IssueTracker

please don't assertExsists in onNodeXXX but return null on failure, to allow something like that:

val node = onNode(hasTag(...)) ?: onNode(hasText(...))

Note, not all missing items are necessarily a test failure.
We have assertExists, if we want to test this.
If onNode would return null, it can be used for both cases, but the current variant cannot do both.

Alternatively you could add another implementation, something like onNodeOptional.

waitUntil (or a variant of it) should return the value from the block.
Currently there is no way to detect if the timeout expired.
It's more usable if the value could be anything or null.

val node = waitUntil { if... return node else null }

You will say, this is offtopic here, but the functions above should have similar behavior.

that's the code I use currently:

fun ComposeContentTestRule.onNodeWait(
    matcher: SemanticsMatcher,
    timeoutMillis: Long = 1_000L
): SemanticsNodeInteraction? {
    var node: SemanticsNodeInteraction? = null
    try {
        this.waitUntil(timeoutMillis) {
            val nodes = this.onAllNodes(matcher)
            if(nodes.fetchSemanticsNodes().size > 0) {
                node = nodes.onFirst()
                true
            } else
                false
        }
    } catch(e: ComposeTimeoutException) {
        Timber.d("----------", "Timeout onNodeWait($matcher, $timeoutMillis)")
        return null
    }
    return node
}

fun ComposeContentTestRule.onNodeWaitOrAssert(
    matcher: SemanticsMatcher,
    timeoutMillis: Long = 1_000L,
    assert: Boolean = false
): SemanticsNodeInteraction {
    val node = onNodeWait(matcher, timeoutMillis)
    return node ?: throw AssertionError("node with (${matcher.description}) does not exist")
}


it is used like this:


val column = test.onNodeWait(hasTestTag("VerticalItemList.Column"), 10000)
column?.printToLog("column") ?: Timber.d("----------", "ERROR: <show some data to see why it is missing>")
// it would be possible to do some alternative here if we didn't get the node,
// maybe there is a question to be answered, before the list is created
assert(column != null)
column?.let {
    [...]
    // open menu again
    it.onChildAt(0).performTouchInput { longClick(center) }
    test.waitForIdle()
    it.onChildAt(0).performTouchInput { longClick(center) }
    test.waitForIdle()
    // open sub-menu "Load"
    test.onNodeWaitOrAssert(hasText("Load")).performTouchInput { click(center) }
    test.waitForIdle()
    // count menu items
    val count = test.onAllNodesWithText(selectionName).fetchSemanticsNodes().size
    assertEquals("menu entries", count, 1)

Project: platform/frameworks/support
Branch: androidx-main

commit 2118900c6c4b44749cb6ac30bfb71d8b13fbc665
Author: Izer Onadim <izeronadim@google.com>
Date:   Mon Jun 27 12:55:50 2022

    Improve rule.waitUntil API to accept a matcher
   
    Extend the `ComposeTestRule.waitUntil` API to accept a matcher and
    any count of nodes by adding experimental `waitUntilNodeCount`. Add
    some syntactic sugar with `waitUntilAtLeastOneExists`,
    `waitUntilExactlyOneExists` and `waitUntilDoesNotExist`.
   
    Bug: 226934294
    Test: ./gradlew compose:ui:ui-test-junit4:test
          && ./gradlew compose:ui:ui-test-junit4:cC
    Relnote: "Added `waitUntilNodeCount`, `waitUntilAtLeastOneExists`,
    `waitUntilExactlyOneExists` and `waitUntilDoesNotExist` as
    experimental API to `ComposeTestRule`, extending the `waitUntil` API
    to accept any matcher and any count of nodes. See `ComposeTestRule`
    for further documentation."
   
    Change-Id: Ifa1b98cf869a78b79f082c4ed8df6c9abd302a87

M       compose/ui/ui-test-junit4/api/public_plus_experimental_current.txt
A       compose/ui/ui-test-junit4/src/androidAndroidTest/kotlin/androidx/compose/ui/test/junit4/ComposeTestRuleWaitUntilTest.kt
A       compose/ui/ui-test-junit4/src/androidAndroidTest/kotlin/androidx/compose/ui/test/junit4/WaitUntilNodeCountTest.kt
M       compose/ui/ui-test-junit4/src/androidMain/kotlin/androidx/compose/ui/test/junit4/AndroidComposeTestRule.android.kt
M       compose/ui/ui-test-junit4/src/commonMain/kotlin/androidx/compose/ui/test/ComposeUiTest.kt
M       compose/ui/ui-test-junit4/src/desktopMain/kotlin/androidx/compose/ui/test/junit4/DesktopComposeTestRule.desktop.kt
M       compose/ui/ui-test-junit4/src/jvmMain/kotlin/androidx/compose/ui/test/junit4/ComposeTestRule.jvm.kt

https://android-review.googlesource.com/2136682