litho-testing/com.facebook.litho.testing/LithoViewRule

LithoViewRule

class LithoViewRule @JvmOverloads constructor(val componentsConfiguration: ComponentsConfiguration? = null, val themeResId: Int? = null, lithoVisibilityEventsController: () -> LithoVisibilityEventsController? = null) : TestRule

This test utility allows clients to create a TestLithoView instance that allows to test assertion on the view hierarchy rendered by a Litho components.

 @RunWith(AndroidJUnit4::class)
 class LithoSampleTest {

 @Rule @JvmField val lithoViewRule = LithoViewRule()
 @Test
 fun test() {
  val testLithoView =  lithoViewRule.render { TestComponent() }

   // or you can use setRoot/measure/layout for more fine-grained control
   val testLithoView = lithoViewRule.createTestLithoView().attachToWindow().setRoot(TestComponent()).measure().layout()
   // Test your assertions on the TestLithoView instance.
   }
}

Constructors

LithoViewRule

@JvmOverloads

constructor(componentsConfiguration: ComponentsConfiguration? = null, themeResId: Int? = null, lithoVisibilityEventsController: () -> LithoVisibilityEventsController? = null)

Properties

componentsConfiguration

val componentsConfiguration: ComponentsConfiguration? = null

context

lateinit var context: ComponentContext

themeResId

val themeResId: Int? = null

Functions

act

fun act(testLithoView: TestLithoView, action: TestLithoView.InteractionsScope.() -> Unit): LithoViewRule

Perform any interactions defined in the InteractionScope or on the LithoViewRule.

apply

open override fun apply(base: Statement, description: Description): Statement

createTestLithoView

@JvmOverloads

fun createTestLithoView(lithoView: LithoView? = null, componentTree: ComponentTree? = null, widthPx: Int? = null, heightPx: Int? = null, componentFunction: ComponentScope.() -> Component?? = null): TestLithoView

Creates new TestLithoView holder responsible for keeping an instance of LithoView, allowing to find Views/Components or perform assertions on it. For simple Component rendering without fine-grained control, use render

idle

fun idle()

Runs through all tasks on the background thread and main lopper, blocking until it completes. Use if there are any async events triggered by layout ( ie visibility events) to manually drain the queue

render

@JvmOverloads

fun render(lithoView: LithoView? = null, componentTree: ComponentTree? = null, widthPx: Int? = null, heightPx: Int? = null, componentFunction: ComponentScope.() -> Component?): TestLithoView

Sets the new root to render.

setTreeProp

fun setTreeProp(klass: Class<*>, instance: Any?): LithoViewRule

Sets a new TreeProp for the next layout pass.

useContext

fun useContext(c: ComponentContext): LithoViewRule

withThrowOnErrorHandler

fun withThrowOnErrorHandler(): ComponentTree

Creates a ComponentTree that will propagate exceptions.