Bazel cacheing of compilation / test failures?

user_1268551 0
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When compilation succeeds or a test passes, Bazel caches the result so if we repeat the build / test with the exact same code we get the result immediately.

That's great.

However, if the compilation fails - and I repeat the build with the exact same code - Bazel will attempt to recompile the code (and will fail again, with the exact same result)

Same for tests - if a test fails, and I rerun the test with the exact same code - Bazel will repeat the test.

Is there a way to tell Bazel to cache test / compilation failures as well as successes?

Usecase example:

  • I changed a lot of code in multiple files
  • I run bazel test //...:all
  • 100 tests run, 4 different tests fail
  • I fix the code of one of the tests and rerun bazel test //...:all
  • All the failing tests run again, even though 3 of the failing tests have no dependency change and there's no point rerunning them
  • I have to wait 4x longer than necessary for the tests to finish, and I'm sad :(

Something similar for the build failures. Sometimes a failed build can take many minutes to run on our codebase. If I rebuild without changing the files - it's a waste of time for bazel to rerun the failing build if it can use the cache...

bazel
1 Answers

I can see why this might be useful, but I'm not aware of a flag or other option that does something like this. At least in the case of a failing test, Bazel re-runs the failed test even if the inputs haven't changed to account for flaky tests. I suppose the same could be said for actions (a flaky compiler sounds pretty scary though). You might consider filing a feature request: https://github.com/bazelbuild/bazel/issues.

My advice would be to test only the specific target you're working on after running //...:all. You can also combine that with --test_filter to test only a specific test method within the test target.

user_63274450
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