put the list of tests run in CI behind a `::group`

[jyn514]

right now, scrolling through a CI log to find a failed test takes quite a while. it would be nice to hide all the successful tests by default so that the failed tests show up right away. we do something similar already for compiling.

this may be kinda tricky because compiletest needs to print this after all the tests have run, but before libtest prints the test report. there might be a hook for this and there might not.

@rustbot label A-contributor-roadblock A-testsuite

[ranger-ross]

I'd like to take a shot at implementing this if no one else is already working on it.

@rustbot claim

[matthiaskrgr]

right now, scrolling through a CI log to find a failed test takes quite a while

do you have an example?
When I click on / curl the plain logs, most of the time the failing tests are directly at the bottom. 🤔

[jieyouxu]

@matthiaskrgr the plain-text log IME loads quite fast and the jump-to-bottom usually works. However the plain-text log has a bunch of unrendered color codes which makes it very annoying to look at, so sometimes you look at the (web) interface. The web interface can be hard to scroll down because it doesn't load all at once...

[matthiaskrgr]

When I curl the plaintext into a terminal, I actually get the fully colored logs displayed as stdout, as the color control chars are dumped straight into the terminal which then renders as it always would.
This makes it much easier to find some errors than it would when looking through a black and white plaintext imo.

The web interface is broken as often I can't even scroll down far enough to see the error 😆

[ranger-ross]

Not directly related to the tests but I noticed that the Docker cache hash key input (pre-hashed) is getting dumped here

rust/src/ci/docker/run.sh

Line 80 in c156614

cat $hash_key

This ends up taking up a pretty good chunk of the non-collapsed logs.

Few examples pulled at random from the Actions tab

• https://github.com/rust-lang/rust/actions/runs/12532244345/job/34950779360
• https://github.com/rust-lang/rust/actions/runs/12209047516/job/34063243601?pr=133995

I think we could probably add a ::group around this, or simply remove this log completely since the actual hash is printed just a few lines later