CC @aduh95

/cc @nodejs/test_runner

CI: https://ci.nodejs.org/job/node-test-pull-request/45274/

Hum it looks like it makes message/test_runner_desctibe_it flaky. @MoLow do you know where this might be coming from?

=== release test_runner_desctibe_it.js ===
Path: message/test_runner_desctibe_it.js
Error: --- stderr ---
node:internal/test_runner/harness:29
      throw err;
      ^
TypeError: Cannot mix BigInt and other types, use explicit conversions
    at ItTest.report (node:internal/test_runner/test:425:42)
    at ItTest.finalize (node:internal/test_runner/test:418:10)
    at Test.processReadySubtestRange (node:internal/test_runner/test:195:15)
    at ItTest.postRun (node:internal/test_runner/test:388:19)
    at Test.postRun (node:internal/test_runner/test:370:17)
    at process.exitHandler (node:internal/test_runner/harness:79:10)
    at process.emit (node:events:513:28)
Node.js v19.0.0-pre

Hum it looks like it makes message/test_runner_desctibe_it flaky. @MoLow do you know where this might be coming from?

@aduh95
yes, it happens when a test is canceled and was not yet assigned a start time. you can see I already fixed that here
adding concurrency introduced a timing condition that made it more likely to happen since previously when a suite ran serially - either a child test did not run or it did, it was never queued.

I suggest waiting for the fix to land, then rebase and make sure test is stable in this branch

CI: https://ci.nodejs.org/job/node-test-pull-request/45347/

CI: https://ci.nodejs.org/job/node-test-pull-request/45355/

CI: https://ci.nodejs.org/job/node-test-pull-request/45365/

I'm surprised by this, is it actually expected to run it tests in parallel?

I don't think it is - jest runs files in parallel (as does mocha, i believe), but i'm not aware of anything that runs individual its in parallel.

perhaps this should be a feature that is off by default?

Since this PR conflicts main and needs to be updated anyway - I will add the conclusion gathered in this discussion and re-request code reviews

so the current implementation in this PR works this way:

• in the level of a test/it the default concurrency is 1
• when running --test, the default will be the number of CPUs, see:

• I want to leave support for boolean value for the concurrency setting out of the scope of this PR since the number of CPUs as a default only makes sense to me at the file level since each file spawns its own process. inside a file this isn't necessarily a good default - I will open a separate issue to discuss this

CI: https://ci.nodejs.org/job/node-test-pull-request/45448/

so the current implementation in this PR works this way:

• in the level of a test/it the default concurrency is 1

The code still looks like it runs all tests in parallel with unlimited concurrency, also the testTimeout has been removed

The code still looks like it runs all tests in parallel with unlimited concurrency, also the testTimeout has been removed

the default is currently 1, see #43757 (comment)

also the testTimeout has been removed

I am not sure if timeout is needed in describe and if it should support an asynchronous function, anyway - I will sort that out in #43554

Landed in a3766bc