fix(jest-circus) correct concurrent event ordering

[madcapnmckay]

Summary

Note this is a re-raise of an old PR that I previously let go stale.

I'm unsure if this is a major, minor, or patch change. It does not change the API, but it changes the order of events emitted from jest-circus. Please advise.

This fixes the issue documented here

When using test.concurrent events such as test_start, test_started, and test_fn_start are dispatched after the body of the test is executed. This is due to the _runTest function not being executed as part of the parallel execution runner; instead, it was executed synchronously like non-concurrent tests.

The solution was to use _runTest within startTestsConcurrently() and then wait for that process to complete instead of replacing the test.fn as was being done before.

I also added a bunch of e2e tests for concurrent, this change most likely closes some other issues relating to before/afterAll.

Test plan

• Checkout commit 953bbed700
• Run yarn test packages/jest-circus/src/__tests__/baseTest.test.ts to observe the broken snapshot content for the concurrent test.

hello one <-- test running before `test_start` has fired.
hello two
hello three
run_describe_start: describe
test_start: one
test_started: one
test_fn_start: one
test_fn_failure: one

• Check out HEAD and rerun the test. Note that the output has been reordered to match the expectation that the circus actions occur before and after the test execution.
• Execute the new concurrent e2e tests with yarn jest e2e/__tests__/circusConcurrent.test.ts and yarn jest e2e/__tests__/testRetries.test.ts

Note: at the time this is being raised main does not pass yarn test, I have confirmed that the same tests are failing before and after my change.

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[madcapnmckay]

@SimenB - the failures on the checks seem to be affecting other PRs.

[SimenB]

Hey, sorry about the radio silence! CI should be fixed now, and I've merged in main here.

[SimenB]

I think this makes sense, looking at the implementation changes. And the extensive tests (thank you!!!) also seems reasonable to me

[SimenB]

https://github.com/jestjs/jest/releases/tag/v30.0.0-alpha.7