CI: core dump errors

[kushaldas]

Example: https://circleci.com/gh/freedomofpress/securedrop-client/1163#usage-queue/containers/0

Found the cause below. Will examine more.

$ make test TESTS=tests/test_resources.py 
============================================================== test session starts ===============================================================
platform linux -- Python 3.5.7, pytest-3.9.3, py-1.7.0, pluggy-0.8.0 -- /home/circleci/project/.venv/bin/python
cachedir: .pytest_cache
Using --random-order-bucket=global
Using --random-order-seed=927124

rootdir: /home/circleci/project, inifile:
plugins: random-order-1.0.0, mock-1.10.0, cov-2.6.0
collected 5 items                                                                                                                                

tests/test_resources.py::test_load_css PASSED                                                                                              [ 20%]
tests/test_resources.py::test_path PASSED                                                                                                  [ 40%]
tests/test_resources.py::test_load_svg Aborted (core dumped)
make: *** [Makefile:35: test] Error 134

[kushaldas]

>>> def test_load_image():
...     """
...     Check the load_image function returns the expected QPixmap object.
...     """
...     result = securedrop_client.resources.load_image('icon')
...     assert isinstance(result, QPixmap)
... 
>>> test_load_image()
QPixmap: Must construct a QGuiApplication before a QPixmap
Aborted (core dumped)

[kushaldas]

I can now replicate locally.

$ make test TESTS=tests/test_resources.py 
============================================================== test session starts ===============================================================
platform linux -- Python 3.5.3, pytest-3.9.3, py-1.7.0, pluggy-0.8.0 -- /home/kdas/code/securedrop-client/.venv/bin/python
cachedir: .pytest_cache
Using --random-order-bucket=global
Using --random-order-seed=204513

rootdir: /home/kdas/code/securedrop-client, inifile:
plugins: random-order-1.0.0, mock-1.10.0, cov-2.6.0
collected 5 items                                                                                                                                

tests/test_resources.py::test_load_icon Aborted
Makefile:35: recipe for target 'test' failed
make: *** [test] Error 134