Add missing properties to TextStyle.apply (#54305)

packages/flutter/lib/src/painting/text_style.dart

@@ -794,12 +794,17 @@ class TextStyle with Diagnosticable {
     double fontSizeFactor = 1.0,
     double fontSizeDelta = 0.0,
     int fontWeightDelta = 0,
+    FontStyle fontStyle,
     double letterSpacingFactor = 1.0,
     double letterSpacingDelta = 0.0,
     double wordSpacingFactor = 1.0,
     double wordSpacingDelta = 0.0,
     double heightFactor = 1.0,
     double heightDelta = 0.0,
+    TextBaseline textBaseline,
+    Locale locale,
+    List<ui.Shadow> shadows,
+    List<ui.FontFeature> fontFeatures,
   }) {
     assert(fontSizeFactor != null);
     assert(fontSizeDelta != null);
@@ -834,16 +839,16 @@ class TextStyle with Diagnosticable {
       fontFamilyFallback: fontFamilyFallback ?? this.fontFamilyFallback,
       fontSize: fontSize == null ? null : fontSize * fontSizeFactor + fontSizeDelta,
       fontWeight: fontWeight == null ? null : FontWeight.values[(fontWeight.index + fontWeightDelta).clamp(0, FontWeight.values.length - 1) as int],
-      fontStyle: fontStyle,
+      fontStyle: fontStyle ?? this.fontStyle,
       letterSpacing: letterSpacing == null ? null : letterSpacing * letterSpacingFactor + letterSpacingDelta,
       wordSpacing: wordSpacing == null ? null : wordSpacing * wordSpacingFactor + wordSpacingDelta,
       textBaseline: textBaseline,
       height: height == null ? null : height * heightFactor + heightDelta,
-      locale: locale,
+      locale: locale ?? this.locale,
       foreground: foreground,
       background: background,
-      shadows: shadows,
+      shadows: shadows ?? this.shadows,
-      fontFeatures: fontFeatures,
+      fontFeatures: fontFeatures ?? this.fontFeatures,
       decoration: decoration ?? this.decoration,
       decorationColor: decorationColor ?? this.decorationColor,
       decorationStyle: decorationStyle ?? this.decorationStyle,

packages/flutter/test/material/theme_test.dart

@@ -774,12 +774,17 @@ class _TextStyleProxy implements TextStyle {
     double fontSizeFactor = 1.0,
     double fontSizeDelta = 0.0,
     int fontWeightDelta = 0,
+    FontStyle fontStyle,
     double letterSpacingFactor = 1.0,
     double letterSpacingDelta = 0.0,
     double wordSpacingFactor = 1.0,
     double wordSpacingDelta = 0.0,
     double heightFactor = 1.0,
     double heightDelta = 0.0,
+    TextBaseline textBaseline,
+    Locale locale,
+    List<ui.Shadow> shadows,
+    List<ui.FontFeature> fontFeatures,
   }) {
     throw UnimplementedError();
   }

packages/flutter/test/painting/text_style_test.dart

@@ -233,6 +233,11 @@ void main() {
 
     final ui.TextStyle uis1 = s2.getTextStyle();
     expect(uis1.toString(), 'TextStyle(color: unspecified, decoration: unspecified, decorationColor: unspecified, decorationStyle: unspecified, decorationThickness: unspecified, fontWeight: unspecified, fontStyle: unspecified, textBaseline: unspecified, fontFamily: foo, fontFamilyFallback: [Roboto, test], fontSize: unspecified, letterSpacing: unspecified, wordSpacing: unspecified, height: unspecified, locale: unspecified, background: unspecified, foreground: unspecified, shadows: unspecified, fontFeatures: unspecified)');
+
+    expect(s2.apply().fontFamily, 'foo');
+    expect(s2.apply().fontFamilyFallback, const <String>['Roboto', 'test']);
+    expect(s2.apply(fontFamily: 'bar').fontFamily, 'bar');
+    expect(s2.apply(fontFamilyFallback: const <String>['Banana']).fontFamilyFallback, const <String>['Banana']);
   }, skip: isBrowser);
 
   test('TextStyle.debugLabel', () {
@@ -367,4 +372,16 @@ void main() {
 
     expect(paragraphStyle0 == paragraphStyle1, true);
   });
+
+  test('TextStyle apply', () {
+    const TextStyle style = TextStyle(fontSize: 10);
+    expect(style.apply().shadows, isNull);
+    expect(style.apply(shadows: const <ui.Shadow>[ui.Shadow(blurRadius: 2.0)]).shadows, const <ui.Shadow>[ui.Shadow(blurRadius: 2.0)]);
+    expect(style.apply().fontStyle, isNull);
+    expect(style.apply(fontStyle: FontStyle.italic).fontStyle, FontStyle.italic);
+    expect(style.apply().locale, isNull);
+    expect(style.apply(locale: const Locale.fromSubtags(languageCode: 'es')).locale, const Locale.fromSubtags(languageCode: 'es'));
+    expect(style.apply().fontFeatures, isNull);
+    expect(style.apply(fontFeatures: const <ui.FontFeature>[ui.FontFeature.enable('test')]).fontFeatures, const <ui.FontFeature>[ui.FontFeature.enable('test')]);
+  });
 }