#1149434 magicgui: FTBFS: SystemError: <method 'disconnect' of 'PySide6.QtCore.SignalInstance' objects> returned a result with an exception set

#1149434#5
Date:
2026-09-29 22:19:56 UTC
From:
To:
Dear maintainer:

During a rebuild of all packages in unstable, this package failed to build.

Below you will find the last part of the build log (probably the most
relevant part, but not necessarily). If required, the full build log
is available here:

https://people.debian.org/~sanvila/build-logs/202609/

About the archive rebuild: The build was made on virtual machines from AWS,
using sbuild and a reduced chroot with only build-essential packages.

If you cannot reproduce the bug please contact me privately, as I
am willing to provide ssh access to a virtual machine where the bug is
fully reproducible.

If this is really a bug in one of the build-depends, please use
reassign and add an affects on src:magicgui, so that this is still
visible in the BTS web page for this package.

Thanks.
--------------------------------------------------------------------------------
[...]
    ~~~~~~~~~~~~~~~~~^^^^^^
psygnal._exceptions.EmitLoopError:

While emitting signal 'magicgui.widgets._function_gui.FunctionGui.native_parent_changed', an error occurred in a callback:

  SystemError: <method 'disconnect' of 'PySide6.QtCore.SignalInstance' objects> returned a result with an exception set
  ---------------------------------------------------------------------------------------------------------------------

  SIGNAL EMISSION:
    /<<PKGBUILDDIR>>/.pybuild/cpython3_3.14_magicgui/build/tests/test_magicgui.py:501 in test_parent_changed
      magic_func.native.setParent(None)
    /<<PKGBUILDDIR>>/.pybuild/cpython3_3.14_magicgui/build/magicgui/backends/_qtpy/widgets.py:58 in eventFilter
      self.parentChanged.emit(obj.parent())  # <-- SIGNAL WAS EMITTED HERE

  CALLBACK CHAIN:
    src/psygnal/_signal.py:1311 in _run_emit_loop
    ... 5 more frames ...
    /usr/lib/python3/dist-packages/pytestqt/wait_signal.py:741 in _silent_disconnect
      signal.disconnect(slot)  # <-- ERROR OCCURRED HERE

#1149434#20
Date:
2026-10-02 04:58:48 UTC
From:
To:
 > SystemError: <method 'disconnect' of 'PySide6.QtCore.SignalInstance'
objects> returned a result with an exception set

I think this is fixed by the new version of pytest-qt - it doesn't
explicitly list supported Qt versions, but there are  upstream commits
regarding errors coming from `disconnect`. I've tested building and
autopkgtest-ing of both superqt and magicgui with python3-pytestqt
4.5.0-1 and they all succeed.

I've uploaded it to experimental. I'm hoping to get a bit of coverage
from ci.d.n for other architectures and it can then be uploaded the
unstable.

#1149434#31
Date:
2026-10-02 06:49:20 UTC
From:
To:
We believe that the bug you reported is fixed in the latest version of
pytest-qt, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1149293@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Stuart Prescott <stuart@debian.org> (supplier of updated pytest-qt package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Fri, 02 Oct 2026 16:22:06 +1000
Source: pytest-qt
Architecture: source
Version: 4.5.0-2
Distribution: unstable
Urgency: medium
Maintainer: Debian Python Team <team+python@tracker.debian.org>
Changed-By: Stuart Prescott <stuart@debian.org>
Closes: 1048340 1138115 1149293
Changes:
 pytest-qt (4.5.0-2) unstable; urgency=medium
 .
   * Upload to unstable.
   * Brings Qt 6.11 compatibility (for PySide6) (Closes: #1149293).
 .
 pytest-qt (4.5.0-1) experimental; urgency=medium
 .
   * New upstream release.
   * Remove Ghislain Vaillant from Uploaders, with thanks for previous
     contribution to maintenance of this package (Closes: #1138115).
   * Add myself to Uploaders.
   * Add additional egg-parts to d/clean (Closes: #1048340).
   * Update Standards-Version to 4.7.4 (no changes required).
   * Drop unneeded Priority:optional and R3:no fields.
   * Update d/watch to v5 format.
   * Run more of the test suite with different Qt bindings.
   * Add patch to permit test suite to run with multiple Qt bindings
     installed.
   * Run the tests without using Xvfb, using QT_QPA_PLATFORM=offscreen
     instead.
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 8a2e47dc585b330b8d78813f895ad16650eea19a 241332 pytest-qt_4.5.0-2.git.tar.xz
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Files:
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 42411b48898a8433b2b402e61a73d862 7740 python optional pytest-qt_4.5.0-2.debian.tar.xz
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Git-Tag-Info: tag=30d204fa462706fc58f596183df96a7632a1022e fp=90e2d2c1ad146a1b7ebb891dbbc17ebb1396f2f7
Git-Tag-Tagger: Stuart Prescott <stuart@debian.org>
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