Skip to content

Tk 8.6.0 introduces TypeError. (Tk 8.5.13 works) #61013

Closed
Closed
Tk 8.6.0 introduces TypeError. (Tk 8.5.13 works)#61013
Assignees
serhiy-storchaka
Labels
topic-tkintertype-bugAn unexpected behavior, bug, or error

Description

@serwy
serwy
mannequin
opened on Dec 29, 2012
BPO 16809
Nosy @serwy, @vadmium, @serhiy-storchaka, @floppym
Dependencies
  • bpo-18101: Tk.split() doesn't work with nested Unicode strings
    		•
    Files
  • tk_86_error.py
  • tk_86_workaround.py
  • tkinter_no_tcl_obj.patch: Switch off Tcl_Obj
  • tkinter_split.patch: Tk.splitline() and Tk.split() work with Tcl_Obj
    		•

    Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.

    Show more details

    GitHub fields:

    assignee = 'https://github.com/serhiy-storchaka'
closed_at = <Date 2013-10-27.10:46:32.859>
created_at = <Date 2012-12-29.06:38:27.407>
labels = ['type-bug', 'expert-tkinter']
title = 'Tk 8.6.0 introduces TypeError. (Tk 8.5.13 works)'
updated_at = <Date 2013-10-27.10:46:32.857>
user = 'https://github.com/serwy'

    bugs.python.org fields:

    activity = <Date 2013-10-27.10:46:32.857>
actor = 'serhiy.storchaka'
assignee = 'serhiy.storchaka'
closed = True
closed_date = <Date 2013-10-27.10:46:32.859>
closer = 'serhiy.storchaka'
components = ['Tkinter']
creation = <Date 2012-12-29.06:38:27.407>
creator = 'roger.serwy'
dependencies = ['18101']
files = ['28476', '30421', '30428', '30429']
hgrepos = []
issue_num = 16809
keywords = ['patch']
message_count = 16.0
messages = ['178475', '178720', '178729', '178757', '184624', '184840', '190336', '190360', '190362', '190363', '192062', '193586', '195899', '195901', '195902', '201445']
nosy_count = 8.0
nosy_names = ['gpolo', 'roger.serwy', 'Arfrever', 'python-dev', 'martin.panter', 'serhiy.storchaka', 'floppymaster', 'alejandroautalan']
pr_nums = []
priority = 'critical'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue16809'
versions = ['Python 2.7', 'Python 3.3', 'Python 3.4']

    Activity

    1. serwy commented on Dec 29, 2012

      @serwy
      serwymannequin
      on Dec 29, 2012
      MannequinAuthor

      I am running Arch Linux with the latest Tcl/Tk 8.6.0 build with Python 2.7.3 and 3.3.0, and the latest 3.4.0a0 build from the repository.

      Running the attached script fails when calling pack_info(). Here's is the script's output:

      8.6
Traceback (most recent call last):
  File "tk_86_error.py", line 6, in <module>
    label.pack_info()
  File "/usr/lib/python3.3/tkinter/__init__.py", line 1884, in pack_info
    self.tk.call('pack', 'info', self._w))
TypeError: Can't convert '_tkinter.Tcl_Obj' object to str implicitly

      This error did not occur when using Tk 8.5.13.

    2. serwy
      added
      topic-tkinter
      type-bugAn unexpected behavior, bug, or error
      on Dec 29, 2012

    3. serwy commented on Dec 31, 2012

      @serwy
      serwymannequin
      on Dec 31, 2012
      MannequinAuthor

      In Objects/unicodeobject.c in PyUnicode_FromObject, the call to PyUnicode_CheckExact fails when using 8.6.0 but works with 8.5.13.

    4. serhiy-storchaka commented on Jan 1, 2013

      @serhiy-storchaka
      serhiy-storchaka
      on Jan 1, 2013
      Member

      I don't install Tcl/Tk 8.6 yet, but looks as "pack info" call returns a new type of Tcl data (perhaps DictType) which doesn't detected in FromObj().

    5. serhiy-storchaka commented on Jan 1, 2013

      @serhiy-storchaka
      serhiy-storchaka
      on Jan 1, 2013
      Member

      The simplest fix probably is just wrap self.tk.call() with str() (I have not tested it yet). However the problem is more serious (tkinter doesn't support fully even 8.5 and subtle bugs are possible) and I'll spend some more time on its research.

    6. serhiy-storchaka
      self-assigned this
      on Jan 1, 2013

    7. serhiy-storchaka commented on Mar 19, 2013

      @serhiy-storchaka
      serhiy-storchaka
      on Mar 19, 2013
      Member

      Here is a patch which add support of Tcl_Obj to tkinter's splitlist(). This not only fixes some incompatibility with Tk 8.6, but can fix some issues with older Tk versions (see for example bpo-17397).

    8. serwy commented on Mar 21, 2013

      @serwy
      serwymannequin
      on Mar 21, 2013
      MannequinAuthor

      Serhiy, I applied your patch but I still get the same error.

      From what I have found so far, the FromObj function in Modules/_tkinter.c relies on cached values for different Tcl_ObjType, as given in the TkappObject struct. From the comment:

      /* We cannot include tclInt.h, as this is internal.
   So we cache interesting types here. */

      I haven't traced down the exact difference between 8.5 and 8.6 that causes the existing cached types to not match. The correct behavior from 8.5 is a match to "StringType". I've noticed a lot more macros in the 8.6 headers than in 8.5 which may be the culprit.

    9. serwy commented on May 30, 2013

      @serwy
      serwymannequin
      on May 30, 2013
      MannequinAuthor

      The problem I'm encountering is that tk.splitlist() is now being given a Tcl_Obj instead of a "str" type. Since everything is Tcl is a string, explicitly casting a Tcl_Obj to a string seems reasonable. Attached is some proof-of-concept code to work around the issue.

      Serhiy's patch against 3.4 gives this traceback:

      [python@saturn 3.4]$ ./python tk_86_error.py 
8.6
Traceback (most recent call last):
  File "tk_86_error.py", line 6, in <module>
    label.pack_info()
  File "/home/python/python/3.4/Lib/tkinter/__init__.py", line 1924, in pack_info
    if value[:1] == '.':
TypeError: '_tkinter.Tcl_Obj' object is not subscriptable

    10. serhiy-storchaka commented on May 30, 2013

      @serhiy-storchaka
      serhiy-storchaka
      on May 30, 2013
      Member

      Yes, I considered this option. A sure way to get rid of this and future changes in Tcl types, is get rid of Tcl_Obj at all and always return strings (if it is not a number or list). The drawback of this method is that occurs unnecessary conversion between Tcl and Python types and that information about types is lost. Also it is possible to hamper support for new Tcl types (dict, StateSpec, etc) in future.

      Another way is much more difficult. We need to allow all Tkinter functions to accept Tcl_Obj. Unfortunately this doesn't solve the problem fully because other code might expect a string instead of Tcl_Obj. We don't have enough test coverage to verify that the changes are sufficient. In any case, there are third-party code, which will also have to change to support the new Tcl versions.

    11. serhiy-storchaka commented on May 30, 2013

      @serhiy-storchaka
      serhiy-storchaka
      on May 30, 2013
      Member

      Here are a patch which quickly switch off Tcl_Obj.

    12. serhiy-storchaka commented on May 30, 2013

      @serhiy-storchaka
      serhiy-storchaka
      on May 30, 2013
      Member

      And here is a patch which allows Tk.splitline() and Tk.split() to work with Tcl_Obj. It also includes some other minor fixes to support Tcl 8.6. The patch includes a fix for bpo-18101.

    13. Arfrever commented on Jun 30, 2013

      @Arfrever
      Arfrevermannequin
      on Jun 30, 2013
      Mannequin

      Please commit the full patch in all active branches.

    14. alejandroautalan commented on Jul 23, 2013

      @alejandroautalan
      alejandroautalanmannequin
      on Jul 23, 2013
      Mannequin

      Hello.
      I tried 'tkinter_split.patch' patch against 3.3.2, but a fix for grid_info function is also needed.

      #test.py
import tkinter as tk

root = tk.Tk()
b = tk.Button(root, text='Button')
b.grid()
print(b.grid_info())
root.mainloop()

      Here's is the script's output:

      alejandro@vostro1:~/tmp$ cpython3.3 test.py 
Traceback (most recent call last):
  File "test.py", line 10, in <module>
    print(b.grid_info())
  File "/home/alejandro/apps/cpython3.3.2/lib/python3.3/tkinter/__init__.py", line 2024, in grid_info
    if value[:1] == '.':
TypeError: '_tkinter.Tcl_Obj' object is not subscriptable

    15. python-dev commented on Aug 22, 2013

      @python-dev
      python-devmannequin
      on Aug 22, 2013
      Mannequin

      New changeset 6b841e1ee3b8 by Serhiy Storchaka in branch '3.3':
      Issue bpo-16809: Tkinter's splitlist() and split() methods now accept Tcl_Obj
      http://hg.python.org/cpython/rev/6b841e1ee3b8

      New changeset 85285e6e28f4 by Serhiy Storchaka in branch 'default':
      Issue bpo-16809: Tkinter's splitlist() and split() methods now accept Tcl_Obj
      http://hg.python.org/cpython/rev/85285e6e28f4

      New changeset 2d96764a66fa by Serhiy Storchaka in branch '2.7':
      Issue bpo-16809: Tkinter's splitlist() and split() methods now accept Tcl_Obj
      http://hg.python.org/cpython/rev/2d96764a66fa

    16. python-dev commented on Aug 22, 2013

      @python-dev
      python-devmannequin
      on Aug 22, 2013
      Mannequin

      New changeset 516b0cd87a90 by Serhiy Storchaka in branch '3.3':
      Issue bpo-16809: Fixed some tkinter incompabilities with Tcl/Tk 8.6.
      http://hg.python.org/cpython/rev/516b0cd87a90

      New changeset 5b5ef012cd4e by Serhiy Storchaka in branch 'default':
      Issue bpo-16809: Fixed some tkinter incompabilities with Tcl/Tk 8.6.
      http://hg.python.org/cpython/rev/5b5ef012cd4e

      New changeset 06244031b608 by Serhiy Storchaka in branch '2.7':
      Issue bpo-16809: Fixed some tkinter incompabilities with Tcl/Tk 8.6.
      http://hg.python.org/cpython/rev/06244031b608

    17. serhiy-storchaka commented on Aug 22, 2013

      @serhiy-storchaka
      serhiy-storchaka
      on Aug 22, 2013
      Member

      Thank you alejandro. Fixed.

      I'm afraid this is not all problems with 8.6 and so left this issue open.

    18. serhiy-storchaka commented on Oct 27, 2013

      @serhiy-storchaka
      serhiy-storchaka
      on Oct 27, 2013
      Member

      Since there are no other reports about 8.6 I close this issue.

    19. serhiy-storchaka
      closed this as completedon Oct 27, 2013
    20. ezio-melotti
      transferred this issue fromon Apr 10, 2022
    Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

    Metadata

    Metadata

    Assignees

    Labels

    topic-tkintertype-bugAn unexpected behavior, bug, or error

    Projects

    No projects

      Milestone

      No milestone

      Relationships

      None yet

      Development

      No branches or pull requests

      Issue actions