Can we test the component and trigger navigation in "commonTest" which run on test worker (not the Main thread)

[duongphuhiep]

In this test, I didn't execute any navigation yet, but already see error in the log. Although the test still passed -> was it just a warning?

@Test
fun uselessComponentCreationTest() {
    val testComponentContext = TestComponentContext()
    val component =  UselessComponent(testComponentContext)
    assertNotNull(component.childStack)
}

class UselessComponent(
    private val componentContext: ComponentContext,
): ComponentContext by componentContext {

    private val navigation = StackNavigation<Configuration>()
    
    /*
See ERROR on this line when creating the childStack: 
com.arkivanov.decompose.mainthread.NotOnMainThreadException: 
Expected to be called on the main thread, but was Test worker   
  */
    val childStack: Value<ChildStack<*, Child>> = childStack(
        source = navigation,
        serializer = Configuration.serializer(),
        //this is the Startup screen
        initialConfiguration = Configuration.WelcomeScreen,
        handleBackButton = true,
        childFactory = { config, context -> Child.WelcomeScreen }
    )

    @Serializable
    private sealed interface Configuration {
        @Serializable
        data object WelcomeScreen : Configuration
    }

    sealed interface Child {
        data object WelcomeScreen : Child
    }
}

[arkivanov]

The error you presented is just a message in the logs. You can ignore it, or disable the check via onDecomposeError = null.

I think this should only be happening in JVM tests if you also have dependency on extensions-compose or extensions-compose-experimental module. I will think if it's possible to disable the check in tests.

[duongphuhiep]

thanks, I run tests on JVM, and yes, it is cleaner to bypass this check in test if possible

[ahparhizgar]

I noticed that currently there is a filed named mainThreadCheckEnabled inside DecomposeSettings that we can set in our tests.

[arkivanov]

Correct. The new API has been added (#490) in version 3.5.0.