Adds TextStyle decoration, decorationColor, decorationStyle

sky/sdk/lib/painting/text_style.dart

Index: sky/sdk/lib/painting/text_style.dart
diff --git a/sky/sdk/lib/painting/text_style.dart b/sky/sdk/lib/painting/text_style.dart
index d45929991b6007fb77c11a8b16e15cd62d4e933e..43e27e982a0c92e94d65fd09ae28929aafe9d47f 100644
--- a/sky/sdk/lib/painting/text_style.dart
+++ b/sky/sdk/lib/painting/text_style.dart
@@ -32,13 +32,35 @@ enum TextAlign {
   center
 }
 
+enum TextDecoration {
+  none,
+  underline,
+  overline,
+  lineThrough
+}
+
+const underline = const <TextDecoration> [TextDecoration.underline];
+const overline = const <TextDecoration> [TextDecoration.overline];
+const lineThrough = const <TextDecoration> [TextDecoration.lineThrough];
+
+enum TextDecorationStyle {
+  solid,
+  double,
+  dotted,
+  dashed,
+  wavy
+}
+
 class TextStyle {
   const TextStyle({
     this.color,
     this.fontFamily,
     this.fontSize,
     this.fontWeight,
-    this.textAlign
+    this.textAlign,
+    List<TextDecoration> this.decoration,
+    this.decorationColor,
+    this.decorationStyle
   });
 
   final Color color;
@@ -46,19 +68,39 @@ class TextStyle {
   final double fontSize; // in pixels
   final FontWeight fontWeight;
   final TextAlign textAlign;
+  final List<TextDecoration> decoration;
+  final Color decorationColor;
+  final TextDecorationStyle decorationStyle;
+
+  String _decorationToString() {
+    assert(decoration != null);
+    const toCSS = const {
+      TextDecoration.none: 'none',
+      TextDecoration.underline: 'underline',
+      TextDecoration.overline: 'overline',
+      TextDecoration.lineThrough: 'lineThrough'
+    };
+    return decoration.map((d) => toCSS[d]).join(' ');
+  }
 
   TextStyle copyWith({
     Color color,
     double fontSize,
     FontWeight fontWeight,
-    TextAlign textAlign
+    TextAlign textAlign,
+    TextDecoration decoration,
+    Color decorationColor,
+    TextDecorationStyle decorationStyle
   }) {
     return new TextStyle(
       color: color != null ? color : this.color,
       fontFamily: fontFamily != null ? fontFamily : this.fontFamily,
       fontSize: fontSize != null ? fontSize : this.fontSize,
       fontWeight: fontWeight != null ? fontWeight : this.fontWeight,
-      textAlign: textAlign != null ? textAlign : this.textAlign
+      textAlign: textAlign != null ? textAlign : this.textAlign,
+      decoration: decoration != null ? decoration : this.decoration,
+      decorationColor: decorationColor != null ? decorationColor : this.decorationColor,
+      decorationStyle: decorationStyle != null ? decorationStyle : this.decorationStyle
     );
   }
 
@@ -68,7 +110,10 @@ class TextStyle {
       fontFamily == other.fontFamily && 
       fontSize == other.fontSize &&
       fontWeight == other.fontWeight &&
-      textAlign == other.textAlign;
+      textAlign == other.textAlign && 
+      decoration == other.decoration &&
+      decorationColor == other.decorationColor &&
+      decorationStyle == other.decorationStyle;
   }
 
   int get hashCode {
@@ -79,6 +124,9 @@ class TextStyle {
     value = 37 * value + fontSize.hashCode;
     value = 37 * value + fontWeight.hashCode;
     value = 37 * value + textAlign.hashCode;
+    value = 37 * value + decoration.hashCode;
+    value = 37 * value + decorationColor.hashCode;
+    value = 37 * value + decorationStyle.hashCode;
     return value;
   }
 
@@ -113,6 +161,10 @@ class TextStyle {
         TextAlign.center: 'center',
       }[textAlign];
     }
+    if (decoration != null) {
+      cssStyle['text-decoration'] = _decorationToString();
+    }
+    // TODO(hansmuller): add support for decoration color and style.
   }
 
   String toString([String prefix = '']) {
@@ -128,6 +180,12 @@ class TextStyle {
       result.add('${prefix}fontWeight: $fontWeight');
     if (textAlign != null)
       result.add('${prefix}textAlign: $textAlign');
+    if (decoration != null)
+      result.add('${prefix}decoration: ${_decorationToString()}');
+    if (decorationColor != null)
+      result.add('${prefix}decorationColor: $decorationColor');
+    if (decorationStyle != null)
+      result.add('${prefix}decorationStyle: $decorationStyle');
     if (result.isEmpty)
       return '${prefix}<no style specified>';
     return result.join('\n');