Updated media parsing #133

Author: FlorianRappl

CHANGELOG.md

@@ -3,6 +3,7 @@
 Released on tbd.
 
 - Updated to use AngleSharp 1.0
+- Updated media parsing to media L4 spec (#133)
 - Fixed issue when updating shorthands with invalid values (#129)
 - Fixed issue with appended EOF character in `CssText` (#123)
 - Fixed missing semicolon in `@page` rule (#135)

src/AngleSharp.Css.Tests/CssConstructionFunctions.cs

@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Tests
 {
     using AngleSharp.Css.Dom;
     using AngleSharp.Css.Parser;
+    using AngleSharp.Css.Values;
     using AngleSharp.Html.Dom;
     using AngleSharp.Html.Parser;
     using System;
@@ -70,7 +71,6 @@ internal static CssProperty ParseDeclaration(String source, CssParserOptions opt
         internal static CssStyleDeclaration ParseDeclarations(String declarations)
         {
             var context = BrowsingContext.New(Configuration.Default.WithCss());
-            var parser = context.GetService<ICssParser>();
             var style = new CssStyleDeclaration(context);
             style.Update(declarations);
             return style;
@@ -93,7 +93,7 @@ internal static CssImportRule ParseImportRule(String source)
         internal static Predicate<IRenderDevice> CreateValidator(String name, String value)
         {
             var validator = CreateMediaFeatureValidator(name);
-            var feature = new MediaFeature(name, value);
+            var feature = new MediaFeature(name, new CssAnyValue(value));
             return device => validator.Validate(feature, device);
         }
 

src/AngleSharp.Css.Tests/Rules/CssMediaList.cs

@@ -132,7 +132,7 @@ public void FeatureMinWidthMediaList()
         }
 
         [Test]
-        public void OnlyFeatureWidthMediaList()
+        public void OnlyFeatureWidthMediaListInvalid()
         {
             var source = @"@media only (width: 640px) {
     h1 { color: green }
@@ -141,7 +141,23 @@ public void OnlyFeatureWidthMediaList()
             Assert.AreEqual(1, sheet.Rules.Length);
             Assert.IsInstanceOf<CssMediaRule>(sheet.Rules[0]);
             var media = (CssMediaRule)sheet.Rules[0];
-            Assert.AreEqual("only (width: 640px)", media.Media.MediaText);
+            Assert.AreEqual("not all", media.Media.MediaText);
+            var list = media.Media;
+            Assert.AreEqual(1, list.Length);
+            Assert.AreEqual(1, media.Rules.Length);
+        }
+
+        [Test]
+        public void OnlyFeatureWidthScreenAndMediaList()
+        {
+            var source = @"@media only screen and (width: 640px) {
+    h1 { color: green }
+}";
+            var sheet = ParseStyleSheet(source);
+            Assert.AreEqual(1, sheet.Rules.Length);
+            Assert.IsInstanceOf<CssMediaRule>(sheet.Rules[0]);
+            var media = (CssMediaRule)sheet.Rules[0];
+            Assert.AreEqual("only screen and (width: 640px)", media.Media.MediaText);
             var list = media.Media;
             Assert.AreEqual(1, list.Length);
             Assert.AreEqual(1, media.Rules.Length);

src/AngleSharp.Css/Dom/Internal/MediaFeature.cs

@@ -1,5 +1,6 @@
-namespace AngleSharp.Css.Dom
+namespace AngleSharp.Css.Dom
 {
+    using AngleSharp.Css.Values;
     using AngleSharp.Text;
     using System;
     using System.IO;
@@ -13,8 +14,9 @@ sealed class MediaFeature : IMediaFeature
 
         private readonly Boolean _min;
         private readonly Boolean _max;
-        private readonly String _name;
+        private readonly ICssValue _name;
         private readonly ICssValue _value;
+        private readonly String _op;
 
         #endregion
 
@@ -26,17 +28,28 @@ internal MediaFeature(String name)
 
         internal MediaFeature(String name, ICssValue value)
         {
-            _name = name;
+            _name = new CssAnyValue(name);
             _value = value;
             _min = name.StartsWith("min-");
             _max = name.StartsWith("max-");
         }
 
+        internal MediaFeature(String name, ICssValue value, String op)
+            : this(new CssAnyValue(name), value, op)
+        {}
+
+        internal MediaFeature(ICssValue name, ICssValue value, String op)
+        {
+            _name = name;
+            _value = value;
+            _op = op;
+        }
+
         #endregion
 
         #region Properties
 
-        public String Name => _name;
+        public String Name => _name?.CssText ?? String.Empty;
 
         public Boolean IsMinimum => _min;
 
@@ -53,9 +66,16 @@ internal MediaFeature(String name, ICssValue value)
         public void ToCss(TextWriter writer, IStyleFormatter formatter)
         {
             writer.Write(Symbols.RoundBracketOpen);
-            writer.Write(_name);
+            writer.Write(Name);
 
-            if (_value != null)
+            if (_op is not null)
+            {
+                writer.Write(" ");
+                writer.Write(_op);
+                writer.Write(" ");
+                writer.Write(Value);
+            }
+            else if (_value is not null)
             {
                 writer.Write(": ");
                 writer.Write(Value);

src/AngleSharp.Css/Extensions/CssValueExtensions.cs

@@ -24,6 +24,10 @@ public static Double AsDouble(this ICssValue value)
             {
                 return fr.Value;
             }
+            else if (value is Ratio ratio)
+            {
+                return ratio.Value;
+            }
             else if (value is ICssMultipleValue multiple && multiple.Count == 1)
             {
                 return multiple[0].AsDouble();

src/AngleSharp.Css/FeatureValidators/AspectRatioFeatureValidator.cs

@@ -11,7 +11,7 @@ public Boolean Validate(IMediaFeature feature, IRenderDevice renderDevice)
         {
             var ratio = RatioConverter.Convert(feature.Value);
 
-            if (ratio != null)
+            if (ratio is not null)
             {
                 var desired = ratio.AsDouble();
                 var available = renderDevice.ViewPortWidth / (Double)renderDevice.ViewPortHeight;

src/AngleSharp.Css/FeatureValidators/DeviceAspectRatioFeatureValidator.cs

@@ -11,7 +11,7 @@ public Boolean Validate(IMediaFeature feature, IRenderDevice renderDevice)
         {
             var ratio = RatioConverter.Convert(feature.Value);
 
-            if (ratio != null)
+            if (ratio is not null)
             {
                 var desired = ratio.AsDouble();
                 var available = renderDevice.DeviceWidth / (Double)renderDevice.DeviceHeight;

src/AngleSharp.Css/Parser/Micro/CalcParser.cs

@@ -141,8 +141,11 @@ private static ICssValue ParseBracketExpression(this StringSource source)
 
             return source.ParseAtomicExpression();
         }
-
-        private static ICssValue ParseAtomicExpression(this StringSource source)
+        
+        /// <summary>
+        /// Parses a unit value into a ICssValue.
+        /// </summary>
+        public static ICssValue ParseAtomicExpression(this StringSource source)
         {
             var unit = source.ParseUnit();
 

src/AngleSharp.Css/Parser/Micro/IdentParser.cs

@@ -48,6 +48,21 @@ public static String ParseIdent(this StringSource source)
             return Start(source, current, buffer);
         }
 
+        /// <summary>
+        /// Parses a CSS identifier value.
+        /// </summary>
+        public static ICssValue ParseIdentAsValue(this StringSource source)
+        {
+            var value = source.ParseIdent();
+
+            if (value is not null)
+            {
+                return new Identifier(value);
+            }
+
+            return null;
+        }
+
         /// <summary>
         /// Parses a CSS constant value from a given dictionary.
         /// </summary>

src/AngleSharp.Css/Parser/Micro/MediaParser.cs

@@ -4,6 +4,8 @@ namespace AngleSharp.Css.Parser
     using AngleSharp.Text;
     using System;
     using System.Collections.Generic;
+    using System.Diagnostics.Tracing;
+    using System.Linq;
 
     /// <summary>
     /// Represents extensions to for media values.
@@ -31,7 +33,20 @@ public static IEnumerable<CssMedium> ParseMedia(this StringSource source, IFeatu
                 {
                     if (current != Symbols.Comma)
                     {
-                        return null;
+                        media[media.Count - 1] = null;
+
+                        while (!source.IsDone && current != Symbols.Comma)
+                        {
+                            if (current == Symbols.RoundBracketOpen)
+                            {
+                                source.Next();
+                                source.TakeUntilClosed();
+                            }
+
+                            current = source.Next();
+                        }
+
+                        continue;
                     }
 
                     source.SkipCurrentAndSpaces();