Add t.Parallel() to several tsh tests

[jakule]

Added the t.Parallel() function call in each test function to enable parallel test execution. This should reduce the overall time it takes to run all these tests by enabling them to run concurrently.

[ibeckermayer]

Potentially worth running these in parallel manually like

func TestTest(t *testing.T) {
    for i := 0; i < 10; i++ {
        t.Run(fmt.Sprintf("iteration %d", i), TestTheTestIWantToRepro)
    }
}

to double check that it doesn't cause issues.

[jakule]

Potentially worth running these in parallel manually like

func TestTest(t *testing.T) {
    for i := 0; i < 10; i++ {
        t.Run(fmt.Sprintf("iteration %d", i), TestTheTestIWantToRepro)
    }
}

to double check that it doesn't cause issues.

Is there any difference between this method and go test -count=10?

[public-teleport-github-review-bot]

@jakule See the table below for backport results.

Branch	Result
branch/v13	Create PR

[ibeckermayer]

Potentially worth running these in parallel manually like

func TestTest(t *testing.T) {
    for i := 0; i < 10; i++ {
        t.Run(fmt.Sprintf("iteration %d", i), TestTheTestIWantToRepro)
    }
}

to double check that it doesn't cause issues.

Is there any difference between this method and go test -count=10?

Yes I believe there is. Subtests and Sub-benchmarks ¶ gives the examples:

showing how to cause tests run in parallel with and only with each other. So the example code I gave would have the TestTheTestIWantToRepro running in parallel 10 times (with itself).

OTOH as far as I've been able to tell, -count=10 simply runs the entire test suite 10 times sequentially. So, presuming you're just running a single test rather than the entire suite, a call like

go test -count=10 -run ^TestTheTestIWantToRepro$

won't run anything in parallel, it will just run TestTheTestIWantToRepro 10 times, one after the other.

If you're running the entire test suite then it's a different story, as the test in question will be run parallel to other t.Parallel() tests.