[web] Remove EngineParagraph and ParagraphGeometricStyle (flutter#30766)

Author: mdebbar

lib/web_ui/lib/src/engine/engine_canvas.dart

@@ -12,7 +12,7 @@ import 'package:ui/ui.dart' as ui;
 
 import 'html/painting.dart';
 import 'html/render_vertices.dart';
-import 'text/paragraph.dart';
+import 'text/canvas_paragraph.dart';
 import 'util.dart';
 import 'vector_math.dart';
 
@@ -76,7 +76,7 @@ abstract class EngineCanvas {
   void drawImageRect(
       ui.Image image, ui.Rect src, ui.Rect dst, SurfacePaintData paint);
 
-  void drawParagraph(EngineParagraph paragraph, ui.Offset offset);
+  void drawParagraph(CanvasParagraph paragraph, ui.Offset offset);
 
   void drawVertices(
       SurfaceVertices vertices, ui.BlendMode blendMode, SurfacePaintData paint);
@@ -258,7 +258,7 @@ mixin SaveStackTracking on EngineCanvas {
 }
 
 html.Element drawParagraphElement(
-  EngineParagraph paragraph,
+  CanvasParagraph paragraph,
   ui.Offset offset, {
   Matrix4? transform,
 }) {

lib/web_ui/lib/src/engine/html/bitmap_canvas.dart

@@ -16,7 +16,7 @@ import '../engine_canvas.dart';
 import '../frame_reference.dart';
 import '../html_image_codec.dart';
 import '../platform_dispatcher.dart';
-import '../text/paragraph.dart';
+import '../text/canvas_paragraph.dart';
 import '../util.dart';
 import '../vector_math.dart';
 import '../window.dart';
@@ -936,7 +936,7 @@ class BitmapCanvas extends EngineCanvas {
   }
 
   @override
-  void drawParagraph(EngineParagraph paragraph, ui.Offset offset) {
+  void drawParagraph(CanvasParagraph paragraph, ui.Offset offset) {
     assert(paragraph.isLaidOut);
 
     /// - paragraph.drawOnCanvas checks that the text styling doesn't include

lib/web_ui/lib/src/engine/html/dom_canvas.dart

@@ -12,7 +12,7 @@ import 'package:ui/ui.dart' as ui;
 import '../browser_detection.dart';
 import '../engine_canvas.dart';
 import '../html_image_codec.dart';
-import '../text/paragraph.dart';
+import '../text/canvas_paragraph.dart';
 import '../util.dart';
 import '../vector_math.dart';
 import 'painting.dart';
@@ -127,7 +127,7 @@ class DomCanvas extends EngineCanvas with SaveElementStackTracking {
   @override
   void drawParagraph(ui.Paragraph paragraph, ui.Offset offset) {
     final html.Element paragraphElement = drawParagraphElement(
-        paragraph as EngineParagraph, offset,
+        paragraph as CanvasParagraph, offset,
         transform: currentTransform);
     currentElement.append(paragraphElement);
   }

lib/web_ui/lib/src/engine/html/recording_canvas.dart

@@ -11,7 +11,7 @@ import '../engine_canvas.dart';
 import '../picture.dart';
 import '../rrect_renderer.dart';
 import '../shadow.dart';
-import '../text/paragraph.dart';
+import '../text/canvas_paragraph.dart';
 import '../util.dart';
 import '../vector_math.dart';
 import 'bitmap_canvas.dart';
@@ -584,7 +584,7 @@ class RecordingCanvas {
 
   void drawParagraph(ui.Paragraph paragraph, ui.Offset offset) {
     assert(!_recordingEnded);
-    final EngineParagraph engineParagraph = paragraph as EngineParagraph;
+    final CanvasParagraph engineParagraph = paragraph as CanvasParagraph;
     if (!engineParagraph.isLaidOut) {
       // Ignore non-laid out paragraphs. This matches Flutter's behavior.
       return;
@@ -1238,7 +1238,7 @@ class PaintDrawImageRect extends DrawCommand {
 }
 
 class PaintDrawParagraph extends DrawCommand {
-  final EngineParagraph paragraph;
+  final CanvasParagraph paragraph;
   final ui.Offset offset;
 
   PaintDrawParagraph(this.paragraph, this.offset);

lib/web_ui/lib/src/engine/text/canvas_paragraph.dart

@@ -22,7 +22,7 @@ const ui.Color _defaultTextColor = ui.Color(0xFFFF0000);
 /// [CanvasParagraph] doesn't use a DOM element to represent the structure of
 /// its spans and styles. Instead it uses a flat list of [ParagraphSpan]
 /// objects.
-class CanvasParagraph implements EngineParagraph {
+class CanvasParagraph implements ui.Paragraph {
   /// This class is created by the engine, and should not be instantiated
   /// or extended directly.
   ///
@@ -47,7 +47,7 @@ class CanvasParagraph implements EngineParagraph {
   /// The number of placeholders in this paragraph.
   final int placeholderCount;
 
-  @override
+  /// Whether this paragraph can be drawn on a bitmap canvas.
   final bool drawOnCanvas;
 
   @override
@@ -74,7 +74,7 @@ class CanvasParagraph implements EngineParagraph {
   @override
   bool get didExceedMaxLines => _layoutService.didExceedMaxLines;
 
-  @override
+  /// Whether this paragraph has been laid out or not.
   bool isLaidOut = false;
 
   bool get isRtl => paragraphStyle.effectiveTextDirection == ui.TextDirection.rtl;
@@ -119,20 +119,24 @@ class CanvasParagraph implements EngineParagraph {
 
   // TODO(mdebbar): Returning true means we always require a bitmap canvas. Revisit
   // this decision once `CanvasParagraph` is fully implemented.
-  @override
+  /// Whether this paragraph is doing arbitrary paint operations that require
+  /// a bitmap canvas, and can't be expressed in a DOM canvas.
   bool get hasArbitraryPaint => true;
 
-  @override
+  /// Paints this paragraph instance on a [canvas] at the given [offset].
   void paint(BitmapCanvas canvas, ui.Offset offset) {
     _paintService.paint(canvas, offset);
   }
 
-  @override
+  /// Generates a flat string computed from all the spans of the paragraph.
   String toPlainText() => plainText;
 
   html.HtmlElement? _cachedDomElement;
 
-  @override
+  /// Returns a DOM element that represents the entire paragraph and its
+  /// children.
+  ///
+  /// Generates a new DOM element on every invocation.
   html.HtmlElement toDomElement() {
     assert(isLaidOut);
     final html.HtmlElement? domElement = _cachedDomElement;

lib/web_ui/lib/src/engine/text/paragraph.dart

@@ -9,7 +9,6 @@ import 'package:ui/ui.dart' as ui;
 
 import '../browser_detection.dart';
 import '../embedder.dart';
-import '../html/bitmap_canvas.dart';
 import '../util.dart';
 import 'layout_service.dart';
 import 'ruler.dart';
@@ -182,31 +181,6 @@ class EngineLineMetrics implements ui.LineMetrics {
   }
 }
 
-/// Common interface for all the implementations of [ui.Paragraph] in the web
-/// engine.
-abstract class EngineParagraph implements ui.Paragraph {
-  /// Whether this paragraph has been laid out or not.
-  bool get isLaidOut;
-
-  /// Whether this paragraph can be drawn on a bitmap canvas.
-  bool get drawOnCanvas;
-
-  /// Whether this paragraph is doing arbitrary paint operations that require
-  /// a bitmap canvas, and can't be expressed in a DOM canvas.
-  bool get hasArbitraryPaint;
-
-  void paint(BitmapCanvas canvas, ui.Offset offset);
-
-  /// Generates a flat string computed from all the spans of the paragraph.
-  String toPlainText();
-
-  /// Returns a DOM element that represents the entire paragraph and its
-  /// children.
-  ///
-  /// Generates a new DOM element on every invocation.
-  html.HtmlElement toDomElement();
-}
-
 /// The web implementation of [ui.ParagraphStyle].
 class EngineParagraphStyle implements ui.ParagraphStyle {
   /// Creates a new instance of [EngineParagraphStyle].

lib/web_ui/lib/src/engine/text/ruler.dart

@@ -47,157 +47,9 @@ String buildCssFontString({
   return result.toString();
 }
 
-/// Contains the subset of [ui.ParagraphStyle] properties that affect layout.
-class ParagraphGeometricStyle {
-  ParagraphGeometricStyle({
-    required this.textDirection,
-    required this.textAlign,
-    this.fontWeight,
-    this.fontStyle,
-    this.fontFamily,
-    this.fontSize,
-    this.lineHeight,
-    this.maxLines,
-    this.letterSpacing,
-    this.wordSpacing,
-    this.decoration,
-    this.ellipsis,
-    this.shadows,
-  });
-
-  final ui.TextDirection textDirection;
-  final ui.TextAlign textAlign;
-  final ui.FontWeight? fontWeight;
-  final ui.FontStyle? fontStyle;
-  final String? fontFamily;
-  final double? fontSize;
-  final double? lineHeight;
-  final int? maxLines;
-  final double? letterSpacing;
-  final double? wordSpacing;
-  final String? decoration;
-  final String? ellipsis;
-  final List<ui.Shadow>? shadows;
-
-  // Since all fields above are primitives, cache hashcode since ruler lookups
-  // use this style as key.
-  int? _cachedHashCode;
-
-  /// Returns the font-family that should be used to style the paragraph. It may
-  /// or may not be different from [fontFamily]:
-  ///
-  /// - Always returns "Ahem" in tests.
-  /// - Provides correct defaults when [fontFamily] doesn't have a value.
-  String get effectiveFontFamily {
-    if (assertionsEnabled) {
-      // In widget tests we use a predictable-size font "Ahem". This makes
-      // widget tests predictable and less flaky.
-      if (ui.debugEmulateFlutterTesterEnvironment) {
-        return 'Ahem';
-      }
-    }
-    final String? localFontFamily = fontFamily;
-    if (localFontFamily == null || localFontFamily.isEmpty) {
-      return FlutterViewEmbedder.defaultFontFamily;
-    }
-    return localFontFamily;
-  }
-
-  String? _cssFontString;
-
-  /// Cached font string that can be used in CSS.
-  ///
-  /// See <https://developer.mozilla.org/en-US/docs/Web/CSS/font>.
-  String get cssFontString {
-    return _cssFontString ??= buildCssFontString(
-      fontStyle: fontStyle,
-      fontWeight: fontWeight,
-      fontSize: fontSize,
-      fontFamily: effectiveFontFamily,
-    );
-  }
-
-  TextHeightStyle? _cachedHeightStyle;
-
-  TextHeightStyle get textHeightStyle {
-    TextHeightStyle? style = _cachedHeightStyle;
-    if (style == null) {
-      style = TextHeightStyle(
-        fontFamily: effectiveFontFamily,
-        fontSize: fontSize ?? FlutterViewEmbedder.defaultFontSize,
-        height: lineHeight,
-        // TODO(mdebbar): Pass the actual value when font features become supported
-        //                https://github.com/flutter/flutter/issues/64595
-        fontFeatures: null,
-      );
-      _cachedHeightStyle = style;
-    }
-    return style;
-  }
-
-  @override
-  bool operator ==(Object other) {
-    if (identical(this, other)) {
-      return true;
-    }
-    if (other.runtimeType != runtimeType) {
-      return false;
-    }
-    return other is ParagraphGeometricStyle
-        && other.textDirection == textDirection
-        && other.textAlign == textAlign
-        && other.fontWeight == fontWeight
-        && other.fontStyle == fontStyle
-        && other.fontFamily == fontFamily
-        && other.fontSize == fontSize
-        && other.lineHeight == lineHeight
-        && other.maxLines == maxLines
-        && other.letterSpacing == letterSpacing
-        && other.wordSpacing == wordSpacing
-        && other.decoration == decoration
-        && other.ellipsis == ellipsis;
-  }
-
-  @override
-  int get hashCode => _cachedHashCode ??= ui.hashValues(
-        textDirection,
-        textAlign,
-        fontWeight,
-        fontStyle,
-        fontFamily,
-        fontSize,
-        lineHeight,
-        maxLines,
-        letterSpacing,
-        wordSpacing,
-        decoration,
-        ellipsis,
-      );
-
-  @override
-  String toString() {
-    if (assertionsEnabled) {
-      return '$runtimeType(textDirection: $textDirection, textAlign: $textAlign,'
-          ' fontWeight: $fontWeight,'
-          ' fontStyle: $fontStyle,'
-          ' fontFamily: $fontFamily, fontSize: $fontSize,'
-          ' lineHeight: $lineHeight,'
-          ' maxLines: $maxLines,'
-          ' letterSpacing: $letterSpacing,'
-          ' wordSpacing: $wordSpacing,'
-          ' decoration: $decoration,'
-          ' ellipsis: $ellipsis,'
-          ')';
-    } else {
-      return super.toString();
-    }
-  }
-}
-
 /// Contains all styles that have an effect on the height of text.
 ///
-/// This is useful as a cache key for [TextHeightRuler]. It's more efficient
-/// than using the entire [ParagraphGeometricStyle] as a cache key.
+/// This is useful as a cache key for [TextHeightRuler].
 class TextHeightStyle {
   TextHeightStyle({
     required this.fontFamily,

lib/web_ui/test/html/bitmap_canvas_golden_test.dart

@@ -147,9 +147,9 @@ Future<void> testMain() async {
   //
   // More details: https://github.com/flutter/flutter/issues/32274
   test('renders clipped DOM text with high quality', () async {
-    final EngineParagraph paragraph =
+    final CanvasParagraph paragraph =
         (ParagraphBuilder(ParagraphStyle(fontFamily: 'Roboto'))
-          ..addText('Am I blurry?')).build() as EngineParagraph;
+          ..addText('Am I blurry?')).build() as CanvasParagraph;
     paragraph.layout(const ParagraphConstraints(width: 1000));
 
     final Rect canvasSize = Rect.fromLTRB(
@@ -199,7 +199,7 @@ Future<void> testMain() async {
       'breaks into multiple lines.';
     builder.addText(text);
 
-    final EngineParagraph paragraph = builder.build() as EngineParagraph;
+    final CanvasParagraph paragraph = builder.build() as CanvasParagraph;
     paragraph.layout(const ParagraphConstraints(width: 100));
 
     final Rect canvasSize = Offset.zero & const Size(500, 500);

lib/web_ui/test/html/paragraph/text_overflow_golden_test.dart

@@ -30,7 +30,7 @@ Future<void> testMain() async {
 
   testEachCanvas('maxLines clipping', (EngineCanvas canvas) {
     Offset offset = Offset.zero;
-    EngineParagraph p;
+    CanvasParagraph p;
 
     // All three lines are rendered.
     p = paragraph(threeLines);

lib/web_ui/test/html/paragraph/text_scuba.dart

@@ -108,7 +108,7 @@ final ui.TextStyle _defaultTextStyle = ui.TextStyle(
   fontSize: 14,
 );
 
-EngineParagraph paragraph(
+CanvasParagraph paragraph(
   String text, {
   ui.ParagraphStyle? paragraphStyle,
   ui.TextStyle? textStyle,
@@ -119,7 +119,7 @@ EngineParagraph paragraph(
   builder.pushStyle(textStyle ?? _defaultTextStyle);
   builder.addText(text);
   builder.pop();
-  final EngineParagraph paragraph = builder.build() as EngineParagraph;
+  final CanvasParagraph paragraph = builder.build() as CanvasParagraph;
   paragraph.layout(ui.ParagraphConstraints(width: maxWidth));
   return paragraph;
 }