##// END OF EJS Templates
Make post-execution happen at the cell instead of the block level....
Make post-execution happen at the cell instead of the block level. This was the original intent of the design, and it's necessary if we want post-execute functions to be used to pick up things like figures at the end of an entire cell, rather than multiple times per cell (which defeats the purpose of the whole design).

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ipython_widget.py
490 lines | 20.3 KiB | text/x-python | PythonLexer
""" A FrontendWidget that emulates the interface of the console IPython and
supports the additional functionality provided by the IPython kernel.
"""
#-----------------------------------------------------------------------------
# Imports
#-----------------------------------------------------------------------------
# Standard library imports
from collections import namedtuple
import re
from subprocess import Popen
from textwrap import dedent
# System library imports
from IPython.external.qt import QtCore, QtGui
# Local imports
from IPython.core.inputsplitter import IPythonInputSplitter, \
transform_ipy_prompt
from IPython.core.usage import default_gui_banner
from IPython.utils.traitlets import Bool, Str, Unicode
from frontend_widget import FrontendWidget
from styles import (default_light_style_sheet, default_light_syntax_style,
default_dark_style_sheet, default_dark_syntax_style,
default_bw_style_sheet, default_bw_syntax_style)
#-----------------------------------------------------------------------------
# Constants
#-----------------------------------------------------------------------------
# Default strings to build and display input and output prompts (and separators
# in between)
default_in_prompt = 'In [<span class="in-prompt-number">%i</span>]: '
default_out_prompt = 'Out[<span class="out-prompt-number">%i</span>]: '
default_input_sep = '\n'
default_output_sep = ''
default_output_sep2 = ''
# Base path for most payload sources.
zmq_shell_source = 'IPython.zmq.zmqshell.ZMQInteractiveShell'
#-----------------------------------------------------------------------------
# IPythonWidget class
#-----------------------------------------------------------------------------
class IPythonWidget(FrontendWidget):
""" A FrontendWidget for an IPython kernel.
"""
# If set, the 'custom_edit_requested(str, int)' signal will be emitted when
# an editor is needed for a file. This overrides 'editor' and 'editor_line'
# settings.
custom_edit = Bool(False)
custom_edit_requested = QtCore.Signal(object, object)
# A command for invoking a system text editor. If the string contains a
# {filename} format specifier, it will be used. Otherwise, the filename will
# be appended to the end the command.
editor = Unicode('default', config=True)
# The editor command to use when a specific line number is requested. The
# string should contain two format specifiers: {line} and {filename}. If
# this parameter is not specified, the line number option to the %edit magic
# will be ignored.
editor_line = Unicode(config=True)
# A CSS stylesheet. The stylesheet can contain classes for:
# 1. Qt: QPlainTextEdit, QFrame, QWidget, etc
# 2. Pygments: .c, .k, .o, etc (see PygmentsHighlighter)
# 3. IPython: .error, .in-prompt, .out-prompt, etc
style_sheet = Unicode(config=True)
# If not empty, use this Pygments style for syntax highlighting. Otherwise,
# the style sheet is queried for Pygments style information.
syntax_style = Str(config=True)
# Prompts.
in_prompt = Str(default_in_prompt, config=True)
out_prompt = Str(default_out_prompt, config=True)
input_sep = Str(default_input_sep, config=True)
output_sep = Str(default_output_sep, config=True)
output_sep2 = Str(default_output_sep2, config=True)
# FrontendWidget protected class variables.
_input_splitter_class = IPythonInputSplitter
# IPythonWidget protected class variables.
_PromptBlock = namedtuple('_PromptBlock', ['block', 'length', 'number'])
_payload_source_edit = zmq_shell_source + '.edit_magic'
_payload_source_exit = zmq_shell_source + '.ask_exit'
_payload_source_loadpy = zmq_shell_source + '.magic_loadpy'
_payload_source_page = 'IPython.zmq.page.page'
#---------------------------------------------------------------------------
# 'object' interface
#---------------------------------------------------------------------------
def __init__(self, *args, **kw):
super(IPythonWidget, self).__init__(*args, **kw)
# IPythonWidget protected variables.
self._code_to_load = None
self._payload_handlers = {
self._payload_source_edit : self._handle_payload_edit,
self._payload_source_exit : self._handle_payload_exit,
self._payload_source_page : self._handle_payload_page,
self._payload_source_loadpy : self._handle_payload_loadpy }
self._previous_prompt_obj = None
self._keep_kernel_on_exit = None
# Initialize widget styling.
if self.style_sheet:
self._style_sheet_changed()
self._syntax_style_changed()
else:
self.set_default_style()
#---------------------------------------------------------------------------
# 'BaseFrontendMixin' abstract interface
#---------------------------------------------------------------------------
def _handle_complete_reply(self, rep):
""" Reimplemented to support IPython's improved completion machinery.
"""
cursor = self._get_cursor()
info = self._request_info.get('complete')
if info and info.id == rep['parent_header']['msg_id'] and \
info.pos == cursor.position():
matches = rep['content']['matches']
text = rep['content']['matched_text']
offset = len(text)
# Clean up matches with period and path separators if the matched
# text has not been transformed. This is done by truncating all
# but the last component and then suitably decreasing the offset
# between the current cursor position and the start of completion.
if len(matches) > 1 and matches[0][:offset] == text:
parts = re.split(r'[./\\]', text)
sep_count = len(parts) - 1
if sep_count:
chop_length = sum(map(len, parts[:sep_count])) + sep_count
matches = [ match[chop_length:] for match in matches ]
offset -= chop_length
# Move the cursor to the start of the match and complete.
cursor.movePosition(QtGui.QTextCursor.Left, n=offset)
self._complete_with_items(cursor, matches)
def _handle_execute_reply(self, msg):
""" Reimplemented to support prompt requests.
"""
info = self._request_info.get('execute')
if info and info.id == msg['parent_header']['msg_id']:
if info.kind == 'prompt':
number = msg['content']['execution_count'] + 1
self._show_interpreter_prompt(number)
else:
super(IPythonWidget, self)._handle_execute_reply(msg)
def _handle_history_tail_reply(self, msg):
""" Implemented to handle history tail replies, which are only supported
by the IPython kernel.
"""
history_items = msg['content']['history']
items = [ line.rstrip() for _, _, line in history_items ]
self._set_history(items)
def _handle_pyout(self, msg):
""" Reimplemented for IPython-style "display hook".
"""
if not self._hidden and self._is_from_this_session(msg):
content = msg['content']
prompt_number = content['execution_count']
data = content['data']
if data.has_key('text/html'):
self._append_plain_text(self.output_sep)
self._append_html(self._make_out_prompt(prompt_number))
html = data['text/html']
self._append_plain_text('\n')
self._append_html(html + self.output_sep2)
elif data.has_key('text/plain'):
self._append_plain_text(self.output_sep)
self._append_html(self._make_out_prompt(prompt_number))
text = data['text/plain']
self._append_plain_text(text + self.output_sep2)
def _handle_display_data(self, msg):
""" The base handler for the ``display_data`` message.
"""
# For now, we don't display data from other frontends, but we
# eventually will as this allows all frontends to monitor the display
# data. But we need to figure out how to handle this in the GUI.
if not self._hidden and self._is_from_this_session(msg):
source = msg['content']['source']
data = msg['content']['data']
metadata = msg['content']['metadata']
# In the regular IPythonWidget, we simply print the plain text
# representation.
if data.has_key('text/html'):
html = data['text/html']
self._append_html(html)
elif data.has_key('text/plain'):
text = data['text/plain']
self._append_plain_text(text)
# This newline seems to be needed for text and html output.
self._append_plain_text(u'\n')
def _started_channels(self):
""" Reimplemented to make a history request.
"""
super(IPythonWidget, self)._started_channels()
self.kernel_manager.xreq_channel.history_tail(1000)
#---------------------------------------------------------------------------
# 'ConsoleWidget' public interface
#---------------------------------------------------------------------------
def copy(self):
""" Copy the currently selected text to the clipboard, removing prompts
if possible.
"""
text = self._control.textCursor().selection().toPlainText()
if text:
lines = map(transform_ipy_prompt, text.splitlines())
text = '\n'.join(lines)
QtGui.QApplication.clipboard().setText(text)
#---------------------------------------------------------------------------
# 'FrontendWidget' public interface
#---------------------------------------------------------------------------
def execute_file(self, path, hidden=False):
""" Reimplemented to use the 'run' magic.
"""
self.execute('%%run %s' % path, hidden=hidden)
#---------------------------------------------------------------------------
# 'FrontendWidget' protected interface
#---------------------------------------------------------------------------
def _complete(self):
""" Reimplemented to support IPython's improved completion machinery.
"""
# We let the kernel split the input line, so we *always* send an empty
# text field. Readline-based frontends do get a real text field which
# they can use.
text = ''
# Send the completion request to the kernel
msg_id = self.kernel_manager.xreq_channel.complete(
text, # text
self._get_input_buffer_cursor_line(), # line
self._get_input_buffer_cursor_column(), # cursor_pos
self.input_buffer) # block
pos = self._get_cursor().position()
info = self._CompletionRequest(msg_id, pos)
self._request_info['complete'] = info
def _get_banner(self):
""" Reimplemented to return IPython's default banner.
"""
return default_gui_banner
def _process_execute_error(self, msg):
""" Reimplemented for IPython-style traceback formatting.
"""
content = msg['content']
traceback = '\n'.join(content['traceback']) + '\n'
if False:
# FIXME: For now, tracebacks come as plain text, so we can't use
# the html renderer yet. Once we refactor ultratb to produce
# properly styled tracebacks, this branch should be the default
traceback = traceback.replace(' ', '&nbsp;')
traceback = traceback.replace('\n', '<br/>')
ename = content['ename']
ename_styled = '<span class="error">%s</span>' % ename
traceback = traceback.replace(ename, ename_styled)
self._append_html(traceback)
else:
# This is the fallback for now, using plain text with ansi escapes
self._append_plain_text(traceback)
def _process_execute_payload(self, item):
""" Reimplemented to dispatch payloads to handler methods.
"""
handler = self._payload_handlers.get(item['source'])
if handler is None:
# We have no handler for this type of payload, simply ignore it
return False
else:
handler(item)
return True
def _show_interpreter_prompt(self, number=None):
""" Reimplemented for IPython-style prompts.
"""
# If a number was not specified, make a prompt number request.
if number is None:
msg_id = self.kernel_manager.xreq_channel.execute('', silent=True)
info = self._ExecutionRequest(msg_id, 'prompt')
self._request_info['execute'] = info
return
# Show a new prompt and save information about it so that it can be
# updated later if the prompt number turns out to be wrong.
self._prompt_sep = self.input_sep
self._show_prompt(self._make_in_prompt(number), html=True)
block = self._control.document().lastBlock()
length = len(self._prompt)
self._previous_prompt_obj = self._PromptBlock(block, length, number)
# Update continuation prompt to reflect (possibly) new prompt length.
self._set_continuation_prompt(
self._make_continuation_prompt(self._prompt), html=True)
# Load code from the %loadpy magic, if necessary.
if self._code_to_load is not None:
self.input_buffer = dedent(self._code_to_load.rstrip())
self._code_to_load = None
def _show_interpreter_prompt_for_reply(self, msg):
""" Reimplemented for IPython-style prompts.
"""
# Update the old prompt number if necessary.
content = msg['content']
previous_prompt_number = content['execution_count']
if self._previous_prompt_obj and \
self._previous_prompt_obj.number != previous_prompt_number:
block = self._previous_prompt_obj.block
# Make sure the prompt block has not been erased.
if block.isValid() and block.text():
# Remove the old prompt and insert a new prompt.
cursor = QtGui.QTextCursor(block)
cursor.movePosition(QtGui.QTextCursor.Right,
QtGui.QTextCursor.KeepAnchor,
self._previous_prompt_obj.length)
prompt = self._make_in_prompt(previous_prompt_number)
self._prompt = self._insert_html_fetching_plain_text(
cursor, prompt)
# When the HTML is inserted, Qt blows away the syntax
# highlighting for the line, so we need to rehighlight it.
self._highlighter.rehighlightBlock(cursor.block())
self._previous_prompt_obj = None
# Show a new prompt with the kernel's estimated prompt number.
self._show_interpreter_prompt(previous_prompt_number + 1)
#---------------------------------------------------------------------------
# 'IPythonWidget' interface
#---------------------------------------------------------------------------
def set_default_style(self, colors='lightbg'):
""" Sets the widget style to the class defaults.
Parameters:
-----------
colors : str, optional (default lightbg)
Whether to use the default IPython light background or dark
background or B&W style.
"""
colors = colors.lower()
if colors=='lightbg':
self.style_sheet = default_light_style_sheet
self.syntax_style = default_light_syntax_style
elif colors=='linux':
self.style_sheet = default_dark_style_sheet
self.syntax_style = default_dark_syntax_style
elif colors=='nocolor':
self.style_sheet = default_bw_style_sheet
self.syntax_style = default_bw_syntax_style
else:
raise KeyError("No such color scheme: %s"%colors)
#---------------------------------------------------------------------------
# 'IPythonWidget' protected interface
#---------------------------------------------------------------------------
def _edit(self, filename, line=None):
""" Opens a Python script for editing.
Parameters:
-----------
filename : str
A path to a local system file.
line : int, optional
A line of interest in the file.
"""
if self.custom_edit:
self.custom_edit_requested.emit(filename, line)
elif self.editor == 'default':
self._append_plain_text('No default editor available.\n')
else:
try:
filename = '"%s"' % filename
if line and self.editor_line:
command = self.editor_line.format(filename=filename,
line=line)
else:
try:
command = self.editor.format()
except KeyError:
command = self.editor.format(filename=filename)
else:
command += ' ' + filename
except KeyError:
self._append_plain_text('Invalid editor command.\n')
else:
try:
Popen(command, shell=True)
except OSError:
msg = 'Opening editor with command "%s" failed.\n'
self._append_plain_text(msg % command)
def _make_in_prompt(self, number):
""" Given a prompt number, returns an HTML In prompt.
"""
body = self.in_prompt % number
return '<span class="in-prompt">%s</span>' % body
def _make_continuation_prompt(self, prompt):
""" Given a plain text version of an In prompt, returns an HTML
continuation prompt.
"""
end_chars = '...: '
space_count = len(prompt.lstrip('\n')) - len(end_chars)
body = '&nbsp;' * space_count + end_chars
return '<span class="in-prompt">%s</span>' % body
def _make_out_prompt(self, number):
""" Given a prompt number, returns an HTML Out prompt.
"""
body = self.out_prompt % number
return '<span class="out-prompt">%s</span>' % body
#------ Payload handlers --------------------------------------------------
# Payload handlers with a generic interface: each takes the opaque payload
# dict, unpacks it and calls the underlying functions with the necessary
# arguments.
def _handle_payload_edit(self, item):
self._edit(item['filename'], item['line_number'])
def _handle_payload_exit(self, item):
self._keep_kernel_on_exit = item['keepkernel']
self.exit_requested.emit()
def _handle_payload_loadpy(self, item):
# Simple save the text of the .py file for later. The text is written
# to the buffer when _prompt_started_hook is called.
self._code_to_load = item['text']
def _handle_payload_page(self, item):
# Since the plain text widget supports only a very small subset of HTML
# and we have no control over the HTML source, we only page HTML
# payloads in the rich text widget.
if item['html'] and self.kind == 'rich':
self._page(item['html'], html=True)
else:
self._page(item['text'], html=False)
#------ Trait change handlers --------------------------------------------
def _style_sheet_changed(self):
""" Set the style sheets of the underlying widgets.
"""
self.setStyleSheet(self.style_sheet)
self._control.document().setDefaultStyleSheet(self.style_sheet)
if self._page_control:
self._page_control.document().setDefaultStyleSheet(self.style_sheet)
bg_color = self._control.palette().window().color()
self._ansi_processor.set_background_color(bg_color)
def _syntax_style_changed(self):
""" Set the style for the syntax highlighter.
"""
if self.syntax_style:
self._highlighter.set_style(self.syntax_style)
else:
self._highlighter.set_style_sheet(self.style_sheet)