Print the configuration hash of failing tests

[cbarrete]

This mirrors the behavior of buck2 build.

Before:

3 TESTS FAILED
  ✗ root//:tests
  ✗ root//:tests
  ✗ root//:tests

After:

3 TESTS FAILED
  ✗ root//:tests (cfg:<empty>#bc315f4ba533984d)
  ✗ root//:tests (cfg:<empty>#da5b993178d15eca)
  ✗ root//:tests (cfg:<empty>#9251783cb051b3f7)

[meta-codesync]

This pull request has been imported. If you are a Meta employee, you can view this in D113167521. (Because this pull request was imported automatically, there will not be any future comments.)

[scottcao]

Review automatically exported from Phabricator review in Meta.

[8Keep]

@cbarrete I notice in your configuration hashes that you have printed have (cfg:<empty>#9251783cb051b3f7)

Do you know how to configure named configurations? I'm not sure if it's documented anywhere. You can have a set of constraints where you configure names so it can be more human friendly instead of just a hash, so you could have (cfg:linux-opt-clang-x86_64-etc#blahhashy) for the most useful constraints.

https://github.com/facebook/buck2/blob/main/prelude/cfg/modifier/name.bzl

[cbarrete]

1. I had no idea, thanks!
2. I'm pretty sure it's not documented
3. Unless I'm misreading the implementation, it (currently) only works with that hard coded list of constraint settings, no?

[8Keep]

Yes, it's probably hard coded

Would love a PR that makes it more usable for open source

[cbarrete]

I'm putting this in my todo list :)

[meta-codesync]

@8Keep merged this pull request in aa1cbe5.