More verbose tracebacks on exceptions in event loop

[Czaki]

When an exception happens during the event loop, only a tight traceback is printed.

  File "D:\tmp\tox\py39-PyQt5-all\lib\site-packages\napari\utils\events\containers\_evented_list.py", line 195, in insert
      self.events.inserted(index=index, value=value)
    File "D:\tmp\tox\py39-PyQt5-all\lib\site-packages\napari\utils\events\event.py", line 763, in __call__
      self._invoke_callback(cb, event if pass_event else None)
    File "D:\tmp\tox\py39-PyQt5-all\lib\site-packages\napari\utils\events\event.py", line 801, in _invoke_callback
      _handle_exception(
    File "D:\tmp\tox\py39-PyQt5-all\lib\site-packages\napari\utils\events\event.py", line 788, in _invoke_callback
      cb(event)

But it is often not very helpful to debug.

pytest support rich tracebacks https://docs.pytest.org/en/7.1.x/how-to/output.html#modifying-python-traceback-printing

Will you accept PR with such enhancement?

[nicoddemus]

Hi @Czaki,

Yeah that sounds interesting, specially if the code for it is simple and uses only public APIs, which from the top of my head seems possible. Feel free to give this a go, thanks. 👍