Optimized the border radius converter and initial values

CHANGELOG.md

@@ -1,6 +1,6 @@
 # 0.12.0
 
-Released on Thursday, May 5 2019.
+Released on Sunday, May 12 2019.
 
 - Reference latest AngleSharp
 - Fixed empty value when removing properties (#14)
@@ -10,6 +10,7 @@ Released on Thursday, May 5 2019.
 - Fixed exception when not providing an `IRenderDevice` (#20)
 - Fixed missing `CssStylingService.Default` in cascade (#21)
 - Added extension helper `SetStyle` to modify all styles of many elements (#22)
+- Fixed expansion of shorthand properties to longhand (#23)
 - Opened CSSOM, e.g., declared `ICssFunctionValue` `public` (#24)
 - Introduced special converter for the `src` declaration (#25)
 - Fixed bug regarding CSS grid serialization (#27)

src/AngleSharp.Css.Tests/Declarations/CssBorderRadiusProperty.cs

@@ -15,7 +15,7 @@ namespace AngleSharp.Css.Tests.Declarations
             Assert.IsFalse(property.IsImportant);
             Assert.IsFalse(property.IsInherited);
             Assert.IsTrue(property.HasValue);
-            Assert.AreEqual("40px 40px", property.Value);
+            Assert.AreEqual("40px", property.Value);
         }
 
         [Test]

src/AngleSharp.Css/Constants/InitialValues.cs

@@ -29,6 +29,9 @@ namespace AngleSharp.Css
         public static readonly ICssValue FontStretchDecl = new Constant<FontStretch>(CssKeywords.Normal, FontStretch.Normal);
         public static readonly ICssValue FontSizeDecl = new Constant<Length>(CssKeywords.Medium, Length.Medium);
         public static readonly ICssValue FontFamilyDecl = new Label("Times New Roman");
+        public static readonly ICssValue BorderWidthDecl = new Constant<Length>(CssKeywords.Medium, Length.Medium);
+        public static readonly ICssValue BorderStyleDecl = new Constant<LineStyle>(CssKeywords.None, LineStyle.None);
+        public static readonly ICssValue BorderColorDecl = new Constant<Color>(CssKeywords.CurrentColor, Color.CurrentColor);
         public static readonly ICssValue LineHeightDecl = new Constant<Length>(CssKeywords.Normal, Length.Normal);
         public static readonly ICssValue BorderTopWidthDecl = new Constant<Length>(CssKeywords.Medium, Length.Medium);
         public static readonly ICssValue BorderRightWidthDecl = new Constant<Length>(CssKeywords.Medium, Length.Medium);

src/AngleSharp.Css/Converters/OptionValueConverter.cs

@@ -4,12 +4,12 @@ namespace AngleSharp.Css.Converters
     using AngleSharp.Css.Values;
     using AngleSharp.Text;
 
-    sealed class OptionValueConverter<T> : IValueConverter
+    sealed class OptionValueConverter : IValueConverter
     {
         private readonly IValueConverter _converter;
-        private readonly T _defaultValue;
+        private readonly ICssValue _defaultValue;
 
-        public OptionValueConverter(IValueConverter converter, T defaultValue)
+        public OptionValueConverter(IValueConverter converter, ICssValue defaultValue)
         {
             _converter = converter;
             _defaultValue = defaultValue;
@@ -19,7 +19,7 @@ namespace AngleSharp.Css.Converters
         {
             if (source.IsDone || source.Current == Symbols.Comma)
             {
-                return new CssDefaultValue<T>(_defaultValue);
+                return new CssDefaultValue(_defaultValue);
             }
 
             return _converter.Convert(source);

src/AngleSharp.Css/Converters/RadiusValueConverter.cs

@@ -0,0 +1,44 @@
+namespace AngleSharp.Css.Converters
+{
+    using AngleSharp.Css.Dom;
+    using AngleSharp.Css.Parser;
+    using AngleSharp.Css.Values;
+    using AngleSharp.Text;
+    using System;
+
+    sealed class RadiusValueConverter : IValueConverter
+    {
+        private readonly IValueConverter _converter;
+
+        public RadiusValueConverter(IValueConverter converter)
+        {
+            _converter = converter;
+        }
+
+        public ICssValue Convert(StringSource source)
+        {
+            var options = new ICssValue[2];
+            var length = 0;
+
+            for (var i = 0; i < options.Length; i++)
+            {
+                options[i] = _converter.Convert(source);
+                source.SkipSpacesAndComments();
+
+                if (options[length] != null)
+                {
+                    length++;
+                }
+            }
+
+            if (length > 0)
+            {
+                var values = new ICssValue[length];
+                Array.Copy(options, values, length);
+                return new CssRadiusValue(values);
+            }
+
+            return null;
+        }
+    }
+}

src/AngleSharp.Css/Converters/ValueConverterExtensions.cs

@@ -39,6 +39,9 @@ namespace AngleSharp.Css.Converters
         public static IValueConverter Periodic(this IValueConverter converter) =>
             new PeriodicValueConverter(converter);
 
+        public static IValueConverter Radius(this IValueConverter converter) =>
+            new RadiusValueConverter(converter);
+
         public static IValueConverter Exclusive(this IValueConverter converter)
         {
             return new ClassValueConverter<ICssValue>(source =>
@@ -57,11 +60,8 @@ namespace AngleSharp.Css.Converters
             });
         }
 
-        public static IValueConverter Option(this IValueConverter converter) =>
-            new OptionValueConverter<Object>(converter, null);
-
-        public static IValueConverter Option<T>(this IValueConverter converter, T defaultValue) =>
-            new OptionValueConverter<T>(converter, defaultValue);
+        public static IValueConverter Option(this IValueConverter converter, ICssValue defaultValue) =>
+            new OptionValueConverter(converter, defaultValue);
 
         public static String Join<T>(this T[] values, String separator)
             where T : ICssValue

src/AngleSharp.Css/Declarations/AnimationDeclaration.cs

@@ -33,14 +33,14 @@ namespace AngleSharp.Css.Declarations
         sealed class AnimationAggregator : IValueAggregator, IValueConverter
         {
             private static readonly IValueConverter ListConverter = WithAny(
-                TimeConverter.Option(),
-                TransitionConverter.Option(),
-                TimeConverter.Option(),
-                PositiveOrInfiniteNumberConverter.Option(),
-                AnimationDirectionConverter.Option(),
-                AnimationFillStyleConverter.Option(),
-                PlayStateConverter.Option(),
-                IdentifierConverter.Option()).FromList();
+                TimeConverter.Option(InitialValues.AnimationDurationDecl),
+                TransitionConverter.Option(InitialValues.AnimationTimingFunctionDecl),
+                TimeConverter.Option(InitialValues.AnimationDelayDecl),
+                PositiveOrInfiniteNumberConverter.Option(InitialValues.AnimationIterationCountDecl),
+                AnimationDirectionConverter.Option(InitialValues.AnimationDirectionDecl),
+                AnimationFillStyleConverter.Option(InitialValues.AnimationFillModeDecl),
+                PlayStateConverter.Option(InitialValues.AnimationPlayStateDecl),
+                IdentifierConverter.Option(InitialValues.AnimationNameDecl)).FromList();
 
             public ICssValue Convert(StringSource source) => ListConverter.Convert(source);
 

src/AngleSharp.Css/Declarations/BorderBottomDeclaration.cs

@@ -8,17 +8,20 @@ namespace AngleSharp.Css.Declarations
     {
         public static String Name = PropertyNames.BorderBottom;
 
-        public static IValueConverter Converter = AggregateTuple(BorderSideConverter);
-
-        public static ICssValue InitialValue = null;
-
-        public static PropertyFlags Flags = PropertyFlags.Animatable | PropertyFlags.Shorthand;
-
         public static String[] Shorthands = new[]
         {
             PropertyNames.Border,
         };
 
+        public static IValueConverter Converter = WithBorderSide(
+            InitialValues.BorderBottomWidthDecl,
+            InitialValues.BorderBottomStyleDecl,
+            InitialValues.BorderBottomColorDecl);
+
+        public static ICssValue InitialValue = null;
+
+        public static PropertyFlags Flags = PropertyFlags.Animatable | PropertyFlags.Shorthand;
+
         public static String[] Longhands = new[]
         {
             PropertyNames.BorderBottomWidth,

src/AngleSharp.Css/Declarations/BorderDeclaration.cs

@@ -25,19 +25,12 @@ namespace AngleSharp.Css.Declarations
             PropertyNames.BorderColor,
         };
 
-        sealed class BorderValueConverter : IValueConverter
-        {
-            private static readonly IValueConverter converter = WithAny(
-                LineWidthConverter.Option(),
-                LineStyleConverter.Option(),
-                CurrentColorConverter.Option());
-
-            public ICssValue Convert(StringSource source) => converter.Convert(source);
-        }
-
         sealed class BorderAggregator : IValueAggregator, IValueConverter
         {
-            private static readonly IValueConverter converter = new BorderValueConverter();
+            private static readonly IValueConverter converter = WithAny(
+                LineWidthConverter.Option(InitialValues.BorderWidthDecl),
+                LineStyleConverter.Option(InitialValues.BorderStyleDecl),
+                CurrentColorConverter.Option(InitialValues.BorderColorDecl));
 
             public ICssValue Convert(StringSource source) => converter.Convert(source);
 

src/AngleSharp.Css/Declarations/BorderLeftDeclaration.cs

@@ -13,7 +13,10 @@ namespace AngleSharp.Css.Declarations
             PropertyNames.Border,
         };
 
-        public static IValueConverter Converter = AggregateTuple(BorderSideConverter);
+        public static IValueConverter Converter = WithBorderSide(
+            InitialValues.BorderLeftWidthDecl,
+            InitialValues.BorderLeftStyleDecl,
+            InitialValues.BorderLeftColorDecl);
 
         public static ICssValue InitialValue = null;
 

src/AngleSharp.Css/Declarations/BorderRadiusDeclaration.cs

@@ -26,7 +26,7 @@ namespace AngleSharp.Css.Declarations
             PropertyNames.BorderBottomLeftRadius,
         };
 
-        sealed class BorderRadiusValueConverter : IValueConverter
+        sealed class BorderRadiusAggregator : IValueAggregator, IValueConverter
         {
             private readonly IValueConverter _converter = LengthOrPercentConverter.Periodic();
 
@@ -45,33 +45,20 @@ namespace AngleSharp.Css.Declarations
 
                 return vertical != null ? new CssBorderRadiusValue(horizontal, vertical) : null;
             }
-        }
 
-        sealed class BorderRadiusAggregator : IValueAggregator, IValueConverter
-        {
-            private static readonly IValueConverter converter = new BorderRadiusValueConverter();
-
-            public ICssValue Convert(StringSource source)
-            {
-                return converter.Convert(source);
-            }
-
-            private static ICssValue Both(ICssValue horizontal, ICssValue vertical)
-            {
-                return new CssTupleValue(new[] { horizontal, vertical });
-            }
+            private static ICssValue Both(params ICssValue[] values) => new CssRadiusValue(values);
 
             public ICssValue Merge(ICssValue[] values)
             {
-                var topLeft = values[0] as CssTupleValue;
-                var topRight = values[1] as CssTupleValue;
-                var bottomRight = values[2] as CssTupleValue;
-                var bottomLeft = values[3] as CssTupleValue;
+                var topLeft = values[0] as CssRadiusValue;
+                var topRight = values[1] as CssRadiusValue;
+                var bottomRight = values[2] as CssRadiusValue;
+                var bottomLeft = values[3] as CssRadiusValue;
 
                 if (topLeft != null && topRight != null && bottomRight != null && bottomLeft != null)
                 {
-                    var horizontal = new CssPeriodicValue(new[] { topLeft.Items[0], topRight.Items[0], bottomRight.Items[0], bottomLeft.Items[0] });
-                    var vertical = new CssPeriodicValue(new[] { topLeft.Items[1], topRight.Items[1], bottomRight.Items[1], bottomLeft.Items[1] });
+                    var horizontal = new CssPeriodicValue(new[] { topLeft.Width, topRight.Width, bottomRight.Width, bottomLeft.Width });
+                    var vertical = new CssPeriodicValue(new[] { topLeft.Height, topRight.Height, bottomRight.Height, bottomLeft.Height });
                     return new CssBorderRadiusValue(horizontal, vertical);
                 }
 

src/AngleSharp.Css/Declarations/BorderRightDeclaration.cs

@@ -13,7 +13,10 @@ namespace AngleSharp.Css.Declarations
             PropertyNames.Border,
         };
 
-        public static IValueConverter Converter = AggregateTuple(BorderSideConverter);
+        public static IValueConverter Converter = WithBorderSide(
+            InitialValues.BorderRightWidthDecl,
+            InitialValues.BorderRightStyleDecl,
+            InitialValues.BorderRightColorDecl);
 
         public static ICssValue InitialValue = null;
 

src/AngleSharp.Css/Declarations/BorderTopDeclaration.cs

@@ -13,7 +13,10 @@ namespace AngleSharp.Css.Declarations
             PropertyNames.Border,
         };
 
-        public static IValueConverter Converter = AggregateTuple(BorderSideConverter);
+        public static IValueConverter Converter = WithBorderSide(
+            InitialValues.BorderTopWidthDecl,
+            InitialValues.BorderTopStyleDecl,
+            InitialValues.BorderTopColorDecl);
 
         public static ICssValue InitialValue = null;
 

src/AngleSharp.Css/Declarations/ListStyleDeclaration.cs

@@ -2,8 +2,6 @@ namespace AngleSharp.Css.Declarations
 {
     using AngleSharp.Css.Converters;
     using AngleSharp.Css.Dom;
-    using AngleSharp.Css.Values;
-    using AngleSharp.Text;
     using System;
     using static ValueConverters;
 
@@ -11,7 +9,11 @@ namespace AngleSharp.Css.Declarations
     {
         public static String Name = PropertyNames.ListStyle;
 
-        public static IValueConverter Converter = new ListStyleAggregator();
+        public static IValueConverter Converter = AggregateTuple(
+            WithAny(
+                ListStyleConverter.Option(InitialValues.ListStyleTypeDecl),
+                ListPositionConverter.Option(InitialValues.ListStylePositionDecl),
+                OptionalImageSourceConverter.Option(InitialValues.ListStyleImageDecl)));
 
         public static ICssValue InitialValue = null;
 
@@ -23,59 +25,5 @@ namespace AngleSharp.Css.Declarations
             PropertyNames.ListStylePosition,
             PropertyNames.ListStyleImage,
         };
-
-        sealed class ListStyleValueConverter : IValueConverter
-        {
-            private static readonly IValueConverter converter = WithAny(
-                ListStyleConverter.Option(),
-                ListPositionConverter.Option(),
-                OptionalImageSourceConverter.Option());
-
-            public ICssValue Convert(StringSource source)
-            {
-                return converter.Convert(source);
-            }
-        }
-
-        sealed class ListStyleAggregator : IValueAggregator, IValueConverter
-        {
-            private static readonly IValueConverter converter = new ListStyleValueConverter();
-
-            public ICssValue Convert(StringSource source)
-            {
-                return converter.Convert(source);
-            }
-
-            public ICssValue Merge(ICssValue[] values)
-            {
-                var type = values[0];
-                var position = values[1];
-                var image = values[2];
-
-                if (type != null || position != null || image != null)
-                {
-                    return new CssTupleValue(new[] { type, position, image });
-                }
-
-                return null;
-            }
-
-            public ICssValue[] Split(ICssValue value)
-            {
-                var options = value as CssTupleValue;
-
-                if (options != null)
-                {
-                    return new[]
-                    {
-                        options.Items[0],
-                        options.Items[1],
-                        options.Items[2],
-                    };
-                }
-
-                return null;
-            }
-        }
     }
 }

src/AngleSharp.Css/Declarations/OutlineDeclaration.cs

@@ -2,8 +2,6 @@ namespace AngleSharp.Css.Declarations
 {
     using AngleSharp.Css.Converters;
     using AngleSharp.Css.Dom;
-    using AngleSharp.Css.Values;
-    using AngleSharp.Text;
     using System;
     using static ValueConverters;
 
@@ -11,7 +9,11 @@ namespace AngleSharp.Css.Declarations
     {
         public static String Name = PropertyNames.Outline;
 
-        public static IValueConverter Converter = new OutlineAggregator();
+        public static IValueConverter Converter = AggregateTuple(
+            WithAny(
+                LineWidthConverter.Option(InitialValues.OutlineWidthDecl),
+                LineStyleConverter.Option(InitialValues.OutlineStyleDecl),
+                InvertedColorConverter.Option(InitialValues.OutlineColorDecl)));
 
         public static ICssValue InitialValue = null;
 
@@ -23,59 +25,5 @@ namespace AngleSharp.Css.Declarations
             PropertyNames.OutlineStyle,
             PropertyNames.OutlineColor,
         };
-
-        sealed class OutlineValueConverter : IValueConverter
-        {
-            private static readonly IValueConverter converter = WithAny(
-                LineWidthConverter.Option(),
-                LineStyleConverter.Option(),
-                InvertedColorConverter.Option());
-
-            public ICssValue Convert(StringSource source)
-            {
-                return converter.Convert(source);
-            }
-        }
-
-        sealed class OutlineAggregator : IValueAggregator, IValueConverter
-        {
-            private static readonly IValueConverter converter = new OutlineValueConverter();
-
-            public ICssValue Convert(StringSource source)
-            {
-                return converter.Convert(source);
-            }
-
-            public ICssValue Merge(ICssValue[] values)
-            {
-                var width = values[0];
-                var style = values[1];
-                var color = values[2];
-
-                if (width != null || style != null || color != null)
-                {
-                    return new CssTupleValue(new[] { width, style, color });
-                }
-
-                return null;
-            }
-
-            public ICssValue[] Split(ICssValue value)
-            {
-                var options = value as CssTupleValue;
-
-                if (options != null)
-                {
-                    return new[]
-                    {
-                        options.Items[0],
-                        options.Items[1],
-                        options.Items[2],
-                    };
-                }
-
-                return null;
-            }
-        }
     }
 }

src/AngleSharp.Css/Declarations/TextDecorationDeclaration.cs

@@ -2,8 +2,6 @@ namespace AngleSharp.Css.Declarations
 {
     using AngleSharp.Css.Converters;
     using AngleSharp.Css.Dom;
-    using AngleSharp.Css.Values;
-    using AngleSharp.Text;
     using System;
     using static ValueConverters;
 
@@ -11,7 +9,11 @@ namespace AngleSharp.Css.Declarations
     {
         public static String Name = PropertyNames.TextDecoration;
 
-        public static IValueConverter Converter = new TextDecorationAggregator();
+        public static IValueConverter Converter = AggregateTuple(
+            WithAny(
+                ColorConverter.Option(InitialValues.TextDecorationColorDecl),
+                TextDecorationStyleConverter.Option(InitialValues.TextDecorationLineDecl),
+                TextDecorationLinesConverter.Option(InitialValues.TextDecorationStyleDecl)));
 
         public static ICssValue InitialValue = null;
 
@@ -23,59 +25,5 @@ namespace AngleSharp.Css.Declarations
             PropertyNames.TextDecorationLine,
             PropertyNames.TextDecorationStyle,
         };
-
-        sealed class TextDecorationValueConverter : IValueConverter
-        {
-            private static readonly IValueConverter converter = WithAny(
-                ColorConverter.Option(),
-                TextDecorationStyleConverter.Option(),
-                TextDecorationLinesConverter.Option());
-
-            public ICssValue Convert(StringSource source)
-            {
-                return converter.Convert(source);
-            }
-        }
-
-        sealed class TextDecorationAggregator : IValueAggregator, IValueConverter
-        {
-            private static readonly IValueConverter converter = new TextDecorationValueConverter();
-
-            public ICssValue Convert(StringSource source)
-            {
-                return converter.Convert(source);
-            }
-
-            public ICssValue Merge(ICssValue[] values)
-            {
-                var color = values[0];
-                var line = values[1];
-                var style = values[2];
-
-                if (color != null || style != null || line != null)
-                {
-                    return new CssTupleValue(new[] { color, style, line });
-                }
-
-                return null;
-            }
-
-            public ICssValue[] Split(ICssValue value)
-            {
-                var options = value as CssTupleValue;
-
-                if (options != null)
-                {
-                    return new[]
-                    {
-                        options.Items[0],
-                        options.Items[1],
-                        options.Items[2],
-                    };
-                }
-
-                return null;
-            }
-        }
     }
 }

src/AngleSharp.Css/Declarations/TransitionDeclaration.cs

@@ -26,20 +26,13 @@ namespace AngleSharp.Css.Declarations
             PropertyNames.TransitionDelay,
         };
 
-        sealed class TransitionValueConverter : IValueConverter
-        {
-            private static readonly IValueConverter converter = WithAny(
-                AnimatableConverter.Option(),
-                TimeConverter.Option(),
-                TransitionConverter.Option(),
-                TimeConverter.Option()).FromList();
-
-            public ICssValue Convert(StringSource source) => converter.Convert(source);
-        }
-
         sealed class TransitionAggregator : IValueAggregator, IValueConverter
         {
-            private static readonly IValueConverter converter = new TransitionValueConverter();
+            private static readonly IValueConverter converter = WithAny(
+                AnimatableConverter.Option(InitialValues.TransitionPropertyDecl),
+                TimeConverter.Option(InitialValues.TransitionDurationDecl),
+                TransitionConverter.Option(InitialValues.TransitionTimingFunctionDecl),
+                TimeConverter.Option(InitialValues.TransitionDelayDecl)).FromList();
 
             public ICssValue Convert(StringSource source) => converter.Convert(source);
 

src/AngleSharp.Css/FeatureValidators/ColorFeatureValidator.cs

@@ -1,7 +1,8 @@
-namespace AngleSharp.Css.FeatureValidators
+namespace AngleSharp.Css.FeatureValidators
 {
     using AngleSharp.Css.Converters;
     using AngleSharp.Css.Dom;
+    using AngleSharp.Css.Values;
     using System;
     using static ValueConverters;
 
@@ -9,7 +10,8 @@
     {
         public Boolean Validate(IMediaFeature feature, IRenderDevice device)
         {
-            var converter = feature.IsMinimum || feature.IsMaximum ? PositiveIntegerConverter : PositiveIntegerConverter.Option(1);
+            var defaultValue = new Length(1.0, Length.Unit.None);
+            var converter = feature.IsMinimum || feature.IsMaximum ? PositiveIntegerConverter : PositiveIntegerConverter.Option(defaultValue);
             var color = converter.Convert(feature.Value);
 
             if (color != null)

src/AngleSharp.Css/FeatureValidators/ColorIndexFeatureValidator.cs

@@ -1,7 +1,8 @@
-namespace AngleSharp.Css.FeatureValidators
+namespace AngleSharp.Css.FeatureValidators
 {
     using AngleSharp.Css.Converters;
     using AngleSharp.Css.Dom;
+    using AngleSharp.Css.Values;
     using System;
     using static ValueConverters;
 
@@ -9,7 +10,8 @@
     {
         public Boolean Validate(IMediaFeature feature, IRenderDevice device)
         {
-            var converter = feature.IsMinimum || feature.IsMaximum ? NaturalIntegerConverter : NaturalIntegerConverter.Option(1);
+            var defaultValue = new Length(1.0, Length.Unit.None);
+            var converter = feature.IsMinimum || feature.IsMaximum ? NaturalIntegerConverter : NaturalIntegerConverter.Option(defaultValue);
             var index = converter.Convert(feature.Value);
 
             if (index != null)

src/AngleSharp.Css/FeatureValidators/MonochromeFeatureValidator.cs

@@ -1,7 +1,8 @@
-namespace AngleSharp.Css.FeatureValidators
+namespace AngleSharp.Css.FeatureValidators
 {
     using AngleSharp.Css.Converters;
     using AngleSharp.Css.Dom;
+    using AngleSharp.Css.Values;
     using System;
     using static ValueConverters;
 
@@ -9,7 +10,8 @@
     {
         public Boolean Validate(IMediaFeature feature, IRenderDevice device)
         {
-            var converter = feature.IsMinimum || feature.IsMaximum ? NaturalIntegerConverter : NaturalIntegerConverter.Option(1);
+            var defaultValue = new Length(1.0, Length.Unit.None);
+            var converter = feature.IsMinimum || feature.IsMaximum ? NaturalIntegerConverter : NaturalIntegerConverter.Option(defaultValue);
             var index = converter.Convert(feature.Value);
 
             if (index != null)

src/AngleSharp.Css/ValueConverters.cs

@@ -699,9 +699,7 @@ namespace AngleSharp.Css
         /// <summary>
         /// Represents the border-radius (horizontal / vertical; radius) converter.
         /// </summary>
-        public static readonly IValueConverter BorderRadiusLonghandConverter = WithOrder(
-            LengthOrPercentConverter,
-            LengthOrPercentConverter.Option());
+        public static readonly IValueConverter BorderRadiusLonghandConverter = LengthOrPercentConverter.Radius();
 
         /// <summary>
         /// Represents a converter for font families.
@@ -840,7 +838,11 @@ namespace AngleSharp.Css
 
         #region Premade
 
-        public static readonly IValueConverter BorderSideConverter = WithAny(LineWidthConverter.Option(), LineStyleConverter.Option(), CurrentColorConverter.Option());
+        public static IValueConverter WithBorderSide(ICssValue lineWidth, ICssValue lineStyle, ICssValue lineColor) => AggregateTuple(
+            WithAny(
+                LineWidthConverter.Option(lineWidth),
+                LineStyleConverter.Option(lineStyle),
+                CurrentColorConverter.Option(lineColor)));
 
         public static readonly IValueConverter GridTemplateConverter = Or(None, TrackListConverter.Exclusive(), AutoTrackListConverter.Exclusive());
 

src/AngleSharp.Css/Values/Multiples/CssRadiusValue.cs

@@ -0,0 +1,114 @@
+namespace AngleSharp.Css.Values
+{
+    using AngleSharp.Css.Dom;
+    using AngleSharp.Text;
+    using System;
+    using System.Collections;
+    using System.Collections.Generic;
+
+    /// <summary>
+    /// Represents a periodic CSS value.
+    /// </summary>
+    public class CssRadiusValue<T> : ICssMultipleValue
+        where T : ICssValue
+    {
+        #region Fields
+
+        private readonly T[] _values;
+
+        #endregion
+
+        #region ctor
+
+        /// <summary>
+        /// Creates a new CSS radius value container.
+        /// </summary>
+        /// <param name="values">The items to contain.</param>
+        public CssRadiusValue(T[] values = null)
+        {
+            _values = values ?? Array.Empty<T>();
+        }
+
+        #endregion
+
+        #region Properties
+
+        /// <inheritdoc />
+        public ICssValue this[Int32 index]
+        {
+            get
+            {
+                switch (index)
+                {
+                    case 0:
+                        return Width;
+                    case 1:
+                        return Height;
+                    default:
+                        throw new ArgumentOutOfRangeException(nameof(index));
+                }
+            }
+        }
+
+        /// <inheritdoc />
+        public String CssText
+        {
+            get
+            {
+                var l = _values.Length;
+                var parts = new String[l];
+
+                for (var i = 0; i < l; i++)
+                {
+                    parts[i] = _values[i].CssText;
+                }
+
+                if (l == 2 && parts[1].Is(parts[0]))
+                {
+                    l = 1;
+                    parts = new[] { parts[0] };
+                }
+
+                return String.Join(" ", parts);
+            }
+        }
+
+        /// <inheritdoc />
+        public T Width => _values.Length > 0 ? _values[0] : default(T);
+
+        /// <inheritdoc />
+        public T Height => _values.Length > 1 ? _values[1] : Width;
+
+        /// <inheritdoc />
+        public Int32 Count => 2;
+
+        #endregion
+
+        #region Methods
+
+        IEnumerator<ICssValue> IEnumerable<ICssValue>.GetEnumerator()
+        {
+            yield return Width;
+            yield return Height;
+        }
+
+        IEnumerator IEnumerable.GetEnumerator() => ((IEnumerable<ICssValue>)this).GetEnumerator();
+
+        #endregion
+    }
+
+    /// <summary>
+    /// Represents a radius (w, h) CSS value.
+    /// </summary>
+    sealed class CssRadiusValue : CssRadiusValue<ICssValue>
+    {
+        #region ctor
+
+        public CssRadiusValue(ICssValue[] values = null)
+            : base(values)
+        {
+        }
+
+        #endregion
+    }
+}

src/AngleSharp.Css/Values/Raws/CssDefaultValue.cs

@@ -6,11 +6,11 @@ namespace AngleSharp.Css.Values
     /// <summary>
     /// Represents a default value.
     /// </summary>
-    sealed class CssDefaultValue<T> : ICssValue
+    sealed class CssDefaultValue : ICssValue
     {
         #region Fields
 
-        private readonly T _value;
+        private readonly ICssValue _value;
 
         #endregion
 
@@ -20,7 +20,7 @@ namespace AngleSharp.Css.Values
         /// Creates a new default value.
         /// </summary>
         /// <param name="value">The used value.</param>
-        public CssDefaultValue(T value)
+        public CssDefaultValue(ICssValue value)
         {
             _value = value;
         }
@@ -37,7 +37,7 @@ namespace AngleSharp.Css.Values
         /// <summary>
         /// Gets the default value.
         /// </summary>
-        public T Value => _value;
+        public ICssValue Value => _value;
 
         #endregion
     }