I'm trying to write test for a compose component w...

# compose

[Alex C]

I'm trying to write test for a compose component which has a LazyColumn inside
I expect I can assert the count of the items in the LazyColumn, but it seems the children of onChildren() includes some of the sub-hierarchies.
For example,

val testData = listOf("item1", "item2", "item3")
composeTestRule.setContent {
            LazyColumn(Modifier.testTag(TEST_TAG)) {
                itemsIndexed(testData) { index, item ->
                    Row {
                        Text("index $index: ")
                        Spacer(modifier = Modifier.height(10.dp))
                        Text(item)
                    }
                }
            }
        }
composeTestRule.onNodeWithTag(TEST_TAG).onChildren().assertCountEquals(3)

It turns out the actual count of the children is 6 rather than 3, which counts the Text("index $index: ") and Text(item) inside the Row but not the Spacer()
But what I actually want is to count how many rows in the LazyColumn.
So how can I do it?

[Alex C]

I end up adding a testTag in the composable I want to count and filter the tag

[Alex C]

But I'm keen to understand how the nodes being count. like what is considered a 'node' what is not? If I write a Composable fun can I make it counted as a note?

[Alex C]

Found the answer here 🙂https://developer.android.com/jetpack/compose/testing#semantics

[John Nichol]

I see you got to the answer Alex - I find testing the LazyXXXX components by observing the LazyListLayoutInfo is also a useful tool to have in your bag. E.g. https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:wear/com[…]ayoutInfoTest.kt?q=f:test%20f:layoutinfo%20f:wear&ss=androidx