Fatal Python Error When Running Pytest With Qt

I'm new to pytest and I'm having trouble trying to run one of my test files. I'm getting the following output: ================================================== test session star

Solution 1:

I had this issue today as well. The solution for me was to create a pytest.ini file in my tests directory and include this in it.

[pytest]qt_api=pyqt5

From https://github.com/pytest-dev/pytest-qt

To force a particular API, set the configuration variable qt_api in your pytest.ini file to pyqt5 or pyside2

Once I set the qt_api in the pytest.ini the tests ran without any issues

Solution 2:

I recognize this output, i had the same problem myself just recently

The problem was that i had forgotten to create the QApplication before creating the widget/window i wanted to test

So one way to solve the problem is this:

def test_something():
    test_app = QtWidgets.QApplication(sys.argv)  # <-----
    main_win = some_application.main_window.MainWindow()
    [...]

---

Alternatively you can use a pytest fixture which takes care of setup/teardown

pytest-qt includes the qtbot fixture. From the project readme file:

The main usage is to use the qtbot fixture, responsible for handling qApp creation as needed [...]

So in that case this is enough:

deftest_something(qtbot):  # <-----
    main_win = some_application.main_window.MainWindow()
    [...]

Solution 3:

In my case I ran into the Fatal Python error: aborted message, but it turned out to be due to my environment.

I was seeing failures running the test suite in GitHub Codespaces but when I went the extra step of cloning it, the suite worked under Crostini on my Chromebook. Once I realized that it worked where I had a DISPLAY variable defined I realized that the Qt tests probably required a DISPLAY, whether xvfb or a "real" display, so I installed xvfb and then used xvfb-run pytest -v and was able to see the test suite succeed.