Coverage plugin broken with coverage.py 5.x #3515
Description
Coverage reporting using the Cython plugin does not work for the 5.x series of coverage.py. For example, attempting to run coverage tests on raysect produces errors:
python setup.py build_ext -j4 --inplace --line-profile
coverage run -m unittest discoverOutput:
...................................................................................................................................................................................................................................................................................................................................................................................................................................................
----------------------------------------------------------------------
Ran 435 tests in 2.122s
OK
Can't add file tracer data for unmeasured file '/home/jlovell/FUN/cherab/raysect/raysect/core/math/_vec3.pxd'
Attempting to produce HTML output also results in an error:
coverage htmlOutput:
Couldn't parse '/home/jlovell/FUN/cherab/raysect/raysect/core/acceleration/accelerator.pyx' as Python source: 'invalid syntax' at line 32
Using coverage.py 4.5 on the same set of build files results in no errors reported about pyx files, and the HTML output is produced successfully.