# System library imports from pygments.lexers import PythonLexer from PyQt4 import QtCore, QtGui import zmq # Local imports from IPython.core.inputsplitter import InputSplitter from call_tip_widget import CallTipWidget from completion_lexer import CompletionLexer from console_widget import HistoryConsoleWidget from pygments_highlighter import PygmentsHighlighter class FrontendHighlighter(PygmentsHighlighter): """ A Python PygmentsHighlighter that can be turned on and off and which knows about continuation prompts. """ def __init__(self, frontend): PygmentsHighlighter.__init__(self, frontend.document(), PythonLexer()) self._current_offset = 0 self._frontend = frontend self.highlighting_on = False def highlightBlock(self, qstring): """ Highlight a block of text. Reimplemented to highlight selectively. """ if self.highlighting_on: for prompt in (self._frontend._continuation_prompt, self._frontend._prompt): if qstring.startsWith(prompt): qstring.remove(0, len(prompt)) self._current_offset = len(prompt) break PygmentsHighlighter.highlightBlock(self, qstring) def setFormat(self, start, count, format): """ Reimplemented to avoid highlighting continuation prompts. """ start += self._current_offset PygmentsHighlighter.setFormat(self, start, count, format) class FrontendWidget(HistoryConsoleWidget): """ A Qt frontend for a generic Python kernel. """ # Emitted when an 'execute_reply' is received from the kernel. executed = QtCore.pyqtSignal(object) #--------------------------------------------------------------------------- # 'QObject' interface #--------------------------------------------------------------------------- def __init__(self, parent=None): super(FrontendWidget, self).__init__(parent) # ConsoleWidget protected variables. self._continuation_prompt = '... ' self._prompt = '>>> ' # FrontendWidget protected variables. self._call_tip_widget = CallTipWidget(self) self._completion_lexer = CompletionLexer(PythonLexer()) self._hidden = True self._highlighter = FrontendHighlighter(self) self._input_splitter = InputSplitter(input_mode='replace') self._kernel_manager = None self.document().contentsChange.connect(self._document_contents_change) #--------------------------------------------------------------------------- # 'QWidget' interface #--------------------------------------------------------------------------- def focusOutEvent(self, event): """ Reimplemented to hide calltips. """ self._call_tip_widget.hide() return super(FrontendWidget, self).focusOutEvent(event) def keyPressEvent(self, event): """ Reimplemented to hide calltips. """ if event.key() == QtCore.Qt.Key_Escape: self._call_tip_widget.hide() return super(FrontendWidget, self).keyPressEvent(event) #--------------------------------------------------------------------------- # 'ConsoleWidget' abstract interface #--------------------------------------------------------------------------- def _execute(self, interactive): """ Called to execute the input buffer. When triggered by an the enter key press, 'interactive' is True; otherwise, it is False. Returns whether the input buffer was completely processed and a new prompt created. """ return self.execute_source(self.input_buffer, interactive=interactive) def _prompt_started_hook(self): """ Called immediately after a new prompt is displayed. """ self._highlighter.highlighting_on = True def _prompt_finished_hook(self): """ Called immediately after a prompt is finished, i.e. when some input will be processed and a new prompt displayed. """ self._highlighter.highlighting_on = False def _tab_pressed(self): """ Called when the tab key is pressed. Returns whether to continue processing the event. """ self._keep_cursor_in_buffer() cursor = self.textCursor() if not self._complete(): cursor.insertText(' ') return False #--------------------------------------------------------------------------- # 'FrontendWidget' interface #--------------------------------------------------------------------------- def execute_source(self, source, hidden=False, interactive=False): """ Execute a string containing Python code. If 'hidden', no output is shown. Returns whether the source executed (i.e., returns True only if no more input is necessary). """ self._input_splitter.push(source) executed = not self._input_splitter.push_accepts_more() if executed: self.kernel_manager.xreq_channel.execute(source) self._hidden = hidden else: self._show_continuation_prompt() self.appendPlainText(' ' * self._input_splitter.indent_spaces) return executed def execute_file(self, path, hidden=False): """ Attempts to execute file with 'path'. If 'hidden', no output is shown. """ self.execute_source('run %s' % path, hidden=hidden) def _get_kernel_manager(self): """ Returns the current kernel manager. """ return self._kernel_manager def _set_kernel_manager(self, kernel_manager): """ Disconnect from the current kernel manager (if any) and set a new kernel manager. """ # Disconnect the old kernel manager, if necessary. if self._kernel_manager is not None: self._kernel_manager.started_listening.disconnect( self._started_listening) self._kernel_manager.stopped_listening.disconnect( self._stopped_listening) # Disconnect the old kernel manager's channels. sub = self._kernel_manager.sub_channel xreq = self._kernel_manager.xreq_channel sub.message_received.disconnect(self._handle_sub) xreq.execute_reply.disconnect(self._handle_execute_reply) xreq.complete_reply.disconnect(self._handle_complete_reply) xreq.object_info_reply.disconnect(self._handle_object_info_reply) # Set the new kernel manager. self._kernel_manager = kernel_manager if kernel_manager is None: return # Connect the new kernel manager. kernel_manager.started_listening.connect(self._started_listening) kernel_manager.stopped_listening.connect(self._stopped_listening) # Connect the new kernel manager's channels. sub = kernel_manager.sub_channel xreq = kernel_manager.xreq_channel sub.message_received.connect(self._handle_sub) xreq.execute_reply.connect(self._handle_execute_reply) xreq.complete_reply.connect(self._handle_complete_reply) xreq.object_info_reply.connect(self._handle_object_info_reply) # Handle the case where the kernel manager started listening before # we connected. if kernel_manager.is_listening: self._started_listening() kernel_manager = property(_get_kernel_manager, _set_kernel_manager) #--------------------------------------------------------------------------- # 'FrontendWidget' protected interface #--------------------------------------------------------------------------- def _call_tip(self): """ Shows a call tip, if appropriate, at the current cursor location. """ # Decide if it makes sense to show a call tip cursor = self.textCursor() cursor.movePosition(QtGui.QTextCursor.Left) document = self.document() if document.characterAt(cursor.position()).toAscii() != '(': return False context = self._get_context(cursor) if not context: return False # Send the metadata request to the kernel name = '.'.join(context) self._calltip_id = self.kernel_manager.xreq_channel.object_info(name) self._calltip_pos = self.textCursor().position() return True def _complete(self): """ Performs completion at the current cursor location. """ # Decide if it makes sense to do completion context = self._get_context() if not context: return False # Send the completion request to the kernel text = '.'.join(context) self._complete_id = self.kernel_manager.xreq_channel.complete( text, self.input_buffer_cursor_line, self.input_buffer) self._complete_pos = self.textCursor().position() return True def _get_context(self, cursor=None): """ Gets the context at the current cursor location. """ if cursor is None: cursor = self.textCursor() cursor.movePosition(QtGui.QTextCursor.StartOfLine, QtGui.QTextCursor.KeepAnchor) text = unicode(cursor.selectedText()) return self._completion_lexer.get_context(text) #------ Signal handlers ---------------------------------------------------- def _document_contents_change(self, position, removed, added): """ Called whenever the document's content changes. Display a calltip if appropriate. """ # Calculate where the cursor should be *after* the change: position += added document = self.document() if position == self.textCursor().position(): self._call_tip() def _handle_sub(self, omsg): if not self._hidden: handler = getattr(self, '_handle_%s' % omsg['msg_type'], None) if handler is not None: handler(omsg) def _handle_pyout(self, omsg): session = omsg['parent_header']['session'] if session == self.kernel_manager.session.session: self.appendPlainText(omsg['content']['data'] + '\n') def _handle_stream(self, omsg): self.appendPlainText(omsg['content']['data']) def _handle_execute_reply(self, rep): # Make sure that all output from the SUB channel has been processed # before writing a new prompt. self.kernel_manager.sub_channel.flush() content = rep['content'] status = content['status'] if status == 'error': self.appendPlainText(content['traceback'][-1]) elif status == 'aborted': text = "ERROR: ABORTED\n" self.appendPlainText(text) self._hidden = True self._show_prompt() self.executed.emit(rep) def _handle_complete_reply(self, rep): cursor = self.textCursor() if rep['parent_header']['msg_id'] == self._complete_id and \ cursor.position() == self._complete_pos: text = '.'.join(self._get_context()) cursor.movePosition(QtGui.QTextCursor.Left, n=len(text)) self._complete_with_items(cursor, rep['content']['matches']) def _handle_object_info_reply(self, rep): cursor = self.textCursor() if rep['parent_header']['msg_id'] == self._calltip_id and \ cursor.position() == self._calltip_pos: doc = rep['content']['docstring'] if doc: self._call_tip_widget.show_docstring(doc) def _started_listening(self): self.clear() def _stopped_listening(self): pass