fix tree (#67410)

packages/flutter/test/cupertino/action_sheet_test.dart

@@ -61,7 +61,7 @@ void main() {
 
     final DefaultTextStyle widget = tester.widget(find.widgetWithText(DefaultTextStyle, 'Ok'));
 
-    expect(widget.style!.color, const CupertinoDynamicColor.withBrightnessAndContrast(
+    expect(widget.style.color, const CupertinoDynamicColor.withBrightnessAndContrast(
       color: Color.fromARGB(255, 255, 59, 48),
       darkColor: Color.fromARGB(255, 255, 69, 58),
       highContrastColor: Color.fromARGB(255, 215, 0, 21),
@@ -84,7 +84,7 @@ void main() {
           of: find.widgetWithText(CupertinoActionSheetAction, text),
           matching: find.byType(DefaultTextStyle),
         ),
-      ).style!;
+      ).style;
     }
 
     await tester.pumpWidget(
@@ -139,7 +139,7 @@ void main() {
 
     final DefaultTextStyle widget = tester.widget(find.widgetWithText(DefaultTextStyle, 'Ok'));
 
-    expect(widget.style!.fontWeight, equals(FontWeight.w600));
+    expect(widget.style.fontWeight, equals(FontWeight.w600));
   });
 
   testWidgets('Action sheet text styles are correct when both title and message are included', (WidgetTester tester) async {
@@ -160,8 +160,8 @@ void main() {
     final DefaultTextStyle messageStyle = tester.firstWidget(find.widgetWithText(DefaultTextStyle,
         'An action sheet'));
 
-    expect(titleStyle.style!.fontWeight, FontWeight.w600);
-    expect(messageStyle.style!.fontWeight, FontWeight.w400);
+    expect(titleStyle.style.fontWeight, FontWeight.w600);
+    expect(messageStyle.style.fontWeight, FontWeight.w400);
   });
 
   testWidgets('Action sheet text styles are correct when title but no message is included', (WidgetTester tester) async {
@@ -179,7 +179,7 @@ void main() {
     final DefaultTextStyle titleStyle = tester.firstWidget(find.widgetWithText(DefaultTextStyle,
         'Action Sheet'));
 
-    expect(titleStyle.style!.fontWeight, FontWeight.w400);
+    expect(titleStyle.style.fontWeight, FontWeight.w400);
   });
 
   testWidgets('Action sheet text styles are correct when message but no title is included', (WidgetTester tester) async {
@@ -197,7 +197,7 @@ void main() {
     final DefaultTextStyle messageStyle = tester.firstWidget(find.widgetWithText(DefaultTextStyle,
         'An action sheet'));
 
-    expect(messageStyle.style!.fontWeight, FontWeight.w600);
+    expect(messageStyle.style.fontWeight, FontWeight.w600);
   });
 
   testWidgets('Content section but no actions', (WidgetTester tester) async {

packages/flutter/test/cupertino/button_test.dart

@@ -323,7 +323,7 @@ void main() {
         home: CupertinoButton(
           onPressed: () { },
           child: Builder(builder: (BuildContext context) {
-            textStyle = DefaultTextStyle.of(context).style!;
+            textStyle = DefaultTextStyle.of(context).style;
             return const Placeholder();
           }),
         ),
@@ -337,7 +337,7 @@ void main() {
         home: CupertinoButton.filled(
           onPressed: () { },
           child: Builder(builder: (BuildContext context) {
-            textStyle = DefaultTextStyle.of(context).style!;
+            textStyle = DefaultTextStyle.of(context).style;
             return const Placeholder();
           }),
         ),
@@ -359,7 +359,7 @@ void main() {
         home: CupertinoButton(
           onPressed: () { },
           child: Builder(builder: (BuildContext context) {
-            textStyle = DefaultTextStyle.of(context).style!;
+            textStyle = DefaultTextStyle.of(context).style;
             return const Placeholder();
           }),
         ),
@@ -373,7 +373,7 @@ void main() {
         home: CupertinoButton.filled(
           onPressed: () { },
           child: Builder(builder: (BuildContext context) {
-            textStyle = DefaultTextStyle.of(context).style!;
+            textStyle = DefaultTextStyle.of(context).style;
             return const Placeholder();
           }),
         ),

packages/flutter/test/cupertino/context_menu_action_test.dart

@@ -50,7 +50,7 @@ void main() {
     );
     expect(finder, findsOneWidget);
     final DefaultTextStyle defaultStyle = tester.widget(finder);
-    return defaultStyle.style!;
+    return defaultStyle.style;
   }
 
   Icon _getIcon(WidgetTester tester) {

packages/flutter/test/cupertino/dialog_test.dart

@@ -116,7 +116,7 @@ void main() {
 
     final DefaultTextStyle widget = tester.widget(find.byType(DefaultTextStyle));
 
-    expect(widget.style!.color!.withAlpha(255), CupertinoColors.systemRed.color);
+    expect(widget.style.color!.withAlpha(255), CupertinoColors.systemRed.color);
   });
 
   testWidgets('Dialog dark theme', (WidgetTester tester) async {
@@ -231,7 +231,7 @@ void main() {
 
     final DefaultTextStyle widget = tester.widget(find.byType(DefaultTextStyle));
 
-    expect(widget.style!.fontWeight, equals(FontWeight.w600));
+    expect(widget.style.fontWeight, equals(FontWeight.w600));
   });
 
   testWidgets('Dialog default and destructive action styles', (WidgetTester tester) async {
@@ -243,8 +243,8 @@ void main() {
 
     final DefaultTextStyle widget = tester.widget(find.byType(DefaultTextStyle));
 
-    expect(widget.style!.color!.withAlpha(255), CupertinoColors.systemRed.color);
-    expect(widget.style!.fontWeight, equals(FontWeight.w600));
+    expect(widget.style.color!.withAlpha(255), CupertinoColors.systemRed.color);
+    expect(widget.style.fontWeight, equals(FontWeight.w600));
   });
 
   testWidgets('Dialog disabled action style', (WidgetTester tester) async {
@@ -254,8 +254,8 @@ void main() {
 
     final DefaultTextStyle widget = tester.widget(find.byType(DefaultTextStyle));
 
-    expect(widget.style!.color!.opacity, greaterThanOrEqualTo(127 / 255));
-    expect(widget.style!.color!.opacity, lessThanOrEqualTo(128 / 255));
+    expect(widget.style.color!.opacity, greaterThanOrEqualTo(127 / 255));
+    expect(widget.style.color!.opacity, lessThanOrEqualTo(128 / 255));
   });
 
   testWidgets('Dialog enabled action style', (WidgetTester tester) async {
@@ -266,7 +266,7 @@ void main() {
 
     final DefaultTextStyle widget = tester.widget(find.byType(DefaultTextStyle));
 
-    expect(widget.style!.color!.opacity, equals(1.0));
+    expect(widget.style.color!.opacity, equals(1.0));
   });
 
   testWidgets('Message is scrollable, has correct padding with large text sizes', (WidgetTester tester) async {

packages/flutter/test/cupertino/nav_bar_test.dart

@@ -1198,7 +1198,7 @@ class _ExpectStyles extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final TextStyle style = DefaultTextStyle.of(context).style!;
+    final TextStyle style = DefaultTextStyle.of(context).style;
     expect(style.color, isSameColorAs(color));
     expect(style.fontFamily, '.SF Pro Text');
     expect(style.fontSize, 17.0);