Is there a reason our tests didn't catch this? We do run the examples in the test suite, pretty sure.

Our test site runs the examples, but not the example application funny enough.

Should I look to add launching the example application as part of the test suite?

Also that CI failure, I am able to intermittently reproduce locally, but not reliably.

Been thinking, I think using hasattr is the wrong way to go about this, I should check with if QT_LIB in ['PyQt4', 'PySide']: which is how the rest of the library does it... will update the PR ...I'll see about adding the example app to the test suite as well.

Hmm getting the example app to run as part of the test suite is tricky haha

@ksunden can you think of a way we can add the example app as part of the test suite? I just added it to https://github.com/pyqtgraph/pyqtgraph/blob/master/examples/utils.py#L93 where instead of files = [] to files = [("Example App", "__main__.py")] but that just ran successfully (When it should have blown up).

whoops, accidentally pushed the wrong commit; going to put this in draft commit form until ready...

While this branch now works for having the example application launch on Python2 successfully, I want to try and minimize the warnings on python3 when launching the application, specifically....

/Users/ogi/.zinit/plugins/pyenv---pyenv/versions/3.8.3/Python.framework/Versions/3.8/lib/python3.8/runpy.py:127: RuntimeWarning: 'pyqtgraph.examples.__main__' found in sys.modules after import of package 'pyqtgraph.examples', but prior to execution of 'pyqtgraph.examples.__main__'; this may result in unpredictable behaviour
  warn(RuntimeWarning(msg))
qt.qpa.fonts: Populating font family aliases took 291 ms. Replace uses of missing font family "FreeMono" with one that exists to avoid this cost.

I get this warning when launching examples via python -m pyqtgraph.examples, but I do not get it when running

import pyqtgraph.examples
pyqtgraph.examples.run()

or

$ python examples

EDIT:

lastly, when installing pyqtgraph in editable mode, running python -m pyqtgraph.examples (from not within the git repo) will not run.

Scary warning no longer comes up; still want python -m pyqtgraph.examples to work when installing in editable mode (pip install -e .) as well as the font warning:

qt.qpa.fonts: Populating font family aliases took 299 ms. Replace uses of missing font family "FreeMono" with one that exists to avoid this cost.

Apparently running examples in editable mode is related to a long-standing setuptools issue: pypa/setuptools#230

We can work around this by changing the directory structure, but I don't think we actually want to do that for the additional functionality... last issue is fixing the font warning...

Switched font family to Courier New, which is available everywhere by default, had to regenerate the uic templates (always annoying)...

Did last bit of code cleanup, I think this PR is ready for merging.

just kidding, still not ready for merging, test app didn't actually get run...

ok, now the test application is tested as part of the test suite.

ok now that docs/CI and so on work, I think I'll just merge this guy...