Add runComposeUiTest API snippets

compose/snippets/src/androidTest/java/com/example/compose/snippets/test/TestSnippets.kt

@@ -0,0 +1,86 @@
+/*
+ * 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
+ *
+ *     https://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 com.example.compose.snippets.test
+
+import androidx.compose.material3.Text
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.test.ExperimentalTestApi
+import androidx.compose.ui.test.assertIsDisplayed
+import androidx.compose.ui.test.junit4.v2.createComposeRule
+import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.v2.runComposeUiTest
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.test.advanceTimeBy
+import kotlinx.coroutines.test.runTest
+import org.junit.Rule
+import org.junit.Test
+
+class RunComposeUiTest {
+
+    @OptIn(ExperimentalTestApi::class)
+// [START android_compose_test_runComposeUiTest]
+    @Test
+    fun testWithCoroutines() = runComposeUiTest {
+        setContent {
+            var status by remember { mutableStateOf("Loading...") }
+            LaunchedEffect(Unit) {
+                delay(1000)
+                status = "Done!"
+            }
+            Text(text = status)
+        }
+
+        onNodeWithText("Loading...").assertIsDisplayed()
+        mainClock.advanceTimeBy(1000 + 16 /* Frame buffer */)
+        onNodeWithText("Done!").assertIsDisplayed()
+    }
+}
+// [END android_compose_test_runComposeUiTest]
+
+class Test2 {
+// [START android_compose_test_v2_apis]
+    @get:Rule
+    val composeTestRule = createComposeRule()
+
+    @Test
+    fun testWithCoroutines() {
+        composeTestRule.setContent {
+            var status by remember { mutableStateOf("Loading...") }
+            LaunchedEffect(Unit) {
+                delay(1000)
+                status = "Done!"
+            }
+            Text(text = status)
+        }
+
+        // NOT RECOMMENDED
+        // Fails: runTest creates a new, separate scheduler.
+        // Advancing time here does NOT advance the compose clock.
+        // To fix this without migrating, you would need to share the scheduler
+        // by passing 'composeTestRule.mainClock.scheduler' to runTest.
+        runTest {
+            composeTestRule.onNodeWithText("Loading...").assertIsDisplayed()
+            advanceTimeBy(1000)
+            composeTestRule.onNodeWithText("Done!").assertIsDisplayed()
+        }
+    }
+// [END android_compose_test_v2_apis]
+}