Tkinter: Tk 8.7 quotes pathnames in certain error messages

[chrstphrchvz]

Tk 8.7 (as of https://core.tcl-lang.org/tk/info/2991150c09f6) adds quotes around window pathnames in a few error messages, including those triggered by two Tkinter tests, causing them to fail:

======================================================================
FAIL: test_pack_configure_in (test.test_tkinter.test_geometry_managers.PackTest.test_pack_configure_in)
----------------------------------------------------------------------
_tkinter.TclError: can't pack ".pack.a" inside itself

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/user/git/cpython/Lib/test/test_tkinter/test_geometry_managers.py", line 111, in test_pack_configure_in
    with self.assertRaisesRegex(TclError,
AssertionError: "can't pack .pack.a inside itself" does not match "can't pack ".pack.a" inside itself"

======================================================================
FAIL: test_place_configure_in (test.test_tkinter.test_geometry_managers.PlaceTest.test_place_configure_in)
----------------------------------------------------------------------
_tkinter.TclError: can't place ".!toplevel2.!frame2" relative to itself

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/user/git/cpython/Lib/test/test_tkinter/test_geometry_managers.py", line 295, in test_place_configure_in
    with self.assertRaisesRegex(TclError, "can't place %s relative to "
AssertionError: "can't place \.!toplevel2\.!frame2 relative to itself" does not match "can't place ".!toplevel2.!frame2" relative to itself"

Linked PRs

• gh-104494: Update certain Tkinter pack/place tests for Tk 8.7 errors #104495
• [3.11] gh-104494: Update certain Tkinter pack/place tests for Tk 8.7 errors (GH-104495) #104569

[terryjreedy]

I have asked on the triager-coredev discord whether these prevent-future-bug issues should be considered enhancements or bugfixes (and eligible to be backported). Even if we decide not an issue for 3.11, this will matter soon for 3.12, when 3.12.0b1 is released (a week?) and 'main' becomes the future 3.13.0.

[erlend-aasland]

Adjusting tests for Tk 8.7 compatibility is fine. This happens for other extension modules with third party deps as well (for example the sqlite3 module). I'd be fine to backport the test adjustments to 3.11. (3.10 is out of the question, since it only accepts security fixes).

[terryjreedy]

Some of the adjustments will be to _tkinter or tkinter code, not tests. Example in
#104496.

[terryjreedy]

I now agree that we should backport all tests. See new tracking issue #104568. Will immediately backport the PR here.