wire bold text flag to text widget (#21325)

packages/flutter/lib/src/widgets/media_query.dart

@@ -46,6 +46,7 @@ class MediaQueryData {
     this.accessibleNavigation = false,
     this.invertColors = false,
     this.disableAnimations = false,
+    this.boldText = false,
   });
 
   /// Creates data for a media query based on the given window.
@@ -63,6 +64,7 @@ class MediaQueryData {
       accessibleNavigation = window.accessibilityFeatures.accessibleNavigation,
       invertColors = window.accessibilityFeatures.accessibleNavigation,
       disableAnimations = window.accessibilityFeatures.disableAnimations,
+      boldText = window.accessibilityFeatures.boldText,
       alwaysUse24HourFormat = window.alwaysUse24HourFormat;
 
   /// The size of the media in logical pixel (e.g, the size of the screen).
@@ -149,10 +151,20 @@ class MediaQueryData {
   /// Whether the platform is requesting that animations be disabled or reduced
   /// as much as possible.
   ///
+  /// See also:
+  ///
   ///  * [Window.AccessibilityFeatures], where the setting originates.
   ///
   final bool disableAnimations;
 
+  /// Whether the platform is requesting that text be drawn with a bold font
+  /// weight.
+  ///
+  /// See also:
+  ///
+  ///  * [Window.AccessibilityFeatures], where the setting originates.
+  final bool boldText;
+
   /// The orientation of the media (e.g., whether the device is in landscape or portrait mode).
   Orientation get orientation {
     return size.width > size.height ? Orientation.landscape : Orientation.portrait;
@@ -170,6 +182,7 @@ class MediaQueryData {
     bool disableAnimations,
     bool invertColors,
     bool accessibleNavigation,
+    bool boldText,
   }) {
     return new MediaQueryData(
       size: size ?? this.size,
@@ -181,6 +194,7 @@ class MediaQueryData {
       invertColors: invertColors ?? this.invertColors,
       disableAnimations: disableAnimations ?? this.disableAnimations,
       accessibleNavigation: accessibleNavigation ?? this.accessibleNavigation,
+      boldText: boldText ?? this.boldText,
     );
   }
 
@@ -221,6 +235,7 @@ class MediaQueryData {
       disableAnimations: disableAnimations,
       invertColors: invertColors,
       accessibleNavigation: accessibleNavigation,
+      boldText: boldText,
     );
   }
 
@@ -259,6 +274,7 @@ class MediaQueryData {
       disableAnimations: disableAnimations,
       invertColors: invertColors,
       accessibleNavigation: accessibleNavigation,
+      boldText: boldText,
     );
   }
 
@@ -275,7 +291,8 @@ class MediaQueryData {
         && typedOther.alwaysUse24HourFormat == alwaysUse24HourFormat
         && typedOther.disableAnimations == disableAnimations
         && typedOther.invertColors == invertColors
-        && typedOther.accessibleNavigation == accessibleNavigation;
+        && typedOther.accessibleNavigation == accessibleNavigation
+        && typedOther.boldText == boldText;
   }
 
   @override
@@ -290,6 +307,7 @@ class MediaQueryData {
       disableAnimations,
       invertColors,
       accessibleNavigation,
+      boldText,
     );
   }
 
@@ -305,6 +323,7 @@ class MediaQueryData {
              'accessibleNavigation: $accessibleNavigation'
              'disableAnimations: $disableAnimations'
              'invertColors: $invertColors'
+             'boldText: $boldText'
            ')';
   }
 }
@@ -476,6 +495,12 @@ class MediaQuery extends InheritedWidget {
     return MediaQuery.of(context, nullOk: true)?.textScaleFactor ?? 1.0;
   }
 
+  /// Returns the boldText accessibility setting for the nearest MediaQuery
+  /// ancestor, or false if no such ancestor exists.
+  static bool boldTextOverride(BuildContext context) {
+    return MediaQuery.of(context, nullOk: true)?.boldText ?? false;
+  }
+
   @override
   bool updateShouldNotify(MediaQuery oldWidget) => data != oldWidget.data;
 

packages/flutter/lib/src/widgets/text.dart

@@ -327,7 +327,7 @@ class Text extends StatelessWidget {
   /// If present, the semantics of this widget will contain this value instead
   /// of the actual text.
   ///
-  /// This is useful for replacing abbreviations or shorthands will the full
+  /// This is useful for replacing abbreviations or shorthands with the full
   /// text value:
   ///
   /// ```dart
@@ -342,6 +342,8 @@ class Text extends StatelessWidget {
     TextStyle effectiveTextStyle = style;
     if (style == null || style.inherit)
       effectiveTextStyle = defaultTextStyle.style.merge(style);
+    if (MediaQuery.boldTextOverride(context))
+      effectiveTextStyle = effectiveTextStyle.merge(const TextStyle(fontWeight: FontWeight.bold));
     Widget result = new RichText(
       textAlign: textAlign ?? defaultTextStyle.textAlign ?? TextAlign.start,
       textDirection: textDirection, // RichText uses Directionality.of to obtain a default if this is null.

packages/flutter/test/widgets/media_query_test.dart

@@ -46,6 +46,7 @@ void main() {
     expect(data.accessibleNavigation, false);
     expect(data.invertColors, false);
     expect(data.disableAnimations, false);
+    expect(data.boldText, false);
   });
 
   testWidgets('MediaQueryData.copyWith defaults to source', (WidgetTester tester) async {
@@ -60,6 +61,7 @@ void main() {
     expect(copied.accessibleNavigation, data.accessibleNavigation);
     expect(copied.invertColors, data.invertColors);
     expect(copied.disableAnimations, data.disableAnimations);
+    expect(copied.boldText, data.boldText);
   });
 
   testWidgets('MediaQuery.copyWith copies specified values', (WidgetTester tester) async {
@@ -74,6 +76,7 @@ void main() {
       accessibleNavigation: true,
       invertColors: true,
       disableAnimations: true,
+      boldText: true,
     );
     expect(copied.size, const Size(3.14, 2.72));
     expect(copied.devicePixelRatio, 1.41);
@@ -84,6 +87,7 @@ void main() {
     expect(copied.accessibleNavigation, true);
     expect(copied.invertColors, true);
     expect(copied.disableAnimations, true);
+    expect(copied.boldText, true);
   });
 
  testWidgets('MediaQuery.removePadding removes specified padding', (WidgetTester tester) async {
@@ -106,6 +110,7 @@ void main() {
          accessibleNavigation: true,
          invertColors: true,
          disableAnimations: true,
+         boldText: true,
        ),
        child: new Builder(
          builder: (BuildContext context) {
@@ -136,6 +141,7 @@ void main() {
    expect(unpadded.accessibleNavigation, true);
    expect(unpadded.invertColors, true);
    expect(unpadded.disableAnimations, true);
+   expect(unpadded.boldText, true);
   });
 
   testWidgets('MediaQuery.removeViewInsets removes specified viewInsets', (WidgetTester tester) async {
@@ -158,6 +164,7 @@ void main() {
           accessibleNavigation: true,
           invertColors: true,
           disableAnimations: true,
+          boldText: true,
         ),
         child: new Builder(
           builder: (BuildContext context) {
@@ -188,6 +195,7 @@ void main() {
     expect(unpadded.accessibleNavigation, true);
     expect(unpadded.invertColors, true);
     expect(unpadded.disableAnimations, true);
+    expect(unpadded.boldText, true);
   });
 
  testWidgets('MediaQuery.textScaleFactorOf', (WidgetTester tester) async {
@@ -216,4 +224,31 @@ void main() {
    expect(outsideTextScaleFactor, 1.0);
    expect(insideTextScaleFactor, 4.0);
  });
+
+  testWidgets('MediaQuery.boldTextOverride', (WidgetTester tester) async {
+    bool outsideBoldTextOverride;
+    bool insideBoldTextOverride;
+
+    await tester.pumpWidget(
+      new Builder(
+        builder: (BuildContext context) {
+          outsideBoldTextOverride = MediaQuery.boldTextOverride(context);
+          return new MediaQuery(
+            data: const MediaQueryData(
+              boldText: true,
+            ),
+            child: new Builder(
+              builder: (BuildContext context) {
+                insideBoldTextOverride = MediaQuery.boldTextOverride(context);
+                return new Container();
+              },
+            ),
+          );
+        },
+      ),
+    );
+
+    expect(outsideBoldTextOverride, false);
+    expect(insideBoldTextOverride, true);
+  });
 }