Implement SkikoComposeUiTest.runWithoutImplicitWait (#3168)

Author: m-sasha

compose/ui/ui-test/src/skikoMain/kotlin/androidx/compose/ui/test/ComposeUiTest.skiko.kt

@@ -453,8 +453,7 @@ open class SkikoComposeUiTest @InternalTestApi constructor(
     }
 
     override fun <T> runWithoutImplicitWait(block: () -> T): T {
-        // TODO https://youtrack.jetbrains.com/issue/CMP-10244/ui-test.-Implement-runWithoutImplicitWait
-        throw NotImplementedError("runWithoutImplicitWait is not implemented.")
+        return testOwner.withImplicitWaitSuppression(isSuppressed = true, block = block)
     }
 
     override fun waitUntil(
@@ -534,6 +533,21 @@ open class SkikoComposeUiTest @InternalTestApi constructor(
         return captureToImage(fetchSemanticsNode())
     }
 
+    /** Executes the given [block] while temporarily setting the implicit wait suppression state. */
+    private inline fun <T> TestOwner.withImplicitWaitSuppression(
+        isSuppressed: Boolean,
+        block: () -> T,
+    ): T {
+        val previousState = this.isImplicitWaitSuppressed
+        this.isImplicitWaitSuppressed = isSuppressed
+        return try {
+            block()
+        } finally {
+            // Always restore the original synchronization state
+            this.isImplicitWaitSuppressed = previousState
+        }
+    }
+
     @OptIn(InternalComposeUiApi::class)
     internal inner class SkikoTestOwner : TestOwner {
         override var isImplicitWaitSuppressed: Boolean = false

compose/ui/ui-test/src/skikoTest/kotlin/androidx/compose/ui/test/RunWithoutImplicitWaitTest.kt

@@ -0,0 +1,138 @@
+/*
+ * Copyright 2026 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package androidx.compose.ui.test
+
+import androidx.compose.animation.animateContentSize
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.size
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.platform.testTag
+import androidx.compose.ui.test.v2.runComposeUiTest
+import androidx.compose.ui.unit.Density
+import androidx.compose.ui.unit.IntSize
+import androidx.compose.ui.unit.dp
+import androidx.kruth.assertThat
+import kotlin.test.Test
+
+// Copied from androidDeviceTest
+class RunWithoutImplicitWaitTest {
+    @OptIn(ExperimentalTestApi::class)
+    @Test
+    fun triggeredAnimationAndCaptureMotionValues() = runComposeUiTest {
+        var size by mutableStateOf(64.dp)
+
+        var animationIsDone = false
+        setContent {
+            CompositionLocalProvider(LocalDensity provides Density(1f)) {
+                Box(
+                    modifier =
+                        Modifier.testTag("foo")
+                            .animateContentSize { _, _ -> animationIsDone = true }
+                            .size(size)
+                            .background(Color.Red)
+                )
+            }
+        }
+
+        mainClock.autoAdvance = false
+
+        val timeSeries = mutableListOf<IntSize>()
+        size = 32.dp
+
+        while (!animationIsDone) {
+            mainClock.advanceTimeByFrame()
+            waitForIdle()
+            runOnUiThread { runWithoutImplicitWait { captureMotionTestValues(timeSeries) } }
+        }
+        assertThat(timeSeries)
+            .containsExactly(
+                IntSize(64, 64),
+                IntSize(64, 64),
+                IntSize(63, 63),
+                IntSize(60, 60),
+                IntSize(56, 56),
+                IntSize(52, 52),
+                IntSize(49, 49),
+                IntSize(46, 46),
+                IntSize(43, 43),
+                IntSize(41, 41),
+                IntSize(39, 39),
+                IntSize(37, 37),
+                IntSize(36, 36),
+                IntSize(35, 35),
+                IntSize(35, 35),
+                IntSize(34, 34),
+                IntSize(34, 34),
+                IntSize(33, 33),
+                IntSize(32, 32),
+            )
+            .inOrder()
+    }
+
+    @OptIn(ExperimentalTestApi::class)
+    @Test
+    fun runWithoutImplicitWait_doesNotTriggerWaitForIdle() = runComposeUiTest {
+        var isNodeVisible by mutableStateOf(true)
+
+        setContent {
+            if (isNodeVisible) {
+                Box(modifier = Modifier.testTag("dummy_node"))
+            }
+        }
+
+        isNodeVisible = false
+
+        runOnUiThread {
+            runWithoutImplicitWait {
+                // In a normal context, onNodeWithTag() forces a waitForIdle(),
+                // which would execute the pending recomposition.
+                onNodeWithTag("dummy_node")
+                    .assertExists(
+                        "waitForIdle() was called internally, breaking the suppression contract!"
+                    )
+            }
+        }
+        // Calling onNodeWithTag outside runWithoutImplicitWait will now force idle.
+        // This executes the pending recomposition, removing the node, and hence it won't exist
+        // anymore.
+        onNodeWithTag("dummy_node").assertDoesNotExist()
+    }
+
+    /**
+     * Illustrative implementation of a "sample the property values of the current frame" method.
+     *
+     * Motion tests do exactly that, just with more syntactic sugar 🍬.
+     */
+    @OptIn(ExperimentalTestApi::class)
+    private fun ComposeUiTest.captureMotionTestValues(fooSizeTimeSeries: MutableList<IntSize>) {
+        // Capture a value and add to the time series.
+        fooSizeTimeSeries.add(onNodeWithTag("foo").fetchSemanticsNode().size)
+
+        repeat(100) {
+            // simulation of capturing multiple properties.
+            // For making the point, this just repeatedly captures the same property.
+            onNodeWithTag("foo").fetchSemanticsNode().size
+        }
+    }
+}