[CI - test_optimizer] GitHub Actions, Melos, very_good test lead sometimes to cache error

[Max Weber]

Description
We use GitHub Actions with the caching support of the subosito/flutter-action@v2 together with Melos and every now and then we run into the following error:

cache/bundled/test_optimizer_0.1.0+1_e324e538d331470906db7fbaea6b8d957bcce68d/hooks/build/hooks/pre_gen/pre_gen_7389adb0f4462262bdd04123d3826c0231f89ed6.dart': No such file or directory

Melos config looks like this:

  ci:test:
    run: |
      melos exec -c 4 -- \
        very_good test --coverage --test-randomize-ordering-seed random

Steps To Reproduce

• Create a minimal project with melos multiple packages
• Add a CI with GitHub Actions
• Run very_good test with 4 concurrencies via melos in all packages

Expected Behavior
No error

Additional Context
I know that is not a perfect issue, but any help is much appreciated.

[Tom Arra]

Hi @md-weber 👋 Thanks for opening up an issue.

Would you be able to provide a sample project that can clearly demonstrate this? We don't tend to work with a lot of projects using Melos so want to make sure we are not spinning our wheels or trying something different then what your putting together. One other thing to ask is if you have tried this without the concurrency flag. We have seen some issues with that in the past and would like to be able to rule that out quickly if possible.

Thanks in advance and looking forward to your reply.

[Max Weber]

Hi @tomarra thanks for your answer, I will work on a demo example this weekend and hope that I can provide you an example till next week.

At the moment we did exactly that to at least not see the warning anymore. As soon the concurrency is out, it works flawless. If that just mean we cannot use concurrency in Melos it is still good to have that issue so that people know about it 👍