add ability to match child semantics data (#22001)

examples/flutter_gallery/test/demo/material/chip_demo_test.dart

@@ -14,7 +14,7 @@ void main() {
       home: ChipDemo(),
     ));
 
-    expect(tester.getSemanticsData(find.byIcon(Icons.vignette)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byIcon(Icons.vignette)), matchesSemantics(
       isButton: true,
       hasEnabledState: true,
       isEnabled: true,
@@ -22,7 +22,7 @@ void main() {
       label: 'Update border shape',
     ));
 
-    expect(tester.getSemanticsData(find.byIcon(Icons.refresh)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byIcon(Icons.refresh)), matchesSemantics(
       isButton: true,
       hasEnabledState: true,
       isEnabled: true,

packages/flutter/test/cupertino/slider_test.dart

@@ -330,7 +330,7 @@ void main() {
       ),
     ));
 
-    expect(tester.getSemanticsData(find.byType(CupertinoSlider)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(CupertinoSlider)), matchesSemantics(
       hasIncreaseAction: true,
       hasDecreaseAction: true,
       value: '50%',
@@ -348,7 +348,7 @@ void main() {
       ),
     ));
 
-    expect(tester.getSemanticsData(find.byType(CupertinoSlider)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(CupertinoSlider)), matchesSemantics(
       hasIncreaseAction: true,
       hasDecreaseAction: true,
       value: '60%',

packages/flutter/test/material/back_button_test.dart

@@ -82,7 +82,7 @@ void main() {
 
     await tester.pumpAndSettle();
 
-    expect(tester.getSemanticsData(find.byType(BackButton)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(BackButton)), matchesSemantics(
       label: 'Back',
       isButton: true,
       hasEnabledState: true,

packages/flutter/test/material/checkbox_test.dart

@@ -66,7 +66,7 @@ void main() {
       ),
     ));
 
-    expect(tester.getSemanticsData(find.byType(Checkbox)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(Checkbox)), matchesSemantics(
       hasCheckedState: true,
       hasEnabledState: true,
       isEnabled: true,
@@ -80,7 +80,7 @@ void main() {
       ),
     ));
 
-    expect(tester.getSemanticsData(find.byType(Checkbox)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(Checkbox)), matchesSemantics(
       hasCheckedState: true,
       hasEnabledState: true,
       isChecked: true,
@@ -95,7 +95,7 @@ void main() {
       ),
     ));
 
-    expect(tester.getSemanticsData(find.byType(Checkbox)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(Checkbox)), matchesSemantics(
       hasCheckedState: true,
       hasEnabledState: true,
     ));
@@ -107,7 +107,7 @@ void main() {
       ),
     ));
 
-    expect(tester.getSemanticsData(find.byType(Checkbox)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(Checkbox)), matchesSemantics(
       hasCheckedState: true,
       hasEnabledState: true,
       isChecked: true,
@@ -129,7 +129,7 @@ void main() {
       ),
     ));
 
-    expect(tester.getSemanticsData(find.byType(Checkbox)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(Checkbox)), matchesSemantics(
       label: 'foo',
       textDirection: TextDirection.ltr,
       hasCheckedState: true,

packages/flutter/test/material/dropdown_test.dart

@@ -692,7 +692,7 @@ void main() {
     ));
 
     // By default the hint contributes the label.
-    expect(tester.getSemanticsData(find.byKey(key)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byKey(key)), matchesSemantics(
       isButton: true,
       label: 'test',
       hasTapAction: true,
@@ -707,7 +707,7 @@ void main() {
     ));
 
     // Displays label of select item and is no longer tappable.
-    expect(tester.getSemanticsData(find.byKey(key)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byKey(key)), matchesSemantics(
       isButton: true,
       label: 'three',
       hasTapAction: true,

packages/flutter/test/material/expand_icon_test.dart

@@ -95,7 +95,7 @@ void main() {
         )
     ));
 
-    expect(tester.getSemanticsData(find.byType(ExpandIcon)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(ExpandIcon)), matchesSemantics(
       hasTapAction: true,
       hasEnabledState: true,
       isEnabled: true,
@@ -110,7 +110,7 @@ void main() {
       )
     ));
 
-    expect(tester.getSemanticsData(find.byType(ExpandIcon)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(ExpandIcon)), matchesSemantics(
       hasTapAction: true,
       hasEnabledState: true,
       isEnabled: true,

packages/flutter/test/material/expansion_panel_test.dart

@@ -382,7 +382,7 @@ void main() {
       ),
     );
 
-    expect(tester.getSemanticsData(find.byKey(expandedKey)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byKey(expandedKey)), matchesSemantics(
       label: 'Expanded',
       isButton: true,
       hasEnabledState: true,
@@ -391,7 +391,7 @@ void main() {
       onTapHint: localizations.expandedIconTapHint,
     ));
 
-    expect(tester.getSemanticsData(find.byKey(collapsedKey)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byKey(collapsedKey)), matchesSemantics(
       label: 'Collapsed',
       isButton: true,
       hasEnabledState: true,

packages/flutter/test/material/reorderable_list_test.dart

@@ -462,10 +462,10 @@ void main() {
           ));
 
           // Get the switch tile's semantics:
-          final SemanticsData semanticsData = tester.getSemanticsData(find.byKey(const Key('Switch tile')));
+          final SemanticsNode semanticsNode = tester.getSemantics(find.byKey(const Key('Switch tile')));
 
           // Check for properties of both SwitchTile semantics and the ReorderableListView custom semantics actions.
-          expect(semanticsData, matchesSemanticsData(
+          expect(semanticsNode, matchesSemantics(
             hasToggledState: true,
             isToggled: true,
             isEnabled: true,

packages/flutter/test/material/snack_bar_test.dart

@@ -555,7 +555,7 @@ void main() {
     await tester.tap(find.text('X'));
     await tester.pumpAndSettle();
 
-    expect(tester.getSemanticsData(find.text('snack')), matchesSemanticsData(
+    expect(tester.getSemantics(find.text('snack')), matchesSemantics(
       isLiveRegion: true,
       hasDismissAction: true,
       hasScrollDownAction: true,

packages/flutter/test/material/user_accounts_drawer_header_test.dart

@@ -378,17 +378,17 @@ void main() {
     final SemanticsHandle handle = tester.ensureSemantics();
     await pumpTestWidget(tester);
 
-    expect(tester.getSemanticsData(find.text('B')), matchesSemanticsData(
+    expect(tester.getSemantics(find.text('B')), matchesSemantics(
       label: 'B',
       size: const Size(48.0, 48.0),
     ));
 
-    expect(tester.getSemanticsData(find.text('C')), matchesSemanticsData(
+    expect(tester.getSemantics(find.text('C')), matchesSemantics(
       label: 'C',
       size: const Size(48.0, 48.0),
     ));
 
-    expect(tester.getSemanticsData(find.text('D')), matchesSemanticsData(
+    expect(tester.getSemantics(find.text('D')), matchesSemantics(
       label: 'D',
       size: const Size(48.0, 48.0),
     ));

packages/flutter/test/widgets/image_icon_test.dart

@@ -111,7 +111,7 @@ void main() {
       ),
     );
 
-    expect(tester.getSemanticsData(find.byType(ImageIcon)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(ImageIcon)), matchesSemantics(
       label: 'test',
       textDirection: TextDirection.ltr,
     ));

packages/flutter/test/widgets/semantics_test.dart

@@ -643,7 +643,7 @@ void main() {
       onTapHint: 'test',
     ));
 
-    expect(tester.getSemanticsData(find.byType(Semantics)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(Semantics)), matchesSemantics(
       hasTapAction: true,
       onTapHint: 'test'
     ));
@@ -654,7 +654,7 @@ void main() {
       onLongPressHint: 'foo',
     ));
 
-    expect(tester.getSemanticsData(find.byType(Semantics)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(Semantics)), matchesSemantics(
       hasLongPressAction: true,
       onLongPressHint: 'foo'
     ));
@@ -671,7 +671,7 @@ void main() {
       },
     ));
 
-    expect(tester.getSemanticsData(find.byType(Semantics)), matchesSemanticsData(
+    expect(tester.getSemantics(find.byType(Semantics)), matchesSemantics(
       customActions: <CustomSemanticsAction>[
         const CustomSemanticsAction(label: 'bar'),
         const CustomSemanticsAction(label: 'foo'),

packages/flutter_test/lib/src/widget_tester.dart

@@ -617,15 +617,39 @@ class WidgetTester extends WidgetController implements HitTestDispatcher, Ticker
     });
   }
 
-  /// Attempts to find the [SemanticsData] of first result from `finder`.
+  /// Attempts to find the [SemanticsNode] of first result from `finder`.
   ///
   /// If the object identified by the finder doesn't own it's semantic node,
-  /// this will return the semantics data of the first ancestor with semantics
-  /// data. The ancestor's semantic data will include the child's as well as
+  /// this will return the semantics data of the first ancestor with semantics.
+  /// The ancestor's semantic data will include the child's as well as
   /// other nodes that have been merged together.
   ///
   /// Will throw a [StateError] if the finder returns more than one element or
   /// if no semantics are found or are not enabled.
+  SemanticsNode getSemantics(Finder finder) {
+    if (binding.pipelineOwner.semanticsOwner == null)
+      throw StateError('Semantics are not enabled.');
+    final Iterable<Element> candidates = finder.evaluate();
+    if (candidates.isEmpty) {
+      throw StateError('Finder returned no matching elements.');
+    }
+    if (candidates.length > 1) {
+      throw StateError('Finder returned more than one element.');
+    }
+    final Element element = candidates.single;
+    RenderObject renderObject = element.findRenderObject();
+    SemanticsNode result = renderObject.debugSemantics;
+    while (renderObject != null && result == null) {
+      renderObject = renderObject?.parent;
+      result = renderObject?.debugSemantics;
+    }
+    if (result == null)
+      throw StateError('No Semantics data found.');
+    return result;
+  }
+
+  /// DEPRECATED: use [getSemantics] instead.
+  @Deprecated('use getSemantics instead')
   SemanticsData getSemanticsData(Finder finder) {
     if (binding.pipelineOwner.semanticsOwner == null)
       throw StateError('Semantics are not enabled.');

packages/flutter_test/test/matchers_test.dart

@@ -409,8 +409,8 @@ void main() {
         },
       ));
 
-      expect(tester.getSemanticsData(find.byKey(key)),
-        matchesSemanticsData(
+      expect(tester.getSemantics(find.byKey(key)),
+        matchesSemantics(
           label: 'foo',
           hint: 'bar',
           value: 'baz',
@@ -432,8 +432,8 @@ void main() {
       );
 
       // Doesn't match custom actions
-      expect(tester.getSemanticsData(find.byKey(key)),
-        isNot(matchesSemanticsData(
+      expect(tester.getSemantics(find.byKey(key)),
+        isNot(matchesSemantics(
           label: 'foo',
           hint: 'bar',
           value: 'baz',
@@ -453,8 +453,8 @@ void main() {
       );
 
       // Doesn't match wrong hints
-      expect(tester.getSemanticsData(find.byKey(key)),
-        isNot(matchesSemanticsData(
+      expect(tester.getSemantics(find.byKey(key)),
+        isNot(matchesSemantics(
           label: 'foo',
           hint: 'bar',
           value: 'baz',
@@ -500,8 +500,10 @@ void main() {
         scrollExtentMin: null,
         customSemanticsActionIds: <int>[CustomSemanticsAction.getIdentifier(action)],
       );
+      final _FakeSemanticsNode node = _FakeSemanticsNode();
+      node.data = data;
 
-      expect(data, matchesSemanticsData(
+      expect(node, matchesSemantics(
          rect: Rect.fromLTRB(0.0, 0.0, 10.0, 10.0),
          size: const Size(10.0, 10.0),
          /* Flags */
@@ -548,6 +550,35 @@ void main() {
          customActions: <CustomSemanticsAction>[action],
       ));
     });
+
+    testWidgets('Can match child semantics', (WidgetTester tester) async {
+      final SemanticsHandle handle = tester.ensureSemantics();
+      const Key key = Key('a');
+      await tester.pumpWidget(Semantics(
+        key: key,
+        label: 'Foo',
+        container: true,
+        explicitChildNodes: true,
+        textDirection: TextDirection.ltr,
+        child: Semantics(
+          label: 'Bar',
+          textDirection: TextDirection.ltr,
+        ),
+      ));
+      final SemanticsNode node = tester.getSemantics(find.byKey(key));
+
+      expect(node, matchesSemantics(
+        label: 'Foo',
+        textDirection: TextDirection.ltr,
+        children: <Matcher>[
+          matchesSemantics(
+            label: 'Bar',
+            textDirection: TextDirection.ltr,
+          ),
+        ],
+      ));
+      handle.dispose();
+    });
   });
 }
 
@@ -592,3 +623,9 @@ class _FakeComparator implements GoldenFileComparator {
     return Future<void>.value();
   }
 }
+
+class _FakeSemanticsNode extends SemanticsNode {
+  SemanticsData data;
+  @override
+  SemanticsData getSemanticsData() => data;
+}
\ No newline at end of file

packages/flutter_test/test/widget_tester_test.dart

@@ -540,7 +540,7 @@ void main() {
         ),
       );
 
-      expect(() => tester.getSemanticsData(find.text('hello')),
+      expect(() => tester.getSemantics(find.text('hello')),
         throwsA(isInstanceOf<StateError>()));
     });
 
@@ -560,7 +560,7 @@ void main() {
         ),
       );
 
-      expect(() => tester.getSemanticsData(find.text('hello')),
+      expect(() => tester.getSemantics(find.text('hello')),
           throwsA(isInstanceOf<StateError>()));
       semanticsHandle.dispose();
     });
@@ -581,7 +581,8 @@ void main() {
         ),
       );
 
-      final SemanticsData semantics = tester.getSemanticsData(find.text('hello'));
+      final SemanticsNode node = tester.getSemantics(find.text('hello'));
+      final SemanticsData semantics = node.getSemanticsData();
       expect(semantics.label, 'hello');
       expect(semantics.hasAction(SemanticsAction.tap), true);
       expect(semantics.hasFlag(SemanticsFlag.isButton), true);
@@ -609,7 +610,8 @@ void main() {
         ),
       );
 
-      final SemanticsData semantics = tester.getSemanticsData(find.byKey(key));
+      final SemanticsNode node = tester.getSemantics(find.byKey(key));
+      final SemanticsData semantics = node.getSemanticsData();
       expect(semantics.label, 'A\nB\nC');
       semanticsHandle.dispose();
     });