Moshe Dicker 4d50910b8a
Adds support for applying delta/factor transformations for TextTheme height, letter and word spacing (#158103)
Closes https://github.com/flutter/flutter/issues/158102


The text theme has the `apply` method which does bulk operations on
multiple text styles. It supports delta/factor ajustements for font
size. This is very helpful for changing all the font sizes at once using
a ratio or a simple delta.
This PR add support for height, letter spacing and and word spacing too.

### Why is this so useful?

Adjusting these in bulk is really helpful for using custom fonts. The
Material font comes which its own default text styes and they're usually
great. But many times they need to be nudged tighter.

### Doc Comment

`apply` has no doc comments for `fontSizeFactor`/`fontSizeDelta` so i
did not add any for the new `letterSpacingFactor`,
`letterSpacingDelta`... either. If we want to add it, I'll do it.

### Tests
Done!

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [ ] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

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---------

Co-authored-by: Tong Mu <dkwingsmt@users.noreply.github.com>
2025-02-21 18:40:05 +00:00

447 lines
20 KiB
Dart

// Copyright 2014 The Flutter 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 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
void main() {
test('TextTheme copyWith apply, merge basics with const TextTheme()', () {
expect(const TextTheme(), equals(const TextTheme().copyWith()));
expect(const TextTheme(), equals(const TextTheme().apply()));
expect(const TextTheme(), equals(const TextTheme().merge(null)));
expect(const TextTheme().hashCode, equals(const TextTheme().copyWith().hashCode));
expect(const TextTheme(), equals(const TextTheme().copyWith()));
});
test('TextTheme lerp special cases', () {
expect(TextTheme.lerp(null, null, 0), const TextTheme());
const TextTheme theme = TextTheme();
expect(identical(TextTheme.lerp(theme, theme, 0.5), theme), true);
});
test('TextTheme copyWith apply, merge basics with Typography.black', () {
final Typography typography = Typography.material2018();
expect(typography.black, equals(typography.black.copyWith()));
expect(typography.black, equals(typography.black.apply()));
expect(typography.black, equals(typography.black.merge(null)));
expect(typography.black, equals(const TextTheme().merge(typography.black)));
expect(typography.black, equals(typography.black.merge(typography.black)));
expect(typography.white, equals(typography.black.merge(typography.white)));
expect(typography.black.hashCode, equals(typography.black.copyWith().hashCode));
expect(typography.black, isNot(equals(typography.white)));
});
test('TextTheme copyWith', () {
final Typography typography = Typography.material2018();
final TextTheme whiteCopy = typography.black.copyWith(
displayLarge: typography.white.displayLarge,
displayMedium: typography.white.displayMedium,
displaySmall: typography.white.displaySmall,
headlineLarge: typography.white.headlineLarge,
headlineMedium: typography.white.headlineMedium,
headlineSmall: typography.white.headlineSmall,
titleLarge: typography.white.titleLarge,
titleMedium: typography.white.titleMedium,
titleSmall: typography.white.titleSmall,
bodyLarge: typography.white.bodyLarge,
bodyMedium: typography.white.bodyMedium,
bodySmall: typography.white.bodySmall,
labelLarge: typography.white.labelLarge,
labelMedium: typography.white.labelMedium,
labelSmall: typography.white.labelSmall,
);
expect(typography.white, equals(whiteCopy));
});
test('TextTheme merges properly in the presence of null fields.', () {
const TextTheme partialTheme = TextTheme(titleLarge: TextStyle(color: Color(0xcafefeed)));
final TextTheme fullTheme = ThemeData.fallback().textTheme.merge(partialTheme);
expect(fullTheme.titleLarge!.color, equals(partialTheme.titleLarge!.color));
const TextTheme onlyHeadlineSmallAndTitleLarge = TextTheme(
headlineSmall: TextStyle(color: Color(0xcafefeed)),
titleLarge: TextStyle(color: Color(0xbeefcafe)),
);
const TextTheme onlyBodyMediumAndTitleLarge = TextTheme(
bodyMedium: TextStyle(color: Color(0xfeedfeed)),
titleLarge: TextStyle(color: Color(0xdeadcafe)),
);
TextTheme merged = onlyHeadlineSmallAndTitleLarge.merge(onlyBodyMediumAndTitleLarge);
expect(merged.bodyLarge, isNull);
expect(merged.bodyMedium!.color, equals(onlyBodyMediumAndTitleLarge.bodyMedium!.color));
expect(
merged.headlineSmall!.color,
equals(onlyHeadlineSmallAndTitleLarge.headlineSmall!.color),
);
expect(merged.titleLarge!.color, equals(onlyBodyMediumAndTitleLarge.titleLarge!.color));
merged = onlyHeadlineSmallAndTitleLarge.merge(null);
expect(merged, equals(onlyHeadlineSmallAndTitleLarge));
});
test('TextTheme apply', () {
// The `displayColor` is applied to [displayLarge], [displayMedium],
// [displaySmall], [headlineLarge], [headlineMedium], and [bodySmall]. The
// `bodyColor` is applied to the remaining text styles.
const Color displayColor = Color(0x00000001);
const Color bodyColor = Color(0x00000002);
const String fontFamily = 'fontFamily';
const List<String> fontFamilyFallback = <String>['font', 'family', 'fallback'];
const Color decorationColor = Color(0x00000003);
const TextDecorationStyle decorationStyle = TextDecorationStyle.dashed;
final TextDecoration decoration = TextDecoration.combine(<TextDecoration>[
TextDecoration.underline,
TextDecoration.lineThrough,
]);
final Typography typography = Typography.material2018();
final TextTheme theme = typography.black.apply(
fontFamily: fontFamily,
fontFamilyFallback: fontFamilyFallback,
displayColor: displayColor,
bodyColor: bodyColor,
decoration: decoration,
decorationColor: decorationColor,
decorationStyle: decorationStyle,
);
expect(theme.displayLarge!.color, displayColor);
expect(theme.displayMedium!.color, displayColor);
expect(theme.displaySmall!.color, displayColor);
expect(theme.headlineLarge!.color, displayColor);
expect(theme.headlineMedium!.color, displayColor);
expect(theme.headlineSmall!.color, bodyColor);
expect(theme.titleLarge!.color, bodyColor);
expect(theme.titleMedium!.color, bodyColor);
expect(theme.titleSmall!.color, bodyColor);
expect(theme.bodyLarge!.color, bodyColor);
expect(theme.bodyMedium!.color, bodyColor);
expect(theme.bodySmall!.color, displayColor);
expect(theme.labelLarge!.color, bodyColor);
expect(theme.labelMedium!.color, bodyColor);
expect(theme.labelSmall!.color, bodyColor);
final List<TextStyle> themeStyles = <TextStyle>[
theme.displayLarge!,
theme.displayMedium!,
theme.displaySmall!,
theme.headlineLarge!,
theme.headlineMedium!,
theme.headlineSmall!,
theme.titleLarge!,
theme.titleMedium!,
theme.titleSmall!,
theme.bodyLarge!,
theme.bodyMedium!,
theme.bodySmall!,
theme.labelLarge!,
theme.labelMedium!,
theme.labelSmall!,
];
expect(themeStyles.every((TextStyle style) => style.fontFamily == fontFamily), true);
expect(
themeStyles.every((TextStyle style) => style.fontFamilyFallback == fontFamilyFallback),
true,
);
expect(themeStyles.every((TextStyle style) => style.decorationColor == decorationColor), true);
expect(themeStyles.every((TextStyle style) => style.decorationStyle == decorationStyle), true);
expect(themeStyles.every((TextStyle style) => style.decoration == decoration), true);
});
test('TextTheme apply fontSizeFactor fontSizeDelta', () {
final Typography typography = Typography.material2018();
final TextTheme baseTheme = Typography.englishLike2018.merge(typography.black);
final TextTheme sizeTheme = baseTheme.apply(fontSizeFactor: 2.0, fontSizeDelta: 5.0);
expect(sizeTheme.displayLarge!.fontSize, baseTheme.displayLarge!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.displayMedium!.fontSize, baseTheme.displayMedium!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.displaySmall!.fontSize, baseTheme.displaySmall!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.headlineLarge!.fontSize, baseTheme.headlineLarge!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.headlineMedium!.fontSize, baseTheme.headlineMedium!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.headlineSmall!.fontSize, baseTheme.headlineSmall!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.titleLarge!.fontSize, baseTheme.titleLarge!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.titleMedium!.fontSize, baseTheme.titleMedium!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.titleSmall!.fontSize, baseTheme.titleSmall!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.bodyLarge!.fontSize, baseTheme.bodyLarge!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.bodyMedium!.fontSize, baseTheme.bodyMedium!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.bodySmall!.fontSize, baseTheme.bodySmall!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.labelLarge!.fontSize, baseTheme.labelLarge!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.labelMedium!.fontSize, baseTheme.labelMedium!.fontSize! * 2.0 + 5.0);
expect(sizeTheme.labelSmall!.fontSize, baseTheme.labelSmall!.fontSize! * 2.0 + 5.0);
});
test('TextTheme apply letterSpacingFactor letterSpacingDelta', () {
final Typography typography = Typography.material2018();
final TextTheme baseTheme = Typography.englishLike2018.merge(typography.black);
final TextTheme sizeTheme = baseTheme.apply(letterSpacingFactor: 2.0, letterSpacingDelta: 5.0);
expect(
sizeTheme.displayLarge!.letterSpacing,
baseTheme.displayLarge!.letterSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.displayMedium!.letterSpacing,
baseTheme.displayMedium!.letterSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.displaySmall!.letterSpacing,
baseTheme.displaySmall!.letterSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.headlineLarge!.letterSpacing,
baseTheme.headlineLarge!.letterSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.headlineMedium!.letterSpacing,
baseTheme.headlineMedium!.letterSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.headlineSmall!.letterSpacing,
baseTheme.headlineSmall!.letterSpacing! * 2.0 + 5.0,
);
expect(sizeTheme.titleLarge!.letterSpacing, baseTheme.titleLarge!.letterSpacing! * 2.0 + 5.0);
expect(sizeTheme.titleMedium!.letterSpacing, baseTheme.titleMedium!.letterSpacing! * 2.0 + 5.0);
expect(sizeTheme.titleSmall!.letterSpacing, baseTheme.titleSmall!.letterSpacing! * 2.0 + 5.0);
expect(sizeTheme.bodyLarge!.letterSpacing, baseTheme.bodyLarge!.letterSpacing! * 2.0 + 5.0);
expect(sizeTheme.bodyMedium!.letterSpacing, baseTheme.bodyMedium!.letterSpacing! * 2.0 + 5.0);
expect(sizeTheme.bodySmall!.letterSpacing, baseTheme.bodySmall!.letterSpacing! * 2.0 + 5.0);
expect(sizeTheme.labelLarge!.letterSpacing, baseTheme.labelLarge!.letterSpacing! * 2.0 + 5.0);
expect(sizeTheme.labelMedium!.letterSpacing, baseTheme.labelMedium!.letterSpacing! * 2.0 + 5.0);
expect(sizeTheme.labelSmall!.letterSpacing, baseTheme.labelSmall!.letterSpacing! * 2.0 + 5.0);
});
test('TextTheme apply wordSpacingFactor wordSpacingDelta', () {
final Typography typography = Typography.material2018();
final TextTheme baseTheme = Typography.englishLike2018.merge(typography.black);
final TextTheme baseThemeWithWordSpacing = baseTheme.copyWith(
displayLarge: baseTheme.displayLarge!.copyWith(wordSpacing: 1.0),
displayMedium: baseTheme.displayMedium!.copyWith(wordSpacing: 1.0),
displaySmall: baseTheme.displaySmall!.copyWith(wordSpacing: 1.0),
headlineLarge: baseTheme.headlineLarge!.copyWith(wordSpacing: 1.0),
headlineMedium: baseTheme.headlineMedium!.copyWith(wordSpacing: 1.0),
headlineSmall: baseTheme.headlineSmall!.copyWith(wordSpacing: 1.0),
titleLarge: baseTheme.titleLarge!.copyWith(wordSpacing: 1.0),
titleMedium: baseTheme.titleMedium!.copyWith(wordSpacing: 1.0),
titleSmall: baseTheme.titleSmall!.copyWith(wordSpacing: 1.0),
bodyLarge: baseTheme.bodyLarge!.copyWith(wordSpacing: 1.0),
bodyMedium: baseTheme.bodyMedium!.copyWith(wordSpacing: 1.0),
bodySmall: baseTheme.bodySmall!.copyWith(wordSpacing: 1.0),
labelLarge: baseTheme.labelLarge!.copyWith(wordSpacing: 1.0),
labelMedium: baseTheme.labelMedium!.copyWith(wordSpacing: 1.0),
labelSmall: baseTheme.labelSmall!.copyWith(wordSpacing: 1.0),
);
final TextTheme sizeTheme = baseThemeWithWordSpacing.apply(
wordSpacingFactor: 2.0,
wordSpacingDelta: 5.0,
);
expect(
sizeTheme.displayLarge!.wordSpacing,
baseThemeWithWordSpacing.displayLarge!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.displayMedium!.wordSpacing,
baseThemeWithWordSpacing.displayMedium!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.displaySmall!.wordSpacing,
baseThemeWithWordSpacing.displaySmall!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.headlineLarge!.wordSpacing,
baseThemeWithWordSpacing.headlineLarge!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.headlineMedium!.wordSpacing,
baseThemeWithWordSpacing.headlineMedium!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.headlineSmall!.wordSpacing,
baseThemeWithWordSpacing.headlineSmall!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.titleLarge!.wordSpacing,
baseThemeWithWordSpacing.titleLarge!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.titleMedium!.wordSpacing,
baseThemeWithWordSpacing.titleMedium!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.titleSmall!.wordSpacing,
baseThemeWithWordSpacing.titleSmall!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.bodyLarge!.wordSpacing,
baseThemeWithWordSpacing.bodyLarge!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.bodyMedium!.wordSpacing,
baseThemeWithWordSpacing.bodyMedium!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.bodySmall!.wordSpacing,
baseThemeWithWordSpacing.bodySmall!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.labelLarge!.wordSpacing,
baseThemeWithWordSpacing.labelLarge!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.labelMedium!.wordSpacing,
baseThemeWithWordSpacing.labelMedium!.wordSpacing! * 2.0 + 5.0,
);
expect(
sizeTheme.labelSmall!.wordSpacing,
baseThemeWithWordSpacing.labelSmall!.wordSpacing! * 2.0 + 5.0,
);
});
test('TextTheme apply heightFactor heightDelta', () {
final Typography typography = Typography.material2021();
final TextTheme baseTheme = Typography.englishLike2021.merge(typography.black);
final TextTheme sizeTheme = baseTheme.apply(heightFactor: 2.0, heightDelta: 5.0);
expect(sizeTheme.displayLarge!.height, baseTheme.displayLarge!.height! * 2.0 + 5.0);
expect(sizeTheme.displayMedium!.height, baseTheme.displayMedium!.height! * 2.0 + 5.0);
expect(sizeTheme.displaySmall!.height, baseTheme.displaySmall!.height! * 2.0 + 5.0);
expect(sizeTheme.headlineLarge!.height, baseTheme.headlineLarge!.height! * 2.0 + 5.0);
expect(sizeTheme.headlineMedium!.height, baseTheme.headlineMedium!.height! * 2.0 + 5.0);
expect(sizeTheme.headlineSmall!.height, baseTheme.headlineSmall!.height! * 2.0 + 5.0);
expect(sizeTheme.titleLarge!.height, baseTheme.titleLarge!.height! * 2.0 + 5.0);
expect(sizeTheme.titleMedium!.height, baseTheme.titleMedium!.height! * 2.0 + 5.0);
expect(sizeTheme.titleSmall!.height, baseTheme.titleSmall!.height! * 2.0 + 5.0);
expect(sizeTheme.bodyLarge!.height, baseTheme.bodyLarge!.height! * 2.0 + 5.0);
expect(sizeTheme.bodyMedium!.height, baseTheme.bodyMedium!.height! * 2.0 + 5.0);
expect(sizeTheme.bodySmall!.height, baseTheme.bodySmall!.height! * 2.0 + 5.0);
expect(sizeTheme.labelLarge!.height, baseTheme.labelLarge!.height! * 2.0 + 5.0);
expect(sizeTheme.labelMedium!.height, baseTheme.labelMedium!.height! * 2.0 + 5.0);
expect(sizeTheme.labelSmall!.height, baseTheme.labelSmall!.height! * 2.0 + 5.0);
});
test('TextTheme lerp with second parameter null', () {
final TextTheme theme = Typography.material2018().black;
final TextTheme lerped = TextTheme.lerp(theme, null, 0.25);
expect(lerped.displayLarge, TextStyle.lerp(theme.displayLarge, null, 0.25));
expect(lerped.displayMedium, TextStyle.lerp(theme.displayMedium, null, 0.25));
expect(lerped.displaySmall, TextStyle.lerp(theme.displaySmall, null, 0.25));
expect(lerped.headlineLarge, TextStyle.lerp(theme.headlineLarge, null, 0.25));
expect(lerped.headlineMedium, TextStyle.lerp(theme.headlineMedium, null, 0.25));
expect(lerped.headlineSmall, TextStyle.lerp(theme.headlineSmall, null, 0.25));
expect(lerped.titleLarge, TextStyle.lerp(theme.titleLarge, null, 0.25));
expect(lerped.titleMedium, TextStyle.lerp(theme.titleMedium, null, 0.25));
expect(lerped.titleSmall, TextStyle.lerp(theme.titleSmall, null, 0.25));
expect(lerped.bodyLarge, TextStyle.lerp(theme.bodyLarge, null, 0.25));
expect(lerped.bodyMedium, TextStyle.lerp(theme.bodyMedium, null, 0.25));
expect(lerped.bodySmall, TextStyle.lerp(theme.bodySmall, null, 0.25));
expect(lerped.labelLarge, TextStyle.lerp(theme.labelLarge, null, 0.25));
expect(lerped.labelMedium, TextStyle.lerp(theme.labelMedium, null, 0.25));
expect(lerped.labelSmall, TextStyle.lerp(theme.labelSmall, null, 0.25));
});
test('TextTheme lerp with first parameter null', () {
final TextTheme theme = Typography.material2018().black;
final TextTheme lerped = TextTheme.lerp(null, theme, 0.25);
expect(lerped.displayLarge, TextStyle.lerp(null, theme.displayLarge, 0.25));
expect(lerped.displayMedium, TextStyle.lerp(null, theme.displayMedium, 0.25));
expect(lerped.displaySmall, TextStyle.lerp(null, theme.displaySmall, 0.25));
expect(lerped.headlineLarge, TextStyle.lerp(null, theme.headlineLarge, 0.25));
expect(lerped.headlineMedium, TextStyle.lerp(null, theme.headlineMedium, 0.25));
expect(lerped.headlineSmall, TextStyle.lerp(null, theme.headlineSmall, 0.25));
expect(lerped.titleLarge, TextStyle.lerp(null, theme.titleLarge, 0.25));
expect(lerped.titleMedium, TextStyle.lerp(null, theme.titleMedium, 0.25));
expect(lerped.titleSmall, TextStyle.lerp(null, theme.titleSmall, 0.25));
expect(lerped.bodyLarge, TextStyle.lerp(null, theme.bodyLarge, 0.25));
expect(lerped.bodyMedium, TextStyle.lerp(null, theme.bodyMedium, 0.25));
expect(lerped.bodySmall, TextStyle.lerp(null, theme.bodySmall, 0.25));
expect(lerped.labelLarge, TextStyle.lerp(null, theme.labelLarge, 0.25));
expect(lerped.labelMedium, TextStyle.lerp(null, theme.labelMedium, 0.25));
expect(lerped.labelSmall, TextStyle.lerp(null, theme.labelSmall, 0.25));
});
test('TextTheme lerp with null parameters', () {
final TextTheme lerped = TextTheme.lerp(null, null, 0.25);
expect(lerped.displayLarge, null);
expect(lerped.displayMedium, null);
expect(lerped.displaySmall, null);
expect(lerped.headlineLarge, null);
expect(lerped.headlineMedium, null);
expect(lerped.headlineSmall, null);
expect(lerped.titleLarge, null);
expect(lerped.titleMedium, null);
expect(lerped.titleSmall, null);
expect(lerped.bodyLarge, null);
expect(lerped.bodyMedium, null);
expect(lerped.bodySmall, null);
expect(lerped.labelLarge, null);
expect(lerped.labelMedium, null);
expect(lerped.labelSmall, null);
});
test('VisualDensity.lerp', () {
const VisualDensity a = VisualDensity(horizontal: 1.0, vertical: .5);
const VisualDensity b = VisualDensity(horizontal: 2.0, vertical: 1.0);
final VisualDensity noLerp = VisualDensity.lerp(a, b, 0.0);
expect(noLerp.horizontal, 1.0);
expect(noLerp.vertical, .5);
final VisualDensity quarterLerp = VisualDensity.lerp(a, b, .25);
expect(quarterLerp.horizontal, 1.25);
expect(quarterLerp.vertical, .625);
final VisualDensity fullLerp = VisualDensity.lerp(a, b, 1.0);
expect(fullLerp.horizontal, 2.0);
expect(fullLerp.vertical, 1.0);
});
testWidgets('TextTheme.of(context) is equivalent to Theme.of(context).textTheme', (
WidgetTester tester,
) async {
const Key sizedBoxKey = Key('sizedBox');
await tester.pumpWidget(
MaterialApp(
theme: ThemeData(
textTheme: const TextTheme(displayLarge: TextStyle(color: Colors.blue, fontSize: 30.0)),
),
home: const SizedBox(key: sizedBoxKey),
),
);
final BuildContext context = tester.element(find.byKey(sizedBoxKey));
final ThemeData themeData = Theme.of(context);
final TextTheme expectedTextTheme = themeData.textTheme;
final TextTheme actualTextTheme = TextTheme.of(context);
expect(actualTextTheme, equals(expectedTextTheme));
});
testWidgets('TextTheme.primaryOf(context) is equivalent to Theme.of(context).primaryTextTheme', (
WidgetTester tester,
) async {
const Key sizedBoxKey = Key('sizedBox');
await tester.pumpWidget(
MaterialApp(
theme: ThemeData(
primaryTextTheme: const TextTheme(
displayLarge: TextStyle(backgroundColor: Colors.green, fontStyle: FontStyle.italic),
),
),
home: const SizedBox(key: sizedBoxKey),
),
);
final BuildContext context = tester.element(find.byKey(sizedBoxKey));
final ThemeData themeData = Theme.of(context);
final TextTheme expectedTextTheme = themeData.primaryTextTheme;
final TextTheme actualTextTheme = TextTheme.primaryOf(context);
expect(actualTextTheme, equals(expectedTextTheme));
});
}