add ConsoleWidget.include_other_output

matches zmq console. Doesn't include `[remote] ` prefix,
because true async output makes it less important.

IPython/qt/base_frontend_mixin.py

@@ -1,150 +1,158 b''
 """ Defines a convenient mix-in class for implementing Qt frontends.
 """
 
 class BaseFrontendMixin(object):
     """ A mix-in class for implementing Qt frontends.
 
     To handle messages of a particular type, frontends need only define an
     appropriate handler method. For example, to handle 'stream' messaged, define
     a '_handle_stream(msg)' method.
     """
 
     #---------------------------------------------------------------------------
     # 'BaseFrontendMixin' concrete interface
     #---------------------------------------------------------------------------
     _kernel_client = None
     _kernel_manager = None
 
     @property
     def kernel_client(self):
         """Returns the current kernel client."""
         return self._kernel_client
 
     @kernel_client.setter
     def kernel_client(self, kernel_client):
         """Disconnect from the current kernel client (if any) and set a new
             kernel client.
         """
         # Disconnect the old kernel client, if necessary.
         old_client = self._kernel_client
         if old_client is not None:
             old_client.started_channels.disconnect(self._started_channels)
             old_client.stopped_channels.disconnect(self._stopped_channels)
 
             # Disconnect the old kernel client's channels.
             old_client.iopub_channel.message_received.disconnect(self._dispatch)
             old_client.shell_channel.message_received.disconnect(self._dispatch)
             old_client.stdin_channel.message_received.disconnect(self._dispatch)
             old_client.hb_channel.kernel_died.disconnect(
                 self._handle_kernel_died)
 
             # Handle the case where the old kernel client is still listening.
             if old_client.channels_running:
                 self._stopped_channels()
 
         # Set the new kernel client.
         self._kernel_client = kernel_client
         if kernel_client is None:
             return
 
         # Connect the new kernel client.
         kernel_client.started_channels.connect(self._started_channels)
         kernel_client.stopped_channels.connect(self._stopped_channels)
 
         # Connect the new kernel client's channels.
         kernel_client.iopub_channel.message_received.connect(self._dispatch)
         kernel_client.shell_channel.message_received.connect(self._dispatch)
         kernel_client.stdin_channel.message_received.connect(self._dispatch)
         # hb_channel
         kernel_client.hb_channel.kernel_died.connect(self._handle_kernel_died)
 
         # Handle the case where the kernel client started channels before
         # we connected.
         if kernel_client.channels_running:
             self._started_channels()
 
     @property
     def kernel_manager(self):
         """The kernel manager, if any"""
         return self._kernel_manager
 
     @kernel_manager.setter
     def kernel_manager(self, kernel_manager):
         old_man = self._kernel_manager
         if old_man is not None:
             old_man.kernel_restarted.disconnect(self._handle_kernel_restarted)
 
         self._kernel_manager = kernel_manager
         if kernel_manager is None:
             return
 
         kernel_manager.kernel_restarted.connect(self._handle_kernel_restarted)
 
     #---------------------------------------------------------------------------
     # 'BaseFrontendMixin' abstract interface
     #---------------------------------------------------------------------------
 
     def _handle_kernel_died(self, since_last_heartbeat):
         """ This is called when the ``kernel_died`` signal is emitted.
 
         This method is called when the kernel heartbeat has not been
         active for a certain amount of time.
         This is a strictly passive notification -
         the kernel is likely being restarted by its KernelManager.
 
         Parameters
         ----------
         since_last_heartbeat : float
             The time since the heartbeat was last received.
         """
 
     def _handle_kernel_restarted(self):
         """ This is called when the ``kernel_restarted`` signal is emitted.
 
         This method is called when the kernel has been restarted by the
         autorestart mechanism.
 
         Parameters
         ----------
         since_last_heartbeat : float
             The time since the heartbeat was last received.
         """
     def _started_kernel(self):
         """Called when the KernelManager starts (or restarts) the kernel subprocess.
         Channels may or may not be running at this point.
         """
 
     def _started_channels(self):
         """ Called when the KernelManager channels have started listening or
             when the frontend is assigned an already listening KernelManager.
         """
 
     def _stopped_channels(self):
         """ Called when the KernelManager channels have stopped listening or
             when a listening KernelManager is removed from the frontend.
         """
 
     #---------------------------------------------------------------------------
     # 'BaseFrontendMixin' protected interface
     #---------------------------------------------------------------------------
 
     def _dispatch(self, msg):
         """ Calls the frontend handler associated with the message type of the
             given message.
         """
         msg_type = msg['header']['msg_type']
         handler = getattr(self, '_handle_' + msg_type, None)
         if handler:
             handler(msg)
-
-    def _is_from_this_session(self, msg):
-        """ Returns whether a reply from the kernel originated from a request
-            from this frontend.
-        """
-        session = self._kernel_client.session.session
-        parent = msg['parent_header']
-        if not parent:
-            # if the message has no parent, assume it is meant for all frontends
+    
+    def from_here(self, msg):
+        """Return whether a message is from this session"""
+        session_id = self._kernel_client.session.session
+        return msg['parent_header'].get("session", session_id) == session_id
+    
+    def include_output(self, msg):
+        """Return whether we should include a given output message"""
+        if self._hidden:
+            return False
+        from_here = self.from_here(msg)
+        if msg['msg_type'] == 'execute_input':
+            # only echo inputs not from here
+            return self.include_other_output and not from_here
+        
+        if self.include_other_output:
             return True
         else:
-            return parent.get('session') == session
+            return from_here
+    

IPython/qt/console/console_widget.py

@@ -1,2155 +1,2163 b''
 """ An abstract base class for console-type widgets.
 """
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Standard library imports
 import os.path
 import re
 import sys
 from textwrap import dedent
 import time
 from unicodedata import category
 import webbrowser
 
 # System library imports
 from IPython.external.qt import QtCore, QtGui
 
 # Local imports
 from IPython.config.configurable import LoggingConfigurable
 from IPython.core.inputsplitter import ESC_SEQUENCES
 from IPython.qt.rich_text import HtmlExporter
 from IPython.qt.util import MetaQObjectHasTraits, get_font
 from IPython.utils.text import columnize
 from IPython.utils.traitlets import Bool, Enum, Integer, Unicode
 from .ansi_code_processor import QtAnsiCodeProcessor
 from .completion_widget import CompletionWidget
 from .completion_html import CompletionHtml
 from .completion_plain import CompletionPlain
 from .kill_ring import QtKillRing
 
 
 #-----------------------------------------------------------------------------
 # Functions
 #-----------------------------------------------------------------------------
 
 ESCAPE_CHARS = ''.join(ESC_SEQUENCES)
 ESCAPE_RE = re.compile("^["+ESCAPE_CHARS+"]+")
 
 def commonprefix(items):
     """Get common prefix for completions
 
     Return the longest common prefix of a list of strings, but with special
     treatment of escape characters that might precede commands in IPython,
     such as %magic functions. Used in tab completion.
 
     For a more general function, see os.path.commonprefix
     """
     # the last item will always have the least leading % symbol
     # min / max are first/last in alphabetical order
     first_match  = ESCAPE_RE.match(min(items))
     last_match  = ESCAPE_RE.match(max(items))
     # common suffix is (common prefix of reversed items) reversed
     if first_match and last_match:
         prefix = os.path.commonprefix((first_match.group(0)[::-1], last_match.group(0)[::-1]))[::-1]
     else:
         prefix = ''
 
     items = [s.lstrip(ESCAPE_CHARS) for s in items]
     return prefix+os.path.commonprefix(items)
 
 def is_letter_or_number(char):
     """ Returns whether the specified unicode character is a letter or a number.
     """
     cat = category(char)
     return cat.startswith('L') or cat.startswith('N')
 
 #-----------------------------------------------------------------------------
 # Classes
 #-----------------------------------------------------------------------------
 
 class ConsoleWidget(MetaQObjectHasTraits('NewBase', (LoggingConfigurable, QtGui.QWidget), {})):
     """ An abstract base class for console-type widgets. This class has
         functionality for:
 
             * Maintaining a prompt and editing region
             * Providing the traditional Unix-style console keyboard shortcuts
             * Performing tab completion
             * Paging text
             * Handling ANSI escape codes
 
         ConsoleWidget also provides a number of utility methods that will be
         convenient to implementors of a console-style widget.
     """
 
     #------ Configuration ------------------------------------------------------
 
     ansi_codes = Bool(True, config=True,
         help="Whether to process ANSI escape codes."
     )
     buffer_size = Integer(500, config=True,
         help="""
         The maximum number of lines of text before truncation. Specifying a
         non-positive number disables text truncation (not recommended).
         """
     )
     execute_on_complete_input = Bool(True, config=True,
         help="""Whether to automatically execute on syntactically complete input.
         
         If False, Shift-Enter is required to submit each execution.
         Disabling this is mainly useful for non-Python kernels,
         where the completion check would be wrong.
         """
     )
     gui_completion = Enum(['plain', 'droplist', 'ncurses'], config=True,
                     default_value = 'ncurses',
                     help="""
                     The type of completer to use. Valid values are:
 
                     'plain'   : Show the available completion as a text list
                                 Below the editing area.
                     'droplist': Show the completion in a drop down list navigable
                                 by the arrow keys, and from which you can select
                                 completion by pressing Return.
                     'ncurses' : Show the completion as a text list which is navigable by
                                 `tab` and arrow keys.
                     """
     )
     # NOTE: this value can only be specified during initialization.
     kind = Enum(['plain', 'rich'], default_value='plain', config=True,
         help="""
         The type of underlying text widget to use. Valid values are 'plain',
         which specifies a QPlainTextEdit, and 'rich', which specifies a
         QTextEdit.
         """
     )
     # NOTE: this value can only be specified during initialization.
     paging = Enum(['inside', 'hsplit', 'vsplit', 'custom', 'none'],
                   default_value='inside', config=True,
         help="""
         The type of paging to use. Valid values are:
 
         'inside'
            The widget pages like a traditional terminal.
         'hsplit'
            When paging is requested, the widget is split horizontally. The top
            pane contains the console, and the bottom pane contains the paged text.
         'vsplit'
            Similar to 'hsplit', except that a vertical splitter is used.
         'custom'
            No action is taken by the widget beyond emitting a
            'custom_page_requested(str)' signal.
         'none'
            The text is written directly to the console.
         """)
 
     font_family = Unicode(config=True,
         help="""The font family to use for the console.
         On OSX this defaults to Monaco, on Windows the default is
         Consolas with fallback of Courier, and on other platforms
         the default is Monospace.
         """)
     def _font_family_default(self):
         if sys.platform == 'win32':
             # Consolas ships with Vista/Win7, fallback to Courier if needed
             return 'Consolas'
         elif sys.platform == 'darwin':
             # OSX always has Monaco, no need for a fallback
             return 'Monaco'
         else:
             # Monospace should always exist, no need for a fallback
             return 'Monospace'
 
     font_size = Integer(config=True,
         help="""The font size. If unconfigured, Qt will be entrusted
         with the size of the font.
         """)
 
     width = Integer(81, config=True,
         help="""The width of the console at start time in number
         of characters (will double with `hsplit` paging)
         """)
 
     height = Integer(25, config=True,
         help="""The height of the console at start time in number
         of characters (will double with `vsplit` paging)
         """)
 
     # Whether to override ShortcutEvents for the keybindings defined by this
     # widget (Ctrl+n, Ctrl+a, etc). Enable this if you want this widget to take
     # priority (when it has focus) over, e.g., window-level menu shortcuts.
     override_shortcuts = Bool(False)
     
     # ------ Custom Qt Widgets -------------------------------------------------
     
     # For other projects to easily override the Qt widgets used by the console
     # (e.g. Spyder)
     custom_control = None
     custom_page_control = None
 
     #------ Signals ------------------------------------------------------------
 
     # Signals that indicate ConsoleWidget state.
     copy_available = QtCore.Signal(bool)
     redo_available = QtCore.Signal(bool)
     undo_available = QtCore.Signal(bool)
 
     # Signal emitted when paging is needed and the paging style has been
     # specified as 'custom'.
     custom_page_requested = QtCore.Signal(object)
 
     # Signal emitted when the font is changed.
     font_changed = QtCore.Signal(QtGui.QFont)
 
     #------ Protected class variables ------------------------------------------
 
     # control handles
     _control = None
     _page_control = None
     _splitter = None
 
     # When the control key is down, these keys are mapped.
     _ctrl_down_remap = { QtCore.Qt.Key_B : QtCore.Qt.Key_Left,
                          QtCore.Qt.Key_F : QtCore.Qt.Key_Right,
                          QtCore.Qt.Key_A : QtCore.Qt.Key_Home,
                          QtCore.Qt.Key_P : QtCore.Qt.Key_Up,
                          QtCore.Qt.Key_N : QtCore.Qt.Key_Down,
                          QtCore.Qt.Key_H : QtCore.Qt.Key_Backspace, }
     if not sys.platform == 'darwin':
         # On OS X, Ctrl-E already does the right thing, whereas End moves the
         # cursor to the bottom of the buffer.
         _ctrl_down_remap[QtCore.Qt.Key_E] = QtCore.Qt.Key_End
 
     # The shortcuts defined by this widget. We need to keep track of these to
     # support 'override_shortcuts' above.
     _shortcuts = set(_ctrl_down_remap.keys()) | \
                      { QtCore.Qt.Key_C, QtCore.Qt.Key_G, QtCore.Qt.Key_O,
                        QtCore.Qt.Key_V }
 
     _temp_buffer_filled = False
 
     #---------------------------------------------------------------------------
     # 'QObject' interface
     #---------------------------------------------------------------------------
 
     def __init__(self, parent=None, **kw):
         """ Create a ConsoleWidget.
 
         Parameters
         ----------
         parent : QWidget, optional [default None]
             The parent for this widget.
         """
         QtGui.QWidget.__init__(self, parent)
         LoggingConfigurable.__init__(self, **kw)
 
         # While scrolling the pager on Mac OS X, it tears badly.  The
         # NativeGesture is platform and perhaps build-specific hence
         # we take adequate precautions here.
         self._pager_scroll_events = [QtCore.QEvent.Wheel]
         if hasattr(QtCore.QEvent, 'NativeGesture'):
             self._pager_scroll_events.append(QtCore.QEvent.NativeGesture)
 
         # Create the layout and underlying text widget.
         layout = QtGui.QStackedLayout(self)
         layout.setContentsMargins(0, 0, 0, 0)
         self._control = self._create_control()
         if self.paging in ('hsplit', 'vsplit'):
             self._splitter = QtGui.QSplitter()
             if self.paging == 'hsplit':
                 self._splitter.setOrientation(QtCore.Qt.Horizontal)
             else:
                 self._splitter.setOrientation(QtCore.Qt.Vertical)
             self._splitter.addWidget(self._control)
             layout.addWidget(self._splitter)
         else:
             layout.addWidget(self._control)
 
         # Create the paging widget, if necessary.
         if self.paging in ('inside', 'hsplit', 'vsplit'):
             self._page_control = self._create_page_control()
             if self._splitter:
                 self._page_control.hide()
                 self._splitter.addWidget(self._page_control)
             else:
                 layout.addWidget(self._page_control)
 
         # Initialize protected variables. Some variables contain useful state
         # information for subclasses; they should be considered read-only.
         self._append_before_prompt_pos = 0
         self._ansi_processor = QtAnsiCodeProcessor()
         if self.gui_completion == 'ncurses':
             self._completion_widget = CompletionHtml(self)
         elif self.gui_completion == 'droplist':
             self._completion_widget = CompletionWidget(self)
         elif self.gui_completion == 'plain':
             self._completion_widget = CompletionPlain(self)
 
         self._continuation_prompt = '> '
         self._continuation_prompt_html = None
         self._executing = False
         self._filter_resize = False
         self._html_exporter = HtmlExporter(self._control)
         self._input_buffer_executing = ''
         self._input_buffer_pending = ''
         self._kill_ring = QtKillRing(self._control)
         self._prompt = ''
         self._prompt_html = None
         self._prompt_pos = 0
         self._prompt_sep = ''
         self._reading = False
         self._reading_callback = None
         self._tab_width = 8
 
         # List of strings pending to be appended as plain text in the widget.
         # The text is not immediately inserted when available to not
         # choke the Qt event loop with paint events for the widget in
         # case of lots of output from kernel.
         self._pending_insert_text = []
 
         # Timer to flush the pending stream messages. The interval is adjusted
         # later based on actual time taken for flushing a screen (buffer_size)
         # of output text.
         self._pending_text_flush_interval = QtCore.QTimer(self._control)
         self._pending_text_flush_interval.setInterval(100)
         self._pending_text_flush_interval.setSingleShot(True)
         self._pending_text_flush_interval.timeout.connect(
                                             self._on_flush_pending_stream_timer)
 
         # Set a monospaced font.
         self.reset_font()
 
         # Configure actions.
         action = QtGui.QAction('Print', None)
         action.setEnabled(True)
         printkey = QtGui.QKeySequence(QtGui.QKeySequence.Print)
         if printkey.matches("Ctrl+P") and sys.platform != 'darwin':
             # Only override the default if there is a collision.
             # Qt ctrl = cmd on OSX, so the match gets a false positive on OSX.
             printkey = "Ctrl+Shift+P"
         action.setShortcut(printkey)
         action.setShortcutContext(QtCore.Qt.WidgetWithChildrenShortcut)
         action.triggered.connect(self.print_)
         self.addAction(action)
         self.print_action = action
 
         action = QtGui.QAction('Save as HTML/XML', None)
         action.setShortcut(QtGui.QKeySequence.Save)
         action.setShortcutContext(QtCore.Qt.WidgetWithChildrenShortcut)
         action.triggered.connect(self.export_html)
         self.addAction(action)
         self.export_action = action
 
         action = QtGui.QAction('Select All', None)
         action.setEnabled(True)
         selectall = QtGui.QKeySequence(QtGui.QKeySequence.SelectAll)
         if selectall.matches("Ctrl+A") and sys.platform != 'darwin':
             # Only override the default if there is a collision.
             # Qt ctrl = cmd on OSX, so the match gets a false positive on OSX.
             selectall = "Ctrl+Shift+A"
         action.setShortcut(selectall)
         action.setShortcutContext(QtCore.Qt.WidgetWithChildrenShortcut)
         action.triggered.connect(self.select_all)
         self.addAction(action)
         self.select_all_action = action
 
         self.increase_font_size = QtGui.QAction("Bigger Font",
                 self,
                 shortcut=QtGui.QKeySequence.ZoomIn,
                 shortcutContext=QtCore.Qt.WidgetWithChildrenShortcut,
                 statusTip="Increase the font size by one point",
                 triggered=self._increase_font_size)
         self.addAction(self.increase_font_size)
 
         self.decrease_font_size = QtGui.QAction("Smaller Font",
                 self,
                 shortcut=QtGui.QKeySequence.ZoomOut,
                 shortcutContext=QtCore.Qt.WidgetWithChildrenShortcut,
                 statusTip="Decrease the font size by one point",
                 triggered=self._decrease_font_size)
         self.addAction(self.decrease_font_size)
 
         self.reset_font_size = QtGui.QAction("Normal Font",
                 self,
                 shortcut="Ctrl+0",
                 shortcutContext=QtCore.Qt.WidgetWithChildrenShortcut,
                 statusTip="Restore the Normal font size",
                 triggered=self.reset_font)
         self.addAction(self.reset_font_size)
 
         # Accept drag and drop events here. Drops were already turned off
         # in self._control when that widget was created.
         self.setAcceptDrops(True)
 
     #---------------------------------------------------------------------------
     # Drag and drop support
     #---------------------------------------------------------------------------
 
     def dragEnterEvent(self, e):
         if e.mimeData().hasUrls():
             # The link action should indicate to that the drop will insert
             # the file anme.
             e.setDropAction(QtCore.Qt.LinkAction)
             e.accept()
         elif e.mimeData().hasText():
             # By changing the action to copy we don't need to worry about
             # the user accidentally moving text around in the widget.
             e.setDropAction(QtCore.Qt.CopyAction)
             e.accept()
 
     def dragMoveEvent(self, e):
         if e.mimeData().hasUrls():
             pass
         elif e.mimeData().hasText():
             cursor = self._control.cursorForPosition(e.pos())
             if self._in_buffer(cursor.position()):
                 e.setDropAction(QtCore.Qt.CopyAction)
                 self._control.setTextCursor(cursor)
             else:
                 e.setDropAction(QtCore.Qt.IgnoreAction)
             e.accept()
 
     def dropEvent(self, e):
         if e.mimeData().hasUrls():
             self._keep_cursor_in_buffer()
             cursor = self._control.textCursor()
             filenames = [url.toLocalFile() for url in e.mimeData().urls()]
             text = ', '.join("'" + f.replace("'", "'\"'\"'") + "'"
                              for f in filenames)
             self._insert_plain_text_into_buffer(cursor, text)
         elif e.mimeData().hasText():
             cursor = self._control.cursorForPosition(e.pos())
             if self._in_buffer(cursor.position()):
                 text = e.mimeData().text()
                 self._insert_plain_text_into_buffer(cursor, text)
 
     def eventFilter(self, obj, event):
         """ Reimplemented to ensure a console-like behavior in the underlying
             text widgets.
         """
         etype = event.type()
         if etype == QtCore.QEvent.KeyPress:
 
             # Re-map keys for all filtered widgets.
             key = event.key()
             if self._control_key_down(event.modifiers()) and \
                     key in self._ctrl_down_remap:
                 new_event = QtGui.QKeyEvent(QtCore.QEvent.KeyPress,
                                             self._ctrl_down_remap[key],
                                             QtCore.Qt.NoModifier)
                 QtGui.qApp.sendEvent(obj, new_event)
                 return True
 
             elif obj == self._control:
                 return self._event_filter_console_keypress(event)
 
             elif obj == self._page_control:
                 return self._event_filter_page_keypress(event)
 
         # Make middle-click paste safe.
         elif etype == QtCore.QEvent.MouseButtonRelease and \
                 event.button() == QtCore.Qt.MidButton and \
                 obj == self._control.viewport():
             cursor = self._control.cursorForPosition(event.pos())
             self._control.setTextCursor(cursor)
             self.paste(QtGui.QClipboard.Selection)
             return True
 
         # Manually adjust the scrollbars *after* a resize event is dispatched.
         elif etype == QtCore.QEvent.Resize and not self._filter_resize:
             self._filter_resize = True
             QtGui.qApp.sendEvent(obj, event)
             self._adjust_scrollbars()
             self._filter_resize = False
             return True
 
         # Override shortcuts for all filtered widgets.
         elif etype == QtCore.QEvent.ShortcutOverride and \
                 self.override_shortcuts and \
                 self._control_key_down(event.modifiers()) and \
                 event.key() in self._shortcuts:
             event.accept()
 
         # Handle scrolling of the vsplit pager. This hack attempts to solve
         # problems with tearing of the help text inside the pager window.  This
         # happens only on Mac OS X with both PySide and PyQt. This fix isn't
         # perfect but makes the pager more usable.
         elif etype in self._pager_scroll_events and \
                 obj == self._page_control:
             self._page_control.repaint()
             return True
 
         elif etype == QtCore.QEvent.MouseMove:
             anchor = self._control.anchorAt(event.pos())
             QtGui.QToolTip.showText(event.globalPos(), anchor)
 
         return super(ConsoleWidget, self).eventFilter(obj, event)
 
     #---------------------------------------------------------------------------
     # 'QWidget' interface
     #---------------------------------------------------------------------------
 
     def sizeHint(self):
         """ Reimplemented to suggest a size that is 80 characters wide and
             25 lines high.
         """
         font_metrics = QtGui.QFontMetrics(self.font)
         margin = (self._control.frameWidth() +
                   self._control.document().documentMargin()) * 2
         style = self.style()
         splitwidth = style.pixelMetric(QtGui.QStyle.PM_SplitterWidth)
 
         # Note 1: Despite my best efforts to take the various margins into
         # account, the width is still coming out a bit too small, so we include
         # a fudge factor of one character here.
         # Note 2: QFontMetrics.maxWidth is not used here or anywhere else due
         # to a Qt bug on certain Mac OS systems where it returns 0.
         width = font_metrics.width(' ') * self.width + margin
         width += style.pixelMetric(QtGui.QStyle.PM_ScrollBarExtent)
         if self.paging == 'hsplit':
             width = width * 2 + splitwidth
 
         height = font_metrics.height() * self.height + margin
         if self.paging == 'vsplit':
             height = height * 2 + splitwidth
 
         return QtCore.QSize(width, height)
 
     #---------------------------------------------------------------------------
     # 'ConsoleWidget' public interface
     #---------------------------------------------------------------------------
-
+    
+    include_other_output = Bool(False, config=True,
+        help="""Whether to include output from clients
+        other than this one sharing the same kernel.
+        
+        Outputs are not displayed until enter is pressed.
+        """
+    )
+    
     def can_copy(self):
         """ Returns whether text can be copied to the clipboard.
         """
         return self._control.textCursor().hasSelection()
 
     def can_cut(self):
         """ Returns whether text can be cut to the clipboard.
         """
         cursor = self._control.textCursor()
         return (cursor.hasSelection() and
                 self._in_buffer(cursor.anchor()) and
                 self._in_buffer(cursor.position()))
 
     def can_paste(self):
         """ Returns whether text can be pasted from the clipboard.
         """
         if self._control.textInteractionFlags() & QtCore.Qt.TextEditable:
             return bool(QtGui.QApplication.clipboard().text())
         return False
 
     def clear(self, keep_input=True):
         """ Clear the console.
 
         Parameters
         ----------
         keep_input : bool, optional (default True)
             If set, restores the old input buffer if a new prompt is written.
         """
         if self._executing:
             self._control.clear()
         else:
             if keep_input:
                 input_buffer = self.input_buffer
             self._control.clear()
             self._show_prompt()
             if keep_input:
                 self.input_buffer = input_buffer
 
     def copy(self):
         """ Copy the currently selected text to the clipboard.
         """
         self.layout().currentWidget().copy()
 
     def copy_anchor(self, anchor):
         """ Copy anchor text to the clipboard
         """
         QtGui.QApplication.clipboard().setText(anchor)
 
     def cut(self):
         """ Copy the currently selected text to the clipboard and delete it
             if it's inside the input buffer.
         """
         self.copy()
         if self.can_cut():
             self._control.textCursor().removeSelectedText()
 
     def execute(self, source=None, hidden=False, interactive=False):
         """ Executes source or the input buffer, possibly prompting for more
         input.
 
         Parameters
         ----------
         source : str, optional
 
             The source to execute. If not specified, the input buffer will be
             used. If specified and 'hidden' is False, the input buffer will be
             replaced with the source before execution.
 
         hidden : bool, optional (default False)
 
             If set, no output will be shown and the prompt will not be modified.
             In other words, it will be completely invisible to the user that
             an execution has occurred.
 
         interactive : bool, optional (default False)
 
             Whether the console is to treat the source as having been manually
             entered by the user. The effect of this parameter depends on the
             subclass implementation.
 
         Raises
         ------
         RuntimeError
             If incomplete input is given and 'hidden' is True. In this case,
             it is not possible to prompt for more input.
 
         Returns
         -------
         A boolean indicating whether the source was executed.
         """
         # WARNING: The order in which things happen here is very particular, in
         # large part because our syntax highlighting is fragile. If you change
         # something, test carefully!
 
         # Decide what to execute.
         if source is None:
             source = self.input_buffer
             if not hidden:
                 # A newline is appended later, but it should be considered part
                 # of the input buffer.
                 source += '\n'
         elif not hidden:
             self.input_buffer = source
 
         # Execute the source or show a continuation prompt if it is incomplete.
         if self.execute_on_complete_input:
             complete = self._is_complete(source, interactive)
         else:
             complete = not interactive
         if hidden:
             if complete or not self.execute_on_complete_input:
                 self._execute(source, hidden)
             else:
                 error = 'Incomplete noninteractive input: "%s"'
                 raise RuntimeError(error % source)
         else:
             if complete:
                 self._append_plain_text('\n')
                 self._input_buffer_executing = self.input_buffer
                 self._executing = True
                 self._prompt_finished()
 
                 # The maximum block count is only in effect during execution.
                 # This ensures that _prompt_pos does not become invalid due to
                 # text truncation.
                 self._control.document().setMaximumBlockCount(self.buffer_size)
 
                 # Setting a positive maximum block count will automatically
                 # disable the undo/redo history, but just to be safe:
                 self._control.setUndoRedoEnabled(False)
 
                 # Perform actual execution.
                 self._execute(source, hidden)
 
             else:
                 # Do this inside an edit block so continuation prompts are
                 # removed seamlessly via undo/redo.
                 cursor = self._get_end_cursor()
                 cursor.beginEditBlock()
                 cursor.insertText('\n')
                 self._insert_continuation_prompt(cursor)
                 cursor.endEditBlock()
 
                 # Do not do this inside the edit block. It works as expected
                 # when using a QPlainTextEdit control, but does not have an
                 # effect when using a QTextEdit. I believe this is a Qt bug.
                 self._control.moveCursor(QtGui.QTextCursor.End)
 
         return complete
 
     def export_html(self):
         """ Shows a dialog to export HTML/XML in various formats.
         """
         self._html_exporter.export()
 
     def _get_input_buffer(self, force=False):
         """ The text that the user has entered entered at the current prompt.
 
         If the console is currently executing, the text that is executing will
         always be returned.
         """
         # If we're executing, the input buffer may not even exist anymore due to
         # the limit imposed by 'buffer_size'. Therefore, we store it.
         if self._executing and not force:
             return self._input_buffer_executing
 
         cursor = self._get_end_cursor()
         cursor.setPosition(self._prompt_pos, QtGui.QTextCursor.KeepAnchor)
         input_buffer = cursor.selection().toPlainText()
 
         # Strip out continuation prompts.
         return input_buffer.replace('\n' + self._continuation_prompt, '\n')
 
     def _set_input_buffer(self, string):
         """ Sets the text in the input buffer.
 
         If the console is currently executing, this call has no *immediate*
         effect. When the execution is finished, the input buffer will be updated
         appropriately.
         """
         # If we're executing, store the text for later.
         if self._executing:
             self._input_buffer_pending = string
             return
 
         # Remove old text.
         cursor = self._get_end_cursor()
         cursor.beginEditBlock()
         cursor.setPosition(self._prompt_pos, QtGui.QTextCursor.KeepAnchor)
         cursor.removeSelectedText()
 
         # Insert new text with continuation prompts.
         self._insert_plain_text_into_buffer(self._get_prompt_cursor(), string)
         cursor.endEditBlock()
         self._control.moveCursor(QtGui.QTextCursor.End)
 
     input_buffer = property(_get_input_buffer, _set_input_buffer)
 
     def _get_font(self):
         """ The base font being used by the ConsoleWidget.
         """
         return self._control.document().defaultFont()
 
     def _set_font(self, font):
         """ Sets the base font for the ConsoleWidget to the specified QFont.
         """
         font_metrics = QtGui.QFontMetrics(font)
         self._control.setTabStopWidth(self.tab_width * font_metrics.width(' '))
 
         self._completion_widget.setFont(font)
         self._control.document().setDefaultFont(font)
         if self._page_control:
             self._page_control.document().setDefaultFont(font)
 
         self.font_changed.emit(font)
 
     font = property(_get_font, _set_font)
 
     def open_anchor(self, anchor):
         """ Open selected anchor in the default webbrowser
         """
         webbrowser.open( anchor )
 
     def paste(self, mode=QtGui.QClipboard.Clipboard):
         """ Paste the contents of the clipboard into the input region.
 
         Parameters
         ----------
         mode : QClipboard::Mode, optional [default QClipboard::Clipboard]
 
             Controls which part of the system clipboard is used. This can be
             used to access the selection clipboard in X11 and the Find buffer
             in Mac OS. By default, the regular clipboard is used.
         """
         if self._control.textInteractionFlags() & QtCore.Qt.TextEditable:
             # Make sure the paste is safe.
             self._keep_cursor_in_buffer()
             cursor = self._control.textCursor()
 
             # Remove any trailing newline, which confuses the GUI and forces the
             # user to backspace.
             text = QtGui.QApplication.clipboard().text(mode).rstrip()
             self._insert_plain_text_into_buffer(cursor, dedent(text))
 
     def print_(self, printer = None):
         """ Print the contents of the ConsoleWidget to the specified QPrinter.
         """
         if (not printer):
             printer = QtGui.QPrinter()
             if(QtGui.QPrintDialog(printer).exec_() != QtGui.QDialog.Accepted):
                 return
         self._control.print_(printer)
 
     def prompt_to_top(self):
         """ Moves the prompt to the top of the viewport.
         """
         if not self._executing:
             prompt_cursor = self._get_prompt_cursor()
             if self._get_cursor().blockNumber() < prompt_cursor.blockNumber():
                 self._set_cursor(prompt_cursor)
             self._set_top_cursor(prompt_cursor)
 
     def redo(self):
         """ Redo the last operation. If there is no operation to redo, nothing
             happens.
         """
         self._control.redo()
 
     def reset_font(self):
         """ Sets the font to the default fixed-width font for this platform.
         """
         if sys.platform == 'win32':
             # Consolas ships with Vista/Win7, fallback to Courier if needed
             fallback = 'Courier'
         elif sys.platform == 'darwin':
             # OSX always has Monaco
             fallback = 'Monaco'
         else:
             # Monospace should always exist
             fallback = 'Monospace'
         font = get_font(self.font_family, fallback)
         if self.font_size:
             font.setPointSize(self.font_size)
         else:
             font.setPointSize(QtGui.qApp.font().pointSize())
         font.setStyleHint(QtGui.QFont.TypeWriter)
         self._set_font(font)
 
     def change_font_size(self, delta):
         """Change the font size by the specified amount (in points).
         """
         font = self.font
         size = max(font.pointSize() + delta, 1) # minimum 1 point
         font.setPointSize(size)
         self._set_font(font)
 
     def _increase_font_size(self):
         self.change_font_size(1)
 
     def _decrease_font_size(self):
         self.change_font_size(-1)
 
     def select_all(self):
         """ Selects all the text in the buffer.
         """
         self._control.selectAll()
 
     def _get_tab_width(self):
         """ The width (in terms of space characters) for tab characters.
         """
         return self._tab_width
 
     def _set_tab_width(self, tab_width):
         """ Sets the width (in terms of space characters) for tab characters.
         """
         font_metrics = QtGui.QFontMetrics(self.font)
         self._control.setTabStopWidth(tab_width * font_metrics.width(' '))
 
         self._tab_width = tab_width
 
     tab_width = property(_get_tab_width, _set_tab_width)
 
     def undo(self):
         """ Undo the last operation. If there is no operation to undo, nothing
             happens.
         """
         self._control.undo()
 
     #---------------------------------------------------------------------------
     # 'ConsoleWidget' abstract interface
     #---------------------------------------------------------------------------
 
     def _is_complete(self, source, interactive):
         """ Returns whether 'source' can be executed. When triggered by an
             Enter/Return key press, 'interactive' is True; otherwise, it is
             False.
         """
         raise NotImplementedError
 
     def _execute(self, source, hidden):
         """ Execute 'source'. If 'hidden', do not show any output.
         """
         raise NotImplementedError
 
     def _prompt_started_hook(self):
         """ Called immediately after a new prompt is displayed.
         """
         pass
 
     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.
         """
         pass
 
     def _up_pressed(self, shift_modifier):
         """ Called when the up key is pressed. Returns whether to continue
             processing the event.
         """
         return True
 
     def _down_pressed(self, shift_modifier):
         """ Called when the down key is pressed. Returns whether to continue
             processing the event.
         """
         return True
 
     def _tab_pressed(self):
         """ Called when the tab key is pressed. Returns whether to continue
             processing the event.
         """
         return False
 
     #--------------------------------------------------------------------------
     # 'ConsoleWidget' protected interface
     #--------------------------------------------------------------------------
 
     def _append_custom(self, insert, input, before_prompt=False, *args, **kwargs):
         """ A low-level method for appending content to the end of the buffer.
 
         If 'before_prompt' is enabled, the content will be inserted before the
         current prompt, if there is one.
         """
         # Determine where to insert the content.
         cursor = self._control.textCursor()
         if before_prompt and (self._reading or not self._executing):
             self._flush_pending_stream()
             cursor.setPosition(self._append_before_prompt_pos)
         else:
             if insert != self._insert_plain_text:
                 self._flush_pending_stream()
             cursor.movePosition(QtGui.QTextCursor.End)
         start_pos = cursor.position()
 
         # Perform the insertion.
         result = insert(cursor, input, *args, **kwargs)
 
         # Adjust the prompt position if we have inserted before it. This is safe
         # because buffer truncation is disabled when not executing.
         if before_prompt and (self._reading or not self._executing):
             diff = cursor.position() - start_pos
             self._append_before_prompt_pos += diff
             self._prompt_pos += diff
 
         return result
 
     def _append_block(self, block_format=None, before_prompt=False):
         """ Appends an new QTextBlock to the end of the console buffer.
         """
         self._append_custom(self._insert_block, block_format, before_prompt)
 
     def _append_html(self, html, before_prompt=False):
         """ Appends HTML at the end of the console buffer.
         """
         self._append_custom(self._insert_html, html, before_prompt)
 
     def _append_html_fetching_plain_text(self, html, before_prompt=False):
         """ Appends HTML, then returns the plain text version of it.
         """
         return self._append_custom(self._insert_html_fetching_plain_text,
                                    html, before_prompt)
 
     def _append_plain_text(self, text, before_prompt=False):
         """ Appends plain text, processing ANSI codes if enabled.
         """
         self._append_custom(self._insert_plain_text, text, before_prompt)
 
     def _cancel_completion(self):
         """ If text completion is progress, cancel it.
         """
         self._completion_widget.cancel_completion()
 
     def _clear_temporary_buffer(self):
         """ Clears the "temporary text" buffer, i.e. all the text following
             the prompt region.
         """
         # Select and remove all text below the input buffer.
         cursor = self._get_prompt_cursor()
         prompt = self._continuation_prompt.lstrip()
         if(self._temp_buffer_filled):
             self._temp_buffer_filled = False
             while cursor.movePosition(QtGui.QTextCursor.NextBlock):
                 temp_cursor = QtGui.QTextCursor(cursor)
                 temp_cursor.select(QtGui.QTextCursor.BlockUnderCursor)
                 text = temp_cursor.selection().toPlainText().lstrip()
                 if not text.startswith(prompt):
                     break
         else:
             # We've reached the end of the input buffer and no text follows.
             return
         cursor.movePosition(QtGui.QTextCursor.Left) # Grab the newline.
         cursor.movePosition(QtGui.QTextCursor.End,
                             QtGui.QTextCursor.KeepAnchor)
         cursor.removeSelectedText()
 
         # After doing this, we have no choice but to clear the undo/redo
         # history. Otherwise, the text is not "temporary" at all, because it
         # can be recalled with undo/redo. Unfortunately, Qt does not expose
         # fine-grained control to the undo/redo system.
         if self._control.isUndoRedoEnabled():
             self._control.setUndoRedoEnabled(False)
             self._control.setUndoRedoEnabled(True)
 
     def _complete_with_items(self, cursor, items):
         """ Performs completion with 'items' at the specified cursor location.
         """
         self._cancel_completion()
 
         if len(items) == 1:
             cursor.setPosition(self._control.textCursor().position(),
                                QtGui.QTextCursor.KeepAnchor)
             cursor.insertText(items[0])
 
         elif len(items) > 1:
             current_pos = self._control.textCursor().position()
             prefix = commonprefix(items)
             if prefix:
                 cursor.setPosition(current_pos, QtGui.QTextCursor.KeepAnchor)
                 cursor.insertText(prefix)
                 current_pos = cursor.position()
 
             cursor.movePosition(QtGui.QTextCursor.Left, n=len(prefix))
             self._completion_widget.show_items(cursor, items)
 
 
     def _fill_temporary_buffer(self, cursor, text, html=False):
         """fill the area below the active editting zone with text"""
 
         current_pos = self._control.textCursor().position()
 
         cursor.beginEditBlock()
         self._append_plain_text('\n')
         self._page(text, html=html)
         cursor.endEditBlock()
 
         cursor.setPosition(current_pos)
         self._control.moveCursor(QtGui.QTextCursor.End)
         self._control.setTextCursor(cursor)
 
         self._temp_buffer_filled = True
 
 
     def _context_menu_make(self, pos):
         """ Creates a context menu for the given QPoint (in widget coordinates).
         """
         menu = QtGui.QMenu(self)
 
         self.cut_action = menu.addAction('Cut', self.cut)
         self.cut_action.setEnabled(self.can_cut())
         self.cut_action.setShortcut(QtGui.QKeySequence.Cut)
 
         self.copy_action = menu.addAction('Copy', self.copy)
         self.copy_action.setEnabled(self.can_copy())
         self.copy_action.setShortcut(QtGui.QKeySequence.Copy)
 
         self.paste_action = menu.addAction('Paste', self.paste)
         self.paste_action.setEnabled(self.can_paste())
         self.paste_action.setShortcut(QtGui.QKeySequence.Paste)
 
         anchor = self._control.anchorAt(pos)
         if anchor:
             menu.addSeparator()
             self.copy_link_action = menu.addAction(
                 'Copy Link Address', lambda: self.copy_anchor(anchor=anchor))
             self.open_link_action = menu.addAction(
                 'Open Link', lambda: self.open_anchor(anchor=anchor))
 
         menu.addSeparator()
         menu.addAction(self.select_all_action)
 
         menu.addSeparator()
         menu.addAction(self.export_action)
         menu.addAction(self.print_action)
 
         return menu
 
     def _control_key_down(self, modifiers, include_command=False):
         """ Given a KeyboardModifiers flags object, return whether the Control
         key is down.
 
         Parameters
         ----------
         include_command : bool, optional (default True)
             Whether to treat the Command key as a (mutually exclusive) synonym
             for Control when in Mac OS.
         """
         # Note that on Mac OS, ControlModifier corresponds to the Command key
         # while MetaModifier corresponds to the Control key.
         if sys.platform == 'darwin':
             down = include_command and (modifiers & QtCore.Qt.ControlModifier)
             return bool(down) ^ bool(modifiers & QtCore.Qt.MetaModifier)
         else:
             return bool(modifiers & QtCore.Qt.ControlModifier)
 
     def _create_control(self):
         """ Creates and connects the underlying text widget.
         """
         # Create the underlying control.
         if self.custom_control:
             control = self.custom_control()
         elif self.kind == 'plain':
             control = QtGui.QPlainTextEdit()
         elif self.kind == 'rich':
             control = QtGui.QTextEdit()
             control.setAcceptRichText(False)
             control.setMouseTracking(True)
 
         # Prevent the widget from handling drops, as we already provide
         # the logic in this class.
         control.setAcceptDrops(False)
 
         # Install event filters. The filter on the viewport is needed for
         # mouse events.
         control.installEventFilter(self)
         control.viewport().installEventFilter(self)
 
         # Connect signals.
         control.customContextMenuRequested.connect(
             self._custom_context_menu_requested)
         control.copyAvailable.connect(self.copy_available)
         control.redoAvailable.connect(self.redo_available)
         control.undoAvailable.connect(self.undo_available)
 
         # Hijack the document size change signal to prevent Qt from adjusting
         # the viewport's scrollbar. We are relying on an implementation detail
         # of Q(Plain)TextEdit here, which is potentially dangerous, but without
         # this functionality we cannot create a nice terminal interface.
         layout = control.document().documentLayout()
         layout.documentSizeChanged.disconnect()
         layout.documentSizeChanged.connect(self._adjust_scrollbars)
 
         # Configure the control.
         control.setAttribute(QtCore.Qt.WA_InputMethodEnabled, True)
         control.setContextMenuPolicy(QtCore.Qt.CustomContextMenu)
         control.setReadOnly(True)
         control.setUndoRedoEnabled(False)
         control.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
         return control
 
     def _create_page_control(self):
         """ Creates and connects the underlying paging widget.
         """
         if self.custom_page_control:
             control = self.custom_page_control()
         elif self.kind == 'plain':
             control = QtGui.QPlainTextEdit()
         elif self.kind == 'rich':
             control = QtGui.QTextEdit()
         control.installEventFilter(self)
         viewport = control.viewport()
         viewport.installEventFilter(self)
         control.setReadOnly(True)
         control.setUndoRedoEnabled(False)
         control.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
         return control
 
     def _event_filter_console_keypress(self, event):
         """ Filter key events for the underlying text widget to create a
             console-like interface.
         """
         intercepted = False
         cursor = self._control.textCursor()
         position = cursor.position()
         key = event.key()
         ctrl_down = self._control_key_down(event.modifiers())
         alt_down = event.modifiers() & QtCore.Qt.AltModifier
         shift_down = event.modifiers() & QtCore.Qt.ShiftModifier
 
         #------ Special sequences ----------------------------------------------
 
         if event.matches(QtGui.QKeySequence.Copy):
             self.copy()
             intercepted = True
 
         elif event.matches(QtGui.QKeySequence.Cut):
             self.cut()
             intercepted = True
 
         elif event.matches(QtGui.QKeySequence.Paste):
             self.paste()
             intercepted = True
 
         #------ Special modifier logic -----------------------------------------
 
         elif key in (QtCore.Qt.Key_Return, QtCore.Qt.Key_Enter):
             intercepted = True
 
             # Special handling when tab completing in text mode.
             self._cancel_completion()
 
             if self._in_buffer(position):
                 # Special handling when a reading a line of raw input.
                 if self._reading:
                     self._append_plain_text('\n')
                     self._reading = False
                     if self._reading_callback:
                         self._reading_callback()
 
                 # If the input buffer is a single line or there is only
                 # whitespace after the cursor, execute. Otherwise, split the
                 # line with a continuation prompt.
                 elif not self._executing:
                     cursor.movePosition(QtGui.QTextCursor.End,
                                         QtGui.QTextCursor.KeepAnchor)
                     at_end = len(cursor.selectedText().strip()) == 0
                     single_line = (self._get_end_cursor().blockNumber() ==
                                    self._get_prompt_cursor().blockNumber())
                     if (at_end or shift_down or single_line) and not ctrl_down:
                         self.execute(interactive = not shift_down)
                     else:
                         # Do this inside an edit block for clean undo/redo.
                         cursor.beginEditBlock()
                         cursor.setPosition(position)
                         cursor.insertText('\n')
                         self._insert_continuation_prompt(cursor)
                         cursor.endEditBlock()
 
                         # Ensure that the whole input buffer is visible.
                         # FIXME: This will not be usable if the input buffer is
                         # taller than the console widget.
                         self._control.moveCursor(QtGui.QTextCursor.End)
                         self._control.setTextCursor(cursor)
 
         #------ Control/Cmd modifier -------------------------------------------
 
         elif ctrl_down:
             if key == QtCore.Qt.Key_G:
                 self._keyboard_quit()
                 intercepted = True
 
             elif key == QtCore.Qt.Key_K:
                 if self._in_buffer(position):
                     cursor.clearSelection()
                     cursor.movePosition(QtGui.QTextCursor.EndOfLine,
                                         QtGui.QTextCursor.KeepAnchor)
                     if not cursor.hasSelection():
                         # Line deletion (remove continuation prompt)
                         cursor.movePosition(QtGui.QTextCursor.NextBlock,
                                             QtGui.QTextCursor.KeepAnchor)
                         cursor.movePosition(QtGui.QTextCursor.Right,
                                             QtGui.QTextCursor.KeepAnchor,
                                             len(self._continuation_prompt))
                     self._kill_ring.kill_cursor(cursor)
                     self._set_cursor(cursor)
                 intercepted = True
 
             elif key == QtCore.Qt.Key_L:
                 self.prompt_to_top()
                 intercepted = True
 
             elif key == QtCore.Qt.Key_O:
                 if self._page_control and self._page_control.isVisible():
                     self._page_control.setFocus()
                 intercepted = True
 
             elif key == QtCore.Qt.Key_U:
                 if self._in_buffer(position):
                     cursor.clearSelection()
                     start_line = cursor.blockNumber()
                     if start_line == self._get_prompt_cursor().blockNumber():
                         offset = len(self._prompt)
                     else:
                         offset = len(self._continuation_prompt)
                     cursor.movePosition(QtGui.QTextCursor.StartOfBlock,
                                         QtGui.QTextCursor.KeepAnchor)
                     cursor.movePosition(QtGui.QTextCursor.Right,
                                         QtGui.QTextCursor.KeepAnchor, offset)
                     self._kill_ring.kill_cursor(cursor)
                     self._set_cursor(cursor)
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Y:
                 self._keep_cursor_in_buffer()
                 self._kill_ring.yank()
                 intercepted = True
 
             elif key in (QtCore.Qt.Key_Backspace, QtCore.Qt.Key_Delete):
                 if key == QtCore.Qt.Key_Backspace:
                     cursor = self._get_word_start_cursor(position)
                 else: # key == QtCore.Qt.Key_Delete
                     cursor = self._get_word_end_cursor(position)
                 cursor.setPosition(position, QtGui.QTextCursor.KeepAnchor)
                 self._kill_ring.kill_cursor(cursor)
                 intercepted = True
 
             elif key == QtCore.Qt.Key_D:
                 if len(self.input_buffer) == 0:
                     self.exit_requested.emit(self)
                 else:
                     new_event = QtGui.QKeyEvent(QtCore.QEvent.KeyPress,
                                                 QtCore.Qt.Key_Delete,
                                                 QtCore.Qt.NoModifier)
                     QtGui.qApp.sendEvent(self._control, new_event)
                     intercepted = True
 
         #------ Alt modifier ---------------------------------------------------
 
         elif alt_down:
             if key == QtCore.Qt.Key_B:
                 self._set_cursor(self._get_word_start_cursor(position))
                 intercepted = True
 
             elif key == QtCore.Qt.Key_F:
                 self._set_cursor(self._get_word_end_cursor(position))
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Y:
                 self._kill_ring.rotate()
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Backspace:
                 cursor = self._get_word_start_cursor(position)
                 cursor.setPosition(position, QtGui.QTextCursor.KeepAnchor)
                 self._kill_ring.kill_cursor(cursor)
                 intercepted = True
 
             elif key == QtCore.Qt.Key_D:
                 cursor = self._get_word_end_cursor(position)
                 cursor.setPosition(position, QtGui.QTextCursor.KeepAnchor)
                 self._kill_ring.kill_cursor(cursor)
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Delete:
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Greater:
                 self._control.moveCursor(QtGui.QTextCursor.End)
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Less:
                 self._control.setTextCursor(self._get_prompt_cursor())
                 intercepted = True
 
         #------ No modifiers ---------------------------------------------------
 
         else:
             if shift_down:
                 anchormode = QtGui.QTextCursor.KeepAnchor
             else:
                 anchormode = QtGui.QTextCursor.MoveAnchor
 
             if key == QtCore.Qt.Key_Escape:
                 self._keyboard_quit()
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Up:
                 if self._reading or not self._up_pressed(shift_down):
                     intercepted = True
                 else:
                     prompt_line = self._get_prompt_cursor().blockNumber()
                     intercepted = cursor.blockNumber() <= prompt_line
 
             elif key == QtCore.Qt.Key_Down:
                 if self._reading or not self._down_pressed(shift_down):
                     intercepted = True
                 else:
                     end_line = self._get_end_cursor().blockNumber()
                     intercepted = cursor.blockNumber() == end_line
 
             elif key == QtCore.Qt.Key_Tab:
                 if not self._reading:
                     if self._tab_pressed():
                         # real tab-key, insert four spaces
                         cursor.insertText(' '*4)
                     intercepted = True
 
             elif key == QtCore.Qt.Key_Left:
 
                 # Move to the previous line
                 line, col = cursor.blockNumber(), cursor.columnNumber()
                 if line > self._get_prompt_cursor().blockNumber() and \
                         col == len(self._continuation_prompt):
                     self._control.moveCursor(QtGui.QTextCursor.PreviousBlock,
                                              mode=anchormode)
                     self._control.moveCursor(QtGui.QTextCursor.EndOfBlock,
                                              mode=anchormode)
                     intercepted = True
 
                 # Regular left movement
                 else:
                     intercepted = not self._in_buffer(position - 1)
 
             elif key == QtCore.Qt.Key_Right:
                 original_block_number = cursor.blockNumber()
                 self._control.moveCursor(QtGui.QTextCursor.Right,
                                 mode=anchormode)
                 if cursor.blockNumber() != original_block_number:
                     self._control.moveCursor(QtGui.QTextCursor.Right,
                                         n=len(self._continuation_prompt),
                                         mode=anchormode)
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Home:
                 start_line = cursor.blockNumber()
                 if start_line == self._get_prompt_cursor().blockNumber():
                     start_pos = self._prompt_pos
                 else:
                     cursor.movePosition(QtGui.QTextCursor.StartOfBlock,
                                         QtGui.QTextCursor.KeepAnchor)
                     start_pos = cursor.position()
                     start_pos += len(self._continuation_prompt)
                     cursor.setPosition(position)
                 if shift_down and self._in_buffer(position):
                     cursor.setPosition(start_pos, QtGui.QTextCursor.KeepAnchor)
                 else:
                     cursor.setPosition(start_pos)
                 self._set_cursor(cursor)
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Backspace:
 
                 # Line deletion (remove continuation prompt)
                 line, col = cursor.blockNumber(), cursor.columnNumber()
                 if not self._reading and \
                         col == len(self._continuation_prompt) and \
                         line > self._get_prompt_cursor().blockNumber():
                     cursor.beginEditBlock()
                     cursor.movePosition(QtGui.QTextCursor.StartOfBlock,
                                         QtGui.QTextCursor.KeepAnchor)
                     cursor.removeSelectedText()
                     cursor.deletePreviousChar()
                     cursor.endEditBlock()
                     intercepted = True
 
                 # Regular backwards deletion
                 else:
                     anchor = cursor.anchor()
                     if anchor == position:
                         intercepted = not self._in_buffer(position - 1)
                     else:
                         intercepted = not self._in_buffer(min(anchor, position))
 
             elif key == QtCore.Qt.Key_Delete:
 
                 # Line deletion (remove continuation prompt)
                 if not self._reading and self._in_buffer(position) and \
                         cursor.atBlockEnd() and not cursor.hasSelection():
                     cursor.movePosition(QtGui.QTextCursor.NextBlock,
                                         QtGui.QTextCursor.KeepAnchor)
                     cursor.movePosition(QtGui.QTextCursor.Right,
                                         QtGui.QTextCursor.KeepAnchor,
                                         len(self._continuation_prompt))
                     cursor.removeSelectedText()
                     intercepted = True
 
                 # Regular forwards deletion:
                 else:
                     anchor = cursor.anchor()
                     intercepted = (not self._in_buffer(anchor) or
                                    not self._in_buffer(position))
 
         # Don't move the cursor if Control/Cmd is pressed to allow copy-paste
         # using the keyboard in any part of the buffer. Also, permit scrolling
         # with Page Up/Down keys. Finally, if we're executing, don't move the
         # cursor (if even this made sense, we can't guarantee that the prompt
         # position is still valid due to text truncation).
         if not (self._control_key_down(event.modifiers(), include_command=True)
                 or key in (QtCore.Qt.Key_PageUp, QtCore.Qt.Key_PageDown)
                 or (self._executing and not self._reading)):
             self._keep_cursor_in_buffer()
 
         return intercepted
 
     def _event_filter_page_keypress(self, event):
         """ Filter key events for the paging widget to create console-like
             interface.
         """
         key = event.key()
         ctrl_down = self._control_key_down(event.modifiers())
         alt_down = event.modifiers() & QtCore.Qt.AltModifier
 
         if ctrl_down:
             if key == QtCore.Qt.Key_O:
                 self._control.setFocus()
                 intercept = True
 
         elif alt_down:
             if key == QtCore.Qt.Key_Greater:
                 self._page_control.moveCursor(QtGui.QTextCursor.End)
                 intercepted = True
 
             elif key == QtCore.Qt.Key_Less:
                 self._page_control.moveCursor(QtGui.QTextCursor.Start)
                 intercepted = True
 
         elif key in (QtCore.Qt.Key_Q, QtCore.Qt.Key_Escape):
             if self._splitter:
                 self._page_control.hide()
                 self._control.setFocus()
             else:
                 self.layout().setCurrentWidget(self._control)
                 # re-enable buffer truncation after paging
                 self._control.document().setMaximumBlockCount(self.buffer_size)
             return True
 
         elif key in (QtCore.Qt.Key_Enter, QtCore.Qt.Key_Return,
                      QtCore.Qt.Key_Tab):
             new_event = QtGui.QKeyEvent(QtCore.QEvent.KeyPress,
                                         QtCore.Qt.Key_PageDown,
                                         QtCore.Qt.NoModifier)
             QtGui.qApp.sendEvent(self._page_control, new_event)
             return True
 
         elif key == QtCore.Qt.Key_Backspace:
             new_event = QtGui.QKeyEvent(QtCore.QEvent.KeyPress,
                                         QtCore.Qt.Key_PageUp,
                                         QtCore.Qt.NoModifier)
             QtGui.qApp.sendEvent(self._page_control, new_event)
             return True
 
         # vi/less -like key bindings
         elif key == QtCore.Qt.Key_J:
             new_event = QtGui.QKeyEvent(QtCore.QEvent.KeyPress,
                                         QtCore.Qt.Key_Down,
                                         QtCore.Qt.NoModifier)
             QtGui.qApp.sendEvent(self._page_control, new_event)
             return True
 
         # vi/less -like key bindings
         elif key == QtCore.Qt.Key_K:
             new_event = QtGui.QKeyEvent(QtCore.QEvent.KeyPress,
                                         QtCore.Qt.Key_Up,
                                         QtCore.Qt.NoModifier)
             QtGui.qApp.sendEvent(self._page_control, new_event)
             return True
 
         return False
 
     def _on_flush_pending_stream_timer(self):
         """ Flush the pending stream output and change the
         prompt position appropriately.
         """
         cursor = self._control.textCursor()
         cursor.movePosition(QtGui.QTextCursor.End)
         pos = cursor.position()
         self._flush_pending_stream()
         cursor.movePosition(QtGui.QTextCursor.End)
         diff = cursor.position() - pos
         if diff > 0:
             self._prompt_pos += diff
             self._append_before_prompt_pos += diff
 
     def _flush_pending_stream(self):
         """ Flush out pending text into the widget. """
         text = self._pending_insert_text
         self._pending_insert_text = []
         buffer_size = self._control.document().maximumBlockCount()
         if buffer_size > 0:
             text = self._get_last_lines_from_list(text, buffer_size)
         text = ''.join(text)
         t = time.time()
         self._insert_plain_text(self._get_end_cursor(), text, flush=True)
         # Set the flush interval to equal the maximum time to update text.
         self._pending_text_flush_interval.setInterval(max(100,
                                                  (time.time()-t)*1000))
 
     def _format_as_columns(self, items, separator='  '):
         """ Transform a list of strings into a single string with columns.
 
         Parameters
         ----------
         items : sequence of strings
             The strings to process.
 
         separator : str, optional [default is two spaces]
             The string that separates columns.
 
         Returns
         -------
         The formatted string.
         """
         # Calculate the number of characters available.
         width = self._control.viewport().width()
         char_width = QtGui.QFontMetrics(self.font).width(' ')
         displaywidth = max(10, (width / char_width) - 1)
 
         return columnize(items, separator, displaywidth)
 
     def _get_block_plain_text(self, block):
         """ Given a QTextBlock, return its unformatted text.
         """
         cursor = QtGui.QTextCursor(block)
         cursor.movePosition(QtGui.QTextCursor.StartOfBlock)
         cursor.movePosition(QtGui.QTextCursor.EndOfBlock,
                             QtGui.QTextCursor.KeepAnchor)
         return cursor.selection().toPlainText()
 
     def _get_cursor(self):
         """ Convenience method that returns a cursor for the current position.
         """
         return self._control.textCursor()
 
     def _get_end_cursor(self):
         """ Convenience method that returns a cursor for the last character.
         """
         cursor = self._control.textCursor()
         cursor.movePosition(QtGui.QTextCursor.End)
         return cursor
 
     def _get_input_buffer_cursor_column(self):
         """ Returns the column of the cursor in the input buffer, excluding the
             contribution by the prompt, or -1 if there is no such column.
         """
         prompt = self._get_input_buffer_cursor_prompt()
         if prompt is None:
             return -1
         else:
             cursor = self._control.textCursor()
             return cursor.columnNumber() - len(prompt)
 
     def _get_input_buffer_cursor_line(self):
         """ Returns the text of the line of the input buffer that contains the
             cursor, or None if there is no such line.
         """
         prompt = self._get_input_buffer_cursor_prompt()
         if prompt is None:
             return None
         else:
             cursor = self._control.textCursor()
             text = self._get_block_plain_text(cursor.block())
             return text[len(prompt):]
     
     def _get_input_buffer_cursor_pos(self):
         """Return the cursor position within the input buffer."""
         cursor = self._control.textCursor()
         cursor.setPosition(self._prompt_pos, QtGui.QTextCursor.KeepAnchor)
         input_buffer = cursor.selection().toPlainText()
         
         # Don't count continuation prompts
         return len(input_buffer.replace('\n' + self._continuation_prompt, '\n'))
     
     def _get_input_buffer_cursor_prompt(self):
         """ Returns the (plain text) prompt for line of the input buffer that
             contains the cursor, or None if there is no such line.
         """
         if self._executing:
             return None
         cursor = self._control.textCursor()
         if cursor.position() >= self._prompt_pos:
             if cursor.blockNumber() == self._get_prompt_cursor().blockNumber():
                 return self._prompt
             else:
                 return self._continuation_prompt
         else:
             return None
 
     def _get_last_lines(self, text, num_lines, return_count=False):
         """ Return last specified number of lines of text (like `tail -n`).
         If return_count is True, returns a tuple of clipped text and the
         number of lines in the clipped text.
         """
         pos = len(text)
         if pos < num_lines:
             if return_count:
                 return text, text.count('\n') if return_count else text
             else:
                 return text
         i = 0
         while i < num_lines:
             pos = text.rfind('\n', None, pos)
             if pos == -1:
                 pos = None
                 break
             i += 1
         if return_count:
             return text[pos:], i
         else:
             return text[pos:]
 
     def _get_last_lines_from_list(self, text_list, num_lines):
         """ Return the list of text clipped to last specified lines.
         """
         ret = []
         lines_pending = num_lines
         for text in reversed(text_list):
             text, lines_added = self._get_last_lines(text, lines_pending,
                                                      return_count=True)
             ret.append(text)
             lines_pending -= lines_added
             if lines_pending <= 0:
                 break
         return ret[::-1]
 
     def _get_prompt_cursor(self):
         """ Convenience method that returns a cursor for the prompt position.
         """
         cursor = self._control.textCursor()
         cursor.setPosition(self._prompt_pos)
         return cursor
 
     def _get_selection_cursor(self, start, end):
         """ Convenience method that returns a cursor with text selected between
             the positions 'start' and 'end'.
         """
         cursor = self._control.textCursor()
         cursor.setPosition(start)
         cursor.setPosition(end, QtGui.QTextCursor.KeepAnchor)
         return cursor
 
     def _get_word_start_cursor(self, position):
         """ Find the start of the word to the left the given position. If a
             sequence of non-word characters precedes the first word, skip over
             them. (This emulates the behavior of bash, emacs, etc.)
         """
         document = self._control.document()
         position -= 1
         while position >= self._prompt_pos and \
                   not is_letter_or_number(document.characterAt(position)):
             position -= 1
         while position >= self._prompt_pos and \
                   is_letter_or_number(document.characterAt(position)):
             position -= 1
         cursor = self._control.textCursor()
         cursor.setPosition(position + 1)
         return cursor
 
     def _get_word_end_cursor(self, position):
         """ Find the end of the word to the right the given position. If a
             sequence of non-word characters precedes the first word, skip over
             them. (This emulates the behavior of bash, emacs, etc.)
         """
         document = self._control.document()
         end = self._get_end_cursor().position()
         while position < end and \
                   not is_letter_or_number(document.characterAt(position)):
             position += 1
         while position < end and \
                   is_letter_or_number(document.characterAt(position)):
             position += 1
         cursor = self._control.textCursor()
         cursor.setPosition(position)
         return cursor
 
     def _insert_continuation_prompt(self, cursor):
         """ Inserts new continuation prompt using the specified cursor.
         """
         if self._continuation_prompt_html is None:
             self._insert_plain_text(cursor, self._continuation_prompt)
         else:
             self._continuation_prompt = self._insert_html_fetching_plain_text(
                 cursor, self._continuation_prompt_html)
 
     def _insert_block(self, cursor, block_format=None):
         """ Inserts an empty QTextBlock using the specified cursor.
         """
         if block_format is None:
             block_format = QtGui.QTextBlockFormat()
         cursor.insertBlock(block_format)
 
     def _insert_html(self, cursor, html):
         """ Inserts HTML using the specified cursor in such a way that future
             formatting is unaffected.
         """
         cursor.beginEditBlock()
         cursor.insertHtml(html)
 
         # After inserting HTML, the text document "remembers" it's in "html
         # mode", which means that subsequent calls adding plain text will result
         # in unwanted formatting, lost tab characters, etc. The following code
         # hacks around this behavior, which I consider to be a bug in Qt, by
         # (crudely) resetting the document's style state.
         cursor.movePosition(QtGui.QTextCursor.Left,
                             QtGui.QTextCursor.KeepAnchor)
         if cursor.selection().toPlainText() == ' ':
             cursor.removeSelectedText()
         else:
             cursor.movePosition(QtGui.QTextCursor.Right)
         cursor.insertText(' ', QtGui.QTextCharFormat())
         cursor.endEditBlock()
 
     def _insert_html_fetching_plain_text(self, cursor, html):
         """ Inserts HTML using the specified cursor, then returns its plain text
             version.
         """
         cursor.beginEditBlock()
         cursor.removeSelectedText()
 
         start = cursor.position()
         self._insert_html(cursor, html)
         end = cursor.position()
         cursor.setPosition(start, QtGui.QTextCursor.KeepAnchor)
         text = cursor.selection().toPlainText()
 
         cursor.setPosition(end)
         cursor.endEditBlock()
         return text
 
     def _insert_plain_text(self, cursor, text, flush=False):
         """ Inserts plain text using the specified cursor, processing ANSI codes
             if enabled.
         """
         # maximumBlockCount() can be different from self.buffer_size in
         # case input prompt is active.
         buffer_size = self._control.document().maximumBlockCount()
 
         if (self._executing and not flush and
                 self._pending_text_flush_interval.isActive() and
                 cursor.position() == self._get_end_cursor().position()):
             # Queue the text to insert in case it is being inserted at end
             self._pending_insert_text.append(text)
             if buffer_size > 0:
                 self._pending_insert_text = self._get_last_lines_from_list(
                                         self._pending_insert_text, buffer_size)
             return
 
         if self._executing and not self._pending_text_flush_interval.isActive():
             self._pending_text_flush_interval.start()
 
         # Clip the text to last `buffer_size` lines.
         if buffer_size > 0:
             text = self._get_last_lines(text, buffer_size)
 
         cursor.beginEditBlock()
         if self.ansi_codes:
             for substring in self._ansi_processor.split_string(text):
                 for act in self._ansi_processor.actions:
 
                     # Unlike real terminal emulators, we don't distinguish
                     # between the screen and the scrollback buffer. A screen
                     # erase request clears everything.
                     if act.action == 'erase' and act.area == 'screen':
                         cursor.select(QtGui.QTextCursor.Document)
                         cursor.removeSelectedText()
 
                     # Simulate a form feed by scrolling just past the last line.
                     elif act.action == 'scroll' and act.unit == 'page':
                         cursor.insertText('\n')
                         cursor.endEditBlock()
                         self._set_top_cursor(cursor)
                         cursor.joinPreviousEditBlock()
                         cursor.deletePreviousChar()
 
                     elif act.action == 'carriage-return':
                         cursor.movePosition(
                             cursor.StartOfLine, cursor.KeepAnchor)
 
                     elif act.action == 'beep':
                         QtGui.qApp.beep()
 
                     elif act.action == 'backspace':
                         if not cursor.atBlockStart():
                             cursor.movePosition(
                                 cursor.PreviousCharacter, cursor.KeepAnchor)
 
                     elif act.action == 'newline':
                         cursor.movePosition(cursor.EndOfLine)
 
                 format = self._ansi_processor.get_format()
 
                 selection = cursor.selectedText()
                 if len(selection) == 0:
                     cursor.insertText(substring, format)
                 elif substring is not None:
                     # BS and CR are treated as a change in print
                     # position, rather than a backwards character
                     # deletion for output equivalence with (I)Python
                     # terminal.
                     if len(substring) >= len(selection):
                         cursor.insertText(substring, format)
                     else:
                         old_text = selection[len(substring):]
                         cursor.insertText(substring + old_text, format)
                         cursor.movePosition(cursor.PreviousCharacter,
                                cursor.KeepAnchor, len(old_text))
         else:
             cursor.insertText(text)
         cursor.endEditBlock()
 
     def _insert_plain_text_into_buffer(self, cursor, text):
         """ Inserts text into the input buffer using the specified cursor (which
             must be in the input buffer), ensuring that continuation prompts are
             inserted as necessary.
         """
         lines = text.splitlines(True)
         if lines:
             cursor.beginEditBlock()
             cursor.insertText(lines[0])
             for line in lines[1:]:
                 if self._continuation_prompt_html is None:
                     cursor.insertText(self._continuation_prompt)
                 else:
                     self._continuation_prompt = \
                         self._insert_html_fetching_plain_text(
                             cursor, self._continuation_prompt_html)
                 cursor.insertText(line)
             cursor.endEditBlock()
 
     def _in_buffer(self, position=None):
         """ Returns whether the current cursor (or, if specified, a position) is
             inside the editing region.
         """
         cursor = self._control.textCursor()
         if position is None:
             position = cursor.position()
         else:
             cursor.setPosition(position)
         line = cursor.blockNumber()
         prompt_line = self._get_prompt_cursor().blockNumber()
         if line == prompt_line:
             return position >= self._prompt_pos
         elif line > prompt_line:
             cursor.movePosition(QtGui.QTextCursor.StartOfBlock)
             prompt_pos = cursor.position() + len(self._continuation_prompt)
             return position >= prompt_pos
         return False
 
     def _keep_cursor_in_buffer(self):
         """ Ensures that the cursor is inside the editing region. Returns
             whether the cursor was moved.
         """
         moved = not self._in_buffer()
         if moved:
             cursor = self._control.textCursor()
             cursor.movePosition(QtGui.QTextCursor.End)
             self._control.setTextCursor(cursor)
         return moved
 
     def _keyboard_quit(self):
         """ Cancels the current editing task ala Ctrl-G in Emacs.
         """
         if self._temp_buffer_filled :
             self._cancel_completion()
             self._clear_temporary_buffer()
         else:
             self.input_buffer = ''
 
     def _page(self, text, html=False):
         """ Displays text using the pager if it exceeds the height of the
         viewport.
 
         Parameters
         ----------
         html : bool, optional (default False)
             If set, the text will be interpreted as HTML instead of plain text.
         """
         line_height = QtGui.QFontMetrics(self.font).height()
         minlines = self._control.viewport().height() / line_height
         if self.paging != 'none' and \
                 re.match("(?:[^\n]*\n){%i}" % minlines, text):
             if self.paging == 'custom':
                 self.custom_page_requested.emit(text)
             else:
                 # disable buffer truncation during paging
                 self._control.document().setMaximumBlockCount(0)
                 self._page_control.clear()
                 cursor = self._page_control.textCursor()
                 if html:
                     self._insert_html(cursor, text)
                 else:
                     self._insert_plain_text(cursor, text)
                 self._page_control.moveCursor(QtGui.QTextCursor.Start)
 
                 self._page_control.viewport().resize(self._control.size())
                 if self._splitter:
                     self._page_control.show()
                     self._page_control.setFocus()
                 else:
                     self.layout().setCurrentWidget(self._page_control)
         elif html:
             self._append_html(text)
         else:
             self._append_plain_text(text)
 
     def _set_paging(self, paging):
         """
         Change the pager to `paging` style.
 
         Parameters
         ----------
         paging : string
             Either "hsplit", "vsplit", or "inside"
         """
         if self._splitter is None:
             raise NotImplementedError("""can only switch if --paging=hsplit or
                     --paging=vsplit is used.""")
         if paging == 'hsplit':
             self._splitter.setOrientation(QtCore.Qt.Horizontal)
         elif paging == 'vsplit':
             self._splitter.setOrientation(QtCore.Qt.Vertical)
         elif paging == 'inside':
             raise NotImplementedError("""switching to 'inside' paging not
                     supported yet.""")
         else:
             raise ValueError("unknown paging method '%s'" % paging)
         self.paging = paging
 
     def _prompt_finished(self):
         """ Called immediately after a prompt is finished, i.e. when some input
             will be processed and a new prompt displayed.
         """
         self._control.setReadOnly(True)
         self._prompt_finished_hook()
 
     def _prompt_started(self):
         """ Called immediately after a new prompt is displayed.
         """
         # Temporarily disable the maximum block count to permit undo/redo and
         # to ensure that the prompt position does not change due to truncation.
         self._control.document().setMaximumBlockCount(0)
         self._control.setUndoRedoEnabled(True)
 
         # Work around bug in QPlainTextEdit: input method is not re-enabled
         # when read-only is disabled.
         self._control.setReadOnly(False)
         self._control.setAttribute(QtCore.Qt.WA_InputMethodEnabled, True)
 
         if not self._reading:
             self._executing = False
         self._prompt_started_hook()
 
         # If the input buffer has changed while executing, load it.
         if self._input_buffer_pending:
             self.input_buffer = self._input_buffer_pending
             self._input_buffer_pending = ''
 
         self._control.moveCursor(QtGui.QTextCursor.End)
 
     def _readline(self, prompt='', callback=None):
         """ Reads one line of input from the user.
 
         Parameters
         ----------
         prompt : str, optional
             The prompt to print before reading the line.
 
         callback : callable, optional
             A callback to execute with the read line. If not specified, input is
             read *synchronously* and this method does not return until it has
             been read.
 
         Returns
         -------
         If a callback is specified, returns nothing. Otherwise, returns the
         input string with the trailing newline stripped.
         """
         if self._reading:
             raise RuntimeError('Cannot read a line. Widget is already reading.')
 
         if not callback and not self.isVisible():
             # If the user cannot see the widget, this function cannot return.
             raise RuntimeError('Cannot synchronously read a line if the widget '
                                'is not visible!')
 
         self._reading = True
         self._show_prompt(prompt, newline=False)
 
         if callback is None:
             self._reading_callback = None
             while self._reading:
                 QtCore.QCoreApplication.processEvents()
             return self._get_input_buffer(force=True).rstrip('\n')
 
         else:
             self._reading_callback = lambda: \
                 callback(self._get_input_buffer(force=True).rstrip('\n'))
 
     def _set_continuation_prompt(self, prompt, html=False):
         """ Sets the continuation prompt.
 
         Parameters
         ----------
         prompt : str
             The prompt to show when more input is needed.
 
         html : bool, optional (default False)
             If set, the prompt will be inserted as formatted HTML. Otherwise,
             the prompt will be treated as plain text, though ANSI color codes
             will be handled.
         """
         if html:
             self._continuation_prompt_html = prompt
         else:
             self._continuation_prompt = prompt
             self._continuation_prompt_html = None
 
     def _set_cursor(self, cursor):
         """ Convenience method to set the current cursor.
         """
         self._control.setTextCursor(cursor)
 
     def _set_top_cursor(self, cursor):
         """ Scrolls the viewport so that the specified cursor is at the top.
         """
         scrollbar = self._control.verticalScrollBar()
         scrollbar.setValue(scrollbar.maximum())
         original_cursor = self._control.textCursor()
         self._control.setTextCursor(cursor)
         self._control.ensureCursorVisible()
         self._control.setTextCursor(original_cursor)
 
     def _show_prompt(self, prompt=None, html=False, newline=True):
         """ Writes a new prompt at the end of the buffer.
 
         Parameters
         ----------
         prompt : str, optional
             The prompt to show. If not specified, the previous prompt is used.
 
         html : bool, optional (default False)
             Only relevant when a prompt is specified. If set, the prompt will
             be inserted as formatted HTML. Otherwise, the prompt will be treated
             as plain text, though ANSI color codes will be handled.
 
         newline : bool, optional (default True)
             If set, a new line will be written before showing the prompt if
             there is not already a newline at the end of the buffer.
         """
         # Save the current end position to support _append*(before_prompt=True).
         self._flush_pending_stream()
         cursor = self._get_end_cursor()
         self._append_before_prompt_pos = cursor.position()
 
         # Insert a preliminary newline, if necessary.
         if newline and cursor.position() > 0:
             cursor.movePosition(QtGui.QTextCursor.Left,
                                 QtGui.QTextCursor.KeepAnchor)
             if cursor.selection().toPlainText() != '\n':
                 self._append_block()
                 self._append_before_prompt_pos += 1
 
         # Write the prompt.
         self._append_plain_text(self._prompt_sep)
         if prompt is None:
             if self._prompt_html is None:
                 self._append_plain_text(self._prompt)
             else:
                 self._append_html(self._prompt_html)
         else:
             if html:
                 self._prompt = self._append_html_fetching_plain_text(prompt)
                 self._prompt_html = prompt
             else:
                 self._append_plain_text(prompt)
                 self._prompt = prompt
                 self._prompt_html = None
 
         self._flush_pending_stream()
         self._prompt_pos = self._get_end_cursor().position()
         self._prompt_started()
 
     #------ Signal handlers ----------------------------------------------------
 
     def _adjust_scrollbars(self):
         """ Expands the vertical scrollbar beyond the range set by Qt.
         """
         # This code is adapted from _q_adjustScrollbars in qplaintextedit.cpp
         # and qtextedit.cpp.
         document = self._control.document()
         scrollbar = self._control.verticalScrollBar()
         viewport_height = self._control.viewport().height()
         if isinstance(self._control, QtGui.QPlainTextEdit):
             maximum = max(0, document.lineCount() - 1)
             step = viewport_height / self._control.fontMetrics().lineSpacing()
         else:
             # QTextEdit does not do line-based layout and blocks will not in
             # general have the same height. Therefore it does not make sense to
             # attempt to scroll in line height increments.
             maximum = document.size().height()
             step = viewport_height
         diff = maximum - scrollbar.maximum()
         scrollbar.setRange(0, maximum)
         scrollbar.setPageStep(step)
 
         # Compensate for undesirable scrolling that occurs automatically due to
         # maximumBlockCount() text truncation.
         if diff < 0 and document.blockCount() == document.maximumBlockCount():
             scrollbar.setValue(scrollbar.value() + diff)
 
     def _custom_context_menu_requested(self, pos):
         """ Shows a context menu at the given QPoint (in widget coordinates).
         """
         menu = self._context_menu_make(pos)
         menu.exec_(self._control.mapToGlobal(pos))

IPython/qt/console/frontend_widget.py

@@ -1,824 +1,824 b''
 """Frontend widget for the Qt Console"""
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 from __future__ import print_function
 
 from collections import namedtuple
 import sys
 import uuid
 
 from IPython.external import qt
 from IPython.external.qt import QtCore, QtGui
 from IPython.utils import py3compat
 from IPython.utils.importstring import import_item
 
 from IPython.core.inputsplitter import InputSplitter, IPythonInputSplitter
 from IPython.core.inputtransformer import classic_prompt
 from IPython.core.oinspect import call_tip
 from IPython.qt.base_frontend_mixin import BaseFrontendMixin
 from IPython.utils.traitlets import Any, Bool, Instance, Unicode, DottedObjectName
 from .bracket_matcher import BracketMatcher
 from .call_tip_widget import CallTipWidget
 from .completion_lexer import CompletionLexer
 from .history_console_widget import HistoryConsoleWidget
 from .pygments_highlighter import PygmentsHighlighter
 
 
 class FrontendHighlighter(PygmentsHighlighter):
     """ A PygmentsHighlighter that understands and ignores prompts.
     """
 
     def __init__(self, frontend, lexer=None):
         super(FrontendHighlighter, self).__init__(frontend._control.document(), lexer=lexer)
         self._current_offset = 0
         self._frontend = frontend
         self.highlighting_on = False
 
     def highlightBlock(self, string):
         """ Highlight a block of text. Reimplemented to highlight selectively.
         """
         if not self.highlighting_on:
             return
 
         # The input to this function is a unicode string that may contain
         # paragraph break characters, non-breaking spaces, etc. Here we acquire
         # the string as plain text so we can compare it.
         current_block = self.currentBlock()
         string = self._frontend._get_block_plain_text(current_block)
 
         # Decide whether to check for the regular or continuation prompt.
         if current_block.contains(self._frontend._prompt_pos):
             prompt = self._frontend._prompt
         else:
             prompt = self._frontend._continuation_prompt
 
         # Only highlight if we can identify a prompt, but make sure not to
         # highlight the prompt.
         if string.startswith(prompt):
             self._current_offset = len(prompt)
             string = string[len(prompt):]
             super(FrontendHighlighter, self).highlightBlock(string)
 
     def rehighlightBlock(self, block):
         """ Reimplemented to temporarily enable highlighting if disabled.
         """
         old = self.highlighting_on
         self.highlighting_on = True
         super(FrontendHighlighter, self).rehighlightBlock(block)
         self.highlighting_on = old
 
     def setFormat(self, start, count, format):
         """ Reimplemented to highlight selectively.
         """
         start += self._current_offset
         super(FrontendHighlighter, self).setFormat(start, count, format)
 
 
 class FrontendWidget(HistoryConsoleWidget, BaseFrontendMixin):
     """ A Qt frontend for a generic Python kernel.
     """
 
     # The text to show when the kernel is (re)started.
     banner = Unicode(config=True)
     kernel_banner = Unicode()
 
     # An option and corresponding signal for overriding the default kernel
     # interrupt behavior.
     custom_interrupt = Bool(False)
     custom_interrupt_requested = QtCore.Signal()
 
     # An option and corresponding signals for overriding the default kernel
     # restart behavior.
     custom_restart = Bool(False)
     custom_restart_kernel_died = QtCore.Signal(float)
     custom_restart_requested = QtCore.Signal()
 
     # Whether to automatically show calltips on open-parentheses.
     enable_calltips = Bool(True, config=True,
         help="Whether to draw information calltips on open-parentheses.")
 
     clear_on_kernel_restart = Bool(True, config=True,
         help="Whether to clear the console when the kernel is restarted")
 
     confirm_restart = Bool(True, config=True,
         help="Whether to ask for user confirmation when restarting kernel")
     
     lexer_class = DottedObjectName(config=True,
         help="The pygments lexer class to use."
     )
     def _lexer_class_changed(self, name, old, new):
         lexer_class = import_item(new)
         self.lexer = lexer_class()
     
     def _lexer_class_default(self):
         if py3compat.PY3:
             return 'pygments.lexers.Python3Lexer'
         else:
             return 'pygments.lexers.PythonLexer'
     
     lexer = Any()
     def _lexer_default(self):
         lexer_class = import_item(self.lexer_class)
         return lexer_class()
 
     # Emitted when a user visible 'execute_request' has been submitted to the
     # kernel from the FrontendWidget. Contains the code to be executed.
     executing = QtCore.Signal(object)
 
     # Emitted when a user-visible 'execute_reply' has been received from the
     # kernel and processed by the FrontendWidget. Contains the response message.
     executed = QtCore.Signal(object)
 
     # Emitted when an exit request has been received from the kernel.
     exit_requested = QtCore.Signal(object)
 
     # Protected class variables.
     _prompt_transformer = IPythonInputSplitter(physical_line_transforms=[classic_prompt()],
                                                logical_line_transforms=[],
                                                python_line_transforms=[],
                                               )
     _CallTipRequest = namedtuple('_CallTipRequest', ['id', 'pos'])
     _CompletionRequest = namedtuple('_CompletionRequest', ['id', 'pos'])
     _ExecutionRequest = namedtuple('_ExecutionRequest', ['id', 'kind'])
     _input_splitter_class = InputSplitter
     _local_kernel = False
     _highlighter = Instance(FrontendHighlighter)
 
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
 
     def __init__(self, *args, **kw):
         super(FrontendWidget, self).__init__(*args, **kw)
         # FIXME: remove this when PySide min version is updated past 1.0.7
         # forcefully disable calltips if PySide is < 1.0.7, because they crash
         if qt.QT_API == qt.QT_API_PYSIDE:
             import PySide
             if PySide.__version_info__ < (1,0,7):
                 self.log.warn("PySide %s < 1.0.7 detected, disabling calltips" % PySide.__version__)
                 self.enable_calltips = False
 
         # FrontendWidget protected variables.
         self._bracket_matcher = BracketMatcher(self._control)
         self._call_tip_widget = CallTipWidget(self._control)
         self._completion_lexer = CompletionLexer(self.lexer)
         self._copy_raw_action = QtGui.QAction('Copy (Raw Text)', None)
         self._hidden = False
         self._highlighter = FrontendHighlighter(self, lexer=self.lexer)
         self._input_splitter = self._input_splitter_class()
         self._kernel_manager = None
         self._kernel_client = None
         self._request_info = {}
         self._request_info['execute'] = {};
         self._callback_dict = {}
 
         # Configure the ConsoleWidget.
         self.tab_width = 4
         self._set_continuation_prompt('... ')
 
         # Configure the CallTipWidget.
         self._call_tip_widget.setFont(self.font)
         self.font_changed.connect(self._call_tip_widget.setFont)
 
         # Configure actions.
         action = self._copy_raw_action
         key = QtCore.Qt.CTRL | QtCore.Qt.SHIFT | QtCore.Qt.Key_C
         action.setEnabled(False)
         action.setShortcut(QtGui.QKeySequence(key))
         action.setShortcutContext(QtCore.Qt.WidgetWithChildrenShortcut)
         action.triggered.connect(self.copy_raw)
         self.copy_available.connect(action.setEnabled)
         self.addAction(action)
 
         # Connect signal handlers.
         document = self._control.document()
         document.contentsChange.connect(self._document_contents_change)
 
         # Set flag for whether we are connected via localhost.
         self._local_kernel = kw.get('local_kernel',
                                     FrontendWidget._local_kernel)
 
         # Whether or not a clear_output call is pending new output.
         self._pending_clearoutput = False
 
     #---------------------------------------------------------------------------
     # 'ConsoleWidget' public interface
     #---------------------------------------------------------------------------
 
     def copy(self):
         """ Copy the currently selected text to the clipboard, removing prompts.
         """
         if self._page_control is not None and self._page_control.hasFocus():
             self._page_control.copy()
         elif self._control.hasFocus():
             text = self._control.textCursor().selection().toPlainText()
             if text:
                 was_newline = text[-1] == '\n'
                 text = self._prompt_transformer.transform_cell(text)
                 if not was_newline: # user doesn't need newline
                     text = text[:-1]
                 QtGui.QApplication.clipboard().setText(text)
         else:
             self.log.debug("frontend widget : unknown copy target")
 
     #---------------------------------------------------------------------------
     # 'ConsoleWidget' abstract interface
     #---------------------------------------------------------------------------
 
     def _is_complete(self, source, interactive):
         """ Returns whether 'source' can be completely processed and a new
             prompt created. When triggered by an Enter/Return key press,
             'interactive' is True; otherwise, it is False.
         """
         self._input_splitter.reset()
         try:
             complete = self._input_splitter.push(source)
         except SyntaxError:
             return True
         if interactive:
             complete = not self._input_splitter.push_accepts_more()
         return complete
 
     def _execute(self, source, hidden):
         """ Execute 'source'. If 'hidden', do not show any output.
 
         See parent class :meth:`execute` docstring for full details.
         """
         msg_id = self.kernel_client.execute(source, hidden)
         self._request_info['execute'][msg_id] = self._ExecutionRequest(msg_id, 'user')
         self._hidden = hidden
         if not hidden:
             self.executing.emit(source)
 
     def _prompt_started_hook(self):
         """ Called immediately after a new prompt is displayed.
         """
         if not self._reading:
             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.
         """
         # Flush all state from the input splitter so the next round of
         # reading input starts with a clean buffer.
         self._input_splitter.reset()
 
         if not self._reading:
             self._highlighter.highlighting_on = False
 
     def _tab_pressed(self):
         """ Called when the tab key is pressed. Returns whether to continue
             processing the event.
         """
         # Perform tab completion if:
         # 1) The cursor is in the input buffer.
         # 2) There is a non-whitespace character before the cursor.
         text = self._get_input_buffer_cursor_line()
         if text is None:
             return False
         complete = bool(text[:self._get_input_buffer_cursor_column()].strip())
         if complete:
             self._complete()
         return not complete
 
     #---------------------------------------------------------------------------
     # 'ConsoleWidget' protected interface
     #---------------------------------------------------------------------------
 
     def _context_menu_make(self, pos):
         """ Reimplemented to add an action for raw copy.
         """
         menu = super(FrontendWidget, self)._context_menu_make(pos)
         for before_action in menu.actions():
             if before_action.shortcut().matches(QtGui.QKeySequence.Paste) == \
                     QtGui.QKeySequence.ExactMatch:
                 menu.insertAction(before_action, self._copy_raw_action)
                 break
         return menu
 
     def request_interrupt_kernel(self):
         if self._executing:
             self.interrupt_kernel()
 
     def request_restart_kernel(self):
         message = 'Are you sure you want to restart the kernel?'
         self.restart_kernel(message, now=False)
 
     def _event_filter_console_keypress(self, event):
         """ Reimplemented for execution interruption and smart backspace.
         """
         key = event.key()
         if self._control_key_down(event.modifiers(), include_command=False):
 
             if key == QtCore.Qt.Key_C and self._executing:
                 self.request_interrupt_kernel()
                 return True
 
             elif key == QtCore.Qt.Key_Period:
                 self.request_restart_kernel()
                 return True
 
         elif not event.modifiers() & QtCore.Qt.AltModifier:
 
             # Smart backspace: remove four characters in one backspace if:
             # 1) everything left of the cursor is whitespace
             # 2) the four characters immediately left of the cursor are spaces
             if key == QtCore.Qt.Key_Backspace:
                 col = self._get_input_buffer_cursor_column()
                 cursor = self._control.textCursor()
                 if col > 3 and not cursor.hasSelection():
                     text = self._get_input_buffer_cursor_line()[:col]
                     if text.endswith('    ') and not text.strip():
                         cursor.movePosition(QtGui.QTextCursor.Left,
                                             QtGui.QTextCursor.KeepAnchor, 4)
                         cursor.removeSelectedText()
                         return True
 
         return super(FrontendWidget, self)._event_filter_console_keypress(event)
 
     def _insert_continuation_prompt(self, cursor):
         """ Reimplemented for auto-indentation.
         """
         super(FrontendWidget, self)._insert_continuation_prompt(cursor)
         cursor.insertText(' ' * self._input_splitter.indent_spaces)
 
     #---------------------------------------------------------------------------
     # 'BaseFrontendMixin' abstract interface
     #---------------------------------------------------------------------------
     def _handle_clear_output(self, msg):
         """Handle clear output messages."""
-        if not self._hidden and self._is_from_this_session(msg):
+        if include_output(msg):
             wait = msg['content'].get('wait', True)
             if wait:
                 self._pending_clearoutput = True
             else:
                 self.clear_output()
 
     def _handle_complete_reply(self, rep):
         """ Handle replies for tab completion.
         """
         self.log.debug("complete: %s", rep.get('content', ''))
         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():
             text = '.'.join(self._get_context())
             cursor.movePosition(QtGui.QTextCursor.Left, n=len(text))
             self._complete_with_items(cursor, rep['content']['matches'])
 
     def _silent_exec_callback(self, expr, callback):
         """Silently execute `expr` in the kernel and call `callback` with reply
 
         the `expr` is evaluated silently in the kernel (without) output in
         the frontend. Call `callback` with the
         `repr <http://docs.python.org/library/functions.html#repr> `_ as first argument
 
         Parameters
         ----------
         expr : string
             valid string to be executed by the kernel.
         callback : function
             function accepting one argument, as a string. The string will be
             the `repr` of the result of evaluating `expr`
 
         The `callback` is called with the `repr()` of the result of `expr` as
         first argument. To get the object, do `eval()` on the passed value.
 
         See Also
         --------
         _handle_exec_callback : private method, deal with calling callback with reply
 
         """
 
         # generate uuid, which would be used as an indication of whether or
         # not the unique request originated from here (can use msg id ?)
         local_uuid = str(uuid.uuid1())
         msg_id = self.kernel_client.execute('',
             silent=True, user_expressions={ local_uuid:expr })
         self._callback_dict[local_uuid] = callback
         self._request_info['execute'][msg_id] = self._ExecutionRequest(msg_id, 'silent_exec_callback')
 
     def _handle_exec_callback(self, msg):
         """Execute `callback` corresponding to `msg` reply, after ``_silent_exec_callback``
 
         Parameters
         ----------
         msg : raw message send by the kernel containing an `user_expressions`
                 and having a 'silent_exec_callback' kind.
 
         Notes
         -----
         This function will look for a `callback` associated with the
         corresponding message id. Association has been made by
         `_silent_exec_callback`. `callback` is then called with the `repr()`
         of the value of corresponding `user_expressions` as argument.
         `callback` is then removed from the known list so that any message
         coming again with the same id won't trigger it.
 
         """
 
         user_exp = msg['content'].get('user_expressions')
         if not user_exp:
             return
         for expression in user_exp:
             if expression in self._callback_dict:
                 self._callback_dict.pop(expression)(user_exp[expression])
 
     def _handle_execute_reply(self, msg):
         """ Handles replies for code execution.
         """
         self.log.debug("execute: %s", msg.get('content', ''))
         msg_id = msg['parent_header']['msg_id']
         info = self._request_info['execute'].get(msg_id)
         # unset reading flag, because if execute finished, raw_input can't
         # still be pending.
         self._reading = False
         if info and info.kind == 'user' and not self._hidden:
             # Make sure that all output from the SUB channel has been processed
             # before writing a new prompt.
             self.kernel_client.iopub_channel.flush()
 
             # Reset the ANSI style information to prevent bad text in stdout
             # from messing up our colors. We're not a true terminal so we're
             # allowed to do this.
             if self.ansi_codes:
                 self._ansi_processor.reset_sgr()
 
             content = msg['content']
             status = content['status']
             if status == 'ok':
                 self._process_execute_ok(msg)
             elif status == 'error':
                 self._process_execute_error(msg)
             elif status == 'aborted':
                 self._process_execute_abort(msg)
 
             self._show_interpreter_prompt_for_reply(msg)
             self.executed.emit(msg)
             self._request_info['execute'].pop(msg_id)
         elif info and info.kind == 'silent_exec_callback' and not self._hidden:
             self._handle_exec_callback(msg)
             self._request_info['execute'].pop(msg_id)
         else:
             super(FrontendWidget, self)._handle_execute_reply(msg)
 
     def _handle_input_request(self, msg):
         """ Handle requests for raw_input.
         """
         self.log.debug("input: %s", msg.get('content', ''))
         if self._hidden:
             raise RuntimeError('Request for raw input during hidden execution.')
 
         # Make sure that all output from the SUB channel has been processed
         # before entering readline mode.
         self.kernel_client.iopub_channel.flush()
 
         def callback(line):
             self.kernel_client.stdin_channel.input(line)
         if self._reading:
             self.log.debug("Got second input request, assuming first was interrupted.")
             self._reading = False
         self._readline(msg['content']['prompt'], callback=callback)
 
     def _kernel_restarted_message(self, died=True):
         msg = "Kernel died, restarting" if died else "Kernel restarting"
         self._append_html("<br>%s<hr><br>" % msg,
             before_prompt=False
         )
 
     def _handle_kernel_died(self, since_last_heartbeat):
         """Handle the kernel's death (if we do not own the kernel).
         """
         self.log.warn("kernel died: %s", since_last_heartbeat)
         if self.custom_restart:
             self.custom_restart_kernel_died.emit(since_last_heartbeat)
         else:
             self._kernel_restarted_message(died=True)
             self.reset()
 
     def _handle_kernel_restarted(self, died=True):
         """Notice that the autorestarter restarted the kernel.
 
         There's nothing to do but show a message.
         """
         self.log.warn("kernel restarted")
         self._kernel_restarted_message(died=died)
         self.reset()
 
     def _handle_inspect_reply(self, rep):
         """Handle replies for call tips."""
         self.log.debug("oinfo: %s", rep.get('content', ''))
         cursor = self._get_cursor()
         info = self._request_info.get('call_tip')
         if info and info.id == rep['parent_header']['msg_id'] and \
                 info.pos == cursor.position():
             content = rep['content']
             if content.get('status') == 'ok':
                 self._call_tip_widget.show_inspect_data(content)
 
     def _handle_execute_result(self, msg):
         """ Handle display hook output.
         """
         self.log.debug("execute_result: %s", msg.get('content', ''))
-        if not self._hidden and self._is_from_this_session(msg):
+        if self.include_output(msg):
             self.flush_clearoutput()
             text = msg['content']['data']
             self._append_plain_text(text + '\n', before_prompt=True)
 
     def _handle_stream(self, msg):
         """ Handle stdout, stderr, and stdin.
         """
         self.log.debug("stream: %s", msg.get('content', ''))
-        if not self._hidden and self._is_from_this_session(msg):
+        if self.include_output(msg):
             self.flush_clearoutput()
             self.append_stream(msg['content']['text'])
 
     def _handle_shutdown_reply(self, msg):
         """ Handle shutdown signal, only if from other console.
         """
         self.log.info("shutdown: %s", msg.get('content', ''))
         restart = msg.get('content', {}).get('restart', False)
-        if not self._hidden and not self._is_from_this_session(msg):
+        if not self._hidden and not self.from_here(msg):
             # got shutdown reply, request came from session other than ours
             if restart:
                 # someone restarted the kernel, handle it
                 self._handle_kernel_restarted(died=False)
             else:
                 # kernel was shutdown permanently
                 # this triggers exit_requested if the kernel was local,
                 # and a dialog if the kernel was remote,
                 # so we don't suddenly clear the qtconsole without asking.
                 if self._local_kernel:
                     self.exit_requested.emit(self)
                 else:
                     title = self.window().windowTitle()
                     reply = QtGui.QMessageBox.question(self, title,
                         "Kernel has been shutdown permanently. "
                         "Close the Console?",
                         QtGui.QMessageBox.Yes,QtGui.QMessageBox.No)
                     if reply == QtGui.QMessageBox.Yes:
                         self.exit_requested.emit(self)
 
     def _handle_status(self, msg):
         """Handle status message"""
         # This is where a busy/idle indicator would be triggered,
         # when we make one.
         state = msg['content'].get('execution_state', '')
         if state == 'starting':
             # kernel started while we were running
             if self._executing:
                 self._handle_kernel_restarted(died=True)
         elif state == 'idle':
             pass
         elif state == 'busy':
             pass
 
     def _started_channels(self):
         """ Called when the KernelManager channels have started listening or
             when the frontend is assigned an already listening KernelManager.
         """
         self.reset(clear=True)
 
     #---------------------------------------------------------------------------
     # 'FrontendWidget' public interface
     #---------------------------------------------------------------------------
 
     def copy_raw(self):
         """ Copy the currently selected text to the clipboard without attempting
             to remove prompts or otherwise alter the text.
         """
         self._control.copy()
 
     def execute_file(self, path, hidden=False):
         """ Attempts to execute file with 'path'. If 'hidden', no output is
             shown.
         """
         self.execute('execfile(%r)' % path, hidden=hidden)
 
     def interrupt_kernel(self):
         """ Attempts to interrupt the running kernel.
         
         Also unsets _reading flag, to avoid runtime errors
         if raw_input is called again.
         """
         if self.custom_interrupt:
             self._reading = False
             self.custom_interrupt_requested.emit()
         elif self.kernel_manager:
             self._reading = False
             self.kernel_manager.interrupt_kernel()
         else:
             self._append_plain_text('Cannot interrupt a kernel I did not start.\n')
 
     def reset(self, clear=False):
         """ Resets the widget to its initial state if ``clear`` parameter
         is True, otherwise
         prints a visual indication of the fact that the kernel restarted, but
         does not clear the traces from previous usage of the kernel before it
         was restarted.  With ``clear=True``, it is similar to ``%clear``, but
         also re-writes the banner and aborts execution if necessary.
         """
         if self._executing:
             self._executing = False
             self._request_info['execute'] = {}
         self._reading = False
         self._highlighter.highlighting_on = False
 
         if clear:
             self._control.clear()
             self._append_plain_text(self.banner)
             if self.kernel_banner:
                 self._append_plain_text(self.kernel_banner)
                 
         # update output marker for stdout/stderr, so that startup
         # messages appear after banner:
         self._append_before_prompt_pos = self._get_cursor().position()
         self._show_interpreter_prompt()
 
     def restart_kernel(self, message, now=False):
         """ Attempts to restart the running kernel.
         """
         # FIXME: now should be configurable via a checkbox in the dialog.  Right
         # now at least the heartbeat path sets it to True and the manual restart
         # to False.  But those should just be the pre-selected states of a
         # checkbox that the user could override if so desired.  But I don't know
         # enough Qt to go implementing the checkbox now.
 
         if self.custom_restart:
             self.custom_restart_requested.emit()
             return
 
         if self.kernel_manager:
             # Pause the heart beat channel to prevent further warnings.
             self.kernel_client.hb_channel.pause()
 
             # Prompt the user to restart the kernel. Un-pause the heartbeat if
             # they decline. (If they accept, the heartbeat will be un-paused
             # automatically when the kernel is restarted.)
             if self.confirm_restart:
                 buttons = QtGui.QMessageBox.Yes | QtGui.QMessageBox.No
                 result = QtGui.QMessageBox.question(self, 'Restart kernel?',
                                                     message, buttons)
                 do_restart = result == QtGui.QMessageBox.Yes
             else:
                 # confirm_restart is False, so we don't need to ask user
                 # anything, just do the restart
                 do_restart = True
             if do_restart:
                 try:
                     self.kernel_manager.restart_kernel(now=now)
                 except RuntimeError as e:
                     self._append_plain_text(
                         'Error restarting kernel: %s\n' % e,
                         before_prompt=True
                     )
                 else:
                     self._append_html("<br>Restarting kernel...\n<hr><br>",
                         before_prompt=True,
                     )
             else:
                 self.kernel_client.hb_channel.unpause()
 
         else:
             self._append_plain_text(
                 'Cannot restart a Kernel I did not start\n',
                 before_prompt=True
             )
 
     def append_stream(self, text):
         """Appends text to the output stream."""
         # Most consoles treat tabs as being 8 space characters. Convert tabs
         # to spaces so that output looks as expected regardless of this
         # widget's tab width.
         text = text.expandtabs(8)
         self._append_plain_text(text, before_prompt=True)
         self._control.moveCursor(QtGui.QTextCursor.End)
 
     def flush_clearoutput(self):
         """If a clearoutput is pending, execute it."""
         if self._pending_clearoutput:
             self._pending_clearoutput = False
             self.clear_output()
 
     def clear_output(self):
         """Clears the current line of output."""
         cursor = self._control.textCursor()
         cursor.beginEditBlock()
         cursor.movePosition(cursor.StartOfLine, cursor.KeepAnchor)
         cursor.insertText('')
         cursor.endEditBlock()
 
     #---------------------------------------------------------------------------
     # '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
         if not self.enable_calltips or not self.kernel_client.shell_channel.is_alive():
             return False
         cursor_pos = self._get_input_buffer_cursor_pos()
         code = self.input_buffer
         # Send the metadata request to the kernel
         msg_id = self.kernel_client.inspect(code, cursor_pos)
         pos = self._get_cursor().position()
         self._request_info['call_tip'] = self._CallTipRequest(msg_id, pos)
         return True
 
     def _complete(self):
         """ Performs completion at the current cursor location.
         """
         context = self._get_context()
         if context:
             # Send the completion request to the kernel
             msg_id = self.kernel_client.complete(
                 code=self.input_buffer,
                 cursor_pos=self._get_input_buffer_cursor_pos(),
             )
             pos = self._get_cursor().position()
             info = self._CompletionRequest(msg_id, pos)
             self._request_info['complete'] = info
 
     def _get_context(self, cursor=None):
         """ Gets the context for the specified cursor (or the current cursor
             if none is specified).
         """
         if cursor is None:
             cursor = self._get_cursor()
         cursor.movePosition(QtGui.QTextCursor.StartOfBlock,
                             QtGui.QTextCursor.KeepAnchor)
         text = cursor.selection().toPlainText()
         return self._completion_lexer.get_context(text)
 
     def _process_execute_abort(self, msg):
         """ Process a reply for an aborted execution request.
         """
         self._append_plain_text("ERROR: execution aborted\n")
 
     def _process_execute_error(self, msg):
         """ Process a reply for an execution request that resulted in an error.
         """
         content = msg['content']
         # If a SystemExit is passed along, this means exit() was called - also
         # all the ipython %exit magic syntax of '-k' to be used to keep
         # the kernel running
         if content['ename']=='SystemExit':
             keepkernel = content['evalue']=='-k' or content['evalue']=='True'
             self._keep_kernel_on_exit = keepkernel
             self.exit_requested.emit(self)
         else:
             traceback = ''.join(content['traceback'])
             self._append_plain_text(traceback)
 
     def _process_execute_ok(self, msg):
         """ Process a reply for a successful execution request.
         """
         payload = msg['content']['payload']
         for item in payload:
             if not self._process_execute_payload(item):
                 warning = 'Warning: received unknown payload of type %s'
                 print(warning % repr(item['source']))
 
     def _process_execute_payload(self, item):
         """ Process a single payload item from the list of payload items in an
             execution reply. Returns whether the payload was handled.
         """
         # The basic FrontendWidget doesn't handle payloads, as they are a
         # mechanism for going beyond the standard Python interpreter model.
         return False
 
     def _show_interpreter_prompt(self):
         """ Shows a prompt for the interpreter.
         """
         self._show_prompt('>>> ')
 
     def _show_interpreter_prompt_for_reply(self, msg):
         """ Shows a prompt for the interpreter given an 'execute_reply' message.
         """
         self._show_interpreter_prompt()
 
     #------ Signal handlers ----------------------------------------------------
 
     def _document_contents_change(self, position, removed, added):
         """ Called whenever the document's content changes. Display a call tip
             if appropriate.
         """
         # Calculate where the cursor should be *after* the change:
         position += added
 
         document = self._control.document()
         if position == self._get_cursor().position():
             self._call_tip()
 
     #------ Trait default initializers -----------------------------------------
 
     def _banner_default(self):
         """ Returns the standard Python banner.
         """
         banner = 'Python %s on %s\nType "help", "copyright", "credits" or ' \
             '"license" for more information.'
         return banner % (sys.version, sys.platform)

IPython/qt/console/ipython_widget.py

@@ -1,581 +1,591 b''
 """A FrontendWidget that emulates the interface of the console IPython.
 
 This supports the additional functionality provided by the IPython kernel.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 from collections import namedtuple
 import os.path
 import re
 from subprocess import Popen
 import sys
 import time
 from textwrap import dedent
 
 from IPython.external.qt import QtCore, QtGui
 
 from IPython.core.inputsplitter import IPythonInputSplitter
 from IPython.core.release import version
 from IPython.core.inputtransformer import ipy_prompt
 from IPython.utils.traitlets import Bool, Unicode
 from .frontend_widget import FrontendWidget
 from . import styles
 
 #-----------------------------------------------------------------------------
 # 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.kernel.zmq.zmqshell.ZMQInteractiveShell'
 
 if sys.platform.startswith('win'):
     default_editor = 'notepad'
 else:
     default_editor = ''
 
 #-----------------------------------------------------------------------------
 # 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)
 
     editor = Unicode(default_editor, config=True,
         help="""
         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_line = Unicode(config=True,
         help="""
         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.
         """)
 
     style_sheet = Unicode(config=True,
         help="""
         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 = Unicode(config=True,
         help="""
         If not empty, use this Pygments style for syntax highlighting.
         Otherwise, the style sheet is queried for Pygments style
         information.
         """)
 
     # Prompts.
     in_prompt = Unicode(default_in_prompt, config=True)
     out_prompt = Unicode(default_out_prompt, config=True)
     input_sep = Unicode(default_input_sep, config=True)
     output_sep = Unicode(default_output_sep, config=True)
     output_sep2 = Unicode(default_output_sep2, config=True)
 
     # FrontendWidget protected class variables.
     _input_splitter_class = IPythonInputSplitter
     _prompt_transformer = IPythonInputSplitter(physical_line_transforms=[ipy_prompt()],
                                                logical_line_transforms=[],
                                                python_line_transforms=[],
                                               )
 
     # IPythonWidget protected class variables.
     _PromptBlock = namedtuple('_PromptBlock', ['block', 'length', 'number'])
     _payload_source_edit = 'edit_magic'
     _payload_source_exit = 'ask_exit'
     _payload_source_next_input = 'set_next_input'
     _payload_source_page = 'page'
     _retrying_history_request = False
     _starting = False
 
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
 
     def __init__(self, *args, **kw):
         super(IPythonWidget, self).__init__(*args, **kw)
 
         # IPythonWidget protected variables.
         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_next_input : self._handle_payload_next_input }
         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()
 
         self._guiref_loaded = False
 
     #---------------------------------------------------------------------------
     # 'BaseFrontendMixin' abstract interface
     #---------------------------------------------------------------------------
     def _handle_complete_reply(self, rep):
         """ Reimplemented to support IPython's improved completion machinery.
         """
         self.log.debug("complete: %s", rep.get('content', ''))
         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():
             content = rep['content']
             matches = content['matches']
             start = content['cursor_start']
             end = content['cursor_end']
             
             start = max(start, 0)
             end = max(end, start + 1)
 
             # Move the control's cursor to the desired end point
             cursor_pos = self._get_input_buffer_cursor_pos()
             if end < cursor_pos:
                 cursor.movePosition(QtGui.QTextCursor.Left,
                                     n=(cursor_pos - end))
             elif end > cursor_pos:
                 cursor.movePosition(QtGui.QTextCursor.Right,
                                     n=(end - cursor_pos))
             # This line actually applies the move to control's cursor
             self._control.setTextCursor(cursor)
 
             offset = end - start
             # Move the local cursor object 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.
         """
         msg_id = msg['parent_header'].get('msg_id')
         info = self._request_info['execute'].get(msg_id)
         if info and info.kind == 'prompt':
             content = msg['content']
             if content['status'] == 'aborted':
                 self._show_interpreter_prompt()
             else:
                 number = content['execution_count'] + 1
                 self._show_interpreter_prompt(number)
             self._request_info['execute'].pop(msg_id)
         else:
             super(IPythonWidget, self)._handle_execute_reply(msg)
 
     def _handle_history_reply(self, msg):
         """ Implemented to handle history tail replies, which are only supported
             by the IPython kernel.
         """
         content = msg['content']
         if 'history' not in content:
             self.log.error("History request failed: %r"%content)
             if content.get('status', '') == 'aborted' and \
                                             not self._retrying_history_request:
                 # a *different* action caused this request to be aborted, so
                 # we should try again.
                 self.log.error("Retrying aborted history request")
                 # prevent multiple retries of aborted requests:
                 self._retrying_history_request = True
                 # wait out the kernel's queue flush, which is currently timed at 0.1s
                 time.sleep(0.25)
                 self.kernel_client.shell_channel.history(hist_access_type='tail',n=1000)
             else:
                 self._retrying_history_request = False
             return
         # reset retry flag
         self._retrying_history_request = False
         history_items = content['history']
         self.log.debug("Received history reply with %i entries", len(history_items))
         items = []
         last_cell = u""
         for _, _, cell in history_items:
             cell = cell.rstrip()
             if cell != last_cell:
                 items.append(cell)
                 last_cell = cell
         self._set_history(items)
 
+    def _handle_execute_input(self, msg):
+        """Handle an execute_input message"""
+        self.log.debug("execute_input: %s", msg.get('content', ''))
+        if self.include_output(msg):
+            content = msg['content']
+            prompt_number = content.get('execution_count', 0)
+            self._append_html(self._make_in_prompt(prompt_number), True)
+            self._append_plain_text(content['code'], True)
+        
+    
     def _handle_execute_result(self, msg):
         """ Reimplemented for IPython-style "display hook".
         """
         self.log.debug("execute_result: %s", msg.get('content', ''))
-        if not self._hidden and self._is_from_this_session(msg):
+        if self.include_output(msg):
             self.flush_clearoutput()
             content = msg['content']
             prompt_number = content.get('execution_count', 0)
             data = content['data']
             if 'text/plain' in data:
                 self._append_plain_text(self.output_sep, True)
                 self._append_html(self._make_out_prompt(prompt_number), True)
                 text = data['text/plain']
                 # If the repr is multiline, make sure we start on a new line,
                 # so that its lines are aligned.
                 if "\n" in text and not self.output_sep.endswith("\n"):
                     self._append_plain_text('\n', True)
                 self._append_plain_text(text + self.output_sep2, True)
 
     def _handle_display_data(self, msg):
         """ The base handler for the ``display_data`` message.
         """
         self.log.debug("display: %s", msg.get('content', ''))
         # 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):
+        if self.include_output(msg):
             self.flush_clearoutput()
             data = msg['content']['data']
             metadata = msg['content']['metadata']
             # In the regular IPythonWidget, we simply print the plain text
             # representation.
             if 'text/plain' in data:
                 text = data['text/plain']
                 self._append_plain_text(text, True)
             # This newline seems to be needed for text and html output.
             self._append_plain_text(u'\n', True)
 
     def _handle_kernel_info_reply(self, rep):
         """Handle kernel info replies."""
         content = rep['content']
         if not self._guiref_loaded:
             if content.get('language') == 'python':
                 self._load_guiref_magic()
             self._guiref_loaded = True
         
         self.kernel_banner = content.get('banner', '')
         if self._starting:
             # finish handling started channels
             self._starting = False
             super(IPythonWidget, self)._started_channels()
 
     def _started_channels(self):
         """Reimplemented to make a history request and load %guiref."""
         self._starting = True
         # The reply will trigger %guiref load provided language=='python'
         self.kernel_client.kernel_info()
 
         self.kernel_client.shell_channel.history(hist_access_type='tail',
                                                   n=1000)
     
     def _load_guiref_magic(self):
         """Load %guiref magic."""
         self.kernel_client.shell_channel.execute('\n'.join([
             "try:",
             "    _usage",
             "except:",
             "    from IPython.core import usage as _usage",
             "    get_ipython().register_magic_function(_usage.page_guiref, 'line', 'guiref')",
             "    del _usage",
         ]), silent=True)
         
     #---------------------------------------------------------------------------
     # 'ConsoleWidget' public interface
     #---------------------------------------------------------------------------
 
     #---------------------------------------------------------------------------
     # 'FrontendWidget' public interface
     #---------------------------------------------------------------------------
 
     def execute_file(self, path, hidden=False):
         """ Reimplemented to use the 'run' magic.
         """
         # Use forward slashes on Windows to avoid escaping each separator.
         if sys.platform == 'win32':
             path = os.path.normpath(path).replace('\\', '/')
 
         # Perhaps we should not be using %run directly, but while we
         # are, it is necessary to quote or escape filenames containing spaces 
         # or quotes. 
         
         # In earlier code here, to minimize escaping, we sometimes quoted the 
         # filename with single quotes. But to do this, this code must be
         # platform-aware, because run uses shlex rather than python string
         # parsing, so that:
         # * In Win: single quotes can be used in the filename without quoting,
         #   and we cannot use single quotes to quote the filename.
         # * In *nix: we can escape double quotes in a double quoted filename,
         #   but can't escape single quotes in a single quoted filename.
         
         # So to keep this code non-platform-specific and simple, we now only
         # use double quotes to quote filenames, and escape when needed:
         if ' ' in path or "'" in path or '"' in path:
             path = '"%s"' % path.replace('"', '\\"')
         self.execute('%%run %s' % path, hidden=hidden)
 
     #---------------------------------------------------------------------------
     # 'FrontendWidget' protected interface
     #---------------------------------------------------------------------------
 
     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_client.shell_channel.execute('', silent=True)
             info = self._ExecutionRequest(msg_id, 'prompt')
             self._request_info['execute'][msg_id] = 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)
 
     def _show_interpreter_prompt_for_reply(self, msg):
         """ Reimplemented for IPython-style prompts.
         """
         # Update the old prompt number if necessary.
         content = msg['content']
         # abort replies do not have any keys:
         if content['status'] == 'aborted':
             if self._previous_prompt_obj:
                 previous_prompt_number = self._previous_prompt_obj.number
             else:
                 previous_prompt_number = 0
         else:
             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 = styles.default_light_style_sheet
             self.syntax_style = styles.default_light_syntax_style
         elif colors=='linux':
             self.style_sheet = styles.default_dark_style_sheet
             self.syntax_style = styles.default_dark_syntax_style
         elif colors=='nocolor':
             self.style_sheet = styles.default_bw_style_sheet
             self.syntax_style = styles.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 not self.editor:
             self._append_plain_text('No default editor available.\n'
             'Specify a GUI text editor in the `IPythonWidget.editor` '
             'configurable to enable the %edit magic')
         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.
         """
         try:
             body = self.in_prompt % number
         except TypeError:
             # allow in_prompt to leave out number, e.g. '>>> '
             from xml.sax.saxutils import escape
             body = escape(self.in_prompt)
         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.
         """
         try:
             body = self.out_prompt % number
         except TypeError:
             # allow out_prompt to leave out number, e.g. '<<< '
             from xml.sax.saxutils import escape
             body = escape(self.out_prompt)
         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(self)
 
     def _handle_payload_next_input(self, item):
         self.input_buffer = 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.
         data = item['data']
         if 'text/html' in data and self.kind == 'rich':
             self._page(data['text/html'], html=True)
         else:
             self._page(data['text/plain'], html=False)
 
     #------ Trait change handlers --------------------------------------------
 
     def _style_sheet_changed(self):
         """ Set the style sheets of the underlying widgets.
         """
         self.setStyleSheet(self.style_sheet)
         if self._control is not None:
             self._control.document().setDefaultStyleSheet(self.style_sheet)
             bg_color = self._control.palette().window().color()
             self._ansi_processor.set_background_color(bg_color)
         
         if self._page_control is not None:
             self._page_control.document().setDefaultStyleSheet(self.style_sheet)
 
 
 
     def _syntax_style_changed(self):
         """ Set the style for the syntax highlighter.
         """
         if self._highlighter is None:
             # ignore premature calls
             return
         if self.syntax_style:
             self._highlighter.set_style(self.syntax_style)
         else:
             self._highlighter.set_style_sheet(self.style_sheet)
 
     #------ Trait default initializers -----------------------------------------
 
     def _banner_default(self):
         return "IPython QtConsole {version}\n".format(version=version)

IPython/qt/console/rich_ipython_widget.py

@@ -1,347 +1,347 b''
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 from base64 import decodestring
 import os
 import re
 
 from IPython.external.qt import QtCore, QtGui
 
 from IPython.lib.latextools import latex_to_png
 from IPython.utils.path import ensure_dir_exists
 from IPython.utils.traitlets import Bool
 from IPython.qt.svg import save_svg, svg_to_clipboard, svg_to_image
 from .ipython_widget import IPythonWidget
 
 
 class RichIPythonWidget(IPythonWidget):
     """ An IPythonWidget that supports rich text, including lists, images, and
         tables. Note that raw performance will be reduced compared to the plain
         text version.
     """
 
     # RichIPythonWidget protected class variables.
     _payload_source_plot = 'IPython.kernel.zmq.pylab.backend_payload.add_plot_payload'
     _jpg_supported = Bool(False)
 
     # Used to determine whether a given html export attempt has already
     # displayed a warning about being unable to convert a png to svg.
     _svg_warning_displayed = False
 
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
 
     def __init__(self, *args, **kw):
         """ Create a RichIPythonWidget.
         """
         kw['kind'] = 'rich'
         super(RichIPythonWidget, self).__init__(*args, **kw)
 
         # Configure the ConsoleWidget HTML exporter for our formats.
         self._html_exporter.image_tag = self._get_image_tag
 
         # Dictionary for resolving document resource names to SVG data.
         self._name_to_svg_map = {}
 
         # Do we support jpg ?
         # it seems that sometime jpg support is a plugin of QT, so try to assume
         # it is not always supported.
         _supported_format = map(str, QtGui.QImageReader.supportedImageFormats())
         self._jpg_supported = 'jpeg' in _supported_format
 
 
     #---------------------------------------------------------------------------
     # 'ConsoleWidget' public interface overides
     #---------------------------------------------------------------------------
 
     def export_html(self):
         """ Shows a dialog to export HTML/XML in various formats.
 
         Overridden in order to reset the _svg_warning_displayed flag prior
         to the export running.
         """
         self._svg_warning_displayed = False
         super(RichIPythonWidget, self).export_html()
 
 
     #---------------------------------------------------------------------------
     # 'ConsoleWidget' protected interface
     #---------------------------------------------------------------------------
 
     def _context_menu_make(self, pos):
         """ Reimplemented to return a custom context menu for images.
         """
         format = self._control.cursorForPosition(pos).charFormat()
         name = format.stringProperty(QtGui.QTextFormat.ImageName)
         if name:
             menu = QtGui.QMenu()
 
             menu.addAction('Copy Image', lambda: self._copy_image(name))
             menu.addAction('Save Image As...', lambda: self._save_image(name))
             menu.addSeparator()
 
             svg = self._name_to_svg_map.get(name, None)
             if svg is not None:
                 menu.addSeparator()
                 menu.addAction('Copy SVG', lambda: svg_to_clipboard(svg))
                 menu.addAction('Save SVG As...',
                                lambda: save_svg(svg, self._control))
         else:
             menu = super(RichIPythonWidget, self)._context_menu_make(pos)
         return menu
 
     #---------------------------------------------------------------------------
     # 'BaseFrontendMixin' abstract interface
     #---------------------------------------------------------------------------
     def _pre_image_append(self, msg, prompt_number):
         """ Append the Out[] prompt  and make the output nicer
 
         Shared code for some the following if statement
         """
         self.log.debug("execute_result: %s", msg.get('content', ''))
         self._append_plain_text(self.output_sep, True)
         self._append_html(self._make_out_prompt(prompt_number), True)
         self._append_plain_text('\n', True)
 
     def _handle_execute_result(self, msg):
         """ Overridden to handle rich data types, like SVG.
         """
-        if not self._hidden and self._is_from_this_session(msg):
+        if self.include_output(msg):
             self.flush_clearoutput()
             content = msg['content']
             prompt_number = content.get('execution_count', 0)
             data = content['data']
             metadata = msg['content']['metadata']
             if 'image/svg+xml' in data:
                 self._pre_image_append(msg, prompt_number)
                 self._append_svg(data['image/svg+xml'], True)
                 self._append_html(self.output_sep2, True)
             elif 'image/png' in data:
                 self._pre_image_append(msg, prompt_number)
                 png = decodestring(data['image/png'].encode('ascii'))
                 self._append_png(png, True, metadata=metadata.get('image/png', None))
                 self._append_html(self.output_sep2, True)
             elif 'image/jpeg' in data and self._jpg_supported:
                 self._pre_image_append(msg, prompt_number)
                 jpg = decodestring(data['image/jpeg'].encode('ascii'))
                 self._append_jpg(jpg, True, metadata=metadata.get('image/jpeg', None))
                 self._append_html(self.output_sep2, True)
             elif 'text/latex' in data:
                 self._pre_image_append(msg, prompt_number)
                 latex = data['text/latex'].encode('ascii')
                 # latex_to_png takes care of handling $
                 latex = latex.strip('$')
                 png = latex_to_png(latex, wrap=True)
                 if png is not None:
                     self._append_png(png, True)
                     self._append_html(self.output_sep2, True)
                 else:
                     # Print plain text if png can't be generated
                     return super(RichIPythonWidget, self)._handle_execute_result(msg)
             else:
                 # Default back to the plain text representation.
                 return super(RichIPythonWidget, self)._handle_execute_result(msg)
 
     def _handle_display_data(self, msg):
         """ Overridden to handle rich data types, like SVG.
         """
-        if not self._hidden and self._is_from_this_session(msg):
+        if self.include_output(msg):
             self.flush_clearoutput()
             data = msg['content']['data']
             metadata = msg['content']['metadata']
             # Try to use the svg or html representations.
             # FIXME: Is this the right ordering of things to try?
             if 'image/svg+xml' in data:
                 self.log.debug("display: %s", msg.get('content', ''))
                 svg = data['image/svg+xml']
                 self._append_svg(svg, True)
             elif 'image/png' in data:
                 self.log.debug("display: %s", msg.get('content', ''))
                 # PNG data is base64 encoded as it passes over the network
                 # in a JSON structure so we decode it.
                 png = decodestring(data['image/png'].encode('ascii'))
                 self._append_png(png, True, metadata=metadata.get('image/png', None))
             elif 'image/jpeg' in data and self._jpg_supported:
                 self.log.debug("display: %s", msg.get('content', ''))
                 jpg = decodestring(data['image/jpeg'].encode('ascii'))
                 self._append_jpg(jpg, True, metadata=metadata.get('image/jpeg', None))
             else:
                 # Default back to the plain text representation.
                 return super(RichIPythonWidget, self)._handle_display_data(msg)
 
     #---------------------------------------------------------------------------
     # 'RichIPythonWidget' protected interface
     #---------------------------------------------------------------------------
 
     def _append_jpg(self, jpg, before_prompt=False, metadata=None):
         """ Append raw JPG data to the widget."""
         self._append_custom(self._insert_jpg, jpg, before_prompt, metadata=metadata)
 
     def _append_png(self, png, before_prompt=False, metadata=None):
         """ Append raw PNG data to the widget.
         """
         self._append_custom(self._insert_png, png, before_prompt, metadata=metadata)
 
     def _append_svg(self, svg, before_prompt=False):
         """ Append raw SVG data to the widget.
         """
         self._append_custom(self._insert_svg, svg, before_prompt)
 
     def _add_image(self, image):
         """ Adds the specified QImage to the document and returns a
             QTextImageFormat that references it.
         """
         document = self._control.document()
         name = str(image.cacheKey())
         document.addResource(QtGui.QTextDocument.ImageResource,
                              QtCore.QUrl(name), image)
         format = QtGui.QTextImageFormat()
         format.setName(name)
         return format
 
     def _copy_image(self, name):
         """ Copies the ImageResource with 'name' to the clipboard.
         """
         image = self._get_image(name)
         QtGui.QApplication.clipboard().setImage(image)
 
     def _get_image(self, name):
         """ Returns the QImage stored as the ImageResource with 'name'.
         """
         document = self._control.document()
         image = document.resource(QtGui.QTextDocument.ImageResource,
                                   QtCore.QUrl(name))
         return image
 
     def _get_image_tag(self, match, path = None, format = "png"):
         """ Return (X)HTML mark-up for the image-tag given by match.
 
         Parameters
         ----------
         match : re.SRE_Match
             A match to an HTML image tag as exported by Qt, with
             match.group("Name") containing the matched image ID.
 
         path : string|None, optional [default None]
             If not None, specifies a path to which supporting files may be
             written (e.g., for linked images).  If None, all images are to be
             included inline.
 
         format : "png"|"svg"|"jpg", optional [default "png"]
             Format for returned or referenced images.
         """
         if format in ("png","jpg"):
             try:
                 image = self._get_image(match.group("name"))
             except KeyError:
                 return "<b>Couldn't find image %s</b>" % match.group("name")
 
             if path is not None:
                 ensure_dir_exists(path)
                 relpath = os.path.basename(path)
                 if image.save("%s/qt_img%s.%s" % (path, match.group("name"), format),
                               "PNG"):
                     return '<img src="%s/qt_img%s.%s">' % (relpath,
                                                             match.group("name"),format)
                 else:
                     return "<b>Couldn't save image!</b>"
             else:
                 ba = QtCore.QByteArray()
                 buffer_ = QtCore.QBuffer(ba)
                 buffer_.open(QtCore.QIODevice.WriteOnly)
                 image.save(buffer_, format.upper())
                 buffer_.close()
                 return '<img src="data:image/%s;base64,\n%s\n" />' % (
                     format,re.sub(r'(.{60})',r'\1\n',str(ba.toBase64())))
 
         elif format == "svg":
             try:
                 svg = str(self._name_to_svg_map[match.group("name")])
             except KeyError:
                 if not self._svg_warning_displayed:
                     QtGui.QMessageBox.warning(self, 'Error converting PNG to SVG.',
                         'Cannot convert PNG images to SVG, export with PNG figures instead. '
                         'If you want to export matplotlib figures as SVG, add '
                         'to your ipython config:\n\n'
                         '\tc.InlineBackend.figure_format = \'svg\'\n\n'
                         'And regenerate the figures.',
                                               QtGui.QMessageBox.Ok)
                     self._svg_warning_displayed = True
                 return ("<b>Cannot convert  PNG images to SVG.</b>  "
                         "You must export this session with PNG images. "
                         "If you want to export matplotlib figures as SVG, add to your config "
                         "<span>c.InlineBackend.figure_format = 'svg'</span> "
                         "and regenerate the figures.")
 
             # Not currently checking path, because it's tricky to find a
             # cross-browser way to embed external SVG images (e.g., via
             # object or embed tags).
 
             # Chop stand-alone header from matplotlib SVG
             offset = svg.find("<svg")
             assert(offset > -1)
 
             return svg[offset:]
 
         else:
             return '<b>Unrecognized image format</b>'
 
     def _insert_jpg(self, cursor, jpg, metadata=None):
         """ Insert raw PNG data into the widget."""
         self._insert_img(cursor, jpg, 'jpg', metadata=metadata)
 
     def _insert_png(self, cursor, png, metadata=None):
         """ Insert raw PNG data into the widget.
         """
         self._insert_img(cursor, png, 'png', metadata=metadata)
 
     def _insert_img(self, cursor, img, fmt, metadata=None):
         """ insert a raw image, jpg or png """
         if metadata:
             width = metadata.get('width', None)
             height = metadata.get('height', None)
         else:
             width = height = None
         try:
             image = QtGui.QImage()
             image.loadFromData(img, fmt.upper())
             if width and height:
                 image = image.scaled(width, height, transformMode=QtCore.Qt.SmoothTransformation)
             elif width and not height:
                 image = image.scaledToWidth(width, transformMode=QtCore.Qt.SmoothTransformation)
             elif height and not width:
                 image = image.scaledToHeight(height, transformMode=QtCore.Qt.SmoothTransformation)
         except ValueError:
             self._insert_plain_text(cursor, 'Received invalid %s data.'%fmt)
         else:
             format = self._add_image(image)
             cursor.insertBlock()
             cursor.insertImage(format)
             cursor.insertBlock()
 
     def _insert_svg(self, cursor, svg):
         """ Insert raw SVG data into the widet.
         """
         try:
             image = svg_to_image(svg)
         except ValueError:
             self._insert_plain_text(cursor, 'Received invalid SVG data.')
         else:
             format = self._add_image(image)
             self._name_to_svg_map[format.name()] = svg
             cursor.insertBlock()
             cursor.insertImage(format)
             cursor.insertBlock()
 
     def _save_image(self, name, format='PNG'):
         """ Shows a save dialog for the ImageResource with 'name'.
         """
         dialog = QtGui.QFileDialog(self._control, 'Save Image')
         dialog.setAcceptMode(QtGui.QFileDialog.AcceptSave)
         dialog.setDefaultSuffix(format.lower())
         dialog.setNameFilter('%s file (*.%s)' % (format, format.lower()))
         if dialog.exec_():
             filename = dialog.selectedFiles()[0]
             image = self._get_image(name)
             image.save(filename, format)