Why doesn't --stepwise work?

[jcoombes]

the corresponding config file is in the cache, but it doesn't actually work to start from the last failed test.

[The-Compiler]

I'm not sure how you expect any useful answer with zero information. Ideally, you'd show some sort of minimal example and a terminal session showing what "doesn't work" entails exactly.

[graingert]

Ah sorry about the lack of debug information, I saw this issue with my own eyes on a voice chat and asked @jcoombes to raise the discussion, but I'm not exactly sure where to begin with collecting information to debug this one.

It's also intermittent, and I can't repeat it on my identical hardware and identical pytest configuration and virtual environment

[nicoddemus]

If you can at least provide the steps and outputs we might be able to guess what might be going on.

For example, --stepwise expects stable node ids, if the tests are parametrized and the values are randomized on each run, then --stepwise cannot work because the node ids would change between runs.