packages/flutter/test/material/theme_test.dart - external/github.com/flutter/flutter - Git at Google

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 import 'dart:ui' as ui;
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/src/foundation/diagnostics.dart';
 import 'package:flutter_test/flutter_test.dart';

 void main() {
   test('ThemeDataTween control test', () {
     final ThemeData light = ThemeData.light();
     final ThemeData dark = ThemeData.dark();
     final ThemeDataTween tween = ThemeDataTween(begin: light, end: dark);
     expect(tween.lerp(0.25), equals(ThemeData.lerp(light, dark, 0.25)));
   });

   testWidgets('PopupMenu inherits app theme', (WidgetTester tester) async {
     final Key popupMenuButtonKey = UniqueKey();
     await tester.pumpWidget(
       MaterialApp(
         theme: ThemeData(brightness: Brightness.dark),
         home: Scaffold(
           appBar: AppBar(
             actions: <Widget>[
               PopupMenuButton<String>(
                 key: popupMenuButtonKey,
                 itemBuilder: (BuildContext context) {
                   return <PopupMenuItem<String>>[
                     const PopupMenuItem<String>(child: Text('menuItem'))
                   ];
                 }
               ),
             ]
           )
         )
       )
     );

     await tester.tap(find.byKey(popupMenuButtonKey));
     await tester.pump(const Duration(seconds: 1));

     expect(Theme.of(tester.element(find.text('menuItem'))).brightness, equals(Brightness.dark));
   });

   testWidgets('Fallback theme', (WidgetTester tester) async {
     BuildContext capturedContext;
     await tester.pumpWidget(
       Builder(
         builder: (BuildContext context) {
           capturedContext = context;
           return Container();
         }
       )
     );

     expect(Theme.of(capturedContext), equals(ThemeData.localize(ThemeData.fallback(), MaterialTextGeometry.englishLike)));
     expect(Theme.of(capturedContext, shadowThemeOnly: true), isNull);
   });

   testWidgets('ThemeData.localize memoizes the result', (WidgetTester tester) async {
     final ThemeData light = ThemeData.light();
     final ThemeData dark = ThemeData.dark();

     // Same input, same output.
     expect(
       ThemeData.localize(light, MaterialTextGeometry.englishLike),
       same(ThemeData.localize(light, MaterialTextGeometry.englishLike)),
     );

     // Different text geometry, different output.
     expect(
       ThemeData.localize(light, MaterialTextGeometry.englishLike),
       isNot(same(ThemeData.localize(light, MaterialTextGeometry.tall))),
     );

     // Different base theme, different output.
     expect(
       ThemeData.localize(light, MaterialTextGeometry.englishLike),
       isNot(same(ThemeData.localize(dark, MaterialTextGeometry.englishLike))),
     );
   });

   testWidgets('PopupMenu inherits shadowed app theme', (WidgetTester tester) async {
     // Regression test for https://github.com/flutter/flutter/issues/5572
     final Key popupMenuButtonKey = UniqueKey();
     await tester.pumpWidget(
       MaterialApp(
         theme: ThemeData(brightness: Brightness.dark),
         home: Theme(
           data: ThemeData(brightness: Brightness.light),
           child: Scaffold(
             appBar: AppBar(
               actions: <Widget>[
                 PopupMenuButton<String>(
                   key: popupMenuButtonKey,
                   itemBuilder: (BuildContext context) {
                     return <PopupMenuItem<String>>[
                       const PopupMenuItem<String>(child: Text('menuItem'))
                     ];
                   }
                 ),
               ]
             )
           )
         )
       )
     );

     await tester.tap(find.byKey(popupMenuButtonKey));
     await tester.pump(const Duration(seconds: 1));

     expect(Theme.of(tester.element(find.text('menuItem'))).brightness, equals(Brightness.light));
   });

   testWidgets('DropdownMenu inherits shadowed app theme', (WidgetTester tester) async {
     final Key dropdownMenuButtonKey = UniqueKey();
     await tester.pumpWidget(
       MaterialApp(
         theme: ThemeData(brightness: Brightness.dark),
         home: Theme(
           data: ThemeData(brightness: Brightness.light),
           child: Scaffold(
             appBar: AppBar(
               actions: <Widget>[
                 DropdownButton<String>(
                   key: dropdownMenuButtonKey,
                   onChanged: (String newValue) { },
                   value: 'menuItem',
                   items: const <DropdownMenuItem<String>>[
                     DropdownMenuItem<String>(
                       value: 'menuItem',
                       child: Text('menuItem'),
                     ),
                   ],
                 )
               ]
             )
           )
         )
       )
     );

     await tester.tap(find.byKey(dropdownMenuButtonKey));
     await tester.pump(const Duration(seconds: 1));

     for (Element item in tester.elementList(find.text('menuItem')))
       expect(Theme.of(item).brightness, equals(Brightness.light));
   });

   testWidgets('ModalBottomSheet inherits shadowed app theme', (WidgetTester tester) async {
     await tester.pumpWidget(
       MaterialApp(
         theme: ThemeData(brightness: Brightness.dark),
         home: Theme(
           data: ThemeData(brightness: Brightness.light),
           child: Scaffold(
             body: Center(
               child: Builder(
                 builder: (BuildContext context) {
                   return RaisedButton(
                     onPressed: () {
                       showModalBottomSheet<void>(
                         context: context,
                         builder: (BuildContext context) => const Text('bottomSheet'),
                       );
                     },
                     child: const Text('SHOW'),
                   );
                 }
               )
             )
           )
         )
       )
     );

     await tester.tap(find.text('SHOW'));
     await tester.pump(const Duration(seconds: 1));
     expect(Theme.of(tester.element(find.text('bottomSheet'))).brightness, equals(Brightness.light));

     await tester.tap(find.text('bottomSheet')); // dismiss the bottom sheet
     await tester.pump(const Duration(seconds: 1));
   });

   testWidgets('Dialog inherits shadowed app theme', (WidgetTester tester) async {
     final GlobalKey<ScaffoldState> scaffoldKey = GlobalKey<ScaffoldState>();
     await tester.pumpWidget(
       MaterialApp(
         theme: ThemeData(brightness: Brightness.dark),
         home: Theme(
           data: ThemeData(brightness: Brightness.light),
           child: Scaffold(
             key: scaffoldKey,
             body: Center(
               child: Builder(
                 builder: (BuildContext context) {
                   return RaisedButton(
                     onPressed: () {
                       showDialog<void>(
                         context: context,
                         builder: (BuildContext context) => const Text('dialog'),
                       );
                     },
                     child: const Text('SHOW'),
                   );
                 }
               )
             )
           )
         )
       )
     );

     await tester.tap(find.text('SHOW'));
     await tester.pump(const Duration(seconds: 1));
     expect(Theme.of(tester.element(find.text('dialog'))).brightness, equals(Brightness.light));
   });

   testWidgets("Scaffold inherits theme's scaffoldBackgroundColor", (WidgetTester tester) async {
     const Color green = Color(0xFF00FF00);

     await tester.pumpWidget(
       MaterialApp(
         theme: ThemeData(scaffoldBackgroundColor: green),
         home: Scaffold(
           body: Center(
             child: Builder(
               builder: (BuildContext context) {
                 return GestureDetector(
                   onTap: () {
                     showDialog<void>(
                       context: context,
                       builder: (BuildContext context) {
                         return const Scaffold(
                           body: SizedBox(
                             width: 200.0,
                             height: 200.0,
                           ),
                         );
                       },
                     );
                   },
                   child: const Text('SHOW'),
                 );
               },
             ),
           ),
         ),
       )
     );

     await tester.tap(find.text('SHOW'));
     await tester.pump(const Duration(seconds: 1));

     final List<Material> materials = tester.widgetList<Material>(find.byType(Material)).toList();
     expect(materials.length, equals(2));
     expect(materials[0].color, green); // app scaffold
     expect(materials[1].color, green); // dialog scaffold
   });

   testWidgets('IconThemes are applied', (WidgetTester tester) async {
     await tester.pumpWidget(
       MaterialApp(
         theme: ThemeData(iconTheme: const IconThemeData(color: Colors.green, size: 10.0)),
         home: const Icon(Icons.computer),
       )
     );

     RenderParagraph glyphText = tester.renderObject(find.byType(RichText));

     expect(glyphText.text.style.color, Colors.green);
     expect(glyphText.text.style.fontSize, 10.0);

     await tester.pumpWidget(
       MaterialApp(
         theme: ThemeData(iconTheme: const IconThemeData(color: Colors.orange, size: 20.0)),
         home: const Icon(Icons.computer),
       ),
     );
     await tester.pump(const Duration(milliseconds: 100)); // Halfway through the theme transition

     glyphText = tester.renderObject(find.byType(RichText));

     expect(glyphText.text.style.color, Color.lerp(Colors.green, Colors.orange, 0.5));
     expect(glyphText.text.style.fontSize, 15.0);

     await tester.pump(const Duration(milliseconds: 100)); // Finish the transition
     glyphText = tester.renderObject(find.byType(RichText));

     expect(glyphText.text.style.color, Colors.orange);
     expect(glyphText.text.style.fontSize, 20.0);
   });

   testWidgets(
     'Same ThemeData reapplied does not trigger descendants rebuilds',
     (WidgetTester tester) async {
       testBuildCalled = 0;
       ThemeData themeData = ThemeData(primaryColor: const Color(0xFF000000));

       Widget buildTheme() {
         return Theme(
           data: themeData,
           child: const Test(),
         );
       }

       await tester.pumpWidget(buildTheme());
       expect(testBuildCalled, 1);

       // Pump the same widgets again.
       await tester.pumpWidget(buildTheme());
       // No repeated build calls to the child since it's the same theme data.
       expect(testBuildCalled, 1);

       // New instance of theme data but still the same content.
       themeData = ThemeData(primaryColor: const Color(0xFF000000));
       await tester.pumpWidget(buildTheme());
       // Still no repeated calls.
       expect(testBuildCalled, 1);

       // Different now.
       themeData = ThemeData(primaryColor: const Color(0xFF222222));
       await tester.pumpWidget(buildTheme());
       // Should call build again.
       expect(testBuildCalled, 2);
     },
   );

   testWidgets('Text geometry set in Theme has higher precedence than that of Localizations', (WidgetTester tester) async {
     const double _kMagicFontSize = 4321.0;
     final ThemeData fallback = ThemeData.fallback();
     final ThemeData customTheme = fallback.copyWith(
       primaryTextTheme: fallback.primaryTextTheme.copyWith(
         body1: fallback.primaryTextTheme.body1.copyWith(
           fontSize: _kMagicFontSize,
         )
       ),
     );
     expect(customTheme.primaryTextTheme.body1.fontSize, _kMagicFontSize);

     double actualFontSize;
     await tester.pumpWidget(Directionality(
       textDirection: TextDirection.ltr,
       child: Theme(
         data: customTheme,
         child: Builder(builder: (BuildContext context) {
           final ThemeData theme = Theme.of(context);
           actualFontSize = theme.primaryTextTheme.body1.fontSize;
           return Text(
             'A',
             style: theme.primaryTextTheme.body1,
           );
         }),
       ),
     ));

     expect(actualFontSize, _kMagicFontSize);
   });

   testWidgets('Default Theme provides all basic TextStyle properties', (WidgetTester tester) async {
     ThemeData theme;
     await tester.pumpWidget(Directionality(
       textDirection: TextDirection.ltr,
       child: Builder(
         builder: (BuildContext context) {
           theme = Theme.of(context);
           return const Text('A');
         },
       ),
     ));

     List<TextStyle> extractStyles(TextTheme textTheme) {
       return <TextStyle>[
         textTheme.display4,
         textTheme.display3,
         textTheme.display2,
         textTheme.display1,
         textTheme.headline,
         textTheme.title,
         textTheme.subhead,
         textTheme.body2,
         textTheme.body1,
         textTheme.caption,
         textTheme.button,
       ];
     }

     for (TextTheme textTheme in <TextTheme>[theme.textTheme, theme.primaryTextTheme, theme.accentTextTheme]) {
       for (TextStyle style in extractStyles(textTheme).map((TextStyle style) => _TextStyleProxy(style))) {
         expect(style.inherit, false);
         expect(style.color, isNotNull);
         expect(style.fontFamily, isNotNull);
         expect(style.fontSize, isNotNull);
         expect(style.fontWeight, isNotNull);
         expect(style.fontStyle, null);
         expect(style.letterSpacing, null);
         expect(style.wordSpacing, null);
         expect(style.textBaseline, isNotNull);
         expect(style.height, null);
         expect(style.decoration, TextDecoration.none);
         expect(style.decorationColor, null);
         expect(style.decorationStyle, null);
         expect(style.debugLabel, isNotNull);
         expect(style.locale, null);
         expect(style.background, null);
       }
     }

     expect(theme.textTheme.display4.debugLabel, '(englishLike display4).merge(blackMountainView display4)');
   });
 }

 int testBuildCalled;
 class Test extends StatefulWidget {
   const Test();

   @override
   _TestState createState() => _TestState();
 }

 class _TestState extends State<Test> {
   @override
   Widget build(BuildContext context) {
     testBuildCalled += 1;
     return Container(
       decoration: BoxDecoration(
         color: Theme.of(context).primaryColor,
       ),
     );
   }
 }

 /// This class exists only to make sure that we test all the properties of the
 /// [TextStyle] class. If a property is added/removed/renamed, the analyzer will
 /// complain that this class has incorrect overrides.
 class _TextStyleProxy implements TextStyle {
   _TextStyleProxy(this._delegate);

   final TextStyle _delegate;

   // Do make sure that all the properties correctly forward to the _delegate.
   @override Color get color => _delegate.color;
   @override String get debugLabel => _delegate.debugLabel;
   @override TextDecoration get decoration => _delegate.decoration;
   @override Color get decorationColor => _delegate.decorationColor;
   @override TextDecorationStyle get decorationStyle => _delegate.decorationStyle;
   @override String get fontFamily => _delegate.fontFamily;
   @override double get fontSize => _delegate.fontSize;
   @override FontStyle get fontStyle => _delegate.fontStyle;
   @override FontWeight get fontWeight => _delegate.fontWeight;
   @override double get height => _delegate.height;
   @override Locale get locale => _delegate.locale;
   @override ui.Paint get foreground => _delegate.foreground;
   @override ui.Paint get background => _delegate.background;
   @override bool get inherit => _delegate.inherit;
   @override double get letterSpacing => _delegate.letterSpacing;
   @override TextBaseline get textBaseline => _delegate.textBaseline;
   @override double get wordSpacing => _delegate.wordSpacing;

   @override
   String toString({DiagnosticLevel minLevel = DiagnosticLevel.debug}) =>
       super.toString();

   @override
   DiagnosticsNode toDiagnosticsNode({String name, DiagnosticsTreeStyle style}) {
     throw UnimplementedError();
   }

   @override
   String toStringShort() {
     throw UnimplementedError();
   }

   @override
   TextStyle apply({Color color, TextDecoration decoration, Color decorationColor, TextDecorationStyle decorationStyle, String fontFamily, double fontSizeFactor = 1.0, double fontSizeDelta = 0.0, int fontWeightDelta = 0, double letterSpacingFactor = 1.0, double letterSpacingDelta = 0.0, double wordSpacingFactor = 1.0, double wordSpacingDelta = 0.0, double heightFactor = 1.0, double heightDelta = 0.0}) {
     throw UnimplementedError();
   }

   @override
   RenderComparison compareTo(TextStyle other) {
     throw UnimplementedError();
   }

   @override
   TextStyle copyWith({Color color, String fontFamily, double fontSize, FontWeight fontWeight, FontStyle fontStyle, double letterSpacing, double wordSpacing, TextBaseline textBaseline, double height, Locale locale, ui.Paint foreground, ui.Paint background, TextDecoration decoration, Color decorationColor, TextDecorationStyle decorationStyle, String debugLabel}) {
     throw UnimplementedError();
   }

   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties, {String prefix = ''}) {
     throw UnimplementedError();
   }

   @override
   ui.ParagraphStyle getParagraphStyle({TextAlign textAlign, TextDirection textDirection, double textScaleFactor = 1.0, String ellipsis, int maxLines, Locale locale}) {
     throw UnimplementedError();
   }

   @override
   ui.TextStyle getTextStyle({double textScaleFactor = 1.0}) {
     throw UnimplementedError();
   }

   @override
   TextStyle merge(TextStyle other) {
     throw UnimplementedError();
   }
 }
	// Copyright 2016 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	import 'dart:ui' as ui;
	import 'package:flutter/material.dart';
	import 'package:flutter/rendering.dart';
	import 'package:flutter/src/foundation/diagnostics.dart';
	import 'package:flutter_test/flutter_test.dart';

	void main() {
	test('ThemeDataTween control test', () {
	final ThemeData light = ThemeData.light();
	final ThemeData dark = ThemeData.dark();
	final ThemeDataTween tween = ThemeDataTween(begin: light, end: dark);
	expect(tween.lerp(0.25), equals(ThemeData.lerp(light, dark, 0.25)));
	});

	testWidgets('PopupMenu inherits app theme', (WidgetTester tester) async {
	final Key popupMenuButtonKey = UniqueKey();
	await tester.pumpWidget(
	MaterialApp(
	theme: ThemeData(brightness: Brightness.dark),
	home: Scaffold(
	appBar: AppBar(
	actions: <Widget>[
	PopupMenuButton<String>(
	key: popupMenuButtonKey,
	itemBuilder: (BuildContext context) {
	return <PopupMenuItem<String>>[
	const PopupMenuItem<String>(child: Text('menuItem'))
	];
	}
	),
	]
	)
	)
	)
	);

	await tester.tap(find.byKey(popupMenuButtonKey));
	await tester.pump(const Duration(seconds: 1));

	expect(Theme.of(tester.element(find.text('menuItem'))).brightness, equals(Brightness.dark));
	});

	testWidgets('Fallback theme', (WidgetTester tester) async {
	BuildContext capturedContext;
	await tester.pumpWidget(
	Builder(
	builder: (BuildContext context) {
	capturedContext = context;
	return Container();
	}
	)
	);

	expect(Theme.of(capturedContext), equals(ThemeData.localize(ThemeData.fallback(), MaterialTextGeometry.englishLike)));
	expect(Theme.of(capturedContext, shadowThemeOnly: true), isNull);
	});

	testWidgets('ThemeData.localize memoizes the result', (WidgetTester tester) async {
	final ThemeData light = ThemeData.light();
	final ThemeData dark = ThemeData.dark();

	// Same input, same output.
	expect(
	ThemeData.localize(light, MaterialTextGeometry.englishLike),
	same(ThemeData.localize(light, MaterialTextGeometry.englishLike)),
	);

	// Different text geometry, different output.
	expect(
	ThemeData.localize(light, MaterialTextGeometry.englishLike),
	isNot(same(ThemeData.localize(light, MaterialTextGeometry.tall))),
	);

	// Different base theme, different output.
	expect(
	ThemeData.localize(light, MaterialTextGeometry.englishLike),
	isNot(same(ThemeData.localize(dark, MaterialTextGeometry.englishLike))),
	);
	});

	testWidgets('PopupMenu inherits shadowed app theme', (WidgetTester tester) async {
	// Regression test for https://github.com/flutter/flutter/issues/5572
	final Key popupMenuButtonKey = UniqueKey();
	await tester.pumpWidget(
	MaterialApp(
	theme: ThemeData(brightness: Brightness.dark),
	home: Theme(
	data: ThemeData(brightness: Brightness.light),
	child: Scaffold(
	appBar: AppBar(
	actions: <Widget>[
	PopupMenuButton<String>(
	key: popupMenuButtonKey,
	itemBuilder: (BuildContext context) {
	return <PopupMenuItem<String>>[
	const PopupMenuItem<String>(child: Text('menuItem'))
	];
	}
	),
	]
	)
	)
	)
	)
	);

	await tester.tap(find.byKey(popupMenuButtonKey));
	await tester.pump(const Duration(seconds: 1));

	expect(Theme.of(tester.element(find.text('menuItem'))).brightness, equals(Brightness.light));
	});

	testWidgets('DropdownMenu inherits shadowed app theme', (WidgetTester tester) async {
	final Key dropdownMenuButtonKey = UniqueKey();
	await tester.pumpWidget(
	MaterialApp(
	theme: ThemeData(brightness: Brightness.dark),
	home: Theme(
	data: ThemeData(brightness: Brightness.light),
	child: Scaffold(
	appBar: AppBar(
	actions: <Widget>[
	DropdownButton<String>(
	key: dropdownMenuButtonKey,
	onChanged: (String newValue) { },
	value: 'menuItem',
	items: const <DropdownMenuItem<String>>[
	DropdownMenuItem<String>(
	value: 'menuItem',
	child: Text('menuItem'),
	),
	],
	)
	]
	)
	)
	)
	)
	);

	await tester.tap(find.byKey(dropdownMenuButtonKey));
	await tester.pump(const Duration(seconds: 1));

	for (Element item in tester.elementList(find.text('menuItem')))
	expect(Theme.of(item).brightness, equals(Brightness.light));
	});

	testWidgets('ModalBottomSheet inherits shadowed app theme', (WidgetTester tester) async {
	await tester.pumpWidget(
	MaterialApp(
	theme: ThemeData(brightness: Brightness.dark),
	home: Theme(
	data: ThemeData(brightness: Brightness.light),
	child: Scaffold(
	body: Center(
	child: Builder(
	builder: (BuildContext context) {
	return RaisedButton(
	onPressed: () {
	showModalBottomSheet<void>(
	context: context,
	builder: (BuildContext context) => const Text('bottomSheet'),
	);
	},
	child: const Text('SHOW'),
	);
	}
	)
	)
	)
	)
	)
	);

	await tester.tap(find.text('SHOW'));
	await tester.pump(const Duration(seconds: 1));
	expect(Theme.of(tester.element(find.text('bottomSheet'))).brightness, equals(Brightness.light));

	await tester.tap(find.text('bottomSheet')); // dismiss the bottom sheet
	await tester.pump(const Duration(seconds: 1));
	});

	testWidgets('Dialog inherits shadowed app theme', (WidgetTester tester) async {
	final GlobalKey<ScaffoldState> scaffoldKey = GlobalKey<ScaffoldState>();
	await tester.pumpWidget(
	MaterialApp(
	theme: ThemeData(brightness: Brightness.dark),
	home: Theme(
	data: ThemeData(brightness: Brightness.light),
	child: Scaffold(
	key: scaffoldKey,
	body: Center(
	child: Builder(
	builder: (BuildContext context) {
	return RaisedButton(
	onPressed: () {
	showDialog<void>(
	context: context,
	builder: (BuildContext context) => const Text('dialog'),
	);
	},
	child: const Text('SHOW'),
	);
	}
	)
	)
	)
	)
	)
	);

	await tester.tap(find.text('SHOW'));
	await tester.pump(const Duration(seconds: 1));
	expect(Theme.of(tester.element(find.text('dialog'))).brightness, equals(Brightness.light));
	});

	testWidgets("Scaffold inherits theme's scaffoldBackgroundColor", (WidgetTester tester) async {
	const Color green = Color(0xFF00FF00);

	await tester.pumpWidget(
	MaterialApp(
	theme: ThemeData(scaffoldBackgroundColor: green),
	home: Scaffold(
	body: Center(
	child: Builder(
	builder: (BuildContext context) {
	return GestureDetector(
	onTap: () {
	showDialog<void>(
	context: context,
	builder: (BuildContext context) {
	return const Scaffold(
	body: SizedBox(
	width: 200.0,
	height: 200.0,
	),
	);
	},
	);
	},
	child: const Text('SHOW'),
	);
	},
	),
	),
	),
	)
	);

	await tester.tap(find.text('SHOW'));
	await tester.pump(const Duration(seconds: 1));

	final List<Material> materials = tester.widgetList<Material>(find.byType(Material)).toList();
	expect(materials.length, equals(2));
	expect(materials[0].color, green); // app scaffold
	expect(materials[1].color, green); // dialog scaffold
	});

	testWidgets('IconThemes are applied', (WidgetTester tester) async {
	await tester.pumpWidget(
	MaterialApp(
	theme: ThemeData(iconTheme: const IconThemeData(color: Colors.green, size: 10.0)),
	home: const Icon(Icons.computer),
	)
	);

	RenderParagraph glyphText = tester.renderObject(find.byType(RichText));

	expect(glyphText.text.style.color, Colors.green);
	expect(glyphText.text.style.fontSize, 10.0);

	await tester.pumpWidget(
	MaterialApp(
	theme: ThemeData(iconTheme: const IconThemeData(color: Colors.orange, size: 20.0)),
	home: const Icon(Icons.computer),
	),
	);
	await tester.pump(const Duration(milliseconds: 100)); // Halfway through the theme transition

	glyphText = tester.renderObject(find.byType(RichText));

	expect(glyphText.text.style.color, Color.lerp(Colors.green, Colors.orange, 0.5));
	expect(glyphText.text.style.fontSize, 15.0);

	await tester.pump(const Duration(milliseconds: 100)); // Finish the transition
	glyphText = tester.renderObject(find.byType(RichText));

	expect(glyphText.text.style.color, Colors.orange);
	expect(glyphText.text.style.fontSize, 20.0);
	});

	testWidgets(
	'Same ThemeData reapplied does not trigger descendants rebuilds',
	(WidgetTester tester) async {
	testBuildCalled = 0;
	ThemeData themeData = ThemeData(primaryColor: const Color(0xFF000000));

	Widget buildTheme() {
	return Theme(
	data: themeData,
	child: const Test(),
	);
	}

	await tester.pumpWidget(buildTheme());
	expect(testBuildCalled, 1);

	// Pump the same widgets again.
	await tester.pumpWidget(buildTheme());
	// No repeated build calls to the child since it's the same theme data.
	expect(testBuildCalled, 1);

	// New instance of theme data but still the same content.
	themeData = ThemeData(primaryColor: const Color(0xFF000000));
	await tester.pumpWidget(buildTheme());
	// Still no repeated calls.
	expect(testBuildCalled, 1);

	// Different now.
	themeData = ThemeData(primaryColor: const Color(0xFF222222));
	await tester.pumpWidget(buildTheme());
	// Should call build again.
	expect(testBuildCalled, 2);
	},
	);

	testWidgets('Text geometry set in Theme has higher precedence than that of Localizations', (WidgetTester tester) async {
	const double _kMagicFontSize = 4321.0;
	final ThemeData fallback = ThemeData.fallback();
	final ThemeData customTheme = fallback.copyWith(
	primaryTextTheme: fallback.primaryTextTheme.copyWith(
	body1: fallback.primaryTextTheme.body1.copyWith(
	fontSize: _kMagicFontSize,
	)
	),
	);
	expect(customTheme.primaryTextTheme.body1.fontSize, _kMagicFontSize);

	double actualFontSize;
	await tester.pumpWidget(Directionality(
	textDirection: TextDirection.ltr,
	child: Theme(
	data: customTheme,
	child: Builder(builder: (BuildContext context) {
	final ThemeData theme = Theme.of(context);
	actualFontSize = theme.primaryTextTheme.body1.fontSize;
	return Text(
	'A',
	style: theme.primaryTextTheme.body1,
	);
	}),
	),
	));

	expect(actualFontSize, _kMagicFontSize);
	});

	testWidgets('Default Theme provides all basic TextStyle properties', (WidgetTester tester) async {
	ThemeData theme;
	await tester.pumpWidget(Directionality(
	textDirection: TextDirection.ltr,
	child: Builder(
	builder: (BuildContext context) {
	theme = Theme.of(context);
	return const Text('A');
	},
	),
	));

	List<TextStyle> extractStyles(TextTheme textTheme) {
	return <TextStyle>[
	textTheme.display4,
	textTheme.display3,
	textTheme.display2,
	textTheme.display1,
	textTheme.headline,
	textTheme.title,
	textTheme.subhead,
	textTheme.body2,
	textTheme.body1,
	textTheme.caption,
	textTheme.button,
	];
	}

	for (TextTheme textTheme in <TextTheme>[theme.textTheme, theme.primaryTextTheme, theme.accentTextTheme]) {
	for (TextStyle style in extractStyles(textTheme).map((TextStyle style) => _TextStyleProxy(style))) {
	expect(style.inherit, false);
	expect(style.color, isNotNull);
	expect(style.fontFamily, isNotNull);
	expect(style.fontSize, isNotNull);
	expect(style.fontWeight, isNotNull);
	expect(style.fontStyle, null);
	expect(style.letterSpacing, null);
	expect(style.wordSpacing, null);
	expect(style.textBaseline, isNotNull);
	expect(style.height, null);
	expect(style.decoration, TextDecoration.none);
	expect(style.decorationColor, null);
	expect(style.decorationStyle, null);
	expect(style.debugLabel, isNotNull);
	expect(style.locale, null);
	expect(style.background, null);
	}
	}

	expect(theme.textTheme.display4.debugLabel, '(englishLike display4).merge(blackMountainView display4)');
	});
	}

	int testBuildCalled;
	class Test extends StatefulWidget {
	const Test();

	@override
	_TestState createState() => _TestState();
	}

	class _TestState extends State<Test> {
	@override
	Widget build(BuildContext context) {
	testBuildCalled += 1;
	return Container(
	decoration: BoxDecoration(
	color: Theme.of(context).primaryColor,
	),
	);
	}
	}

	/// This class exists only to make sure that we test all the properties of the
	/// [TextStyle] class. If a property is added/removed/renamed, the analyzer will
	/// complain that this class has incorrect overrides.
	class _TextStyleProxy implements TextStyle {
	_TextStyleProxy(this._delegate);

	final TextStyle _delegate;

	// Do make sure that all the properties correctly forward to the _delegate.
	@override Color get color => _delegate.color;
	@override String get debugLabel => _delegate.debugLabel;
	@override TextDecoration get decoration => _delegate.decoration;
	@override Color get decorationColor => _delegate.decorationColor;
	@override TextDecorationStyle get decorationStyle => _delegate.decorationStyle;
	@override String get fontFamily => _delegate.fontFamily;
	@override double get fontSize => _delegate.fontSize;
	@override FontStyle get fontStyle => _delegate.fontStyle;
	@override FontWeight get fontWeight => _delegate.fontWeight;
	@override double get height => _delegate.height;
	@override Locale get locale => _delegate.locale;
	@override ui.Paint get foreground => _delegate.foreground;
	@override ui.Paint get background => _delegate.background;
	@override bool get inherit => _delegate.inherit;
	@override double get letterSpacing => _delegate.letterSpacing;
	@override TextBaseline get textBaseline => _delegate.textBaseline;
	@override double get wordSpacing => _delegate.wordSpacing;

	@override
	String toString({DiagnosticLevel minLevel = DiagnosticLevel.debug}) =>
	super.toString();

	@override
	DiagnosticsNode toDiagnosticsNode({String name, DiagnosticsTreeStyle style}) {
	throw UnimplementedError();
	}

	@override
	String toStringShort() {
	throw UnimplementedError();
	}

	@override
	TextStyle apply({Color color, TextDecoration decoration, Color decorationColor, TextDecorationStyle decorationStyle, String fontFamily, double fontSizeFactor = 1.0, double fontSizeDelta = 0.0, int fontWeightDelta = 0, double letterSpacingFactor = 1.0, double letterSpacingDelta = 0.0, double wordSpacingFactor = 1.0, double wordSpacingDelta = 0.0, double heightFactor = 1.0, double heightDelta = 0.0}) {
	throw UnimplementedError();
	}

	@override
	RenderComparison compareTo(TextStyle other) {
	throw UnimplementedError();
	}

	@override
	TextStyle copyWith({Color color, String fontFamily, double fontSize, FontWeight fontWeight, FontStyle fontStyle, double letterSpacing, double wordSpacing, TextBaseline textBaseline, double height, Locale locale, ui.Paint foreground, ui.Paint background, TextDecoration decoration, Color decorationColor, TextDecorationStyle decorationStyle, String debugLabel}) {
	throw UnimplementedError();
	}

	@override
	void debugFillProperties(DiagnosticPropertiesBuilder properties, {String prefix = ''}) {
	throw UnimplementedError();
	}

	@override
	ui.ParagraphStyle getParagraphStyle({TextAlign textAlign, TextDirection textDirection, double textScaleFactor = 1.0, String ellipsis, int maxLines, Locale locale}) {
	throw UnimplementedError();
	}

	@override
	ui.TextStyle getTextStyle({double textScaleFactor = 1.0}) {
	throw UnimplementedError();
	}

	@override
	TextStyle merge(TextStyle other) {
	throw UnimplementedError();
	}
	}