Note: codecov is wrong that is pointing to a problem with the CI's coverage calculations. Perhaps that can be addressed in another PR.

Originally posted by @anilbey in #2830 (comment)

A codecov report: https://app.codecov.io/gh/neuronsimulator/nrn/pull/2830/blob/share/lib/python/neuron/tests/test_neuron.py

Either those tests are executed but their coverage is not reported or (worse) those tests are not executed in CI run.