""" A FrontendWidget that emulates the interface of the console IPython and
supports the additional functionality provided by the IPython kernel.
TODO: Add support for retrieving the system default editor. Requires code
paths for Windows (use the registry), Mac OS (use LaunchServices), and
Linux (use the xdg system).
"""
# Standard library imports
from subprocess import Popen
# System library imports
from PyQt4 import QtCore, QtGui
# Local imports
from IPython.core.inputsplitter import IPythonInputSplitter
from IPython.core.usage import default_banner
from frontend_widget import FrontendWidget
class IPythonPromptBlock(object):
""" An internal storage object for IPythonWidget.
"""
def __init__(self, block, length, number):
self.block = block
self.length = length
self.number = number
class IPythonWidget(FrontendWidget):
""" A FrontendWidget for an IPython kernel.
"""
# Signal emitted when an editor is needed for a file and the editor has been
# specified as 'custom'. See 'set_editor' for more information.
custom_edit_requested = QtCore.pyqtSignal(object, object)
# The default stylesheet: black text on a white background.
default_stylesheet = """
.error { color: red; }
.in-prompt { color: navy; }
.in-prompt-number { font-weight: bold; }
.out-prompt { color: darkred; }
.out-prompt-number { font-weight: bold; }
"""
# A dark stylesheet: white text on a black background.
dark_stylesheet = """
QPlainTextEdit, QTextEdit { background-color: black; color: white }
QFrame { border: 1px solid grey; }
.error { color: red; }
.in-prompt { color: lime; }
.in-prompt-number { color: lime; font-weight: bold; }
.out-prompt { color: red; }
.out-prompt-number { color: red; font-weight: bold; }
"""
# Default prompts.
in_prompt = 'In [%i]: '
out_prompt = 'Out[%i]: '
# FrontendWidget protected class variables.
#_input_splitter_class = IPythonInputSplitter
# IPythonWidget protected class variables.
_payload_source_edit = 'IPython.zmq.zmqshell.ZMQInteractiveShell.edit_magic'
_payload_source_page = 'IPython.zmq.page.page'
#---------------------------------------------------------------------------
# 'object' interface
#---------------------------------------------------------------------------
def __init__(self, *args, **kw):
super(IPythonWidget, self).__init__(*args, **kw)
# IPythonWidget protected variables.
self._previous_prompt_obj = None
# Set a default editor and stylesheet.
self.set_editor('default')
self.reset_styling()
#---------------------------------------------------------------------------
# 'BaseFrontendMixin' abstract interface
#---------------------------------------------------------------------------
def _handle_history_reply(self, msg):
""" Implemented to handle history replies, which are only supported by
the IPython kernel.
"""
history_dict = msg['content']['history']
items = [ history_dict[key] for key in sorted(history_dict.keys()) ]
self._set_history(items)
def _handle_prompt_reply(self, msg):
""" Implemented to handle prompt number replies, which are only
supported by the IPython kernel.
"""
content = msg['content']
self._show_interpreter_prompt(content['prompt_number'],
content['input_sep'])
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['prompt_number']
self._append_plain_text(content['output_sep'])
self._append_html(self._make_out_prompt(prompt_number))
self._append_plain_text(content['data'] + '\n' +
content['output_sep2'])
def _started_channels(self):
""" Reimplemented to make a history request.
"""
super(IPythonWidget, self)._started_channels()
# FIXME: Disabled until history requests are properly implemented.
#self.kernel_manager.xreq_channel.history(raw=True, output=False)
#---------------------------------------------------------------------------
# 'FrontendWidget' 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 _get_banner(self):
""" Reimplemented to return IPython's default banner.
"""
return default_banner + '\n'
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(' ', ' ')
traceback = traceback.replace('\n', '
')
ename = content['ename']
ename_styled = '%s' % 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 handle %edit and paging payloads.
"""
if item['source'] == self._payload_source_edit:
self._edit(item['filename'], item['line_number'])
return True
elif item['source'] == self._payload_source_page:
self._page(item['data'])
return True
else:
return False
def _show_interpreter_prompt(self, number=None, input_sep='\n'):
""" Reimplemented for IPython-style prompts.
"""
# If a number was not specified, make a prompt number request.
if number is None:
self.kernel_manager.xreq_channel.prompt()
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._append_plain_text(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 = IPythonPromptBlock(block, length, number)
# Update continuation prompt to reflect (possibly) new prompt length.
self._set_continuation_prompt(
self._make_continuation_prompt(self._prompt), html=True)
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['prompt_number']
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 not block.text().isEmpty():
# 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.
next_prompt = content['next_prompt']
self._show_interpreter_prompt(next_prompt['prompt_number'],
next_prompt['input_sep'])
#---------------------------------------------------------------------------
# 'IPythonWidget' interface
#---------------------------------------------------------------------------
def reset_styling(self):
""" Restores the default IPythonWidget styling.
"""
self.set_styling(self.default_stylesheet, syntax_style='default')
#self.set_styling(self.dark_stylesheet, syntax_style='monokai')
def set_editor(self, editor, line_editor=None):
""" Sets the editor to use with the %edit magic.
Parameters:
-----------
editor : str
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.
This parameter also takes a special value:
'custom' : Emit a 'custom_edit_requested(str, int)' signal
instead of opening an editor.
line_editor : str, optional
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.
"""
self._editor = editor
self._editor_line = line_editor
def set_styling(self, stylesheet, syntax_style=None):
""" Sets the IPythonWidget styling.
Parameters:
-----------
stylesheet : str
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.
syntax_style : str or None [default None]
If specified, use the Pygments style with given name. Otherwise,
the stylesheet is queried for Pygments style information.
"""
self.setStyleSheet(stylesheet)
self._control.document().setDefaultStyleSheet(stylesheet)
if self._page_control:
self._page_control.document().setDefaultStyleSheet(stylesheet)
if syntax_style is None:
self._highlighter.set_style_sheet(stylesheet)
else:
self._highlighter.set_style(syntax_style)
#---------------------------------------------------------------------------
# '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._editor == 'custom':
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 '%s' % 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 = ' ' * space_count + end_chars
return '%s' % body
def _make_out_prompt(self, number):
""" Given a prompt number, returns an HTML Out prompt.
"""
body = self.out_prompt % number
return '%s' % body