Issue 22168: Turtle Graphics RawTurtle problem

Messages (5) msg225049 - (view) Author: Kent D. Lee (Kent.D..Lee) Date: 2014-08-08 01:27

This is either a turtle graphics or tkinter problem. 

In Python 3.4 it appears that something in Turtle Graphics broke or at least changed. I get the following error when trying to run a program that works in Python 3.1 and 3.2.

Kent's Mac> python3.4 c4.py
Traceback (most recent call last):
  File "c4.py", line 283, in <module>
    main()
  File "c4.py", line 277, in main
    animApp = Connect4Application(root)
  File "c4.py", line 110, in __init__
    self.buildWindow()
  File "c4.py", line 129, in buildWindow
    theTurtle = turtle.RawTurtle(canvas)
  File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/turtle.py", line 2534, in __init__
    self.screen = TurtleScreen(canvas)
  File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/turtle.py", line 1000, in __init__
    cv._rootwindow.call('wm', 'attributes', '.', '-topmost', '1')
AttributeError: 'Canvas' object has no attribute '_rootwindow'
Kent's Mac> 

The code is attached. The error occurs on line 129 when trying to create a RawTurtle and provide it with a Canvas.

msg225053 - (view) Author: Ned Deily (ned.deily) * Date: 2014-08-08 02:57

It looks like the changes associated with Issue11571, released in 3.4.1, cause this problem when the program supplies its own Canvas object rather than relying on the turtle module to create a default one.

msg225054 - (view) Author: Ned Deily (ned.deily) * Date: 2014-08-08 03:02

As a temporary workaround, you could edit turtle.py to revert that change, in other words, just search for and delete the whole "if sys.platform == 'darwin'" test:

diff -r d85fcf23549e Lib/turtle.py
--- a/Lib/turtle.py     Tue Aug 05 14:02:11 2014 -0500
+++ b/Lib/turtle.py     Thu Aug 07 19:58:25 2014 -0700
@@ -993,12 +993,6 @@
         self._colormode = _CFG["colormode"]
         self._keys = []
         self.clear()
-        if sys.platform == 'darwin':
-            # Force Turtle window to the front on OS X. This is needed because
-            # the Turtle window will show behind the Terminal window when you
-            # start the demo from the command line.
-            cv._rootwindow.call('wm', 'attributes', '.', '-topmost', '1')
-            cv._rootwindow.call('wm', 'attributes', '.', '-topmost', '0')

     def clear(self):
         """Delete all drawings and all turtles from the TurtleScreen.

The file is at /Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/turtle.py.

msg225776 - (view) Author: Ned Deily (ned.deily) * Date: 2014-08-24 00:47

The attached patch should prevent the AttributeError exception when not using a default Canvas.  I now think the overall approach introduced in Issue11571 is not the best.  I plan to commit this fix for now but encourage more robust solutions in the long term.

msg226863 - (view) Author: Ned Deily (ned.deily) * Date: 2014-09-14 07:05

The changesets below should prevent the problem in 3.4.2 and 3.5.0.  Since there are no standard tests for turtle at the moment, there is no testcase for using a non-default Canvas but one should be added when turtle tests are (Issue21914 and Issue21916). 

New changset fac17d06e01d by Ned Deily in branch '3.4':
Issue #22168: Prevent turtle AttributeError with non-default Canvas on OS X.
https://hg.python.org/cpython/rev/fac17d06e01d

New changeset 775453a7b85d by Ned Deily in branch 'default':
Issue #22168: Prevent turtle AttributeError with non-default Canvas on OS X.
https://hg.python.org/cpython/rev/775453a7b85d

History Date User Action Args 2014-09-14 07:05:33ned.deilysetstatus: open -> closed
resolution: fixed
messages: + msg226863

stage: patch review -> resolved

2014-08-24 00:47:02ned.deilysetfiles: + issue22168.patch
keywords: + patch
messages: + msg225776

stage: needs patch -> patch review

2014-08-08 03:02:42ned.deilysetmessages: + msg225054 2014-08-08 02:57:02ned.deilysetversions: + Python 3.5
nosy: + ned.deily

messages: + msg225053

assignee: ned.deily
stage: needs patch

2014-08-08 01:27:43Kent.D..Leecreate