Add childCountScreenshotTest: screenshot after waiting for children to mount#114
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EmilioBejasa wants to merge 6 commits into
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Add childCountScreenshotTest: screenshot after waiting for children to mount#114EmilioBejasa wants to merge 6 commits into
EmilioBejasa wants to merge 6 commits into
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…ith view.post check - Remove ViewHelpers from constructViewTest and childCountTest (IsolatedTest.kt) and testSimpleTextView (ScreenshotTest.kt); use explicit measure()/layout() calls - Replace 30s poll loop in childCountTest with a self-rescheduling Runnable posted via view.post(), driven by the main-thread Handler that WindowAttachment.dispatchAttach installs in AttachInfo; block test thread on CompletableFuture.get(5s) - Remove childCountScreenshotTest (duplicate of childCountTest + screenshot) - assertGoodTask now captures and awaits startTask so the bg executor is drained before the future is polled Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
…o mount Uses the same view.post polling mechanism as childCountTest to wait for Fabric to mount children before snapping the screenshot, ensuring the result is never blank. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
tdrhq
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Apr 13, 2026
| val view = surface.view!! as ViewGroup | ||
| var detacher: WindowAttachment.Detacher? = null | ||
| var startTask: TaskInterface<Void>? = null | ||
| val childrenMounted = CompletableFuture<Unit>() |
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this is still using concurrency to coordinate between the threads.
| val check = object : Runnable { | ||
| override fun run() { | ||
| if (view.childCount > 0) childrenMounted.complete(Unit) | ||
| else view.postDelayed(this, 50) |
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this is just a different way of writing the previous loop
The previous version duplicated childCountTest's CompletableFuture coordination and view.postDelayed polling. Use prerender()+start() directly, matching the pattern of constructViewTest. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
One runOnMainSync for all setup + start(). waitUntil polls until children are mounted (exits immediately on success, 5s timeout), replacing the CompletableFuture + postDelayed loop from childCountTest. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Use dispatchAttach + onHostResume + waitUntil so Fabric mounts children before the screenshot is taken. Previously the screenshot was blank. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Summary
Stacked on #113.
Adds
childCountScreenshotTesttoIsolatedTest: the sameview.postpolling mechanism fromchildCountTestis used to wait for Fabric to mount children before callingScreenshot.snap(). This guarantees the screenshot is never blank.The screenshot is taken on the test thread (not inside
runOnMainSync) so the JUnit runner context is intact and the file is named correctly.Recorded result: renders "Hello" as expected.
Test plan
childCountScreenshotTestpassesrecordDebugAndroidTestScreenshotTestproduces a non-blank screenshot namedcom.rnstorybookautoscreenshots.IsolatedTest_childCountScreenshotTestverifyDebugAndroidTestScreenshotTestpasses🤖 Generated with Claude Code