-
-    def check_security_dir(self):
+    @observe('security_dir')
+    def check_security_dir(self, change=None):
         self._mkdir(self.security_dir, 0o40700)
 
-    def _pid_dir_changed(self, name, old, new):
-        self.check_pid_dir()
-
-    def check_pid_dir(self):
+    @observe('pid_dir')
+    def check_pid_dir(self, change=None):
         self._mkdir(self.pid_dir, 0o40700)
 
-    def _static_dir_changed(self, name, old, new):
-        self.check_startup_dir()
-
     def check_dirs(self):
         self.check_security_dir()
         self.check_log_dir()
         self.check_pid_dir()
         self.check_startup_dir()
 
     def copy_config_file(self, config_file, path=None, overwrite=False):
         """Copy a default config file into the active profile directory.
 
         Default configuration files are kept in :mod:`IPython.core.profile`.
         This function moves these from that location to the working profile
         directory.
         """
         dst = os.path.join(self.location, config_file)
         if os.path.isfile(dst) and not overwrite:
             return False
         if path is None:
             path = os.path.join(get_ipython_package_dir(), u'core', u'profile', u'default')
         src = os.path.join(path, config_file)
         shutil.copy(src, dst)
         return True
 
     @classmethod
     def create_profile_dir(cls, profile_dir, config=None):
         """Create a new profile directory given a full path.
 
         Parameters
         ----------
         profile_dir : str
             The full path to the profile directory.  If it does exist, it will
             be used.  If not, it will be created.
         """
         return cls(location=profile_dir, config=config)
 
     @classmethod
     def create_profile_dir_by_name(cls, path, name=u'default', config=None):
         """Create a profile dir by profile name and path.
 
         Parameters
         ----------
         path : unicode
             The path (directory) to put the profile directory in.
         name : unicode
             The name of the profile.  The name of the profile directory will
             be "profile_<profile>".
         """
         if not os.path.isdir(path):
             raise ProfileDirError('Directory not found: %s' % path)
         profile_dir = os.path.join(path, u'profile_' + name)
         return cls(location=profile_dir, config=config)
 
     @classmethod
     def find_profile_dir_by_name(cls, ipython_dir, name=u'default', config=None):
         """Find an existing profile dir by profile name, return its ProfileDir.
 
         This searches through a sequence of paths for a profile dir.  If it
         is not found, a :class:`ProfileDirError` exception will be raised.
 
         The search path algorithm is:
         1. ``py3compat.getcwd()``
         2. ``ipython_dir``
 
         Parameters
         ----------
         ipython_dir : unicode or str
             The IPython directory to use.
         name : unicode or str
             The name of the profile.  The name of the profile directory
             will be "profile_<profile>".
         """
         dirname = u'profile_' + name
         paths = [py3compat.getcwd(), ipython_dir]
         for p in paths:
             profile_dir = os.path.join(p, dirname)
             if os.path.isdir(profile_dir):
                 return cls(location=profile_dir, config=config)
         else:
             raise ProfileDirError('Profile directory not found in paths: %s' % dirname)
 
     @classmethod
     def find_profile_dir(cls, profile_dir, config=None):
         """Find/create a profile dir and return its ProfileDir.
 
         This will create the profile directory if it doesn't exist.
 
         Parameters
         ----------
         profile_dir : unicode or str
             The path of the profile directory.
         """
         profile_dir = expand_path(profile_dir)
         if not os.path.isdir(profile_dir):
             raise ProfileDirError('Profile directory not found: %s' % profile_dir)
         return cls(location=profile_dir, config=config)

IPython/core/prompts.py

@@ -1,420 +1,409 b''
 # -*- coding: utf-8 -*-
-"""Classes for handling input/output prompts.
+"""Classes for handling input/output prompts."""
 
-Authors:
-
-* Fernando Perez
-* Brian Granger
-* Thomas Kluyver
-"""
-
-#-----------------------------------------------------------------------------
-#       Copyright (C) 2008-2011 The IPython Development Team
-#       Copyright (C) 2001-2007 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.
-#-----------------------------------------------------------------------------
-
-#-----------------------------------------------------------------------------
-# Imports
-#-----------------------------------------------------------------------------
+# Copyright (c) 2001-2007 Fernando Perez <[e-mail]>
+# Copyright (c) IPython Development Team.
+# Distributed under the terms of the Modified BSD License.
 
 import os
 import re
 import socket
 import sys
 import time
 
 from string import Formatter
 
 from traitlets.config.configurable import Configurable
 from IPython.core import release
 from IPython.utils import coloransi, py3compat
-from traitlets import Unicode, Instance, Dict, Bool, Int, observe
+from traitlets import Unicode, Instance, Dict, Bool, Int, observe, default
 
 from IPython.utils.PyColorize import LightBGColors, LinuxColors, NoColor
 
 #-----------------------------------------------------------------------------
 # Color schemes for prompts
 #-----------------------------------------------------------------------------
 
 InputColors = coloransi.InputTermColors  # just a shorthand
 Colors = coloransi.TermColors  # just a shorthand
 
 color_lists = dict(normal=Colors(), inp=InputColors(), nocolor=coloransi.NoColors())
 
 #-----------------------------------------------------------------------------
 # Utilities
 #-----------------------------------------------------------------------------
 
 class LazyEvaluate(object):
     """This is used for formatting strings with values that need to be updated
     at that time, such as the current time or working directory."""
     def __init__(self, func, *args, **kwargs):
         self.func = func
         self.args = args
         self.kwargs = kwargs
 
     def __call__(self, **kwargs):
         self.kwargs.update(kwargs)
         return self.func(*self.args, **self.kwargs)
 
     def __str__(self):
         return str(self())
 
     def __unicode__(self):
         return py3compat.unicode_type(self())
 
     def __format__(self, format_spec):
         return format(self(), format_spec)
 
 def multiple_replace(dict, text):
     """ Replace in 'text' all occurrences of any key in the given
     dictionary by its corresponding value.  Returns the new string."""
 
     # Function by Xavier Defrang, originally found at:
     # http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/81330
 
     # Create a regular expression  from the dictionary keys
     regex = re.compile("(%s)" % "|".join(map(re.escape, dict.keys())))
     # For each match, look-up corresponding value in dictionary
     return regex.sub(lambda mo: dict[mo.string[mo.start():mo.end()]], text)
 
 #-----------------------------------------------------------------------------
 # Special characters that can be used in prompt templates, mainly bash-like
 #-----------------------------------------------------------------------------
 
 # If $HOME isn't defined (Windows), make it an absurd string so that it can
 # never be expanded out into '~'.  Basically anything which can never be a
 # reasonable directory name will do, we just want the $HOME -> '~' operation
 # to become a no-op.  We pre-compute $HOME here so it's not done on every
 # prompt call.
 
 # FIXME:
 
 # - This should be turned into a class which does proper namespace management,
 # since the prompt specials need to be evaluated in a certain namespace.
 # Currently it's just globals, which need to be managed manually by code
 # below.
 
 # - I also need to split up the color schemes from the prompt specials
 # somehow.  I don't have a clean design for that quite yet.
 
 HOME = py3compat.str_to_unicode(os.environ.get("HOME","//////:::::ZZZZZ,,,~~~"))
 
 # This is needed on FreeBSD, and maybe other systems which symlink /home to
 # /usr/home, but retain the $HOME variable as pointing to /home
 HOME = os.path.realpath(HOME)
 
 # We precompute a few more strings here for the prompt_specials, which are
 # fixed once ipython starts.  This reduces the runtime overhead of computing
 # prompt strings.
 USER           = py3compat.str_to_unicode(os.environ.get("USER",''))
 HOSTNAME       = py3compat.str_to_unicode(socket.gethostname())
 HOSTNAME_SHORT = HOSTNAME.split(".")[0]
 
 # IronPython doesn't currently have os.getuid() even if
 # os.name == 'posix'; 2/8/2014
 ROOT_SYMBOL    = "#" if (os.name=='nt' or sys.platform=='cli' or os.getuid()==0) else "$"
 
 prompt_abbreviations = {
     # Prompt/history count
     '%n' : '{color.number}' '{count}' '{color.prompt}',
     r'\#': '{color.number}' '{count}' '{color.prompt}',
     # Just the prompt counter number, WITHOUT any coloring wrappers, so users
     # can get numbers displayed in whatever color they want.
     r'\N': '{count}',
 
     # Prompt/history count, with the actual digits replaced by dots or
     # spaces.  Used mainly in continuation prompts (prompt_in2).
     r'\D': '{dots}',
     r'\S': '{spaces}',
 
     # Current time
     r'\T' : '{time}',
     # Current working directory
     r'\w': '{cwd}',
     # Basename of current working directory.
     # (use os.sep to make this portable across OSes)
     r'\W' : '{cwd_last}',
     # These X<N> are an extension to the normal bash prompts.  They return
     # N terms of the path, after replacing $HOME with '~'
     r'\X0': '{cwd_x[0]}',
     r'\X1': '{cwd_x[1]}',
     r'\X2': '{cwd_x[2]}',
     r'\X3': '{cwd_x[3]}',
     r'\X4': '{cwd_x[4]}',
     r'\X5': '{cwd_x[5]}',
     # Y<N> are similar to X<N>, but they show '~' if it's the directory
     # N+1 in the list.  Somewhat like %cN in tcsh.
     r'\Y0': '{cwd_y[0]}',
     r'\Y1': '{cwd_y[1]}',
     r'\Y2': '{cwd_y[2]}',
     r'\Y3': '{cwd_y[3]}',
     r'\Y4': '{cwd_y[4]}',
     r'\Y5': '{cwd_y[5]}',
     # Hostname up to first .
     r'\h': HOSTNAME_SHORT,
     # Full hostname
     r'\H': HOSTNAME,
     # Username of current user
     r'\u': USER,
     # Escaped '\'
     '\\\\': '\\',
     # Newline
     r'\n': '\n',
     # Carriage return
     r'\r': '\r',
     # Release version
     r'\v': release.version,
     # Root symbol ($ or #)
     r'\$': ROOT_SYMBOL,
     }
 
 #-----------------------------------------------------------------------------
 # More utilities
 #-----------------------------------------------------------------------------
 
 def cwd_filt(depth):
     """Return the last depth elements of the current working directory.
 
     $HOME is always replaced with '~'.
     If depth==0, the full path is returned."""
 
     cwd = py3compat.getcwd().replace(HOME,"~")
     out = os.sep.join(cwd.split(os.sep)[-depth:])
     return out or os.sep
 
 def cwd_filt2(depth):
     """Return the last depth elements of the current working directory.
 
     $HOME is always replaced with '~'.
     If depth==0, the full path is returned."""
 
     full_cwd = py3compat.getcwd()
     cwd = full_cwd.replace(HOME,"~").split(os.sep)
     if '~' in cwd and len(cwd) == depth+1:
         depth += 1
     drivepart = ''
     if sys.platform == 'win32' and len(cwd) > depth:
         drivepart = os.path.splitdrive(full_cwd)[0]
     out = drivepart + '/'.join(cwd[-depth:])
 
     return out or os.sep
 
 #-----------------------------------------------------------------------------
 # Prompt classes
 #-----------------------------------------------------------------------------
 
 lazily_evaluate = {'time': LazyEvaluate(time.strftime, "%H:%M:%S"),
                    'cwd': LazyEvaluate(py3compat.getcwd),
                    'cwd_last': LazyEvaluate(lambda: py3compat.getcwd().split(os.sep)[-1]),
                    'cwd_x': [LazyEvaluate(lambda: py3compat.getcwd().replace(HOME,"~"))] +\
                             [LazyEvaluate(cwd_filt, x) for x in range(1,6)],
                    'cwd_y': [LazyEvaluate(cwd_filt2, x) for x in range(6)]
                    }
 
 def _lenlastline(s):
     """Get the length of the last line. More intelligent than
     len(s.splitlines()[-1]).
     """
     if not s or s.endswith(('\n', '\r')):
         return 0
     return len(s.splitlines()[-1])
 
 
 invisible_chars_re = re.compile('\001[^\001\002]*\002')
 def _invisible_characters(s):
     """
     Get the number of invisible ANSI characters in s. Invisible characters
     must be delimited by \001 and \002.
     """
     return _lenlastline(s) - _lenlastline(invisible_chars_re.sub('', s))
 
 class UserNSFormatter(Formatter):
     """A Formatter that falls back on a shell's user_ns and __builtins__ for name resolution"""
     def __init__(self, shell):
         self.shell = shell
 
     def get_value(self, key, args, kwargs):
         # try regular formatting first:
         try:
             return Formatter.get_value(self, key, args, kwargs)
         except Exception:
             pass
         # next, look in user_ns and builtins:
         for container in (self.shell.user_ns, __builtins__):
             if key in container:
                 return container[key]
         # nothing found, put error message in its place
         return "<ERROR: '%s' not found>" % key
 
 
 class PromptManager(Configurable):
     """This is the primary interface for producing IPython's prompts."""
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
 
     color_scheme_table = Instance(coloransi.ColorSchemeTable, allow_none=True)
     color_scheme = Unicode('Linux').tag(config=True)
 
     @observe('color_scheme')
     def _color_scheme_changed(self, change):
         self.color_scheme_table.set_active_scheme(change['new'])
         for pname in ['in', 'in2', 'out', 'rewrite']:
             # We need to recalculate the number of invisible characters
             self.update_prompt(pname)
 
     lazy_evaluate_fields = Dict(help="""
         This maps field names used in the prompt templates to functions which
         will be called when the prompt is rendered. This allows us to include
         things like the current time in the prompts. Functions are only called
         if they are used in the prompt.
         """)
-    def _lazy_evaluate_fields_default(self): return lazily_evaluate.copy()
 
     in_template = Unicode('In [\\#]: ',
         help="Input prompt.  '\\#' will be transformed to the prompt number"
         ).tag(config=True)
     in2_template = Unicode('   .\\D.: ',
         help="Continuation prompt.").tag(config=True)
     out_template = Unicode('Out[\\#]: ',
         help="Output prompt. '\\#' will be transformed to the prompt number"
         ).tag(config=True)
 
+    @default('lazy_evaluate_fields')
+    def _lazy_evaluate_fields_default(self):
+        return lazily_evaluate.copy()
+
     justify = Bool(True, help="""
         If True (default), each prompt will be right-aligned with the
         preceding one.
         """).tag(config=True)
 
     # We actually store the expanded templates here:
     templates = Dict()
 
     # The number of characters in the last prompt rendered, not including
     # colour characters.
     width = Int()
     txtwidth = Int()   # Not including right-justification
 
     # The number of characters in each prompt which don't contribute to width
     invisible_chars = Dict()
+    @default('invisible_chars')
     def _invisible_chars_default(self):
         return {'in': 0, 'in2': 0, 'out': 0, 'rewrite':0}
 
     def __init__(self, shell, **kwargs):
         super(PromptManager, self).__init__(shell=shell, **kwargs)
 
         # Prepare colour scheme table
         self.color_scheme_table = coloransi.ColorSchemeTable([NoColor,
                                     LinuxColors, LightBGColors], self.color_scheme)
 
         self._formatter = UserNSFormatter(shell)
         # Prepare templates & numbers of invisible characters
         self.update_prompt('in', self.in_template)
         self.update_prompt('in2', self.in2_template)
         self.update_prompt('out', self.out_template)
         self.update_prompt('rewrite')
-        self.on_trait_change(self._update_prompt_trait, ['in_template',
-                            'in2_template', 'out_template'])
+        self.observe(self._update_prompt_trait,
+            names=['in_template', 'in2_template', 'out_template'])
 
     def update_prompt(self, name, new_template=None):
         """This is called when a prompt template is updated. It processes
         abbreviations used in the prompt template (like \#) and calculates how
         many invisible characters (ANSI colour escapes) the resulting prompt
         contains.
 
         It is also called for each prompt on changing the colour scheme. In both
         cases, traitlets should take care of calling this automatically.
         """
         if new_template is not None:
             self.templates[name] = multiple_replace(prompt_abbreviations, new_template)
         # We count invisible characters (colour escapes) on the last line of the
         # prompt, to calculate the width for lining up subsequent prompts.
         invis_chars = _invisible_characters(self._render(name, color=True))
         self.invisible_chars[name] = invis_chars
 
     def _update_prompt_trait(self, traitname, new_template):
         name = traitname[:-9]   # Cut off '_template'
         self.update_prompt(name, new_template)
 
     def _render(self, name, color=True, **kwargs):
         """Render but don't justify, or update the width or txtwidth attributes.
         """
         if name == 'rewrite':
             return self._render_rewrite(color=color)
 
         if color:
             scheme = self.color_scheme_table.active_colors
             if name=='out':
                 colors = color_lists['normal']
                 colors.number, colors.prompt, colors.normal = \
                         scheme.out_number, scheme.out_prompt, scheme.normal
             else:
                 colors = color_lists['inp']
                 colors.number, colors.prompt, colors.normal = \
                         scheme.in_number, scheme.in_prompt, scheme.in_normal
                 if name=='in2':
                     colors.prompt = scheme.in_prompt2
         else:
             # No color
             colors = color_lists['nocolor']
             colors.number, colors.prompt, colors.normal = '', '', ''
 
         count = self.shell.execution_count    # Shorthand
         # Build the dictionary to be passed to string formatting
         fmtargs = dict(color=colors, count=count,
                        dots="."*len(str(count)), spaces=" "*len(str(count)),
                        width=self.width, txtwidth=self.txtwidth)
         fmtargs.update(self.lazy_evaluate_fields)
         fmtargs.update(kwargs)
 
         # Prepare the prompt
         prompt = colors.prompt + self.templates[name] + colors.normal
 
         # Fill in required fields
         return self._formatter.format(prompt, **fmtargs)
 
     def _render_rewrite(self, color=True):
         """Render the ---> rewrite prompt."""
         if color:
             scheme = self.color_scheme_table.active_colors
             # We need a non-input version of these escapes
             color_prompt = scheme.in_prompt.replace("\001","").replace("\002","")
             color_normal = scheme.normal
         else:
             color_prompt, color_normal = '', ''
 
         return color_prompt + "-> ".rjust(self.txtwidth, "-") + color_normal
 
     def render(self, name, color=True, just=None, **kwargs):
         """
         Render the selected prompt.
 
         Parameters
         ----------
         name : str
           Which prompt to render. One of 'in', 'in2', 'out', 'rewrite'
         color : bool
           If True (default), include ANSI escape sequences for a coloured prompt.
         just : bool
           If True, justify the prompt to the width of the last prompt. The
           default is stored in self.justify.
         **kwargs :
           Additional arguments will be passed to the string formatting operation,
           so they can override the values that would otherwise fill in the
           template.
 
         Returns
         -------
         A string containing the rendered prompt.
         """
         res = self._render(name, color=color, **kwargs)
 
         # Handle justification of prompt
         invis_chars = self.invisible_chars[name] if color else 0
         self.txtwidth = _lenlastline(res) - invis_chars
         just = self.justify if (just is None) else just
         # If the prompt spans more than one line, don't try to justify it:
         if just and name != 'in' and ('\n' not in res) and ('\r' not in res):
             res = res.rjust(self.width + invis_chars)
         self.width = _lenlastline(res) - invis_chars
         return res

IPython/core/shellapp.py

@@ -1,440 +1,437 b''
 # encoding: utf-8
 """
 A mixin for :class:`~IPython.core.application.Application` classes that
 launch InteractiveShell instances, load extensions, etc.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 from __future__ import absolute_import
 from __future__ import print_function
 
 import glob
 import os
 import sys
 
 from traitlets.config.application import boolean_flag
 from traitlets.config.configurable import Configurable
 from traitlets.config.loader import Config
 from IPython.core import pylabtools
 from IPython.utils import py3compat
 from IPython.utils.contexts import preserve_keys
 from IPython.utils.path import filefind
 from traitlets import (
-    Unicode, Instance, List, Bool, CaselessStrEnum
+    Unicode, Instance, List, Bool, CaselessStrEnum, default, observe,
 )
 from IPython.lib.inputhook import guis
 
 #-----------------------------------------------------------------------------
 # Aliases and Flags
 #-----------------------------------------------------------------------------
 
 gui_keys = tuple(sorted([ key for key in guis if key is not None ]))
 
 backend_keys = sorted(pylabtools.backends.keys())
 backend_keys.insert(0, 'auto')
 
 shell_flags = {}
 
 addflag = lambda *args: shell_flags.update(boolean_flag(*args))
 addflag('autoindent', 'InteractiveShell.autoindent',
         'Turn on autoindenting.', 'Turn off autoindenting.'
 )
 addflag('automagic', 'InteractiveShell.automagic',
         """Turn on the auto calling of magic commands. Type %%magic at the
         IPython  prompt  for  more information.""",
         'Turn off the auto calling of magic commands.'
 )
 addflag('pdb', 'InteractiveShell.pdb',
     "Enable auto calling the pdb debugger after every exception.",
     "Disable auto calling the pdb debugger after every exception."
 )
 # pydb flag doesn't do any config, as core.debugger switches on import,
 # which is before parsing.  This just allows the flag to be passed.
 shell_flags.update(dict(
     pydb = ({},
         """Use the third party 'pydb' package as debugger, instead of pdb.
         Requires that pydb is installed."""
     )
 ))
 addflag('pprint', 'PlainTextFormatter.pprint',
     "Enable auto pretty printing of results.",
     "Disable auto pretty printing of results."
 )
 addflag('color-info', 'InteractiveShell.color_info',
     """IPython can display information about objects via a set of functions,
     and optionally can use colors for this, syntax highlighting
     source code and various other elements. This is on by default, but can cause
     problems with some pagers. If you see such problems, you can disable the
     colours.""",
     "Disable using colors for info related things."
 )
 addflag('deep-reload', 'InteractiveShell.deep_reload',
     """ **Deprecated** and will be removed in IPython 5.0.
     
     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(). This feature is off
     by default [which means that you have both normal reload() and
     dreload()].""",
     "Disable deep (recursive) reloading by default."
 )
 nosep_config = Config()
 nosep_config.InteractiveShell.separate_in = ''
 nosep_config.InteractiveShell.separate_out = ''
 nosep_config.InteractiveShell.separate_out2 = ''
 
 shell_flags['nosep']=(nosep_config, "Eliminate all spacing between prompts.")
 shell_flags['pylab'] = (
     {'InteractiveShellApp' : {'pylab' : 'auto'}},
     """Pre-load matplotlib and numpy for interactive use with
     the default matplotlib backend."""
 )
 shell_flags['matplotlib'] = (
     {'InteractiveShellApp' : {'matplotlib' : 'auto'}},
     """Configure matplotlib for interactive use with
     the default matplotlib backend."""
 )
 
 # it's possible we don't want short aliases for *all* of these:
 shell_aliases = dict(
     autocall='InteractiveShell.autocall',
     colors='InteractiveShell.colors',
     logfile='InteractiveShell.logfile',
     logappend='InteractiveShell.logappend',
     c='InteractiveShellApp.code_to_run',
     m='InteractiveShellApp.module_to_run',
     ext='InteractiveShellApp.extra_extension',
     gui='InteractiveShellApp.gui',
     pylab='InteractiveShellApp.pylab',
     matplotlib='InteractiveShellApp.matplotlib',
 )
 shell_aliases['cache-size'] = 'InteractiveShell.cache_size'
 
 #-----------------------------------------------------------------------------
 # Main classes and functions
 #-----------------------------------------------------------------------------
 
 class InteractiveShellApp(Configurable):
     """A Mixin for applications that start InteractiveShell instances.
     
     Provides configurables for loading extensions and executing files
     as part of configuring a Shell environment.
 
     The following methods should be called by the :meth:`initialize` method
     of the subclass:
 
       - :meth:`init_path`
       - :meth:`init_shell` (to be implemented by the subclass)
       - :meth:`init_gui_pylab`
       - :meth:`init_extensions`
       - :meth:`init_code`
     """
-    extensions = List(Unicode(), config=True,
+    extensions = List(Unicode(),
         help="A list of dotted module names of IPython extensions to load."
-    )
-    extra_extension = Unicode('', config=True,
+    ).tag(config=True)
+    extra_extension = Unicode('',
         help="dotted module name of an IPython extension to load."
-    )
+    ).tag(config=True)
 
-    reraise_ipython_extension_failures = Bool(
-        False,
-        config=True,
+    reraise_ipython_extension_failures = Bool(False,
         help="Reraise exceptions encountered loading IPython extensions?",
-    )
+    ).tag(config=True)
 
     # Extensions that are always loaded (not configurable)
-    default_extensions = List(Unicode(), [u'storemagic'], config=False)
+    default_extensions = List(Unicode(), [u'storemagic']).tag(config=False)
     
-    hide_initial_ns = Bool(True, config=True,
+    hide_initial_ns = Bool(True,
         help="""Should variables loaded at startup (by startup files, exec_lines, etc.)
         be hidden from tools like %who?"""
-    )
+    ).tag(config=True)
 
-    exec_files = List(Unicode(), config=True,
+    exec_files = List(Unicode(),
         help="""List of files to run at IPython startup."""
-    )
-    exec_PYTHONSTARTUP = Bool(True, config=True,
+    ).tag(config=True)
+    exec_PYTHONSTARTUP = Bool(True,
         help="""Run the file referenced by the PYTHONSTARTUP environment
         variable at IPython startup."""
-    )
-    file_to_run = Unicode('', config=True,
-        help="""A file to be run""")
+    ).tag(config=True)
+    file_to_run = Unicode('',
+        help="""A file to be run""").tag(config=True)
 
-    exec_lines = List(Unicode(), config=True,
+    exec_lines = List(Unicode(),
         help="""lines of code to run at IPython startup."""
-    )
-    code_to_run = Unicode('', config=True,
+    ).tag(config=True)
+    code_to_run = Unicode('',
         help="Execute the given command string."
-    )
-    module_to_run = Unicode('', config=True,
+    ).tag(config=True)
+    module_to_run = Unicode('',
         help="Run the module as a script."
-    )
-    gui = CaselessStrEnum(gui_keys, config=True, allow_none=True,
+    ).tag(config=True)
+    gui = CaselessStrEnum(gui_keys, allow_none=True,
         help="Enable GUI event loop integration with any of {0}.".format(gui_keys)
-    )
+    ).tag(config=True)
     matplotlib = CaselessStrEnum(backend_keys, allow_none=True,
-        config=True,
         help="""Configure matplotlib for interactive use with
         the default matplotlib backend."""
-    )
+    ).tag(config=True)
     pylab = CaselessStrEnum(backend_keys, allow_none=True,
-        config=True,
         help="""Pre-load matplotlib and numpy for interactive use,
         selecting a particular matplotlib backend and loop integration.
         """
-    )
-    pylab_import_all = Bool(True, config=True,
+    ).tag(config=True)
+    pylab_import_all = Bool(True,
         help="""If true, IPython will populate the user namespace with numpy, pylab, etc.
         and an ``import *`` is done from numpy and pylab, when using pylab mode.
         
         When False, pylab mode should not import any names into the user namespace.
         """
-    )
+    ).tag(config=True)
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC',
                      allow_none=True)
     # whether interact-loop should start
     interact = Bool(True)
     
     user_ns = Instance(dict, args=None, allow_none=True)
-    def _user_ns_changed(self, name, old, new):
+    @observe('user_ns')
+    def _user_ns_changed(self, change):
         if self.shell is not None:
-            self.shell.user_ns = new
+            self.shell.user_ns = change['new']
             self.shell.init_user_ns()
 
     def init_path(self):
         """Add current working directory, '', to sys.path"""
         if sys.path[0] != '':
             sys.path.insert(0, '')
 
     def init_shell(self):
         raise NotImplementedError("Override in subclasses")
 
     def init_gui_pylab(self):
         """Enable GUI event loop integration, taking pylab into account."""
         enable = False
         shell = self.shell
         if self.pylab:
             enable = lambda key: shell.enable_pylab(key, import_all=self.pylab_import_all)
             key = self.pylab
         elif self.matplotlib:
             enable = shell.enable_matplotlib
             key = self.matplotlib
         elif self.gui:
             enable = shell.enable_gui
             key = self.gui
         
         if not enable:
             return
         
         try:
             r = enable(key)
         except ImportError:
             self.log.warning("Eventloop or matplotlib integration failed. Is matplotlib installed?")
             self.shell.showtraceback()
             return
         except Exception:
             self.log.warning("GUI event loop or pylab initialization failed")
             self.shell.showtraceback()
             return
             
         if isinstance(r, tuple):
             gui, backend = r[:2]
             self.log.info("Enabling GUI event loop integration, "
                       "eventloop=%s, matplotlib=%s", gui, backend)
             if key == "auto":
                 print("Using matplotlib backend: %s" % backend)
         else:
             gui = r
             self.log.info("Enabling GUI event loop integration, "
                       "eventloop=%s", gui)
 
     def init_extensions(self):
         """Load all IPython extensions in IPythonApp.extensions.
 
         This uses the :meth:`ExtensionManager.load_extensions` to load all
         the extensions listed in ``self.extensions``.
         """
         try:
             self.log.debug("Loading IPython extensions...")
             extensions = self.default_extensions + self.extensions
             if self.extra_extension:
                 extensions.append(self.extra_extension)
             for ext in extensions:
                 try:
                     self.log.info("Loading IPython extension: %s" % ext)
                     self.shell.extension_manager.load_extension(ext)
                 except:
                     if self.reraise_ipython_extension_failures:
                         raise
                     msg = ("Error in loading extension: {ext}\n"
                            "Check your config files in {location}".format(
                                ext=ext,
                                location=self.profile_dir.location
                            ))
                     self.log.warning(msg, exc_info=True)
         except:
             if self.reraise_ipython_extension_failures:
                 raise
             self.log.warning("Unknown error in loading extensions:", exc_info=True)
 
     def init_code(self):
         """run the pre-flight code, specified via exec_lines"""
         self._run_startup_files()
         self._run_exec_lines()
         self._run_exec_files()
         
         # Hide variables defined here from %who etc.
         if self.hide_initial_ns:
             self.shell.user_ns_hidden.update(self.shell.user_ns)
         
         # command-line execution (ipython -i script.py, ipython -m module)
         # should *not* be excluded from %whos
         self._run_cmd_line_code()
         self._run_module()
         
         # flush output, so itwon't be attached to the first cell
         sys.stdout.flush()
         sys.stderr.flush()
 
     def _run_exec_lines(self):
         """Run lines of code in IPythonApp.exec_lines in the user's namespace."""
         if not self.exec_lines:
             return
         try:
             self.log.debug("Running code from IPythonApp.exec_lines...")
             for line in self.exec_lines:
                 try:
                     self.log.info("Running code in user namespace: %s" %
                                   line)
                     self.shell.run_cell(line, store_history=False)
                 except:
                     self.log.warning("Error in executing line in user "
                                   "namespace: %s" % line)
                     self.shell.showtraceback()
         except:
             self.log.warning("Unknown error in handling IPythonApp.exec_lines:")
             self.shell.showtraceback()
 
     def _exec_file(self, fname, shell_futures=False):
         try:
             full_filename = filefind(fname, [u'.', self.ipython_dir])
         except IOError as e:
             self.log.warning("File not found: %r"%fname)
             return
         # Make sure that the running script gets a proper sys.argv as if it
         # were run from a system shell.
         save_argv = sys.argv
         sys.argv = [full_filename] + self.extra_args[1:]
         # protect sys.argv from potential unicode strings on Python 2:
         if not py3compat.PY3:
             sys.argv = [ py3compat.cast_bytes(a) for a in sys.argv ]
         try:
             if os.path.isfile(full_filename):
                 self.log.info("Running file in user namespace: %s" %
                               full_filename)
                 # Ensure that __file__ is always defined to match Python
                 # behavior.
                 with preserve_keys(self.shell.user_ns, '__file__'):
                     self.shell.user_ns['__file__'] = fname
                     if full_filename.endswith('.ipy'):
                         self.shell.safe_execfile_ipy(full_filename,
                                                      shell_futures=shell_futures)
                     else:
                         # default to python, even without extension
                         self.shell.safe_execfile(full_filename,
                                                  self.shell.user_ns,
                                                  shell_futures=shell_futures,
                                                  raise_exceptions=True)
         finally:
             sys.argv = save_argv
 
     def _run_startup_files(self):
         """Run files from profile startup directory"""
         startup_dir = self.profile_dir.startup_dir
         startup_files = []
         
         if self.exec_PYTHONSTARTUP and os.environ.get('PYTHONSTARTUP', False) and \
                 not (self.file_to_run or self.code_to_run or self.module_to_run):
             python_startup = os.environ['PYTHONSTARTUP']
             self.log.debug("Running PYTHONSTARTUP file %s...", python_startup)
             try:
                 self._exec_file(python_startup)
             except:
                 self.log.warning("Unknown error in handling PYTHONSTARTUP file %s:", python_startup)
                 self.shell.showtraceback()
             finally:
                 # Many PYTHONSTARTUP files set up the readline completions,
                 # but this is often at odds with IPython's own completions.
                 # Do not allow PYTHONSTARTUP to set up readline.
                 if self.shell.has_readline:
                     self.shell.set_readline_completer()
         
         startup_files += glob.glob(os.path.join(startup_dir, '*.py'))
         startup_files += glob.glob(os.path.join(startup_dir, '*.ipy'))
         if not startup_files:
             return
         
         self.log.debug("Running startup files from %s...", startup_dir)
         try:
             for fname in sorted(startup_files):
                 self._exec_file(fname)
         except:
             self.log.warning("Unknown error in handling startup files:")
             self.shell.showtraceback()
 
     def _run_exec_files(self):
         """Run files from IPythonApp.exec_files"""
         if not self.exec_files:
             return
 
         self.log.debug("Running files in IPythonApp.exec_files...")
         try:
             for fname in self.exec_files:
                 self._exec_file(fname)
         except:
             self.log.warning("Unknown error in handling IPythonApp.exec_files:")
             self.shell.showtraceback()
 
     def _run_cmd_line_code(self):
         """Run code or file specified at the command-line"""
         if self.code_to_run:
             line = self.code_to_run
             try:
                 self.log.info("Running code given at command line (c=): %s" %
                               line)
                 self.shell.run_cell(line, store_history=False)
             except:
                 self.log.warning("Error in executing line in user namespace: %s" %
                               line)
                 self.shell.showtraceback()
                 if not self.interact:
                     self.exit(1)
 
         # Like Python itself, ignore the second if the first of these is present
         elif self.file_to_run:
             fname = self.file_to_run
             try:
                 self._exec_file(fname, shell_futures=True)
             except:
                 self.shell.showtraceback(tb_offset=4)
                 if not self.interact:
                     self.exit(1)
 
     def _run_module(self):
         """Run module specified at the command-line."""
         if self.module_to_run:
             # Make sure that the module gets a proper sys.argv as if it were
             # run using `python -m`.
             save_argv = sys.argv
             sys.argv = [sys.executable] + self.extra_args
             try:
                 self.shell.safe_run_module(self.module_to_run,
                                            self.shell.user_ns)
             finally:
                 sys.argv = save_argv

IPython/extensions/storemagic.py

@@ -1,241 +1,228 b''
 # -*- coding: utf-8 -*-
 """
 %store magic for lightweight persistence.
 
 Stores variables, aliases and macros in IPython's database.
 
 To automatically restore stored variables at startup, add this to your
 :file:`ipython_config.py` file::
 
   c.StoreMagics.autorestore = True
 """
 from __future__ import print_function
-#-----------------------------------------------------------------------------
-#  Copyright (c) 2012, The 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
-#-----------------------------------------------------------------------------
-
-# Stdlib
+
+# Copyright (c) IPython Development Team.
+# Distributed under the terms of the Modified BSD License.
+
 import inspect, os, sys, textwrap
 
-# Our own
 from IPython.core.error import UsageError
 from IPython.core.magic import Magics, magics_class, line_magic
 from traitlets import Bool
 from IPython.utils.py3compat import string_types
 
-#-----------------------------------------------------------------------------
-# Functions and classes
-#-----------------------------------------------------------------------------
 
 def restore_aliases(ip):
     staliases = ip.db.get('stored_aliases', {})
     for k,v in staliases.items():
         #print "restore alias",k,v # dbg
         #self.alias_table[k] = v
         ip.alias_manager.define_alias(k,v)
 
 
 def refresh_variables(ip):
     db = ip.db
     for key in db.keys('autorestore/*'):
         # strip autorestore
         justkey = os.path.basename(key)
         try:
             obj = db[key]
         except KeyError:
             print("Unable to restore variable '%s', ignoring (use %%store -d to forget!)" % justkey)
             print("The error was:", sys.exc_info()[0])
         else:
             #print "restored",justkey,"=",obj #dbg
             ip.user_ns[justkey] = obj
 
 
 def restore_dhist(ip):
     ip.user_ns['_dh'] = ip.db.get('dhist',[])
 
 
 def restore_data(ip):
     refresh_variables(ip)
     restore_aliases(ip)
     restore_dhist(ip)
 
 
 @magics_class
 class StoreMagics(Magics):
     """Lightweight persistence for python variables.
 
     Provides the %store magic."""
     
-    autorestore = Bool(False, config=True, help=
+    autorestore = Bool(False, help=
         """If True, any %store-d variables will be automatically restored
         when IPython starts.
         """
-    )
+    ).tag(config=True)
     
     def __init__(self, shell):
         super(StoreMagics, self).__init__(shell=shell)
         self.shell.configurables.append(self)
         if self.autorestore:
             restore_data(self.shell)
 
     @line_magic
     def store(self, parameter_s=''):
         """Lightweight persistence for python variables.
 
         Example::
 
           In [1]: l = ['hello',10,'world']
           In [2]: %store l
           In [3]: exit
 
           (IPython session is closed and started again...)
 
           ville@badger:~$ ipython
           In [1]: l
           NameError: name 'l' is not defined
           In [2]: %store -r
           In [3]: l
           Out[3]: ['hello', 10, 'world']
 
         Usage:
 
         * ``%store``          - Show list of all variables and their current
                                 values
         * ``%store spam``     - Store the *current* value of the variable spam
                                 to disk
         * ``%store -d spam``  - Remove the variable and its value from storage
         * ``%store -z``       - Remove all variables from storage
         * ``%store -r``       - Refresh all variables from store (overwrite
                                 current vals)
         * ``%store -r spam bar`` - Refresh specified variables from store
                                    (delete current val)
         * ``%store foo >a.txt``  - Store value of foo to new file a.txt
         * ``%store foo >>a.txt`` - Append value of foo to file a.txt
 
         It should be noted that if you change the value of a variable, you
         need to %store it again if you want to persist the new value.
 
         Note also that the variables will need to be pickleable; most basic
         python types can be safely %store'd.
 
         Also aliases can be %store'd across sessions.
         """
 
         opts,argsl = self.parse_options(parameter_s,'drz',mode='string')
         args = argsl.split(None,1)
         ip = self.shell
         db = ip.db
         # delete
         if 'd' in opts:
             try:
                 todel = args[0]
             except IndexError:
                 raise UsageError('You must provide the variable to forget')
             else:
                 try:
                     del db['autorestore/' + todel]
                 except:
                     raise UsageError("Can't delete variable '%s'" % todel)
         # reset
         elif 'z' in opts:
             for k in db.keys('autorestore/*'):
                 del db[k]
 
         elif 'r' in opts:
             if args:
                 for arg in args:
                     try:
                         obj = db['autorestore/' + arg]
                     except KeyError:
                         print("no stored variable %s" % arg)
                     else:
                         ip.user_ns[arg] = obj
             else:
                 restore_data(ip)
 
         # run without arguments -> list variables & values
         elif not args:
             vars = db.keys('autorestore/*')
             vars.sort()
             if vars:
                 size = max(map(len, vars))
             else:
                 size = 0
 
             print('Stored variables and their in-db values:')
             fmt = '%-'+str(size)+'s -> %s'
             get = db.get
             for var in vars:
                 justkey = os.path.basename(var)
                 # print 30 first characters from every var
                 print(fmt % (justkey, repr(get(var, '<unavailable>'))[:50]))
 
         # default action - store the variable
         else:
             # %store foo >file.txt or >>file.txt
             if len(args) > 1 and args[1].startswith('>'):
                 fnam = os.path.expanduser(args[1].lstrip('>').lstrip())
                 if args[1].startswith('>>'):
                     fil = open(fnam, 'a')
                 else:
                     fil = open(fnam, 'w')
                 obj = ip.ev(args[0])
                 print("Writing '%s' (%s) to file '%s'." % (args[0],
                   obj.__class__.__name__, fnam))
 
 
                 if not isinstance (obj, string_types):
                     from pprint import pprint
                     pprint(obj, fil)
                 else:
                     fil.write(obj)
                     if not obj.endswith('\n'):
                         fil.write('\n')
 
                 fil.close()
                 return
 
             # %store foo
             try:
                 obj = ip.user_ns[args[0]]
             except KeyError:
                 # it might be an alias
                 name = args[0]
                 try:
                     cmd = ip.alias_manager.retrieve_alias(name)
                 except ValueError:
                     raise UsageError("Unknown variable '%s'" % name)
                 
                 staliases = db.get('stored_aliases',{})
                 staliases[name] = cmd
                 db['stored_aliases'] = staliases
                 print("Alias stored: %s (%s)" % (name, cmd))
                 return
 
             else:
                 modname = getattr(inspect.getmodule(obj), '__name__', '')
                 if modname == '__main__':
                     print(textwrap.dedent("""\
                     Warning:%s is %s
                     Proper storage of interactively declared classes (or instances
                     of those classes) is not possible! Only instances
                     of classes in real modules on file system can be %%store'd.
                     """ % (args[0], obj) ))
                     return
                 #pickled = pickle.dumps(obj)
                 db[ 'autorestore/' + args[0] ] = obj
                 print("Stored '%s' (%s)" % (args[0], obj.__class__.__name__))
 
 
 def load_ipython_extension(ip):
     """Load the extension in IPython."""
     ip.register_magics(StoreMagics)
     

IPython/terminal/ipapp.py

@@ -1,368 +1,371 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """
 The :class:`~IPython.core.application.Application` object for the command
 line :command:`ipython` program.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 from __future__ import absolute_import
 from __future__ import print_function
 
 import logging
 import os
 import sys
+import warnings
 
 from traitlets.config.loader import Config
 from traitlets.config.application import boolean_flag, catch_config_error, Application
 from IPython.core import release
 from IPython.core import usage
 from IPython.core.completer import IPCompleter
 from IPython.core.crashhandler import CrashHandler
 from IPython.core.formatters import PlainTextFormatter
 from IPython.core.history import HistoryManager
 from IPython.core.prompts import PromptManager
 from IPython.core.application import (
     ProfileDir, BaseIPythonApplication, base_flags, base_aliases
 )
 from IPython.core.magics import ScriptMagics
 from IPython.core.shellapp import (
     InteractiveShellApp, shell_flags, shell_aliases
 )
 from IPython.extensions.storemagic import StoreMagics
 from .ptshell import TerminalInteractiveShell
-from IPython.utils import warn
 from IPython.paths import get_ipython_dir
 from traitlets import (
-    Bool, List, Dict,
+    Bool, List, Dict, default, observe,
 )
 
 #-----------------------------------------------------------------------------
 # Globals, utilities and helpers
 #-----------------------------------------------------------------------------
 
 _examples = """
 ipython --matplotlib       # enable matplotlib integration
 ipython --matplotlib=qt    # enable matplotlib integration with qt4 backend
 
 ipython --log-level=DEBUG  # set logging to DEBUG
 ipython --profile=foo      # start with profile foo
 
 ipython profile create foo # create profile foo w/ default config files
 ipython help profile       # show the help for the profile subcmd
 
 ipython locate             # print the path to the IPython directory
 ipython locate profile foo # print the path to the directory for profile `foo`
 """
 
 #-----------------------------------------------------------------------------
 # Crash handler for this application
 #-----------------------------------------------------------------------------
 
 class IPAppCrashHandler(CrashHandler):
     """sys.excepthook for IPython itself, leaves a detailed report on disk."""
 
     def __init__(self, app):
         contact_name = release.author
         contact_email = release.author_email
         bug_tracker = 'https://github.com/ipython/ipython/issues'
         super(IPAppCrashHandler,self).__init__(
             app, contact_name, contact_email, bug_tracker
         )
 
     def make_report(self,traceback):
         """Return a string containing a crash report."""
 
         sec_sep = self.section_sep
         # Start with parent report
         report = [super(IPAppCrashHandler, self).make_report(traceback)]
         # Add interactive-specific info we may have
         rpt_add = report.append
         try:
             rpt_add(sec_sep+"History of session input:")
             for line in self.app.shell.user_ns['_ih']:
                 rpt_add(line)
             rpt_add('\n*** Last line of input (may not be in above history):\n')
             rpt_add(self.app.shell._last_input_line+'\n')
         except:
             pass
 
         return ''.join(report)
 
 #-----------------------------------------------------------------------------
 # Aliases and Flags
 #-----------------------------------------------------------------------------
 flags = dict(base_flags)
 flags.update(shell_flags)
 frontend_flags = {}
 addflag = lambda *args: frontend_flags.update(boolean_flag(*args))
 addflag('autoedit-syntax', 'TerminalInteractiveShell.autoedit_syntax',
         'Turn on auto editing of files with syntax errors.',
         'Turn off auto editing of files with syntax errors.'
 )
 addflag('banner', 'TerminalIPythonApp.display_banner',
         "Display a banner upon starting IPython.",
         "Don't display a banner upon starting IPython."
 )
 addflag('confirm-exit', 'TerminalInteractiveShell.confirm_exit',
     """Set to confirm when you try to exit IPython with an EOF (Control-D
     in Unix, Control-Z/Enter in Windows). By typing 'exit' or 'quit',
     you can force a direct exit without any confirmation.""",
     "Don't prompt the user when exiting."
 )
 addflag('term-title', 'TerminalInteractiveShell.term_title',
     "Enable auto setting the terminal title.",
     "Disable auto setting the terminal title."
 )
 classic_config = Config()
 classic_config.InteractiveShell.cache_size = 0
 classic_config.PlainTextFormatter.pprint = False
 classic_config.PromptManager.in_template = '>>> '
 classic_config.PromptManager.in2_template = '... '
 classic_config.PromptManager.out_template = ''
 classic_config.InteractiveShell.separate_in = ''
 classic_config.InteractiveShell.separate_out = ''
 classic_config.InteractiveShell.separate_out2 = ''
 classic_config.InteractiveShell.colors = 'NoColor'
 classic_config.InteractiveShell.xmode = 'Plain'
 
 frontend_flags['classic']=(
     classic_config,
     "Gives IPython a similar feel to the classic Python prompt."
 )
 # # log doesn't make so much sense this way anymore
 # paa('--log','-l',
 #     action='store_true', dest='InteractiveShell.logstart',
 #     help="Start logging to the default log file (./ipython_log.py).")
 #
 # # quick is harder to implement
 frontend_flags['quick']=(
     {'TerminalIPythonApp' : {'quick' : True}},
     "Enable quick startup with no config files."
 )
 
 frontend_flags['i'] = (
     {'TerminalIPythonApp' : {'force_interact' : True}},
     """If running code from the command line, become interactive afterwards.
     It is often useful to follow this with `--` to treat remaining flags as
     script arguments.
     """
 )
 flags.update(frontend_flags)
 
 aliases = dict(base_aliases)
 aliases.update(shell_aliases)
 
 #-----------------------------------------------------------------------------
 # Main classes and functions
 #-----------------------------------------------------------------------------
 
 
 class LocateIPythonApp(BaseIPythonApplication):
     description = """print the path to the IPython dir"""
     subcommands = Dict(dict(
         profile=('IPython.core.profileapp.ProfileLocate',
             "print the path to an IPython profile directory",
         ),
     ))
     def start(self):
         if self.subapp is not None:
             return self.subapp.start()
         else:
             print(self.ipython_dir)
 
 
 class TerminalIPythonApp(BaseIPythonApplication, InteractiveShellApp):
     name = u'ipython'
     description = usage.cl_usage
     crash_handler_class = IPAppCrashHandler
     examples = _examples
 
     flags = Dict(flags)
     aliases = Dict(aliases)
     classes = List()
+    @default('classes')
     def _classes_default(self):
         """This has to be in a method, for TerminalIPythonApp to be available."""
         return [
             InteractiveShellApp, # ShellApp comes before TerminalApp, because
             self.__class__,      # it will also affect subclasses (e.g. QtConsole)
             TerminalInteractiveShell,
             PromptManager,
             HistoryManager,
             ProfileDir,
             PlainTextFormatter,
             IPCompleter,
             ScriptMagics,
             StoreMagics,
         ]
 
     deprecated_subcommands = dict(
         qtconsole=('qtconsole.qtconsoleapp.JupyterQtConsoleApp',
             """DEPRECATED, Will be removed in IPython 6.0 : Launch the Jupyter Qt Console."""
         ),
         notebook=('notebook.notebookapp.NotebookApp',
             """DEPRECATED, Will be removed in IPython 6.0 : Launch the Jupyter HTML Notebook Server."""
         ),
         console=('jupyter_console.app.ZMQTerminalIPythonApp',
             """DEPRECATED, Will be removed in IPython 6.0 : Launch the Jupyter terminal-based Console."""
         ),
         nbconvert=('nbconvert.nbconvertapp.NbConvertApp',
             "DEPRECATED, Will be removed in IPython 6.0 : Convert notebooks to/from other formats."
         ),
         trust=('nbformat.sign.TrustNotebookApp',
             "DEPRECATED, Will be removed in IPython 6.0 : Sign notebooks to trust their potentially unsafe contents at load."
         ),
         kernelspec=('jupyter_client.kernelspecapp.KernelSpecApp',
             "DEPRECATED, Will be removed in IPython 6.0 : Manage Jupyter kernel specifications."
         ),
     )
     subcommands = dict(
         profile = ("IPython.core.profileapp.ProfileApp",
             "Create and manage IPython profiles."
         ),
         kernel = ("ipykernel.kernelapp.IPKernelApp",
             "Start a kernel without an attached frontend."
         ),
         locate=('IPython.terminal.ipapp.LocateIPythonApp',
             LocateIPythonApp.description
         ),
         history=('IPython.core.historyapp.HistoryApp',
             "Manage the IPython history database."
         ),
     )
     deprecated_subcommands['install-nbextension'] = (
         "notebook.nbextensions.InstallNBExtensionApp",
         "DEPRECATED, Will be removed in IPython 6.0 : Install Jupyter notebook extension files"
     )
     subcommands.update(deprecated_subcommands)
 
     # *do* autocreate requested profile, but don't create the config file.
     auto_create=Bool(True)
     # configurables
-    quick = Bool(False, config=True,
+    quick = Bool(False,
         help="""Start IPython quickly by skipping the loading of config files."""
-    )
-    def _quick_changed(self, name, old, new):
-        if new:
+    ).tag(config=True)
+    @observe('quick')
+    def _quick_changed(self, change):
+        if change['new']:
             self.load_config_file = lambda *a, **kw: None
 
-    display_banner = Bool(True, config=True,
+    display_banner = Bool(True,
         help="Whether to display a banner upon starting IPython."
-    )
+    ).tag(config=True)
 
     # if there is code of files to run from the cmd line, don't interact
     # unless the --i flag (App.force_interact) is true.
-    force_interact = Bool(False, config=True,
+    force_interact = Bool(False,
         help="""If a command or file is given via the command-line,
         e.g. 'ipython foo.py', start an interactive shell after executing the
         file or command."""
-    )
-    def _force_interact_changed(self, name, old, new):
-        if new:
+    ).tag(config=True)
+    @observe('force_interact')
+    def _force_interact_changed(self, change):
+        if change['new']:
             self.interact = True
 
-    def _file_to_run_changed(self, name, old, new):
+    @observe('file_to_run', 'code_to_run', 'module_to_run')
+    def _file_to_run_changed(self, change):
+        new = change['new']
         if new:
             self.something_to_run = True
         if new and not self.force_interact:
                 self.interact = False
-    _code_to_run_changed = _file_to_run_changed
-    _module_to_run_changed = _file_to_run_changed
 
     # internal, not-configurable
     something_to_run=Bool(False)
 
     def parse_command_line(self, argv=None):
         """override to allow old '-pylab' flag with deprecation warning"""
 
         argv = sys.argv[1:] if argv is None else argv
 
         if '-pylab' in argv:
             # deprecated `-pylab` given,
             # warn and transform into current syntax
             argv = argv[:] # copy, don't clobber
             idx = argv.index('-pylab')
-            warn.warn("`-pylab` flag has been deprecated.\n"
+            warnings.warn("`-pylab` flag has been deprecated.\n"
             "    Use `--matplotlib <backend>` and import pylab manually.")
             argv[idx] = '--pylab'
 
         return super(TerminalIPythonApp, self).parse_command_line(argv)
     
     @catch_config_error
     def initialize(self, argv=None):
         """Do actions after construct, but before starting the app."""
         super(TerminalIPythonApp, self).initialize(argv)
         if self.subapp is not None:
             # don't bother initializing further, starting subapp
             return
         # print self.extra_args
         if self.extra_args and not self.something_to_run:
             self.file_to_run = self.extra_args[0]
         self.init_path()
         # create the shell
         self.init_shell()
         # and draw the banner
         self.init_banner()
         # Now a variety of things that happen after the banner is printed.
         self.init_gui_pylab()
         self.init_extensions()
         self.init_code()
 
     def init_shell(self):
         """initialize the InteractiveShell instance"""
         # Create an InteractiveShell instance.
         # shell.display_banner should always be False for the terminal
         # based app, because we call shell.show_banner() by hand below
         # so the banner shows *before* all extension loading stuff.
         self.shell = TerminalInteractiveShell.instance(parent=self,
                         profile_dir=self.profile_dir,
                         ipython_dir=self.ipython_dir, user_ns=self.user_ns)
         self.shell.configurables.append(self)
 
     def init_banner(self):
         """optionally display the banner"""
         if self.display_banner and self.interact:
             self.shell.show_banner()
         # Make sure there is a space below the banner.
         if self.log_level <= logging.INFO: print()
 
     def _pylab_changed(self, name, old, new):
         """Replace --pylab='inline' with --pylab='auto'"""
         if new == 'inline':
-            warn.warn("'inline' not available as pylab backend, "
+            warnings.warn("'inline' not available as pylab backend, "
                       "using 'auto' instead.")
             self.pylab = 'auto'
 
     def start(self):
         if self.subapp is not None:
             return self.subapp.start()
         # perform any prexec steps:
         if self.interact:
             self.log.debug("Starting IPython's mainloop...")
             self.shell.mainloop()
         else:
             self.log.debug("IPython not interactive...")
 
 def load_default_config(ipython_dir=None):
     """Load the default config file from the default ipython_dir.
 
     This is useful for embedded shells.
     """
     if ipython_dir is None:
         ipython_dir = get_ipython_dir()
 
     profile_dir = os.path.join(ipython_dir, 'profile_default')
 
     config = Config()
     for cf in Application._load_config_files("ipython_config", path=profile_dir):
         config.update(cf)
 
     return config
 
 launch_new_instance = TerminalIPythonApp.launch_instance
 
 
 if __name__ == '__main__':
     launch_new_instance()

IPython/terminal/ptshell.py

@@ -1,464 +1,467 b''
 """IPython terminal interface using prompt_toolkit in place of readline"""
 from __future__ import print_function
 
 import os
 import sys
 import signal
 import unicodedata
 from warnings import warn
 from wcwidth import wcwidth
 
 from IPython.core.error import TryNext
 from IPython.core.interactiveshell import InteractiveShell
 from IPython.utils.py3compat import PY3, cast_unicode_py2, input
 from IPython.utils.terminal import toggle_set_term_title, set_term_title
 from IPython.utils.process import abbrev_cwd
-from traitlets import Bool, CBool, Unicode, Dict, Integer, observe
+from traitlets import Bool, Unicode, Dict, Integer, observe
 
 from prompt_toolkit.completion import Completer, Completion
 from prompt_toolkit.enums import DEFAULT_BUFFER, SEARCH_BUFFER, EditingMode
 from prompt_toolkit.filters import HasFocus, HasSelection, Condition, ViInsertMode, EmacsInsertMode
 from prompt_toolkit.history import InMemoryHistory
 from prompt_toolkit.shortcuts import create_prompt_application, create_eventloop, create_prompt_layout
 from prompt_toolkit.interface import CommandLineInterface
 from prompt_toolkit.key_binding.manager import KeyBindingManager
 from prompt_toolkit.keys import Keys
 from prompt_toolkit.layout.lexers import Lexer
 from prompt_toolkit.layout.lexers import PygmentsLexer
 from prompt_toolkit.styles import PygmentsStyle, DynamicStyle
 
 from pygments.styles import get_style_by_name, get_all_styles
 from pygments.lexers import Python3Lexer, BashLexer, PythonLexer
 from pygments.token import Token
 
 from .pt_inputhooks import get_inputhook_func
 from .interactiveshell import get_default_editor, TerminalMagics
 
 
 class IPythonPTCompleter(Completer):
     """Adaptor to provide IPython completions to prompt_toolkit"""
     def __init__(self, ipy_completer):
         self.ipy_completer = ipy_completer
 
     def get_completions(self, document, complete_event):
         if not document.current_line.strip():
             return
 
         used, matches = self.ipy_completer.complete(
                             line_buffer=document.current_line,
                             cursor_pos=document.cursor_position_col
         )
         start_pos = -len(used)
         for m in matches:
             m = unicodedata.normalize('NFC', m)
 
             # When the first character of the completion has a zero length,
             # then it's probably a decomposed unicode character. E.g. caused by
             # the "\dot" completion. Try to compose again with the previous
             # character.
             if wcwidth(m[0]) == 0:
                 if document.cursor_position + start_pos > 0:
                     char_before = document.text[document.cursor_position + start_pos - 1]
                     m = unicodedata.normalize('NFC', char_before + m)
 
                     # Yield the modified completion instead, if this worked.
                     if wcwidth(m[0:1]) == 1:
                         yield Completion(m, start_position=start_pos - 1)
                         continue
 
             # TODO: Use Jedi to determine meta_text
             # (Jedi currently has a bug that results in incorrect information.)
             # meta_text = ''
             # yield Completion(m, start_position=start_pos,
             #                  display_meta=meta_text)
             yield Completion(m, start_position=start_pos)
 
 class IPythonPTLexer(Lexer):
     """
     Wrapper around PythonLexer and BashLexer.
     """
     def __init__(self):
         self.python_lexer = PygmentsLexer(Python3Lexer if PY3 else PythonLexer)
         self.shell_lexer = PygmentsLexer(BashLexer)
 
     def lex_document(self, cli, document):
         if document.text.startswith('!'):
             return self.shell_lexer.lex_document(cli, document)
         else:
             return self.python_lexer.lex_document(cli, document)
 
 
 class TerminalInteractiveShell(InteractiveShell):
     colors_force = True
 
     space_for_menu = Integer(6, help='Number of line at the bottom of the screen '
                                                   'to reserve for the completion menu'
                             ).tag(config=True)
 
     def _space_for_menu_changed(self, old, new):
         self._update_layout()
 
     pt_cli = None
 
-    autoedit_syntax = CBool(False).tag(config=True,
-                            help="auto editing of files with syntax errors.")
+    autoedit_syntax = Bool(False,
+        help="auto editing of files with syntax errors.",
+    ).tag(config=True)
+
 
-    confirm_exit = CBool(True).tag(config=True,
+    confirm_exit = Bool(True,
         help="""
         Set to confirm when you try to exit IPython with an EOF (Control-D
         in Unix, Control-Z/Enter in Windows). By typing 'exit' or 'quit',
         you can force a direct exit without any confirmation.""",
-    )
+    ).tag(config=True)
+
     editing_mode = Unicode('emacs',
         help="Shortcut style to use at the prompt. 'vi' or 'emacs'.",
     ).tag(config=True)
 
     mouse_support = Bool(False,
         help="Enable mouse support in the prompt"
     ).tag(config=True)
 
     highlighting_style = Unicode('default',
             help="The name of a Pygments style to use for syntax highlighting: \n %s" % ', '.join(get_all_styles())
     ).tag(config=True)
 
-    def _highlighting_style_changed(self, old, new):
+    
+    @observe('highlighting_style')
+    def _highlighting_style_changed(self, change):
         self._style = self._make_style_from_name(self.highlighting_style)
 
     highlighting_style_overrides = Dict(
         help="Override highlighting format for specific tokens"
     ).tag(config=True)
 
     editor = Unicode(get_default_editor(),
         help="Set the editor used by IPython (default to $EDITOR/vi/notepad)."
     ).tag(config=True)
     
     term_title = Bool(True,
         help="Automatically set the terminal title"
     ).tag(config=True)
 
     display_completions_in_columns = Bool(False,
         help="Display a multi column completion menu.",
     ).tag(config=True)
 
-    @observe('term_title')
-    def _term_title_changed(self, change):
-        self.init_term_title()
     
-    def init_term_title(self):
+    @observe('term_title')
+    def init_term_title(self, change=None):
         # Enable or disable the terminal title.
         if self.term_title:
             toggle_set_term_title(True)
             set_term_title('IPython: ' + abbrev_cwd())
         else:
             toggle_set_term_title(False)
 
     def get_prompt_tokens(self, cli):
         return [
             (Token.Prompt, 'In ['),
             (Token.PromptNum, str(self.execution_count)),
             (Token.Prompt, ']: '),
         ]
 
     def get_continuation_tokens(self, cli, width):
         return [
             (Token.Prompt, (' ' * (width - 5)) + '...: '),
         ]
 
     def init_prompt_toolkit_cli(self):
         if ('IPY_TEST_SIMPLE_PROMPT' in os.environ) or not sys.stdin.isatty():
             # Fall back to plain non-interactive output for tests.
             # This is very limited, and only accepts a single line.
             def prompt():
                 return cast_unicode_py2(input('In [%d]: ' % self.execution_count))
             self.prompt_for_code = prompt
             return
 
         kbmanager = KeyBindingManager.for_prompt()
         insert_mode = ViInsertMode() | EmacsInsertMode()
         # Ctrl+J == Enter, seemingly
         @kbmanager.registry.add_binding(Keys.ControlJ,
                             filter=(HasFocus(DEFAULT_BUFFER)
                                     & ~HasSelection()
                                     & insert_mode
                                    ))
         def _(event):
             b = event.current_buffer
             d = b.document
             if not (d.on_last_line or d.cursor_position_row >= d.line_count
                                            - d.empty_line_count_at_the_end()):
                 b.newline()
                 return
 
             status, indent = self.input_splitter.check_complete(d.text)
 
             if (status != 'incomplete') and b.accept_action.is_returnable:
                 b.accept_action.validate_and_handle(event.cli, b)
             else:
                 b.insert_text('\n' + (' ' * (indent or 0)))
 
         @kbmanager.registry.add_binding(Keys.ControlC, filter=HasFocus(DEFAULT_BUFFER))
         def _reset_buffer(event):
             event.current_buffer.reset()
 
         @kbmanager.registry.add_binding(Keys.ControlC, filter=HasFocus(SEARCH_BUFFER))
         def _reset_search_buffer(event):
             if event.current_buffer.document.text:
                 event.current_buffer.reset()
             else:
                 event.cli.push_focus(DEFAULT_BUFFER)
 
         supports_suspend = Condition(lambda cli: hasattr(signal, 'SIGTSTP'))
 
         @kbmanager.registry.add_binding(Keys.ControlZ, filter=supports_suspend)
         def _suspend_to_bg(event):
             event.cli.suspend_to_background()
 
         @Condition
         def cursor_in_leading_ws(cli):
             before = cli.application.buffer.document.current_line_before_cursor
             return (not before) or before.isspace()
 
         # Ctrl+I == Tab
         @kbmanager.registry.add_binding(Keys.ControlI,
                             filter=(HasFocus(DEFAULT_BUFFER)
                                     & ~HasSelection()
                                     & insert_mode
                                     & cursor_in_leading_ws
                                    ))
         def _indent_buffer(event):
             event.current_buffer.insert_text(' ' * 4)
 
         # Pre-populate history from IPython's history database
         history = InMemoryHistory()
         last_cell = u""
         for __, ___, cell in self.history_manager.get_tail(self.history_load_length,
                                                         include_latest=True):
             # Ignore blank lines and consecutive duplicates
             cell = cell.rstrip()
             if cell and (cell != last_cell):
                 history.append(cell)
 
         self._style = self._make_style_from_name(self.highlighting_style)
         style = DynamicStyle(lambda: self._style)
 
         editing_mode = getattr(EditingMode, self.editing_mode.upper())
 
         self._app = create_prompt_application(
                             editing_mode=editing_mode,
                             key_bindings_registry=kbmanager.registry,
                             history=history,
                             completer=IPythonPTCompleter(self.Completer),
                             enable_history_search=True,
                             style=style,
                             mouse_support=self.mouse_support,
                             **self._layout_options()
         )
         self.pt_cli = CommandLineInterface(self._app,
                            eventloop=create_eventloop(self.inputhook))
 
     def _make_style_from_name(self, name):
         """
         Small wrapper that make an IPython compatible style from a style name
 
         We need that to add style for prompt ... etc. 
         """
         style_cls = get_style_by_name(name)
         style_overrides = {
             Token.Prompt: '#009900',
             Token.PromptNum: '#00ff00 bold',
         }
         if name == 'default':
             style_cls = get_style_by_name('default')
             # The default theme needs to be visible on both a dark background
             # and a light background, because we can't tell what the terminal
             # looks like. These tweaks to the default theme help with that.
             style_overrides.update({
                 Token.Number: '#007700',
                 Token.Operator: 'noinherit',
                 Token.String: '#BB6622',
                 Token.Name.Function: '#2080D0',
                 Token.Name.Class: 'bold #2080D0',
                 Token.Name.Namespace: 'bold #2080D0',
             })
         style_overrides.update(self.highlighting_style_overrides)
         style = PygmentsStyle.from_defaults(pygments_style_cls=style_cls,
                                             style_dict=style_overrides)
 
         return style
 
     def _layout_options(self):
         """
         Return the current layout option for the current Terminal InteractiveShell
         """
         return {
                 'lexer':IPythonPTLexer(),
                 'reserve_space_for_menu':self.space_for_menu,
                 'get_prompt_tokens':self.get_prompt_tokens,
                 'get_continuation_tokens':self.get_continuation_tokens,
                 'multiline':True,
                 'display_completions_in_columns': self.display_completions_in_columns,
                 }
 
     def _update_layout(self):
         """
         Ask for a re computation of the application layout, if for example ,
         some configuration options have changed.
         """
         self._app.layout = create_prompt_layout(**self._layout_options())
 
     def prompt_for_code(self):
         document = self.pt_cli.run(
             pre_run=self.pre_prompt, reset_current_buffer=True)
         return document.text
 
     def init_io(self):
         if sys.platform not in {'win32', 'cli'}:
             return
 
         import colorama
         colorama.init()
 
         # For some reason we make these wrappers around stdout/stderr.
         # For now, we need to reset them so all output gets coloured.
         # https://github.com/ipython/ipython/issues/8669
         from IPython.utils import io
         io.stdout = io.IOStream(sys.stdout)
         io.stderr = io.IOStream(sys.stderr)
 
     def init_magics(self):
         super(TerminalInteractiveShell, self).init_magics()
         self.register_magics(TerminalMagics)
 
     def init_alias(self):
         # The parent class defines aliases that can be safely used with any
         # frontend.
         super(TerminalInteractiveShell, self).init_alias()
 
         # Now define aliases that only make sense on the terminal, because they
         # need direct access to the console in a way that we can't emulate in
         # GUI or web frontend
         if os.name == 'posix':
             for cmd in ['clear', 'more', 'less', 'man']:
                 self.alias_manager.soft_define_alias(cmd, cmd)
 
 
     def __init__(self, *args, **kwargs):
         super(TerminalInteractiveShell, self).__init__(*args, **kwargs)
         self.init_prompt_toolkit_cli()
         self.init_term_title()
         self.keep_running = True
 
     def ask_exit(self):
         self.keep_running = False
 
     rl_next_input = None
 
     def pre_prompt(self):
         if self.rl_next_input:
             self.pt_cli.application.buffer.text = cast_unicode_py2(self.rl_next_input)
             self.rl_next_input = None
 
     def interact(self):
         while self.keep_running:
             print(self.separate_in, end='')
 
             try:
                 code = self.prompt_for_code()
             except EOFError:
                 if (not self.confirm_exit) \
                         or self.ask_yes_no('Do you really want to exit ([y]/n)?','y','n'):
                     self.ask_exit()
 
             else:
                 if code:
                     self.run_cell(code, store_history=True)
                     if self.autoedit_syntax and self.SyntaxTB.last_syntax_error:
                         self.edit_syntax_error()
 
     def mainloop(self):
         # An extra layer of protection in case someone mashing Ctrl-C breaks
         # out of our internal code.
         while True:
             try:
                 self.interact()
                 break
             except KeyboardInterrupt:
                 print("\nKeyboardInterrupt escaped interact()\n")
 
     _inputhook = None
     def inputhook(self, context):
         if self._inputhook is not None:
             self._inputhook(context)
 
     def enable_gui(self, gui=None):
         if gui:
             self._inputhook = get_inputhook_func(gui)
         else:
             self._inputhook = None
 
     # Methods to support auto-editing of SyntaxErrors:
 
     def edit_syntax_error(self):
         """The bottom half of the syntax error handler called in the main loop.
 
         Loop until syntax error is fixed or user cancels.
         """
 
         while self.SyntaxTB.last_syntax_error:
             # copy and clear last_syntax_error
             err = self.SyntaxTB.clear_err_state()
             if not self._should_recompile(err):
                 return
             try:
                 # may set last_syntax_error again if a SyntaxError is raised
                 self.safe_execfile(err.filename, self.user_ns)
             except:
                 self.showtraceback()
             else:
                 try:
                     with open(err.filename) as f:
                         # This should be inside a display_trap block and I
                         # think it is.
                         sys.displayhook(f.read())
                 except:
                     self.showtraceback()
 
     def _should_recompile(self, e):
         """Utility routine for edit_syntax_error"""
 
         if e.filename in ('<ipython console>', '<input>', '<string>',
                           '<console>', '<BackgroundJob compilation>',
                           None):
             return False
         try:
             if (self.autoedit_syntax and
                     not self.ask_yes_no(
                         'Return to editor to correct syntax error? '
                         '[Y/n] ', 'y')):
                 return False
         except EOFError:
             return False
 
         def int0(x):
             try:
                 return int(x)
             except TypeError:
                 return 0
 
         # always pass integer line and offset values to editor hook
         try:
             self.hooks.fix_error_editor(e.filename,
                                         int0(e.lineno), int0(e.offset),
                                         e.msg)
         except TryNext:
             warn('Could not open editor')
             return False
         return True
 
     # Run !system commands directly, not through pipes, so terminal programs
     # work correctly.
     system = InteractiveShell.system_raw
 
 
 if __name__ == '__main__':
     TerminalInteractiveShell.instance().interact()

IPython/utils/colorable.py

@@ -1,26 +1,26 b''
 #*****************************************************************************
 # Copyright (C) 2016 The IPython Team <[e-mail]>
 #
 # 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
 
 """
 Color managing related utilities
 """
 
 import pygments
 
 from traitlets.config import Configurable
 from traitlets import Unicode
 
 
 available_themes = lambda : [s for s in pygments.styles.get_all_styles()]+['NoColor','LightBG','Linux']
 
 class Colorable(Configurable):
     """
     A subclass of configurable for all the classes that have a `default_scheme`
     """
-    default_style=Unicode('lightbg', config=True)
+    default_style=Unicode('lightbg').tag(config=True)