ENH: Better handling of continuation lines

IPython/frontend/wx/console_widget.py

@@ -1,482 +1,507 b''
 # encoding: utf-8
 """
 A Wx widget to act as a console and input commands.
 
 This widget deals with prompts and provides an edit buffer
 restricted to after the last prompt.
 """
 
 __docformat__ = "restructuredtext en"
 
 #-------------------------------------------------------------------------------
 #  Copyright (C) 2008  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is
 #  in the file COPYING, distributed as part of this software.
 #-------------------------------------------------------------------------------
 
 #-------------------------------------------------------------------------------
 # Imports
 #-------------------------------------------------------------------------------
 
 import wx
 import wx.stc  as  stc
 
 from wx.py import editwindow
 import time
 import sys
 LINESEP = '\n'
 if sys.platform == 'win32':
     LINESEP = '\n\r'
 
 import re
 
 # FIXME: Need to provide an API for non user-generated display on the
 # screen: this should not be editable by the user.
 
 _DEFAULT_SIZE = 10
 if sys.platform == 'darwin':
     _DEFAULT_SIZE = 12
 
 _DEFAULT_STYLE = {
     'stdout'      : 'fore:#0000FF',
     'stderr'      : 'fore:#007f00',
     'trace'       : 'fore:#FF0000',
 
     'default'     : 'size:%d' % _DEFAULT_SIZE,
     'bracegood'   : 'fore:#00AA00,back:#000000,bold',
     'bracebad'    : 'fore:#FF0000,back:#000000,bold',
 
     # properties for the various Python lexer styles
     'comment'       : 'fore:#007F00',
     'number'        : 'fore:#007F7F',
     'string'        : 'fore:#7F007F,italic',
     'char'          : 'fore:#7F007F,italic',
     'keyword'       : 'fore:#00007F,bold',
     'triple'        : 'fore:#7F0000',
     'tripledouble'  : 'fore:#7F0000',
     'class'         : 'fore:#0000FF,bold,underline',
     'def'           : 'fore:#007F7F,bold',
     'operator'      : 'bold'
     }
 
 # new style numbers
 _STDOUT_STYLE = 15
 _STDERR_STYLE = 16
 _TRACE_STYLE  = 17
 
 
 # system colors
 #SYS_COLOUR_BACKGROUND = wx.SystemSettings.GetColour(wx.SYS_COLOUR_BACKGROUND)
 
 #-------------------------------------------------------------------------------
 # The console widget class
 #-------------------------------------------------------------------------------
 class ConsoleWidget(editwindow.EditWindow):
     """ Specialized styled text control view for console-like workflow.
 
         This widget is mainly interested in dealing with the prompt and
         keeping the cursor inside the editing line.
     """
 
     # This is where the title captured from the ANSI escape sequences are
     # stored.
     title = 'Console'
 
     # The buffer being edited.
     def _set_input_buffer(self, string):
         self.SetSelection(self.current_prompt_pos, self.GetLength())
         self.ReplaceSelection(string)
         self.GotoPos(self.GetLength())
 
     def _get_input_buffer(self):
         """ Returns the text in current edit buffer.
         """
         input_buffer = self.GetTextRange(self.current_prompt_pos,
                                                 self.GetLength())
         input_buffer = input_buffer.replace(LINESEP, '\n')
         return input_buffer
 
     input_buffer = property(_get_input_buffer, _set_input_buffer)
 
     style = _DEFAULT_STYLE.copy()
 
     # Translation table from ANSI escape sequences to color. Override
     # this to specify your colors.
     ANSI_STYLES = {'0;30': [0, 'BLACK'],            '0;31': [1, 'RED'],
                    '0;32': [2, 'GREEN'],            '0;33': [3, 'BROWN'],
                    '0;34': [4, 'BLUE'],             '0;35': [5, 'PURPLE'],
                    '0;36': [6, 'CYAN'],             '0;37': [7, 'LIGHT GREY'],
                    '1;30': [8, 'DARK GREY'],        '1;31': [9, 'RED'],
                    '1;32': [10, 'SEA GREEN'],       '1;33': [11, 'YELLOW'],
                    '1;34': [12, 'LIGHT BLUE'],      '1;35':
                                                      [13, 'MEDIUM VIOLET RED'],
                    '1;36': [14, 'LIGHT STEEL BLUE'], '1;37': [15, 'YELLOW']}
 
     # The color of the carret (call _apply_style() after setting)
     carret_color = 'BLACK'
     
     # Store the last time a refresh was done
     _last_refresh_time = 0
 
     #--------------------------------------------------------------------------
     # Public API
     #--------------------------------------------------------------------------
     
     def __init__(self, parent, id=wx.ID_ANY, pos=wx.DefaultPosition, 
                         size=wx.DefaultSize, style=wx.WANTS_CHARS, ):
         editwindow.EditWindow.__init__(self, parent, id, pos, size, style)
         self._configure_scintilla()
 
         self.Bind(wx.EVT_KEY_DOWN, self._on_key_down)
         self.Bind(wx.EVT_KEY_UP, self._on_key_up)
     
 
     def write(self, text, refresh=True):
         """ Write given text to buffer, while translating the ansi escape
             sequences.
         """
         # XXX: do not put print statements to sys.stdout/sys.stderr in 
         # this method, the print statements will call this method, as 
         # you will end up with an infinit loop
         title = self.title_pat.split(text)
         if len(title)>1:
             self.title = title[-2]
 
         text = self.title_pat.sub('', text)
         segments = self.color_pat.split(text)
         segment = segments.pop(0)
         self.GotoPos(self.GetLength())
         self.StartStyling(self.GetLength(), 0xFF)
         try:
             self.AppendText(segment)
         except UnicodeDecodeError:
             # XXX: Do I really want to skip the exception?
             pass
         
         if segments:
             for ansi_tag, text in zip(segments[::2], segments[1::2]):
                 self.StartStyling(self.GetLength(), 0xFF)
                 try:
                     self.AppendText(text)
                 except UnicodeDecodeError:
                     # XXX: Do I really want to skip the exception?
                     pass
 
                 if ansi_tag not in self.ANSI_STYLES:
                     style = 0
                 else:
                     style = self.ANSI_STYLES[ansi_tag][0]
 
                 self.SetStyling(len(text), style) 
                 
         self.GotoPos(self.GetLength())
         if refresh:
             current_time = time.time()
             if current_time - self._last_refresh_time > 0.03:
                 if sys.platform == 'win32':
                     wx.SafeYield()
                 else:
                     wx.Yield()
                 #    self.ProcessEvent(wx.PaintEvent())
                 self._last_refresh_time = current_time 
 
    
     def new_prompt(self, prompt):
         """ Prints a prompt at start of line, and move the start of the
             current block there.
 
             The prompt can be given with ascii escape sequences.
         """
         self.write(prompt, refresh=False)
         # now we update our cursor giving end of prompt
         self.current_prompt_pos = self.GetLength()
         self.current_prompt_line = self.GetCurrentLine()
         self.EnsureCaretVisible()
 
 
     def scroll_to_bottom(self):
         maxrange = self.GetScrollRange(wx.VERTICAL)
         self.ScrollLines(maxrange)
 
 
     def pop_completion(self, possibilities, offset=0):
         """ Pops up an autocompletion menu. Offset is the offset
             in characters of the position at which the menu should
             appear, relativ to the cursor.
         """
         self.AutoCompSetIgnoreCase(False)
         self.AutoCompSetAutoHide(False)
         self.AutoCompSetMaxHeight(len(possibilities))
         self.AutoCompShow(offset, " ".join(possibilities))
 
 
     def get_line_width(self):
         """ Return the width of the line in characters.
         """
         return self.GetSize()[0]/self.GetCharWidth()
 
 
     def clear_screen(self):
         """ Empty completely the widget.
         """
         self.ClearAll()
         self.new_prompt(self.input_prompt_template.substitute(
                                 number=(self.last_result['number'] + 1)))
 
 
 
     #--------------------------------------------------------------------------
     # EditWindow API
     #--------------------------------------------------------------------------
 
     def OnUpdateUI(self, event):
         """ Override the OnUpdateUI of the EditWindow class, to prevent 
             syntax highlighting both for faster redraw, and for more
             consistent look and feel.
         """
 
     #--------------------------------------------------------------------------
     # Private API
     #--------------------------------------------------------------------------
     
     def _apply_style(self):
         """ Applies the colors for the different text elements and the
             carret.
         """
         self.SetCaretForeground(self.carret_color)
 
         #self.StyleClearAll()
         self.StyleSetSpec(stc.STC_STYLE_BRACELIGHT,  
                           "fore:#FF0000,back:#0000FF,bold")
         self.StyleSetSpec(stc.STC_STYLE_BRACEBAD,
                           "fore:#000000,back:#FF0000,bold")
 
         for style in self.ANSI_STYLES.values():
             self.StyleSetSpec(style[0], "bold,fore:%s" % style[1])
 
    
     def _configure_scintilla(self):
         self.SetEOLMode(stc.STC_EOL_LF)
 
         # Ctrl"+" or Ctrl "-" can be used to zoomin/zoomout the text inside 
         # the widget
         self.CmdKeyAssign(ord('+'), stc.STC_SCMOD_CTRL, stc.STC_CMD_ZOOMIN)
         self.CmdKeyAssign(ord('-'), stc.STC_SCMOD_CTRL, stc.STC_CMD_ZOOMOUT)
         # Also allow Ctrl Shift "=" for poor non US keyboard users. 
         self.CmdKeyAssign(ord('='), stc.STC_SCMOD_CTRL|stc.STC_SCMOD_SHIFT, 
                                             stc.STC_CMD_ZOOMIN)
         
         # Keys: we need to clear some of the keys the that don't play
         # well with a console.
         self.CmdKeyClear(ord('D'), stc.STC_SCMOD_CTRL)
         self.CmdKeyClear(ord('L'), stc.STC_SCMOD_CTRL)
         self.CmdKeyClear(ord('T'), stc.STC_SCMOD_CTRL)
         self.CmdKeyClear(ord('A'), stc.STC_SCMOD_CTRL)
 
         self.SetEOLMode(stc.STC_EOL_CRLF)
         self.SetWrapMode(stc.STC_WRAP_CHAR)
         self.SetWrapMode(stc.STC_WRAP_WORD)
         self.SetBufferedDraw(True)
         self.SetUseAntiAliasing(True)
         self.SetLayoutCache(stc.STC_CACHE_PAGE)
         self.SetUndoCollection(False)
         self.SetUseTabs(True)
         self.SetIndent(4)
         self.SetTabWidth(4)
 
         # we don't want scintilla's autocompletion to choose 
         # automaticaly out of a single choice list, as we pop it up
         # automaticaly
         self.AutoCompSetChooseSingle(False)
         self.AutoCompSetMaxHeight(10)
         # XXX: this doesn't seem to have an effect.
         self.AutoCompSetFillUps('\n')
 
         self.SetMargins(3, 3) #text is moved away from border with 3px
         # Suppressing Scintilla margins
         self.SetMarginWidth(0, 0)
         self.SetMarginWidth(1, 0)
         self.SetMarginWidth(2, 0)
 
         self._apply_style()
 
         # Xterm escape sequences
         self.color_pat = re.compile('\x01?\x1b\[(.*?)m\x02?')
         self.title_pat = re.compile('\x1b]0;(.*?)\x07')
 
         #self.SetEdgeMode(stc.STC_EDGE_LINE)
         #self.SetEdgeColumn(80)
 
         # styles
         p = self.style
         self.StyleSetSpec(stc.STC_STYLE_DEFAULT, p['default'])
         self.StyleClearAll()
         self.StyleSetSpec(_STDOUT_STYLE, p['stdout'])
         self.StyleSetSpec(_STDERR_STYLE, p['stderr'])
         self.StyleSetSpec(_TRACE_STYLE, p['trace'])
 
         self.StyleSetSpec(stc.STC_STYLE_BRACELIGHT, p['bracegood'])
         self.StyleSetSpec(stc.STC_STYLE_BRACEBAD, p['bracebad'])
         self.StyleSetSpec(stc.STC_P_COMMENTLINE, p['comment'])
         self.StyleSetSpec(stc.STC_P_NUMBER, p['number'])
         self.StyleSetSpec(stc.STC_P_STRING, p['string'])
         self.StyleSetSpec(stc.STC_P_CHARACTER, p['char'])
         self.StyleSetSpec(stc.STC_P_WORD, p['keyword'])
         self.StyleSetSpec(stc.STC_P_WORD2, p['keyword'])
         self.StyleSetSpec(stc.STC_P_TRIPLE, p['triple'])
         self.StyleSetSpec(stc.STC_P_TRIPLEDOUBLE, p['tripledouble'])
         self.StyleSetSpec(stc.STC_P_CLASSNAME, p['class'])
         self.StyleSetSpec(stc.STC_P_DEFNAME, p['def'])
         self.StyleSetSpec(stc.STC_P_OPERATOR, p['operator'])
         self.StyleSetSpec(stc.STC_P_COMMENTBLOCK, p['comment'])
 
     def _on_key_down(self, event, skip=True):
         """ Key press callback used for correcting behavior for 
             console-like interfaces: the cursor is constraint to be after
             the last prompt.
 
             Return True if event as been catched.
         """
         catched = True
         # Intercept some specific keys.
         if event.KeyCode == ord('L') and event.ControlDown() :
             self.scroll_to_bottom()
         elif event.KeyCode == ord('K') and event.ControlDown() :
             self.input_buffer = ''
         elif event.KeyCode == ord('A') and event.ControlDown() :
             self.GotoPos(self.GetLength())
             self.SetSelectionStart(self.current_prompt_pos)
             self.SetSelectionEnd(self.GetCurrentPos())
             catched = True
         elif event.KeyCode == ord('E') and event.ControlDown() :
             self.GotoPos(self.GetLength())
             catched = True
         elif event.KeyCode == wx.WXK_PAGEUP:
             self.ScrollPages(-1)
         elif event.KeyCode == wx.WXK_PAGEDOWN:
             self.ScrollPages(1)
         elif event.KeyCode == wx.WXK_UP and event.ShiftDown():
             self.ScrollLines(-1)
         elif event.KeyCode == wx.WXK_DOWN and event.ShiftDown():
             self.ScrollLines(1)
         else:
             catched = False
 
         if self.AutoCompActive():
             event.Skip()
         else:
             if event.KeyCode in (13, wx.WXK_NUMPAD_ENTER) and \
                         event.Modifiers in (wx.MOD_NONE, wx.MOD_WIN):
                 catched = True
                 self.CallTipCancel()
                 self.write('\n', refresh=False)
                 # Under windows scintilla seems to be doing funny stuff to the 
                 # line returns here, but the getter for input_buffer filters 
                 # this out.
                 if sys.platform == 'win32':
                     self.input_buffer = self.input_buffer
                 self._on_enter()
 
             elif event.KeyCode == wx.WXK_HOME:
                 if event.Modifiers in (wx.MOD_NONE, wx.MOD_WIN):
                     self.GotoPos(self.current_prompt_pos)
                     catched = True
 
                 elif event.Modifiers == wx.MOD_SHIFT:
                     # FIXME: This behavior is not ideal: if the selection
                     # is already started, it will jump.
                     self.SetSelectionStart(self.current_prompt_pos) 
                     self.SetSelectionEnd(self.GetCurrentPos())
                     catched = True
 
             elif event.KeyCode == wx.WXK_UP:
                 if self.GetCurrentLine() > self.current_prompt_line:
                     if self.GetCurrentLine() == self.current_prompt_line + 1 \
                             and self.GetColumn(self.GetCurrentPos()) < \
                                 self.GetColumn(self.current_prompt_pos):
                         self.GotoPos(self.current_prompt_pos)
                     else:
                         event.Skip()
                 catched = True
 
             elif event.KeyCode in (wx.WXK_LEFT, wx.WXK_BACK):
-                if not self._keep_cursor_in_buffer():
+                if not self._keep_cursor_in_buffer(self.GetCurrentPos() - 1):
+                    event.Skip()
+                catched = True
+
+            elif event.KeyCode == wx.WXK_RIGHT:
+                if not self._keep_cursor_in_buffer(self.GetCurrentPos() + 1):
+                    event.Skip()
+                catched = True
+
+
+            elif event.KeyCode == wx.WXK_DELETE:
+                if not self._keep_cursor_in_buffer(self.GetCurrentPos() - 1):
                     event.Skip()
                 catched = True
 
             if skip and not catched:
                 # Put the cursor back in the edit region
                 if not self._keep_cursor_in_buffer():
-                    if (self.GetCurrentPos() == self.GetLength()
+                    if not (self.GetCurrentPos() == self.GetLength()
                                 and event.KeyCode == wx.WXK_DELETE):
-                        pass
-                    event.Skip()
+                        event.Skip()
+                    catched = True
 
         return catched
 
 
     def _on_key_up(self, event, skip=True):
         """ If cursor is outside the editing region, put it back.
         """
         if skip:
             event.Skip()
         self._keep_cursor_in_buffer()
 
 
-    def _keep_cursor_in_buffer(self):
+    def _keep_cursor_in_buffer(self, pos=None):
         """ Checks if the cursor is where it is allowed to be. If not,
             put it back.
 
             Returns
             -------
             cursor_moved: Boolean
                 whether or not the cursor was moved by this routine.
 
             Notes
             ------
                 WARNING: This does proper checks only for horizontal
                 movements.
         """
-        current_pos  = self.GetCurrentPos()
+        if pos is None:
+            current_pos = self.GetCurrentPos()
+        else:
+            current_pos = pos
         if  current_pos < self.current_prompt_pos:
             self.GotoPos(self.current_prompt_pos)
             return True
-        line, line_pos = self.GetCurLine()
+        line_num = self.LineFromPosition(current_pos)
+        if not current_pos > self.GetLength():
+            line_pos = self.GetColumn(current_pos)
+        else:
+            line_pos = self.GetColumn(self.GetLength())
+        line = self.GetLine(line_num)
         # Jump the continuation prompt
         continuation_prompt = self.continuation_prompt()
         if ( line.startswith(continuation_prompt)
                      and line_pos < len(continuation_prompt)+1):
             if line_pos < 2:
                 # We are at the beginning of the line, trying to move
                 # forward: jump forward.
                 self.GotoPos(current_pos + 1 +
                                     len(continuation_prompt) - line_pos)
             else:
                 # Jump back up
-                self.GotoPos(self.GetLineEndPosition(self.GetCurrentLine()-1))
+                self.GotoPos(self.GetLineEndPosition(line_num-1))
+            return True
+        elif ( current_pos > self.GetLineEndPosition(line_num) 
+                        and not current_pos == self.GetLength()): 
+            # Jump to next line
+            self.GotoPos(current_pos + 1 +
+                                    len(continuation_prompt))
             return True
         return False
 
 
 
 if __name__ == '__main__':
     # Some simple code to test the console widget.
     class MainWindow(wx.Frame):
         def __init__(self, parent, id, title):
             wx.Frame.__init__(self, parent, id, title, size=(300,250))
             self._sizer = wx.BoxSizer(wx.VERTICAL)
             self.console_widget = ConsoleWidget(self)
             self._sizer.Add(self.console_widget, 1, wx.EXPAND)
             self.SetSizer(self._sizer)
             self.SetAutoLayout(1)
             self.Show(True)
 
     app = wx.PySimpleApp()
     w = MainWindow(None, wx.ID_ANY, 'ConsoleWidget')
     w.SetSize((780, 460))
     w.Show()
 
     app.MainLoop()