Fix hint and label contrast test failures by prioritizing them in InputDecorator hit testing

QuncCccccc · QuncCccccc · commit b63678ae563b · 2026-04-09T13:12:42.000-07:00
diff --git a/packages/flutter/lib/src/material/input_decorator.dart b/packages/flutter/lib/src/material/input_decorator.dart
@@ -756,18 +756,22 @@ class _RenderDecoration extends RenderBox
   RenderBox? get container => childForSlot(_DecorationSlot.container);
 
   // The returned list is ordered for hit testing.
+  // Prioritize hint when not focused to make it hit-testable for accessibility
+  // guidelines.
   @override
   Iterable<RenderBox> get children {
     final RenderBox? helperError = childForSlot(_DecorationSlot.helperError);
     return <RenderBox>[
       ?icon,
-      ?input,
+      if (!isFocused) ?hint,
+      if (!isFocused) ?label,
       ?prefixIcon,
       ?suffixIcon,
       ?prefix,
       ?suffix,
-      ?label,
-      ?hint,
+      ?input,
+      if (isFocused) ?label,
+      if (isFocused) ?hint,
       ?helperError,
       ?counter,
       ?container,
@@ -1808,7 +1812,6 @@ class _AffixText extends StatelessWidget {
     this.style,
     this.child,
     this.semanticsSortKey,
-    this.semanticsEnabled,
     required this.semanticsTag,
   });
 
@@ -1817,7 +1820,6 @@ class _AffixText extends StatelessWidget {
   final TextStyle? style;
   final Widget? child;
   final SemanticsSortKey? semanticsSortKey;
-  final bool? semanticsEnabled;
   final SemanticsTag semanticsTag;
 
   @override
@@ -1833,7 +1835,6 @@ class _AffixText extends StatelessWidget {
           child: Semantics(
             sortKey: semanticsSortKey,
             tagForChildren: semanticsTag,
-            enabled: semanticsEnabled,
             child: child ?? (text == null ? null : Text(text!, style: style)),
           ),
         ),
@@ -2428,7 +2429,6 @@ class _InputDecoratorState extends State<InputDecorator> with TickerProviderStat
             style: WidgetStateProperty.resolveAs(decoration.prefixStyle, widgetState) ?? hintStyle,
             semanticsSortKey: needsSemanticsSortOrder ? _prefixSemanticsSortOrder : null,
             semanticsTag: _kPrefixSemanticsTag,
-            semanticsEnabled: decoration.enabled,
             child: decoration.prefix,
           )
         : null;
@@ -2440,7 +2440,6 @@ class _InputDecoratorState extends State<InputDecorator> with TickerProviderStat
             style: WidgetStateProperty.resolveAs(decoration.suffixStyle, widgetState) ?? hintStyle,
             semanticsSortKey: needsSemanticsSortOrder ? _suffixSemanticsSortOrder : null,
             semanticsTag: _kSuffixSemanticsTag,
-            semanticsEnabled: decoration.enabled,
             child: decoration.suffix,
           )
         : null;
diff --git a/packages/flutter/test/material/text_field_test.dart b/packages/flutter/test/material/text_field_test.dart
@@ -5653,12 +5653,7 @@ void main() {
           children: <TestSemantics>[
             TestSemantics(
               children: <TestSemantics>[
-                TestSemantics(
-                  id: 2,
-                  textDirection: TextDirection.ltr,
-                  flags: <SemanticsFlag>[SemanticsFlag.hasEnabledState, SemanticsFlag.isEnabled],
-                  label: 'Prefix',
-                ),
+                TestSemantics(id: 2, textDirection: TextDirection.ltr, label: 'Prefix'),
                 TestSemantics(
                   textDirection: TextDirection.ltr,
                   value: 'some text',
@@ -5672,12 +5667,7 @@ void main() {
                     SemanticsFlag.isEnabled,
                   ],
                 ),
-                TestSemantics(
-                  id: 3,
-                  textDirection: TextDirection.ltr,
-                  flags: <SemanticsFlag>[SemanticsFlag.hasEnabledState, SemanticsFlag.isEnabled],
-                  label: 'Suffix',
-                ),
+                TestSemantics(id: 3, textDirection: TextDirection.ltr, label: 'Suffix'),
               ],
             ),
           ],
diff --git a/packages/flutter_test/lib/src/accessibility.dart b/packages/flutter_test/lib/src/accessibility.dart
@@ -335,53 +335,6 @@ class MinimumTextContrastGuideline extends AccessibilityGuideline {
     return result;
   }
 
-  /// Determines if the given [element] is currently visible on screen and
-  /// not occluded by other unrelated UI layers.
-  ///
-  /// This method is similar to [Finder.hitTestable], as it performs a hit test
-  /// at the center of the element. However, instead of strictly requiring the
-  /// element's render object to be an ancestor of the hit target (which fails
-  /// for siblings like `TextField` hints that delegate hits to other parts of
-  /// the same component), it returns true if any render object in the hit
-  /// path shares the same [debugSemantics] node. This allows testing
-  /// non-interactive visual parts of interactive widgets while successfully
-  /// rejecting elements truly occluded by completely separate overlapping layers.
-  bool _isElementVisible(Element element, SemanticsNode node) {
-    final RenderObject? object = element.renderObject;
-    if (object is! RenderBox) {
-      return false;
-    }
-    final int viewId = element.findAncestorWidgetOfExactType<View>()!.view.viewId;
-    final Offset absoluteOffset = object.localToGlobal(object.size.center(Offset.zero));
-    final hitResult = HitTestResult();
-    WidgetsBinding.instance.hitTestInView(hitResult, absoluteOffset, viewId);
-
-    if (hitResult.path.isEmpty) {
-      return false;
-    }
-
-    // Find the first RenderObject in the hit path to ensure we respect occlusion
-    // while properly handling non-RenderObject targets like TextSpan.
-    RenderObject? topRenderObject;
-    for (final HitTestEntry entry in hitResult.path) {
-      if (entry.target is RenderObject) {
-        topRenderObject = entry.target as RenderObject;
-        break;
-      }
-    }
-
-    if (topRenderObject != null) {
-       RenderObject? current = topRenderObject;
-       while (current != null) {
-         if (current == object || current.debugSemantics == node) {
-           return true;
-         }
-         current = current.parent;
-       }
-    }
-    return false;
-  }
-
   Future<Evaluation> _evaluateNode(
     SemanticsNode node,
     WidgetTester tester,
@@ -414,11 +367,9 @@ class MinimumTextContrastGuideline extends AccessibilityGuideline {
       return result;
     }
     final String text = data.label.isEmpty ? data.value : data.label;
-    final Iterable<Element> elements = find.text(text).evaluate();
+    final Iterable<Element> elements = find.text(text).hitTestable().evaluate();
     for (final element in elements) {
-      if (_isElementVisible(element, node)) {
-        result += await _evaluateElement(node, element, tester, image, byteData, renderView);
-      }
+      result += await _evaluateElement(node, element, tester, image, byteData, renderView);
     }
     return result;
   }
diff --git a/packages/flutter_test/test/accessibility_test.dart b/packages/flutter_test/test/accessibility_test.dart
@@ -248,7 +248,9 @@ void main() {
       handle.dispose();
     });
 
-    testWidgets('Material text field - hint text contrast', (WidgetTester tester) async {
+    testWidgets('TextField hint text with insufficient contrast fails', (
+      WidgetTester tester,
+    ) async {
       final SemanticsHandle handle = tester.ensureSemantics();
       await tester.pumpWidget(
         _boilerplate(
@@ -270,6 +272,91 @@ void main() {
       handle.dispose();
     });
 
+    testWidgets('TextField hint text with sufficient contrast passes', (WidgetTester tester) async {
+      final SemanticsHandle handle = tester.ensureSemantics();
+      await tester.pumpWidget(
+        _boilerplate(
+          const SizedBox(
+            width: 200.0,
+            child: TextField(decoration: InputDecoration(hintText: 'Enter text')),
+          ),
+        ),
+      );
+      await expectLater(tester, meetsGuideline(textContrastGuideline));
+      handle.dispose();
+    });
+
+    testWidgets('TextField label text with insufficient contrast fails', (
+      WidgetTester tester,
+    ) async {
+      final SemanticsHandle handle = tester.ensureSemantics();
+      await tester.pumpWidget(
+        _boilerplate(
+          SizedBox(
+            width: 200.0,
+            child: TextField(
+              decoration: InputDecoration(
+                labelText: 'Email',
+                labelStyle: TextStyle(color: Colors.white.withAlpha(32)),
+              ),
+            ),
+          ),
+        ),
+      );
+      await expectLater(tester, doesNotMeetGuideline(textContrastGuideline));
+      handle.dispose();
+    });
+
+    testWidgets('Disabled TextField hint text is excluded from contrast check', (
+      WidgetTester tester,
+    ) async {
+      final SemanticsHandle handle = tester.ensureSemantics();
+      await tester.pumpWidget(
+        _boilerplate(
+          SizedBox(
+            width: 200.0,
+            child: TextField(
+              enabled: false,
+              decoration: InputDecoration(
+                hintText: 'Enter text',
+                hintStyle: TextStyle(color: Colors.white.withAlpha(32)),
+              ),
+            ),
+          ),
+        ),
+      );
+      await expectLater(tester, meetsGuideline(textContrastGuideline));
+      handle.dispose();
+    });
+
+    testWidgets('Text occluded by another widget is excluded from contrast check', (
+      WidgetTester tester,
+    ) async {
+      final SemanticsHandle handle = tester.ensureSemantics();
+      await tester.pumpWidget(
+        _boilerplate(
+          SizedBox(
+            width: 200.0,
+            height: 200.0,
+            child: Stack(
+              children: <Widget>[
+                // Text behind an opaque container — visually occluded.
+                const Positioned.fill(
+                  child: Text(
+                    'hidden text',
+                    style: TextStyle(fontSize: 14.0, color: Colors.yellowAccent),
+                  ),
+                ),
+                Positioned.fill(child: Container(color: Colors.white)),
+              ],
+            ),
+          ),
+        ),
+      );
+      await expectLater(tester, meetsGuideline(textContrastGuideline));
+      handle.dispose();
+    });
+
     testWidgets('Material2: yellow text on yellow background fails with correct message', (
       WidgetTester tester,
     ) async {
@@ -453,6 +540,7 @@ void main() {
       handle.dispose();
     });
 
+
     testWidgets('Disabled button is excluded from text contrast guideline', (
       WidgetTester tester,
     ) async {
