"RuntimeError: Internal C++ object (PyDMShellCommand) already deleted" error occurs sometimes when running pyside6 tests

[nstelter-slac]

Describe the bug

The following occurs sometimes when running tests (python run_tests.py) with pyside6.
I've not seen this when running outside the tests, so not sure if pytest specific issue of indicative of actual pydm issue.

pydm/tests/widgets/test_waveform_plot.py::test_redrawPlot_without_crosshair Exceptions caught in Qt event loop:

---

Traceback (most recent call last):
File "/home/nolan_work/repos/pydm/pydm/widgets/shell_command.py", line 839, in
lambda: self._check_process_done(action, original_button_text, original_action_text)
~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/nolan_work/repos/pydm/pydm/widgets/shell_command.py", line 884, in _check_process_done
self.set_object_font_italic(self, False)
~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
File "/home/nolan_work/repos/pydm/pydm/widgets/shell_command.py", line 909, in set_object_font_italic
font = object.font()
RuntimeError: Internal C++ object (PyDMShellCommand) already deleted.

---

Exceptions caught in Qt event loop:

---

Traceback (most recent call last):
File "/home/nolan_work/repos/pydm/pydm/widgets/shell_command.py", line 839, in
lambda: self._check_process_done(action, original_button_text, original_action_text)
~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/nolan_work/repos/pydm/pydm/widgets/shell_command.py", line 884, in _check_process_done
self.set_object_font_italic(self, False)
~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
File "/home/nolan_work/repos/pydm/pydm/widgets/shell_command.py", line 909, in set_object_font_italic
font = object.font()
RuntimeError: Internal C++ object (PyDMShellCommand) already deleted.

---

FAILED

Steps to reproduce

1. create conda env with python 3.13 and pyside6:

  $ conda create -n pydm-environment-pyside python pip numpy scipy six psutil pyqtgraph pydm -c conda-forge
  $ source activate pydm-environment
  $ pip install PySide6 # or can install with conda in earlier cmd

2. edit run_tests.py to not run "test_psp_plugin_component.py" and "test_plugins_import.py"

--- a/run_tests.py
+++ b/run_tests.py
@@ -23,6 +23,8 @@ if __name__ == "__main__":
         args.append("--ignore=pydm/tests/data_plugins/test_p4p_plugin_component.py")
         args.append("--ignore=pydm/tests/data_plugins/test_psp_plugin_component.py")
 
+    args.append("--ignore=pydm/tests/data_plugins/test_psp_plugin_component.py")
+    args.append("--ignore=pydm/tests/test_plugins_import.py")
     print("pytest arguments: {}".format(args))
 
     sys.exit(pytest.main(args))

3. activate conda pyside6 env and export QT_API=pyside6

4. run python run_tests.py a few times until see the failure. (we should try do something to make this fail every-time for debugging)

Expected behavior

tests never hit this error.

Operating System.

Linux

OS Version Details.

No response

Python Version

Python 3.13.5

Packages Version

Additional context.

• I've seen this happen in other test-cases b4, but atm only get it from PyDMShellCommand
• Not sure if this could happen on pyqt5 also?
• This might be helpful: https://stackoverflow.com/questions/5339062/python-pyside-internal-c-object-already-deleted