compose-jb/tutorials/UI_Testing

UI Testing

The API for unit testing in Compose for Desktop is nearly identical to the Jetpack Compose Android testing API. We highly recommended reading that first before moving on to this tutorial.

Setting up

To start using the testing API, you will need to add the dependency on compose.uiTestJUnit4 to your build.gradle file and create the directory for your tests.

If the module is desktop-only (kotlin("jvm") is applied), add the dependency via:

dependencies {
    testImplementation(compose.desktop.uiTestJUnit4)
    testImplementation(compose.desktop.currentOs)
}

and the directory for tests will be src/test/kotlin

If the module is multiplatform (kotlin(“multiplatform”) is applied), add it via:

kotlin {
    sourceSets {
        val desktopTest by getting {
            dependencies {
                implementation(compose.desktop.uiTestJUnit4)
                implementation(compose.desktop.currentOs)
            }
        }
    }
}

And the directory for tests will be src/desktopTest/kotlin

Creating your first test

In the tests directory, create a file named ExampleTest.kt and paste this code into it:

import androidx.compose.material.*
import androidx.compose.runtime.*
import androidx.compose.ui.Modifier
import androidx.compose.ui.test.*
import androidx.compose.ui.platform.testTag
import androidx.compose.ui.test.junit4.createComposeRule
import org.junit.Rule
import org.junit.Test

class ExampleTest {
    @get:Rule
    val rule = createComposeRule()

    @Test
    fun myTest(){
        rule.setContent {
            var text by remember { mutableStateOf("Hello") }
            Text(
                text = text,
                modifier = Modifier.testTag("text")
            )
            Button(
                onClick = { text = "Compose" },
                modifier = Modifier.testTag("button")
            ){
                Text("Click me")
            }
        }

        rule.onNodeWithTag("text").assertTextEquals("Hello")
        rule.onNodeWithTag("button").performClick()
        rule.onNodeWithTag("text").assertTextEquals("Compose")
    }
}

Now you can run the test by either clicking button in your IDE, or from the command line with

./gradlew test