Clean up all dead files inside tests/ui/

[fmease]

While rebasing #135860 I noticed that there are several dead *.stderr files inside tests/ui/.

When I checked thoroughly, I found 69 dead *.$revision.stderr files, 3 other dead *.stderr files and one dead *.rs file.

Prior to #134808, compiletest's --bless didn't remove dead *.stderr files when the set of revisions changed in any way (renamings, removals, additions, …) which explains their existence.

Regarding the dead *.rs file, that one was located inside an auxiliary/ directory (together with a *.stderr file) despite not being meant to be an auxiliary file (it's not referenced by any //@ aux-*, it has an accompanying *.stderr file and it's obvious from looking at #111056 which added it). Ideally compiletest or tidy would forbid *.std{out,err} files inside auxiliary/ dirs, that would've caught it. I moved it, updated it and turned it into a proper UI test.

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How to reproduce:

1. Run rm tests/ui/**/*.stderr
2. Run ./x test tests/ui --bless (or similar)
3. Manually / semi-automatically go through all tests that were ignored (likely due to your OS etc. not matching) and restore any stderr files that were overzealously removed

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r? compiler

[compiler-errors]

r=me when green

[fmease]

@bors r=compiler-errors

[bors]

📌 Commit c38951b has been approved by compiler-errors

It is now in the queue for this repository.

[lqd]

This seems to remove the polonius compare-mode expectations, which are not theoretically dead files but in practice will be outdated, could be dead, etc since they’re not tested on CI.

Compare modes were not intended to be used like the new solver does with explicit revisions, but by just blessing the expectations and running the compare mode itself on CI. This is lower friction but can create dead files, if the tests aren’t run by default (or when removing stderrs and reblessing) like for polonius or chalk, so the new solver approach works better in that regard.

Given that the chalk compare mode is gone, that we’re migrating away from these old polonius tests because of the new implementation, that reblessing would encounter issues on the tests that are too slow to run (the reason why it’s not enabled on CI), and fixing that would also create more churn when we complete the new implementation diagnostics and run tests on CI, I guess it’s fine to remove them? :)

[fmease]

This seems to remove the polonius compare-mode expectations, which are not theoretically dead files but in practice will be outdated, could be dead, etc since they’re not tested on CI.

Oof I totally missed that, sorry about that! I'm glad you're somewhat okay with this PR. From what I've gathered from your comment, those *.polonius.stderr files are basically dead weight in practice as running ./x t tests/ui --compare-mode=polonius before my PR would've likely lead to failures, too, especially as time goes on. Whereas now, you have to pass --bless when running the compare mode.