bpo-6143: provides Clear Window option under options

Lib/idlelib/clearwindow.py

@@ -0,0 +1,110 @@
+##    Copyright(C) 2011-2012 The Board of Trustees of the University of Illinois.
+##    All rights reserved.
+##
+##    Developed by:   Roger D. Serwy
+##                    University of Illinois
+##
+##    Permission is hereby granted, free of charge, to any person obtaining
+##    a copy of this software and associated documentation files (the
+##    "Software"), to deal with the Software without restriction, including
+##    without limitation the rights to use, copy, modify, merge, publish,
+##    distribute, sublicense, and/or sell copies of the Software, and to
+##    permit persons to whom the Software is furnished to do so, subject to
+##    the following conditions:
+##
+##    + Redistributions of source code must retain the above copyright
+##      notice, this list of conditions and the following disclaimers.
+##    + Redistributions in binary form must reproduce the above copyright
+##      notice, this list of conditions and the following disclaimers in the
+##      documentation and/or other materials provided with the distribution.
+##    + Neither the names of Roger D. Serwy, the University of Illinois, nor
+##      the names of its contributors may be used to endorse or promote
+##      products derived from this Software without specific prior written
+##      permission.
+##
+##    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+##    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+##    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+##    IN NO EVENT SHALL THE CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR
+##    ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+##    CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH
+##    THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE SOFTWARE.
+
+import re
+from idlelib.undo import DeleteCommand
+
+jn = lambda x,y: '%i.%i' % (x,y)        # join integers to text coordinates
+sp = lambda x: tuple(map(int, x.split('.')))   # convert tkinter Text coordinate to a line and column tuple
+ansi_re = re.compile(r'\x01?\x1b\[(.*?)m\x02?')
+def strip_ansi(s):
+    return ansi_re.sub("", s)
+
+class clearwindow:
+    def __init__(self, editwin):
+        self.editwin = editwin
+
+    def clear_window_event(self, ev=None):
+        self.clear_window(ev)
+        return "break"
+
+    def clear_window(self, event):
+
+        per = self.editwin.per
+        text = per.bottom
+
+        iomark_orig = text.index('iomark')
+        line_io, col_io = sp(iomark_orig)
+
+        # if cursor is at the prompt, preserve the prompt (multiline)
+        prompt = strip_ansi(">>> ")
+        backlines = prompt.count('\n')
+        prompt_start = jn(line_io-backlines, 0)
+        maybe_prompt = text.get(prompt_start, prompt_start + '+%ic' % len(prompt))
+        at_prompt = maybe_prompt == prompt
+
+        if at_prompt:
+            endpos = text.index(prompt_start)
+        else:
+            endpos = text.index('iomark linestart')
+
+        dump = text.dump('1.0', endpos, all=True)
+
+        # Add a command to the undo delegator
+        undo = self.editwin.undo
+        if undo:
+            dc = clearwindowdeletecommand('1.0', endpos, dump)
+            undo.addcmd(dc)
+
+        text.edit_reset() # clear out Tkinter's undo history
+
+
+class clearwindowdeletecommand(DeleteCommand):
+    def __init__(self, index1, index2, dump):
+        DeleteCommand.__init__(self, index1, index2)
+        self.dump = dump
+
+    def do(self, text):
+        text.delete(self.index1, self.index2)
+        text.see('insert')
+
+    def redo(self, text):
+        text.delete(self.index1, self.index2)
+        text.see('insert')
+
+    def undo(self, text):
+        # inspired by "Serializing a text widget" at http://wiki.tcl.tk/9167
+        dump = self.dump
+        tag = {} # remember the index where a tag was activated
+        for key, value, index in dump:
+            if key == 'text':
+                text.insert(index, value, '')
+            elif key == 'tagon':
+                tag[value] = index
+            elif key == 'tagoff':
+                text.tag_add(value, tag[value], index)
+                del tag[value]
+        # extend existing tags to the end position
+        for value in tag:
+            text.tag_add(value, tag[value], self.index2)
+        text.see('insert')
+

Lib/idlelib/mainmenu.py

@@ -98,7 +98,7 @@
 
  ('options', [
    ('Configure _IDLE', '<<open-config-dialog>>'),
-   None,
+   ("Clear Window", "<<clear-window>>"),
    ('Show _Code Context', '<<toggle-code-context>>'),
    ('Show _Line Numbers', '<<toggle-line-numbers>>'),
    ('_Zoom Height', '<<zoom-height>>'),

Lib/idlelib/pyshell.py

@@ -843,6 +843,7 @@ def display_executing_dialog(self):
 
 class PyShell(OutputWindow):
     from idlelib.squeezer import Squeezer
+    from idlelib.clearwindow import clearwindow
 
     shell_title = "IDLE Shell " + python_version()
 
@@ -917,6 +918,8 @@ def __init__(self, flist=None):
             text.bind("<<view-restart>>", self.view_restart_mark)
             text.bind("<<restart-shell>>", self.restart_shell)
         self.squeezer = self.Squeezer(self)
+        self.ClearWindow = self.clearwindow(self)
+        text.bind("<<clear-window>>", self.clear_window)
         text.bind("<<squeeze-current-text>>",
                   self.squeeze_current_text_event)
 
@@ -1447,6 +1450,9 @@ def squeeze_current_text_event(self, event=None):
         self.squeezer.squeeze_current_text()
         self.shell_sidebar.update_sidebar()
 
+    def clear_window(self, event):
+        self.ClearWindow.clear_window_event()
+
     def on_squeezed_expand(self, index, text, tags):
         self.shell_sidebar.update_sidebar()