How to clean up data store after each test in unit tests? Using ``` @After fun tearDown() = ...

# android

[Abhimanyu]

How to clean up data store after each test in unit tests?
Using

@After
    fun tearDown() = testScope.runTest {
        testDataStore.edit {
            it.clear()
        }
        testScope.cancel()
    }

Getting error

Only a single call to runTest can be performed during one test.

As both the test method and tearDown() uses runTest

Stackoverflow question - https://stackoverflow.com/questions/77025162/data-store-clean-up-in-unit-test-error-only-a-single-call-to-runtest-can-be

Please help.
Thanks

[solonovamax]

initialize the test scope per-test

[Peter]

I think using runBlocking() is a valid use case for this. From documentation:

It is designed to bridge regular blocking code to libraries that are written in suspending style, to be used in main functions and in tests.

And I think this is probably a valid case, where you need to bridge regular blocking code. JUnit doesn't support suspending.

Alternatively, you could probably also make a helper function, that does cleanup.

@Test
fun someTest() {
    runTestAndCleanup {
        // test code
    }
}

private fun runTestAndCleanup(block: suspend () -> Unit) = runTest {
    try {
        block()
    } catch(e) {
        TODO("cleanup")
        throw e
    }
}

[Abhimanyu]

Thanks, the helper function seems like a better idea.
Currently I had the cleanup code in a separate method and I was calling it in all tests. (it can be missed easily in new tests.)