How can I get string resource in Jetpack composable test

Question

We can get the string resource in Composable through stringResource like

@Composable
fun Heading(
    @StringRes textResource: Int
) {
    Text(
        text = stringResource(id = textResource),
        color = colorBlack,
    )
}

But how can we get this string resource in composable test.

class HeadingTest {

    @get:Rule
    val composeTestRule = createComposeRule()

    @ExperimentalComposeUiApi
    @Test
    fun headingTest() {
        // Start the app
        composeTestRule.setContent {
            AppTheme {
                // In Compose world
                Heading(textResource = R.string.some_text)
            }
        }

        //How can I access string resource here
        composeTestRule.onNodeWithText(???).assertExists()
    }
}

Answer 1

Create compose rule via createAndroidComposeRule and then you will be able to access activity.getString() method

@get:Rule
val composeTestRule = createAndroidComposeRule<MainActivity>()

val activity = composeTestRule.activity

@Test
fun testDisplayAndClickable() {
    val home = composeTestRule.activity.getString(R.string.home)
}

Answer 2

I'm not sure if there's a better way, but you can do the following:

class HeadingTest {

    @get:Rule
    val composeTestRule = createComposeRule()

    @ExperimentalComposeUiApi
    @Test
    fun headingTest() {
        val textId = R.string.some_text
        var string = ""
        // Start the app
        composeTestRule.setContent {
            string = stringResource(id = textId)
            AppTheme {
                // In Compose world
                Heading(textResource = textId)
            }
        }
        composeTestRule.onNodeWithText(string).assertExists()
    }
}

Answer 3

You can get an activity instance if you initiate AndroidComposeTestRule

class HeadingTest {

    @get:Rule
    val androidComposeTestRule = createAndroidComposeRule<ComponentActivity>()


    @ExperimentalComposeUiApi
    @Test
    fun headingTest() {
        // Start the app
        androidComposeTestRule.setContent {
            AppTheme {
                // In Compose world
                Heading(textResource = R.string.some_text)
            }
        }

        //Call getString() from activity instance
        androidComposeTestRule.onNodeWithText(androidComposeTestRule.activity.getString(R.string.some_text))
            .assertExists()
    }
}

Answer 4

Still you can use androidx.test.platform.app.InstrumentationRegistry to get resource in composeapp.

    val context: Context = InstrumentationRegistry.getInstrumentation().getTargetContext()
    var string2 = context.resources.getString(R.string.hello_world)