[PATCH] D70105: [lit] Better/earlier errors for empty runs

[Joel E. Denny via Phabricator via llvm-commits]

jdenny added a comment.

> The number of shards is greater than the number of tests. Currently, this is never an error. Personally, I think we should consider making this an error by default; if this happens, you are doing something wrong. I added a warning but did not change the behavior, since this warrants more discussion.

I haven't used shards much, so I don't know what use cases are relevant.

My guess is that `LIT_FILTER` would be a reason why you might end up with more shards than tests: you already have some distributed test run configuration with shards, and you temporarily add `LIT_FILTER` to focus on specific failing tests.  It seems reasonable that `--allow-empty-runs` would again suppress the error.  I don't know whether this use case arises in practice.

Thanks for working on all this.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D70105/new/

https://reviews.llvm.org/D70105