Add snippets for https://developer.android.com/jetpack/compose/semantics (#36)

Author: JolandaVerhoef

compose/snippets/src/androidTest/java/com/example/compose/snippets/semantics/SemanticsSnippets.kt

@@ -0,0 +1,92 @@
+/*
+ * Copyright 2023 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.semantics
+
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.semantics.Role
+import androidx.compose.ui.semantics.SemanticsProperties
+import androidx.compose.ui.test.SemanticsMatcher
+import androidx.compose.ui.test.assertIsOff
+import androidx.compose.ui.test.junit4.createComposeRule
+import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.onRoot
+import androidx.compose.ui.test.performClick
+import androidx.compose.ui.test.printToLog
+import org.junit.Rule
+import org.junit.Test
+
+@Suppress("TestFunctionName")
+// [START android_compose_semantics_logging]
+class MyComposeTest {
+
+    @get:Rule
+    val composeTestRule = createComposeRule()
+
+    @Test
+    fun MyTest() {
+        // Start the app
+        composeTestRule.setContent {
+            MyTheme {
+                Text("Hello world!")
+            }
+        }
+        // Log the full semantics tree
+        composeTestRule.onRoot().printToLog("MY TAG")
+    }
+}
+// [END android_compose_semantics_logging]
+
+class Test2 {
+    @get:Rule
+    val composeTestRule = createComposeRule()
+
+    @Test
+    fun testSwitch() {
+        // [START android_compose_semantics_test_switch]
+        val mySwitch = SemanticsMatcher.expectValue(
+            SemanticsProperties.Role, Role.Switch
+        )
+        composeTestRule.onNode(mySwitch)
+            .performClick()
+            .assertIsOff()
+        // [END android_compose_semantics_test_switch]
+    }
+}
+
+class Test3 {
+    @get:Rule
+    val composeTestRule = createComposeRule()
+
+    @Test
+    fun testLog() {
+        // [START android_compose_semantics_print_log]
+        composeTestRule.onRoot(useUnmergedTree = true).printToLog("MY TAG")
+        // [END android_compose_semantics_print_log]
+        // [START android_compose_semantics_match_text]
+        composeTestRule.onNodeWithText("Like").performClick()
+        // [END android_compose_semantics_match_text]
+    }
+}
+
+@Suppress("TestFunctionName")
+@Composable
+private fun MyTheme(
+    content: @Composable () -> Unit
+) {
+    content()
+}

compose/snippets/src/main/java/com/example/compose/snippets/semantics/SemanticsSnippets.kt

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2023 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.
+ */
+
+@file:Suppress("unused")
+
+package com.example.compose.snippets.semantics
+
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.size
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Favorite
+import androidx.compose.material3.Button
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.Icon
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.tooling.preview.Preview
+
+@Preview
+@Composable
+private fun Merging() {
+    // [START android_compose_semantics_merging]
+    Button(onClick = { /*TODO*/ }) {
+        Icon(
+            imageVector = Icons.Filled.Favorite,
+            contentDescription = null
+        )
+        Spacer(Modifier.size(ButtonDefaults.IconSpacing))
+        Text("Like")
+    }
+    // [END android_compose_semantics_merging]
+}