Tkinter, IDLE: Future Tcl and Tk can have differing version/patchlevel

[chrstphrchvz]

Tk 8.7 will be compatible with both Tcl 8.7 and Tcl 9.0; there is no Tk 9.0 currently in development. The version and/or patchlevel of Tcl and Tk will not necessarily be identical, but there are places in Tkinter code which assume they are. A few examples which I am aware of:

cpython/Lib/idlelib/help_about.py

Line 79 in 48b3617

tk_patchlevel = self.info_patchlevel()

cpython/Lib/test/test_tkinter/support.py

Line 103 in 48b3617

_tk_patchlevel = tcl.info_patchlevel()

cpython/Lib/test/test_tcl.py

Line 28 in 48b3617

_tk_patchlevel = tcl.info_patchlevel()

Linked PRs

• gh-104496: IDLE - fix About for mixed tcl/tk versions #104585
• [3.11] gh-104496: IDLE - fix About for mixed tcl/tk versions (GH-104585) #104587
• gh-104496: Use correct Tcl or Tk version in Tkinter tests #107688
• [3.12] gh-104496: Use correct Tcl or Tk version in Tkinter tests (GH-107688) #107709
• [3.11] gh-104496: Use correct Tcl or Tk version in Tkinter tests (GH-107688) #107719

[terryjreedy]

Is there different code to get tk version/patchlevel?

[chrstphrchvz]

Tcl version: tkinter.Tcl().tk.call('info', 'tclversion') and tkinter.Tcl().globalgetvar('tcl_version')
Tcl patchlevel: tkinter.Tcl().tk.call('info', 'patchlevel') and tkinter.Tcl().globalgetvar('tcl_patchLevel')
Tk version: tkinter.Tk().globalgetvar('tk_version')
Tk patchlevel: tkinter.Tk().globalgetvar('tk_patchLevel')

This issue is likely more applicable to version checks which need to be added (e.g. for issues like #104497) rather than existing ones (since checking for Tcl 8.6 is sufficient for knowing e.g. whether Tk has PNG support).

For this issue, I am less inclined to propose a solution on my own without prior input. I hesitate to introduce more ways to retrieve the version/patchlevel. Personally, I try to rely on the Tcl package vcompare command rather than retrieve/expose the version/patchlevel and attempt to reimplement correct version comparison logic in Python or Perl.

[terryjreedy]

https://github.com/python/cpython/blob/48b3617de491f00a3bf978b355074cc8e228d61b/Lib/tkinter/__init__.py#LL1081C1-L1084C1 has the following, which includes all 'patchlevel' occurrences in the file.

    def info_patchlevel(self):  # Method of Misc, a base for toplevel and widgets. [comment added]
        """Returns the exact version of the Tcl library."""
        patchlevel = self.tk.call('info', 'patchlevel')
        return _parse_version(patchlevel)

Is this call, the one that IDLE currently uses, returning the tcl or tk version?

[chrstphrchvz]

https://github.com/python/cpython/blob/48b3617de491f00a3bf978b355074cc8e228d61b/Lib/tkinter/__init__.py#LL1081C1-L1084C1 has the following, which includes all 'patchlevel' occurrences in the file.

    def info_patchlevel(self):  # Method of Misc, a base for toplevel and widgets. [comment added]
        """Returns the exact version of the Tcl library."""
        patchlevel = self.tk.call('info', 'patchlevel')
        return _parse_version(patchlevel)

Is this call, the one that IDLE currently uses, returning the tcl or tk version?

This always returns the Tcl patchlevel.