DOC: More autoreformatting of docstrings.

Also add some configuration to ignore some files.

IPython/core/displayhook.py

@@ -1,325 +1,325 b''
 # -*- coding: utf-8 -*-
 """Displayhook for IPython.
 
 This defines a callable class that IPython uses for `sys.displayhook`.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import builtins as builtin_mod
 import sys
 import io as _io
 import tokenize
 
 from traitlets.config.configurable import Configurable
 from traitlets import Instance, Float
 from warnings import warn
 
 # TODO: Move the various attributes (cache_size, [others now moved]). Some
 # of these are also attributes of InteractiveShell. They should be on ONE object
 # only and the other objects should ask that one object for their values.
 
 class DisplayHook(Configurable):
     """The custom IPython displayhook to replace sys.displayhook.
 
     This class does many things, but the basic idea is that it is a callable
     that gets called anytime user code returns a value.
     """
 
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC',
                      allow_none=True)
     exec_result = Instance('IPython.core.interactiveshell.ExecutionResult',
                            allow_none=True)
     cull_fraction = Float(0.2)
 
     def __init__(self, shell=None, cache_size=1000, **kwargs):
         super(DisplayHook, self).__init__(shell=shell, **kwargs)
         cache_size_min = 3
         if cache_size <= 0:
             self.do_full_cache = 0
             cache_size = 0
         elif cache_size < cache_size_min:
             self.do_full_cache = 0
             cache_size = 0
             warn('caching was disabled (min value for cache size is %s).' %
                  cache_size_min,stacklevel=3)
         else:
             self.do_full_cache = 1
 
         self.cache_size = cache_size
 
         # we need a reference to the user-level namespace
         self.shell = shell
         
         self._,self.__,self.___ = '','',''
 
         # these are deliberately global:
         to_user_ns = {'_':self._,'__':self.__,'___':self.___}
         self.shell.user_ns.update(to_user_ns)
 
     @property
     def prompt_count(self):
         return self.shell.execution_count
 
     #-------------------------------------------------------------------------
     # Methods used in __call__. Override these methods to modify the behavior
     # of the displayhook.
     #-------------------------------------------------------------------------
 
     def check_for_underscore(self):
         """Check if the user has set the '_' variable by hand."""
         # If something injected a '_' variable in __builtin__, delete
         # ipython's automatic one so we don't clobber that.  gettext() in
         # particular uses _, so we need to stay away from it.
         if '_' in builtin_mod.__dict__:
             try:
                 user_value = self.shell.user_ns['_']
                 if user_value is not self._:
                     return
                 del self.shell.user_ns['_']
             except KeyError:
                 pass
 
     def quiet(self):
         """Should we silence the display hook because of ';'?"""
         # do not print output if input ends in ';'
         
         try:
             cell = self.shell.history_manager.input_hist_parsed[-1]
         except IndexError:
             # some uses of ipshellembed may fail here
             return False
         
         sio = _io.StringIO(cell)
         tokens = list(tokenize.generate_tokens(sio.readline))
 
         for token in reversed(tokens):
             if token[0] in (tokenize.ENDMARKER, tokenize.NL, tokenize.NEWLINE, tokenize.COMMENT):
                 continue
             if (token[0] == tokenize.OP) and (token[1] == ';'):
                 return True
             else:
                 return False
 
     def start_displayhook(self):
         """Start the displayhook, initializing resources."""
         pass
 
     def write_output_prompt(self):
         """Write the output prompt.
 
         The default implementation simply writes the prompt to
         ``sys.stdout``.
         """
         # Use write, not print which adds an extra space.
         sys.stdout.write(self.shell.separate_out)
         outprompt = 'Out[{}]: '.format(self.shell.execution_count)
         if self.do_full_cache:
             sys.stdout.write(outprompt)
 
     def compute_format_data(self, result):
         """Compute format data of the object to be displayed.
 
         The format data is a generalization of the :func:`repr` of an object.
         In the default implementation the format data is a :class:`dict` of
         key value pair where the keys are valid MIME types and the values
         are JSON'able data structure containing the raw data for that MIME
         type. It is up to frontends to determine pick a MIME to to use and
         display that data in an appropriate manner.
 
         This method only computes the format data for the object and should
         NOT actually print or write that to a stream.
 
         Parameters
         ----------
         result : object
             The Python object passed to the display hook, whose format will be
             computed.
 
         Returns
         -------
         (format_dict, md_dict) : dict
             format_dict is a :class:`dict` whose keys are valid MIME types and values are
             JSON'able raw data for that MIME type. It is recommended that
             all return values of this should always include the "text/plain"
             MIME type representation of the object.
             md_dict is a :class:`dict` with the same MIME type keys
             of metadata associated with each output.
-            
+
         """
         return self.shell.display_formatter.format(result)
 
     # This can be set to True by the write_output_prompt method in a subclass
     prompt_end_newline = False
 
     def write_format_data(self, format_dict, md_dict=None) -> None:
         """Write the format data dict to the frontend.
 
         This default version of this method simply writes the plain text
         representation of the object to ``sys.stdout``. Subclasses should
         override this method to send the entire `format_dict` to the
         frontends.
 
         Parameters
         ----------
         format_dict : dict
             The format dict for the object passed to `sys.displayhook`.
         md_dict : dict (optional)
             The metadata dict to be associated with the display data.
         """
         if 'text/plain' not in format_dict:
             # nothing to do
             return
         # We want to print because we want to always make sure we have a
         # newline, even if all the prompt separators are ''. This is the
         # standard IPython behavior.
         result_repr = format_dict['text/plain']
         if '\n' in result_repr:
             # So that multi-line strings line up with the left column of
             # the screen, instead of having the output prompt mess up
             # their first line.
             # We use the prompt template instead of the expanded prompt
             # because the expansion may add ANSI escapes that will interfere
             # with our ability to determine whether or not we should add
             # a newline.
             if not self.prompt_end_newline:
                 # But avoid extraneous empty lines.
                 result_repr = '\n' + result_repr
 
         try:
             print(result_repr)
         except UnicodeEncodeError:
             # If a character is not supported by the terminal encoding replace
             # it with its \u or \x representation
             print(result_repr.encode(sys.stdout.encoding,'backslashreplace').decode(sys.stdout.encoding))
 
     def update_user_ns(self, result):
         """Update user_ns with various things like _, __, _1, etc."""
 
         # Avoid recursive reference when displaying _oh/Out
         if self.cache_size and result is not self.shell.user_ns['_oh']:
             if len(self.shell.user_ns['_oh']) >= self.cache_size and self.do_full_cache:
                 self.cull_cache()
 
             # Don't overwrite '_' and friends if '_' is in __builtin__
             # (otherwise we cause buggy behavior for things like gettext). and
             # do not overwrite _, __ or ___ if one of these has been assigned
             # by the user.
             update_unders = True
             for unders in ['_'*i for i in range(1,4)]:
                 if not unders in self.shell.user_ns:
                     continue
                 if getattr(self, unders) is not self.shell.user_ns.get(unders):
                     update_unders = False
 
             self.___ = self.__
             self.__ = self._
             self._ = result
 
             if ('_' not in builtin_mod.__dict__) and (update_unders):
                 self.shell.push({'_':self._,
                                  '__':self.__,
                                 '___':self.___}, interactive=False)
 
             # hackish access to top-level  namespace to create _1,_2... dynamically
             to_main = {}
             if self.do_full_cache:
                 new_result = '_%s' % self.prompt_count
                 to_main[new_result] = result
                 self.shell.push(to_main, interactive=False)
                 self.shell.user_ns['_oh'][self.prompt_count] = result
 
     def fill_exec_result(self, result):
         if self.exec_result is not None:
             self.exec_result.result = result
 
     def log_output(self, format_dict):
         """Log the output."""
         if 'text/plain' not in format_dict:
             # nothing to do
             return
         if self.shell.logger.log_output:
             self.shell.logger.log_write(format_dict['text/plain'], 'output')
         self.shell.history_manager.output_hist_reprs[self.prompt_count] = \
                                                     format_dict['text/plain']
 
     def finish_displayhook(self):
         """Finish up all displayhook activities."""
         sys.stdout.write(self.shell.separate_out2)
         sys.stdout.flush()
 
     def __call__(self, result=None):
         """Printing with history cache management.
 
         This is invoked every time the interpreter needs to print, and is
         activated by setting the variable sys.displayhook to it.
         """
         self.check_for_underscore()
         if result is not None and not self.quiet():
             self.start_displayhook()
             self.write_output_prompt()
             format_dict, md_dict = self.compute_format_data(result)
             self.update_user_ns(result)
             self.fill_exec_result(result)
             if format_dict:
                 self.write_format_data(format_dict, md_dict)
                 self.log_output(format_dict)
             self.finish_displayhook()
 
     def cull_cache(self):
         """Output cache is full, cull the oldest entries"""
         oh = self.shell.user_ns.get('_oh', {})
         sz = len(oh)
         cull_count = max(int(sz * self.cull_fraction), 2)
         warn('Output cache limit (currently {sz} entries) hit.\n'
              'Flushing oldest {cull_count} entries.'.format(sz=sz, cull_count=cull_count))
         
         for i, n in enumerate(sorted(oh)):
             if i >= cull_count:
                 break
             self.shell.user_ns.pop('_%i' % n, None)
             oh.pop(n, None)
         
 
     def flush(self):
         if not self.do_full_cache:
             raise ValueError("You shouldn't have reached the cache flush "
                              "if full caching is not enabled!")
         # delete auto-generated vars from global namespace
 
         for n in range(1,self.prompt_count + 1):
             key = '_'+repr(n)
             try:
                 del self.shell.user_ns[key]
             except: pass
         # In some embedded circumstances, the user_ns doesn't have the
         # '_oh' key set up.
         oh = self.shell.user_ns.get('_oh', None)
         if oh is not None:
             oh.clear()
 
         # Release our own references to objects:
         self._, self.__, self.___ = '', '', ''
 
         if '_' not in builtin_mod.__dict__:
             self.shell.user_ns.update({'_':self._,'__':self.__,'___':self.___})
         import gc
         # TODO: Is this really needed?
         # IronPython blocks here forever
         if sys.platform != "cli":
             gc.collect()
 
 
 class CapturingDisplayHook(object):
     def __init__(self, shell, outputs=None):
         self.shell = shell
         if outputs is None:
             outputs = []
         self.outputs = outputs
 
     def __call__(self, result=None):
         if result is None:
             return
         format_dict, md_dict = self.shell.display_formatter.format(result)
         self.outputs.append({ 'data': format_dict, 'metadata': md_dict })

IPython/core/displaypub.py

@@ -1,138 +1,138 b''
 """An interface for publishing rich data to frontends.
 
 There are two components of the display system:
 
 * Display formatters, which take a Python object and compute the
   representation of the object in various formats (text, HTML, SVG, etc.).
 * The display publisher that is used to send the representation data to the
   various frontends.
 
 This module defines the logic display publishing. The display publisher uses
 the ``display_data`` message type that is defined in the IPython messaging
 spec.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 
 import sys
 
 from traitlets.config.configurable import Configurable
 from traitlets import List
 
 # This used to be defined here - it is imported for backwards compatibility
 from .display_functions import publish_display_data
 
 #-----------------------------------------------------------------------------
 # Main payload class
 #-----------------------------------------------------------------------------
 
 
 class DisplayPublisher(Configurable):
     """A traited class that publishes display data to frontends.
 
     Instances of this class are created by the main IPython object and should
     be accessed there.
     """
 
     def __init__(self, shell=None, *args, **kwargs):
         self.shell = shell
         super().__init__(*args, **kwargs)
 
     def _validate_data(self, data, metadata=None):
         """Validate the display data.
 
         Parameters
         ----------
         data : dict
             The formata data dictionary.
         metadata : dict
             Any metadata for the data.
         """
 
         if not isinstance(data, dict):
             raise TypeError('data must be a dict, got: %r' % data)
         if metadata is not None:
             if not isinstance(metadata, dict):
                 raise TypeError('metadata must be a dict, got: %r' % data)
 
     # use * to indicate transient, update are keyword-only
     def publish(self, data, metadata=None, source=None, *, transient=None, update=False, **kwargs) -> None:
         """Publish data and metadata to all frontends.
 
         See the ``display_data`` message in the messaging documentation for
         more details about this message type.
 
         The following MIME types are currently implemented:
 
         * text/plain
         * text/html
         * text/markdown
         * text/latex
         * application/json
         * application/javascript
         * image/png
         * image/jpeg
         * image/svg+xml
 
         Parameters
         ----------
         data : dict
             A dictionary having keys that are valid MIME types (like
             'text/plain' or 'image/svg+xml') and values that are the data for
             that MIME type. The data itself must be a JSON'able data
             structure. Minimally all data should have the 'text/plain' data,
             which can be displayed by all frontends. If more than the plain
             text is given, it is up to the frontend to decide which
             representation to use.
         metadata : dict
             A dictionary for metadata related to the data. This can contain
             arbitrary key, value pairs that frontends can use to interpret
             the data.  Metadata specific to each mime-type can be specified
             in the metadata dict with the same mime-type keys as
             the data itself.
         source : str, deprecated
             Unused.
-        transient: dict, keyword-only
+        transient : dict, keyword-only
             A dictionary for transient data.
             Data in this dictionary should not be persisted as part of saving this output.
             Examples include 'display_id'.
-        update: bool, keyword-only, default: False
+        update : bool, keyword-only, default: False
             If True, only update existing outputs with the same display_id,
             rather than creating a new output.
         """
 
         handlers = {}
         if self.shell is not None:
             handlers = getattr(self.shell, 'mime_renderers', {})
 
         for mime, handler in handlers.items():
             if mime in data:
                 handler(data[mime], metadata.get(mime, None))
                 return
 
         if 'text/plain' in data:
             print(data['text/plain'])
 
     def clear_output(self, wait=False):
         """Clear the output of the cell receiving output."""
         print('\033[2K\r', end='')
         sys.stdout.flush()
         print('\033[2K\r', end='')
         sys.stderr.flush()
 
 
 class CapturingDisplayPublisher(DisplayPublisher):
     """A DisplayPublisher that stores"""
     outputs = List()
 
     def publish(self, data, metadata=None, source=None, *, transient=None, update=False):
         self.outputs.append({'data':data, 'metadata':metadata,
                              'transient':transient, 'update':update})
 
     def clear_output(self, wait=False):
         super(CapturingDisplayPublisher, self).clear_output(wait)
 
         # empty the list, *do not* reassign a new list
         self.outputs.clear()

IPython/core/events.py

@@ -1,161 +1,161 b''
 """Infrastructure for registering and firing callbacks on application events.
 
 Unlike :mod:`IPython.core.hooks`, which lets end users set single functions to
 be called at specific times, or a collection of alternative methods to try,
 callbacks are designed to be used by extension authors. A number of callbacks
 can be registered for the same event without needing to be aware of one another.
 
 The functions defined in this module are no-ops indicating the names of available
 events and the arguments which will be passed to them.
 
 .. note::
 
    This API is experimental in IPython 2.0, and may be revised in future versions.
 """
 
 from backcall import callback_prototype
 
 
 class EventManager(object):
     """Manage a collection of events and a sequence of callbacks for each.
     
     This is attached to :class:`~IPython.core.interactiveshell.InteractiveShell`
     instances as an ``events`` attribute.
     
     .. note::
 
        This API is experimental in IPython 2.0, and may be revised in future versions.
     """
     def __init__(self, shell, available_events):
         """Initialise the :class:`CallbackManager`.
-        
+
         Parameters
         ----------
         shell
-          The :class:`~IPython.core.interactiveshell.InteractiveShell` instance
-        available_callbacks
-          An iterable of names for callback events.
+            The :class:`~IPython.core.interactiveshell.InteractiveShell` instance
+        available_events
+            An iterable of names for callback events.
         """
         self.shell = shell
         self.callbacks = {n:[] for n in available_events}
     
     def register(self, event, function):
         """Register a new event callback.
-        
+
         Parameters
         ----------
         event : str
-          The event for which to register this callback.
+            The event for which to register this callback.
         function : callable
-          A function to be called on the given event. It should take the same
-          parameters as the appropriate callback prototype.
-        
+            A function to be called on the given event. It should take the same
+            parameters as the appropriate callback prototype.
+
         Raises
         ------
         TypeError
-          If ``function`` is not callable.
+            If ``function`` is not callable.
         KeyError
-          If ``event`` is not one of the known events.
+            If ``event`` is not one of the known events.
         """
         if not callable(function):
             raise TypeError('Need a callable, got %r' % function)
         callback_proto = available_events.get(event)
         if function not in self.callbacks[event]:
             self.callbacks[event].append(callback_proto.adapt(function))
     
     def unregister(self, event, function):
         """Remove a callback from the given event."""
         if function in self.callbacks[event]:
             return self.callbacks[event].remove(function)
 
         # Remove callback in case ``function`` was adapted by `backcall`.
         for callback in self.callbacks[event]:
             try:
                 if callback.__wrapped__ is function:
                     return self.callbacks[event].remove(callback)
             except AttributeError:
                 pass
 
         raise ValueError('Function {!r} is not registered as a {} callback'.format(function, event))
 
     def trigger(self, event, *args, **kwargs):
         """Call callbacks for ``event``.
-        
+
         Any additional arguments are passed to all callbacks registered for this
         event. Exceptions raised by callbacks are caught, and a message printed.
         """
         for func in self.callbacks[event][:]:
             try:
                 func(*args, **kwargs)
             except (Exception, KeyboardInterrupt):
                 print("Error in callback {} (for {}):".format(func, event))
                 self.shell.showtraceback()
 
 # event_name -> prototype mapping
 available_events = {}
 
 def _define_event(callback_function):
     callback_proto = callback_prototype(callback_function)
     available_events[callback_function.__name__] = callback_proto
     return callback_proto
 
 # ------------------------------------------------------------------------------
 # Callback prototypes
 #
 # No-op functions which describe the names of available events and the
 # signatures of callbacks for those events.
 # ------------------------------------------------------------------------------
 
 @_define_event
 def pre_execute():
     """Fires before code is executed in response to user/frontend action.
-    
+
     This includes comm and widget messages and silent execution, as well as user
     code cells.
     """
     pass
 
 @_define_event
 def pre_run_cell(info):
     """Fires before user-entered code runs.
 
     Parameters
     ----------
     info : :class:`~IPython.core.interactiveshell.ExecutionInfo`
-      An object containing information used for the code execution.
+        An object containing information used for the code execution.
     """
     pass
 
 @_define_event
 def post_execute():
     """Fires after code is executed in response to user/frontend action.
-    
+
     This includes comm and widget messages and silent execution, as well as user
     code cells.
     """
     pass
 
 @_define_event
 def post_run_cell(result):
     """Fires after user-entered code runs.
 
     Parameters
     ----------
     result : :class:`~IPython.core.interactiveshell.ExecutionResult`
-      The object which will be returned as the execution result.
+        The object which will be returned as the execution result.
     """
     pass
 
 @_define_event
 def shell_initialized(ip):
     """Fires after initialisation of :class:`~IPython.core.interactiveshell.InteractiveShell`.
-    
+
     This is before extensions and startup scripts are loaded, so it can only be
     set by subclassing.
-    
+
     Parameters
     ----------
     ip : :class:`~IPython.core.interactiveshell.InteractiveShell`
-      The newly initialised shell.
+        The newly initialised shell.
     """
     pass

IPython/core/extensions.py

@@ -1,150 +1,150 b''
 # encoding: utf-8
 """A class for managing IPython extensions."""
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import os
 import os.path
 import sys
 from importlib import import_module, reload
 
 from traitlets.config.configurable import Configurable
 from IPython.utils.path import ensure_dir_exists, compress_user
 from IPython.utils.decorators import undoc
 from traitlets import Instance
 
 
 #-----------------------------------------------------------------------------
 # Main class
 #-----------------------------------------------------------------------------
 
 class ExtensionManager(Configurable):
     """A class to manage IPython extensions.
 
     An IPython extension is an importable Python module that has
     a function with the signature::
 
         def load_ipython_extension(ipython):
             # Do things with ipython
 
     This function is called after your extension is imported and the
     currently active :class:`InteractiveShell` instance is passed as
     the only argument.  You can do anything you want with IPython at
     that point, including defining new magic and aliases, adding new
     components, etc.
     
     You can also optionally define an :func:`unload_ipython_extension(ipython)`
     function, which will be called if the user unloads or reloads the extension.
     The extension manager will only call :func:`load_ipython_extension` again
     if the extension is reloaded.
 
     You can put your extension modules anywhere you want, as long as
     they can be imported by Python's standard import mechanism.  However,
     to make it easy to write extensions, you can also put your extensions
     in ``os.path.join(self.ipython_dir, 'extensions')``.  This directory
     is added to ``sys.path`` automatically.
     """
 
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
 
     def __init__(self, shell=None, **kwargs):
         super(ExtensionManager, self).__init__(shell=shell, **kwargs)
         self.shell.observe(
             self._on_ipython_dir_changed, names=('ipython_dir',)
         )
         self.loaded = set()
 
     @property
     def ipython_extension_dir(self):
         return os.path.join(self.shell.ipython_dir, u'extensions')
 
     def _on_ipython_dir_changed(self, change):
         ensure_dir_exists(self.ipython_extension_dir)
 
     def load_extension(self, module_str):
         """Load an IPython extension by its module name.
 
         Returns the string "already loaded" if the extension is already loaded,
         "no load function" if the module doesn't have a load_ipython_extension
         function, or None if it succeeded.
         """
         if module_str in self.loaded:
             return "already loaded"
 
         from IPython.utils.syspathcontext import prepended_to_syspath
 
         with self.shell.builtin_trap:
             if module_str not in sys.modules:
                 with prepended_to_syspath(self.ipython_extension_dir):
                     mod = import_module(module_str)
                     if mod.__file__.startswith(self.ipython_extension_dir):
                         print(("Loading extensions from {dir} is deprecated. "
                                "We recommend managing extensions like any "
                                "other Python packages, in site-packages.").format(
                               dir=compress_user(self.ipython_extension_dir)))
             mod = sys.modules[module_str]
             if self._call_load_ipython_extension(mod):
                 self.loaded.add(module_str)
             else:
                 return "no load function"
 
     def unload_extension(self, module_str):
         """Unload an IPython extension by its module name.
 
         This function looks up the extension's name in ``sys.modules`` and
         simply calls ``mod.unload_ipython_extension(self)``.
-        
+
         Returns the string "no unload function" if the extension doesn't define
         a function to unload itself, "not loaded" if the extension isn't loaded,
         otherwise None.
         """
         if module_str not in self.loaded:
             return "not loaded"
         
         if module_str in sys.modules:
             mod = sys.modules[module_str]
             if self._call_unload_ipython_extension(mod):
                 self.loaded.discard(module_str)
             else:
                 return "no unload function"
 
     def reload_extension(self, module_str):
         """Reload an IPython extension by calling reload.
 
         If the module has not been loaded before,
         :meth:`InteractiveShell.load_extension` is called. Otherwise
         :func:`reload` is called and then the :func:`load_ipython_extension`
         function of the module, if it exists is called.
         """
         from IPython.utils.syspathcontext import prepended_to_syspath
 
         if (module_str in self.loaded) and (module_str in sys.modules):
             self.unload_extension(module_str)
             mod = sys.modules[module_str]
             with prepended_to_syspath(self.ipython_extension_dir):
                 reload(mod)
             if self._call_load_ipython_extension(mod):
                 self.loaded.add(module_str)
         else:
             self.load_extension(module_str)
 
     def _call_load_ipython_extension(self, mod):
         if hasattr(mod, 'load_ipython_extension'):
             mod.load_ipython_extension(self.shell)
             return True
 
     def _call_unload_ipython_extension(self, mod):
         if hasattr(mod, 'unload_ipython_extension'):
             mod.unload_ipython_extension(self.shell)
             return True
 
     @undoc
     def install_extension(self, url, filename=None):
         """
         Deprecated.
         """
         # Ensure the extension directory exists
         raise DeprecationWarning(
             '`install_extension` and the `install_ext` magic have been deprecated since IPython 4.0'
             'Use pip or other package managers to manage ipython extensions.')

IPython/core/formatters.py

@@ -1,1028 +1,1026 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 io import StringIO
 
 from decorator import decorator
 
 from traitlets.config.configurable import Configurable
 from .getipython import get_ipython
 from ..utils.sentinel import Sentinel
 from ..utils.dir2 import get_real_method
 from ..lib import pretty
 from traitlets import (
     Bool, Dict, Integer, Unicode, CUnicode, ObjectName, List,
     ForwardDeclaredInstance,
     default, observe,
 )
 
 
 class DisplayFormatter(Configurable):
 
     active_types = List(Unicode(),
         help="""List of currently active mime-types to display.
         You can use this to set a white-list for formats to display.
         
         Most users will not need to change this value.
         """).tag(config=True)
 
     @default('active_types')
     def _active_types_default(self):
         return self.format_types
 
     @observe('active_types')
     def _active_types_changed(self, change):
         for key, formatter in self.formatters.items():
             if key in change['new']:
                 formatter.enabled = True
             else:
                 formatter.enabled = False
 
     ipython_display_formatter = ForwardDeclaredInstance('FormatterABC')
     @default('ipython_display_formatter')
     def _default_formatter(self):
         return IPythonDisplayFormatter(parent=self)
 
     mimebundle_formatter = ForwardDeclaredInstance('FormatterABC')
     @default('mimebundle_formatter')
     def _default_mime_formatter(self):
         return MimeBundleFormatter(parent=self)
 
     # A dict of formatter whose keys are format types (MIME types) and whose
     # values are subclasses of BaseFormatter.
     formatters = Dict()
     @default('formatters')
     def _formatters_default(self):
         """Activate the default formatters."""
         formatter_classes = [
             PlainTextFormatter,
             HTMLFormatter,
             MarkdownFormatter,
             SVGFormatter,
             PNGFormatter,
             PDFFormatter,
             JPEGFormatter,
             LatexFormatter,
             JSONFormatter,
             JavascriptFormatter
         ]
         d = {}
         for cls in formatter_classes:
             f = cls(parent=self)
             d[f.format_type] = f
         return d
 
     def format(self, obj, include=None, exclude=None):
         """Return a format data dict for an object.
 
         By default all format types will be computed.
 
         The following MIME types are usually implemented:
 
         * text/plain
         * text/html
         * text/markdown
         * text/latex
         * application/json
         * application/javascript
         * application/pdf
         * image/png
         * image/jpeg
         * image/svg+xml
 
         Parameters
         ----------
         obj : object
             The Python object whose format data will be computed.
         include : list, tuple or set; optional
             A list of format type strings (MIME types) to include in the
             format data dict. If this is set *only* the format types included
             in this list will be computed.
         exclude : list, tuple or set; optional
             A list of format type string (MIME types) to exclude in the format
             data dict. If this is set all format types will be computed,
             except for those included in this argument.
             Mimetypes present in exclude will take precedence over the ones in include
 
         Returns
         -------
         (format_dict, metadata_dict) : tuple of two dicts
-        
             format_dict is a dictionary of key/value pairs, one of each format that was
             generated for the object. The keys are the format types, which
             will usually be MIME type strings and the values and JSON'able
             data structure containing the raw data for the representation in
             that format.
-            
+
             metadata_dict is a dictionary of metadata about each mime-type output.
             Its keys will be a strict subset of the keys in format_dict.
 
         Notes
         -----
-
             If an object implement `_repr_mimebundle_` as well as various
             `_repr_*_`, the data returned by `_repr_mimebundle_` will take
             precedence and the corresponding `_repr_*_` for this mimetype will
             not be called.
 
         """
         format_dict = {}
         md_dict = {}
         
         if self.ipython_display_formatter(obj):
             # object handled itself, don't proceed
             return {}, {}
 
         format_dict, md_dict = self.mimebundle_formatter(obj, include=include, exclude=exclude)
 
         if format_dict or md_dict:
             if include:
                 format_dict = {k:v for k,v in format_dict.items() if k in include}
                 md_dict = {k:v for k,v in md_dict.items() if k in include}
             if exclude:
                 format_dict = {k:v for k,v in format_dict.items() if k not in exclude}
                 md_dict = {k:v for k,v in md_dict.items() if k not in exclude}
 
         for format_type, formatter in self.formatters.items():
             if format_type in format_dict:
                 # already got it from mimebundle, maybe don't render again.
                 # exception: manually registered per-mime renderer
                 # check priority:
                 # 1. user-registered per-mime formatter
                 # 2. mime-bundle (user-registered or repr method)
                 # 3. default per-mime formatter (e.g. repr method)
                 try:
                     formatter.lookup(obj)
                 except KeyError:
                     # no special formatter, use mime-bundle-provided value
                     continue
             if include and format_type not in include:
                 continue
             if exclude and format_type in exclude:
                 continue
             
             md = None
             try:
                 data = formatter(obj)
             except:
                 # FIXME: log the exception
                 raise
             
             # formatters can return raw data or (data, metadata)
             if isinstance(data, tuple) and len(data) == 2:
                 data, md = data
             
             if data is not None:
                 format_dict[format_type] = data
             if md is not None:
                 md_dict[format_type] = md
         return format_dict, md_dict
 
     @property
     def format_types(self):
         """Return the format types (MIME types) of the active formatters."""
         return list(self.formatters.keys())
 
 
 #-----------------------------------------------------------------------------
 # Formatters for specific format types (text, html, svg, etc.)
 #-----------------------------------------------------------------------------
 
 
 def _safe_repr(obj):
     """Try to return a repr of an object
 
     always returns a string, at least.
     """
     try:
         return repr(obj)
     except Exception as e:
         return "un-repr-able object (%r)" % e
 
 
 class FormatterWarning(UserWarning):
     """Warning class for errors in formatters"""
 
 @decorator
 def catch_format_error(method, self, *args, **kwargs):
     """show traceback on failed format call"""
     try:
         r = method(self, *args, **kwargs)
     except NotImplementedError:
         # don't warn on NotImplementedErrors
         return self._check_return(None, args[0])
     except Exception:
         exc_info = sys.exc_info()
         ip = get_ipython()
         if ip is not None:
             ip.showtraceback(exc_info)
         else:
             traceback.print_exception(*exc_info)
         return self._check_return(None, args[0])
     return self._check_return(r, args[0])
 
 
 class FormatterABC(metaclass=abc.ABCMeta):
     """ Abstract base class for Formatters.
 
     A formatter is a callable class that is responsible for computing the
     raw format data for a particular format type (MIME type). For example,
     an HTML formatter would have a format type of `text/html` and would return
     the HTML representation of the object when called.
     """
 
     # The format type of the data returned, usually a MIME type.
     format_type = 'text/plain'
 
     # Is the formatter enabled...
     enabled = True
     
     @abc.abstractmethod
     def __call__(self, obj):
         """Return a JSON'able representation of the object.
 
         If the object cannot be formatted by this formatter,
         warn and return None.
         """
         return repr(obj)
 
 
 def _mod_name_key(typ):
     """Return a (__module__, __name__) tuple for a type.
-    
+
     Used as key in Formatter.deferred_printers.
     """
     module = getattr(typ, '__module__', None)
     name = getattr(typ, '__name__', None)
     return (module, name)
 
 
 def _get_type(obj):
     """Return the type of an instance (old and new-style)"""
     return getattr(obj, '__class__', None) or type(obj)
 
 
 _raise_key_error = Sentinel('_raise_key_error', __name__, 
 """
 Special value to raise a KeyError
 
 Raise KeyError in `BaseFormatter.pop` if passed as the default value to `pop`
 """)
 
 
 class BaseFormatter(Configurable):
     """A base formatter class that is configurable.
 
     This formatter should usually be used as the base class of all formatters.
     It is a traited :class:`Configurable` class and includes an extensible
     API for users to determine how their objects are formatted. The following
     logic is used to find a function to format an given object.
 
     1. The object is introspected to see if it has a method with the name
        :attr:`print_method`. If is does, that object is passed to that method
        for formatting.
     2. If no print method is found, three internal dictionaries are consulted
        to find print method: :attr:`singleton_printers`, :attr:`type_printers`
        and :attr:`deferred_printers`.
 
     Users should use these dictionaries to register functions that will be
     used to compute the format data for their objects (if those objects don't
     have the special print methods). The easiest way of using these
     dictionaries is through the :meth:`for_type` and :meth:`for_type_by_name`
     methods.
 
     If no function/callable is found to compute the format data, ``None`` is
     returned and this format type is not used.
     """
 
     format_type = Unicode('text/plain')
     _return_type = str
 
     enabled = Bool(True).tag(config=True)
 
     print_method = ObjectName('__repr__')
 
     # The singleton printers.
     # Maps the IDs of the builtin singleton objects to the format functions.
     singleton_printers = Dict().tag(config=True)
 
     # The type-specific printers.
     # Map type objects to the format functions.
     type_printers = Dict().tag(config=True)
 
     # The deferred-import type-specific printers.
     # Map (modulename, classname) pairs to the format functions.
     deferred_printers = Dict().tag(config=True)
     
     @catch_format_error
     def __call__(self, obj):
         """Compute the format for an object."""
         if self.enabled:
             # lookup registered printer
             try:
                 printer = self.lookup(obj)
             except KeyError:
                 pass
             else:
                 return printer(obj)
             # Finally look for special method names
             method = get_real_method(obj, self.print_method)
             if method is not None:
                 return method()
             return None
         else:
             return None
     
     def __contains__(self, typ):
         """map in to lookup_by_type"""
         try:
             self.lookup_by_type(typ)
         except KeyError:
             return False
         else:
             return True
     
     def _check_return(self, r, obj):
         """Check that a return value is appropriate
-        
+
         Return the value if so, None otherwise, warning if invalid.
         """
         if r is None or isinstance(r, self._return_type) or \
             (isinstance(r, tuple) and r and isinstance(r[0], self._return_type)):
             return r
         else:
             warnings.warn(
                 "%s formatter returned invalid type %s (expected %s) for object: %s" % \
                 (self.format_type, type(r), self._return_type, _safe_repr(obj)),
                 FormatterWarning
             )
     
     def lookup(self, obj):
         """Look up the formatter for a given instance.
-        
+
         Parameters
         ----------
-        obj  : object instance
+        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
+        typ : type or '__module__.__name__' string for a type
 
         Returns
         -------
         f : callable
             The registered formatting callable for the type.
 
         Raises
         ------
         KeyError if the type has not been registered.
         """
         if isinstance(typ, str):
             typ_key = tuple(typ.rsplit('.',1))
             if typ_key not in self.deferred_printers:
                 # We may have it cached in the type map. We will have to
                 # iterate over all of the types to check.
                 for cls in self.type_printers:
                     if _mod_name_key(cls) == typ_key:
                         return self.type_printers[cls]
             else:
                 return self.deferred_printers[typ_key]
         else:
             for cls in pretty._get_mro(typ):
                 if cls in self.type_printers or self._in_deferred_types(cls):
                     return self.type_printers[cls]
         
         # If we have reached here, the lookup failed.
         raise KeyError("No registered printer for {0!r}".format(typ))
 
     def for_type(self, typ, func=None):
         """Add a format function for a given type.
-        
+
         Parameters
         ----------
         typ : type or '__module__.__name__' string for a type
             The class of the object that will be formatted using `func`.
         func : callable
             A callable for computing the format data.
             `func` will be called with the object to be formatted,
             and will return the raw data in this formatter's format.
             Subclasses may use a different call signature for the
             `func` argument.
-            
+
             If `func` is None or not specified, there will be no change,
             only returning the current value.
-        
+
         Returns
         -------
         oldfunc : callable
             The currently registered callable.
             If you are registering a new formatter,
             this will be the previous value (to enable restoring later).
         """
         # if string given, interpret as 'pkg.module.class_name'
         if isinstance(typ, str):
             type_module, type_name = typ.rsplit('.', 1)
             return self.for_type_by_name(type_module, type_name, func)
         
         try:
             oldfunc = self.lookup_by_type(typ)
         except KeyError:
             oldfunc = None
         
         if func is not None:
             self.type_printers[typ] = func
         
         return oldfunc
 
     def for_type_by_name(self, type_module, type_name, func=None):
         """Add a format function for a type specified by the full dotted
         module and name of the type, rather than the type of the object.
 
         Parameters
         ----------
         type_module : str
             The full dotted name of the module the type is defined in, like
             ``numpy``.
         type_name : str
             The name of the type (the class name), like ``dtype``
         func : callable
             A callable for computing the format data.
             `func` will be called with the object to be formatted,
             and will return the raw data in this formatter's format.
             Subclasses may use a different call signature for the
             `func` argument.
-            
+
             If `func` is None or unspecified, there will be no change,
             only returning the current value.
-        
+
         Returns
         -------
         oldfunc : callable
             The currently registered callable.
             If you are registering a new formatter,
             this will be the previous value (to enable restoring later).
         """
         key = (type_module, type_name)
         
         try:
             oldfunc = self.lookup_by_type("%s.%s" % key)
         except KeyError:
             oldfunc = None
         
         if func is not None:
             self.deferred_printers[key] = func
         return oldfunc
     
     def pop(self, typ, default=_raise_key_error):
         """Pop a formatter for the given type.
 
         Parameters
         ----------
         typ : type or '__module__.__name__' string for a type
         default : object
             value to be returned if no formatter is registered for typ.
 
         Returns
         -------
         obj : object
             The last registered object for the type.
 
         Raises
         ------
         KeyError if the type is not registered and default is not specified.
         """
         
         if isinstance(typ, str):
             typ_key = tuple(typ.rsplit('.',1))
             if typ_key not in self.deferred_printers:
                 # We may have it cached in the type map. We will have to
                 # iterate over all of the types to check.
                 for cls in self.type_printers:
                     if _mod_name_key(cls) == typ_key:
                         old = self.type_printers.pop(cls)
                         break
                 else:
                     old = default
             else:
                 old = self.deferred_printers.pop(typ_key)
         else:
             if typ in self.type_printers:
                 old = self.type_printers.pop(typ)
             else:
                 old = self.deferred_printers.pop(_mod_name_key(typ), default)
         if old is _raise_key_error:
             raise KeyError("No registered value for {0!r}".format(typ))
         return old
 
     def _in_deferred_types(self, cls):
         """
         Check if the given class is specified in the deferred type registry.
 
         Successful matches will be moved to the regular type registry for future use.
         """
         mod = getattr(cls, '__module__', None)
         name = getattr(cls, '__name__', None)
         key = (mod, name)
         if key in self.deferred_printers:
             # Move the printer over to the regular registry.
             printer = self.deferred_printers.pop(key)
             self.type_printers[cls] = printer
             return True
         return False
 
 
 class PlainTextFormatter(BaseFormatter):
     """The default pretty-printer.
 
     This uses :mod:`IPython.lib.pretty` to compute the format data of
     the object. If the object cannot be pretty printed, :func:`repr` is used.
     See the documentation of :mod:`IPython.lib.pretty` for details on
     how to write pretty printers.  Here is a simple example::
 
         def dtype_pprinter(obj, p, cycle):
             if cycle:
                 return p.text('dtype(...)')
             if hasattr(obj, 'fields'):
                 if obj.fields is None:
                     p.text(repr(obj))
                 else:
                     p.begin_group(7, 'dtype([')
                     for i, field in enumerate(obj.descr):
                         if i > 0:
                             p.text(',')
                             p.breakable()
                         p.pretty(field)
                     p.end_group(7, '])')
     """
 
     # The format type of data returned.
     format_type = Unicode('text/plain')
 
     # This subclass ignores this attribute as it always need to return
     # something.
     enabled = Bool(True).tag(config=False)
     
     max_seq_length = Integer(pretty.MAX_SEQ_LENGTH,
         help="""Truncate large collections (lists, dicts, tuples, sets) to this size.
         
         Set to 0 to disable truncation.
         """
     ).tag(config=True)
     
     # Look for a _repr_pretty_ methods to use for pretty printing.
     print_method = ObjectName('_repr_pretty_')
 
     # Whether to pretty-print or not.
     pprint = Bool(True).tag(config=True)
 
     # Whether to be verbose or not.
     verbose = Bool(False).tag(config=True)
 
     # The maximum width.
     max_width = Integer(79).tag(config=True)
 
     # The newline character.
     newline = Unicode('\n').tag(config=True)
 
     # format-string for pprinting floats
     float_format = Unicode('%r')
     # setter for float precision, either int or direct format-string
     float_precision = CUnicode('').tag(config=True)
 
     @observe('float_precision')
     def _float_precision_changed(self, change):
         """float_precision changed, set float_format accordingly.
 
         float_precision can be set by int or str.
         This will set float_format, after interpreting input.
         If numpy has been imported, numpy print precision will also be set.
 
         integer `n` sets format to '%.nf', otherwise, format set directly.
 
         An empty string returns to defaults (repr for float, 8 for numpy).
 
         This parameter can be set via the '%precision' magic.
         """
         new = change['new']
         if '%' in new:
             # got explicit format string
             fmt = new
             try:
                 fmt%3.14159
             except Exception as e:
                 raise ValueError("Precision must be int or format string, not %r"%new) from e
         elif new:
             # otherwise, should be an int
             try:
                 i = int(new)
                 assert i >= 0
             except ValueError as e:
                 raise ValueError("Precision must be int or format string, not %r"%new) from e
             except AssertionError as e:
                 raise ValueError("int precision must be non-negative, not %r"%i) from e
 
             fmt = '%%.%if'%i
             if 'numpy' in sys.modules:
                 # set numpy precision if it has been imported
                 import numpy
                 numpy.set_printoptions(precision=i)
         else:
             # default back to repr
             fmt = '%r'
             if 'numpy' in sys.modules:
                 import numpy
                 # numpy default is 8
                 numpy.set_printoptions(precision=8)
         self.float_format = fmt
 
     # Use the default pretty printers from IPython.lib.pretty.
     @default('singleton_printers')
     def _singleton_printers_default(self):
         return pretty._singleton_pprinters.copy()
 
     @default('type_printers')
     def _type_printers_default(self):
         d = pretty._type_pprinters.copy()
         d[float] = lambda obj,p,cycle: p.text(self.float_format%obj)
         # if NumPy is used, set precision for its float64 type
         if "numpy" in sys.modules:
             import numpy
 
             d[numpy.float64] = lambda obj, p, cycle: p.text(self.float_format % obj)
         return d
 
     @default('deferred_printers')
     def _deferred_printers_default(self):
         return pretty._deferred_type_pprinters.copy()
 
     #### FormatterABC interface ####
 
     @catch_format_error
     def __call__(self, obj):
         """Compute the pretty representation of the object."""
         if not self.pprint:
             return repr(obj)
         else:
             stream = StringIO()
             printer = pretty.RepresentationPrinter(stream, self.verbose,
                 self.max_width, self.newline,
                 max_seq_length=self.max_seq_length,
                 singleton_pprinters=self.singleton_printers,
                 type_pprinters=self.type_printers,
                 deferred_pprinters=self.deferred_printers)
             printer.pretty(obj)
             printer.flush()
             return stream.getvalue()
 
 
 class HTMLFormatter(BaseFormatter):
     """An HTML formatter.
 
     To define the callables that compute the HTML representation of your
     objects, define a :meth:`_repr_html_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a valid HTML snippet that
     could be injected into an existing DOM. It should *not* include the
     ```<html>`` or ```<body>`` tags.
     """
     format_type = Unicode('text/html')
 
     print_method = ObjectName('_repr_html_')
 
 
 class MarkdownFormatter(BaseFormatter):
     """A Markdown formatter.
 
     To define the callables that compute the Markdown representation of your
     objects, define a :meth:`_repr_markdown_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a valid Markdown.
     """
     format_type = Unicode('text/markdown')
 
     print_method = ObjectName('_repr_markdown_')
 
 class SVGFormatter(BaseFormatter):
     """An SVG formatter.
 
     To define the callables that compute the SVG representation of your
     objects, define a :meth:`_repr_svg_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be valid SVG enclosed in
     ```<svg>``` tags, that could be injected into an existing DOM. It should
     *not* include the ```<html>`` or ```<body>`` tags.
     """
     format_type = Unicode('image/svg+xml')
 
     print_method = ObjectName('_repr_svg_')
 
 
 class PNGFormatter(BaseFormatter):
     """A PNG formatter.
 
     To define the callables that compute the PNG representation of your
     objects, define a :meth:`_repr_png_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be raw PNG data, *not*
     base64 encoded.
     """
     format_type = Unicode('image/png')
 
     print_method = ObjectName('_repr_png_')
     
     _return_type = (bytes, str)
 
 
 class JPEGFormatter(BaseFormatter):
     """A JPEG formatter.
 
     To define the callables that compute the JPEG representation of your
     objects, define a :meth:`_repr_jpeg_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be raw JPEG data, *not*
     base64 encoded.
     """
     format_type = Unicode('image/jpeg')
 
     print_method = ObjectName('_repr_jpeg_')
 
     _return_type = (bytes, str)
 
 
 class LatexFormatter(BaseFormatter):
     """A LaTeX formatter.
 
     To define the callables that compute the LaTeX representation of your
     objects, define a :meth:`_repr_latex_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a valid LaTeX equation,
     enclosed in either ```$```, ```$$``` or another LaTeX equation
     environment.
     """
     format_type = Unicode('text/latex')
 
     print_method = ObjectName('_repr_latex_')
 
 
 class JSONFormatter(BaseFormatter):
     """A JSON string formatter.
 
     To define the callables that compute the JSONable representation of
     your objects, define a :meth:`_repr_json_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     The return value of this formatter should be a JSONable list or dict.
     JSON scalars (None, number, string) are not allowed, only dict or list containers.
     """
     format_type = Unicode('application/json')
     _return_type = (list, dict)
 
     print_method = ObjectName('_repr_json_')
     
     def _check_return(self, r, obj):
         """Check that a return value is appropriate
-        
+
         Return the value if so, None otherwise, warning if invalid.
         """
         if r is None:
             return
         md = None
         if isinstance(r, tuple):
             # unpack data, metadata tuple for type checking on first element
             r, md = r
         
         # handle deprecated JSON-as-string form from IPython < 3
         if isinstance(r, str):
             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, str)
 
 class IPythonDisplayFormatter(BaseFormatter):
     """An escape-hatch Formatter for objects that know how to display themselves.
     
     To define the callables that compute the representation of your
     objects, define a :meth:`_ipython_display_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this. Unlike mime-type displays, this method should not return anything,
     instead calling any appropriate display methods itself.
     
     This display formatter has highest priority.
     If it fires, no other display formatter will be called.
 
     Prior to IPython 6.1, `_ipython_display_` was the only way to display custom mime-types
     without registering a new Formatter.
     
     IPython 6.1 introduces `_repr_mimebundle_` for displaying custom mime-types,
     so `_ipython_display_` should only be used for objects that require unusual
     display patterns, such as multiple display calls.
     """
     print_method = ObjectName('_ipython_display_')
     _return_type = (type(None), bool)
 
     @catch_format_error
     def __call__(self, obj):
         """Compute the format for an object."""
         if self.enabled:
             # lookup registered printer
             try:
                 printer = self.lookup(obj)
             except KeyError:
                 pass
             else:
                 printer(obj)
                 return True
             # Finally look for special method names
             method = get_real_method(obj, self.print_method)
             if method is not None:
                 method()
                 return True
 
 
 class MimeBundleFormatter(BaseFormatter):
     """A Formatter for arbitrary mime-types.
 
     Unlike other `_repr_<mimetype>_` methods,
     `_repr_mimebundle_` should return mime-bundle data,
     either the mime-keyed `data` dictionary or the tuple `(data, metadata)`.
     Any mime-type is valid.
 
     To define the callables that compute the mime-bundle representation of your
     objects, define a :meth:`_repr_mimebundle_` method or use the :meth:`for_type`
     or :meth:`for_type_by_name` methods to register functions that handle
     this.
 
     .. versionadded:: 6.1
     """
     print_method = ObjectName('_repr_mimebundle_')
     _return_type = dict
     
     def _check_return(self, r, obj):
         r = super(MimeBundleFormatter, self)._check_return(r, obj)
         # always return (data, metadata):
         if r is None:
             return {}, {}
         if not isinstance(r, tuple):
             return r, {}
         return r
 
     @catch_format_error
     def __call__(self, obj, include=None, exclude=None):
         """Compute the format for an object.
 
         Identical to parent's method but we pass extra parameters to the method.
 
         Unlike other _repr_*_ `_repr_mimebundle_` should allow extra kwargs, in
         particular `include` and `exclude`.
         """
         if self.enabled:
             # lookup registered printer
             try:
                 printer = self.lookup(obj)
             except KeyError:
                 pass
             else:
                 return printer(obj)
             # Finally look for special method names
             method = get_real_method(obj, self.print_method)
 
             if method is not None:
                 return method(include=include, exclude=exclude)
             return None
         else:
             return None
 
 
 FormatterABC.register(BaseFormatter)
 FormatterABC.register(PlainTextFormatter)
 FormatterABC.register(HTMLFormatter)
 FormatterABC.register(MarkdownFormatter)
 FormatterABC.register(SVGFormatter)
 FormatterABC.register(PNGFormatter)
 FormatterABC.register(PDFFormatter)
 FormatterABC.register(JPEGFormatter)
 FormatterABC.register(LatexFormatter)
 FormatterABC.register(JSONFormatter)
 FormatterABC.register(JavascriptFormatter)
 FormatterABC.register(IPythonDisplayFormatter)
 FormatterABC.register(MimeBundleFormatter)
 
 
 def format_display_data(obj, include=None, exclude=None):
     """Return a format data dict for an object.
 
     By default all format types will be computed.
 
     Parameters
     ----------
     obj : object
         The Python object whose format data will be computed.
 
     Returns
     -------
     format_dict : dict
         A dictionary of key/value pairs, one or each format that was
         generated for the object. The keys are the format types, which
         will usually be MIME type strings and the values and JSON'able
         data structure containing the raw data for the representation in
         that format.
     include : list or tuple, optional
         A list of format type strings (MIME types) to include in the
         format data dict. If this is set *only* the format types included
         in this list will be computed.
     exclude : list or tuple, optional
         A list of format type string (MIME types) to exclude in the format
         data dict. If this is set all format types will be computed,
         except for those included in this argument.
     """
     from .interactiveshell import InteractiveShell
 
     return InteractiveShell.instance().display_formatter.format(
         obj,
         include,
         exclude
     )

setup.cfg

@@ -1,2 +1,7 b''
 [metadata]
 license_file = LICENSE
+
+[velin]
+ignore_patterns = 
+   IPython/core/tests,
+   IPython/testing