testing-lazy-lists

To test off-screen items in a Jetpack Compose LazyColumn, use semantic scroll primitives like performScrollToIndex to bring the item into the viewport, then verify its visibility using assertIsDisplayed.

assertExists fails for items in a Compose lazy list because it checks the semantic tree rather than the rendered viewport; you must use assertIsDisplayed to confirm the lazy layout item is actually visible on screen.

You can verify scroll state and item placement in Compose UI testing by probing state.layoutInfo, which provides deterministic data about the current list state and the positioning of items within the lazy layout.

The best way to handle animations when testing LazyVerticalGrid is to use deterministic clock management, ensuring that item placement animations and layout state verification occur predictably during the test.

Yes, you need stable test tags for semantic scrolling in Jetpack Compose, because standardized semantic scroll primitives and visibility verification rely on consistent tagging to locate items in LazyColumn and LazyRow components.