Move unit tests to a 'unit tests' stage

Related, 📌 [PP-1][CI] Spin off Drupal Components tests in a job of their own Postponed .

We are talking about a job stage, not a child pipeline here, right?

Yeah just a job stage. Also we should explicitly postpone this issue on that one.

Thanks for opening this, I was the one who suggested this in Slack. I had a bit of a tinker but I couldn't figure out the relationship between the child pipeline and the initial stage(s). Will be following this issue.

Somehow though, this will reopen the discussion from #3484966-6: Allow executing unit tests on multiple PHP images without having to duplicate unit tests across all environment combinations → because then the tests results will be split in two places - the 'main' pipeline for unit tests and the children pipelines for kernel/functional/etc.

https://gitlab.com/gitlab-org/gitlab/-/issues/363019 is the upstream issue to keep watching - still no timeline there.

My idea here was a separate stage without a child pipeline.

However I think what @mstrelan is referring to is that the child pipeline depends on the entire parent pipeline, not a stage, so yeah it's (inadvertently) re-opening that discussion because I forgot this is hard to do.

Blocker went in.

Here's another GitLab upstream issue to watch for child/parent pipeline relationship https://gitlab.com/groups/gitlab-org/-/epics/4019, looks like it's actively pursued.

After last mess with parent child access in Gitlab I find it bad idea to bet on getting artifacts/results from child pipeline

Agree with Andy. Might even advocate stop using child pipelines all together.

The MR is now splitting the unit tests in a stage of its own - still the new stage's jobs are set to start without waiting for the 'Lint' stage to end.

Not sure why we would remove "Unit tests" from the title here, i understand it's now in a "Unit test" stage. But lets consider;

- Running locally would mean running "Core on PHP 8.3"
- If tests fail "Core on PHP 8.3" is the title of the job.
- All other jobs are things like "PHPUnit Functional"

I'd probably opt to call them something like:

"Core Unit tests on PHP 8.3"
"Component Unit tests on PHP 8.3"

Or maybe:
"PHPUnit Unit Core (PHP 8.3)"
"PHPUnit Unit Components (PHP 8.3)"
"Unit tests: Core (PHP 8.3)"
"Unit tests: Components (PHP 8.3)"

Know this is pretty nitpicky, but we are gonna look at those a lot :)

Let’s have opinions on the best naming from #13 before making changes.

Meanwhile, better wait for 🐛 [CI] Components tests coverage metrics differ by PHP version Active to get in.

For the record. I'd pick:

"Unit tests: Core (PHP 8.3)"
"Unit tests: Components (PHP 8.3)"