Fixed parsing of background none #65

Author: FlorianRappl

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

@@ -613,6 +613,30 @@ public void CssBackgroundRedLegal()
             Assert.AreEqual("rgba(255, 0, 0, 1)", property.Value);
         }
 
+        [Test]
+        public void CssBackgroundNoneLegal()
+        {
+            var snippet = "background: none";
+            var property = ParseDeclaration(snippet);
+            Assert.AreEqual("background", property.Name);
+            Assert.IsFalse(property.IsImportant);
+            Assert.IsFalse(property.IsInherited);
+            Assert.IsTrue(property.HasValue);
+            Assert.AreEqual("none", property.Value);
+        }
+
+        [Test]
+        public void CssBackgroundNoneColoredLegal()
+        {
+            var snippet = "background: none rgb(1, 2, 3)";
+            var property = ParseDeclaration(snippet);
+            Assert.AreEqual("background", property.Name);
+            Assert.IsFalse(property.IsImportant);
+            Assert.IsFalse(property.IsInherited);
+            Assert.IsTrue(property.HasValue);
+            Assert.AreEqual("none rgba(1, 2, 3, 1)", property.Value);
+        }
+
         [Test]
         public void CssBackgroundWhiteImageLegal()
         {

src/AngleSharp.Css/Declarations/BackgroundDeclaration.cs

@@ -34,6 +34,56 @@ sealed class BackgroundAggregator : IValueAggregator, IValueConverter
         {
             public ICssValue Convert(StringSource source)
             {
+                // [ <bg-layer> , ]* <final-bg-layer>
+                // where:
+                //   <bg-layer> = <bg-image> || <bg-position> [ / <bg-size> ]? || <repeat-style> || <attachment> || <box> || <box>
+                //   <final-bg-layer> = <'background-color'> || <bg-image> || <bg-position> [ / <bg-size> ]? || <repeat-style> || <attachment> || <box> || <box>
+                // where:
+                //   <bg-image> = none | <image>
+                //   <bg-position> = [ [ left | center | right | top | bottom | <length-percentage> ] | [ left | center | right | <length-percentage> ] [ top | center | bottom | <length-percentage> ] | [ center | [ left | right ] <length-percentage>? ] && [ center | [ top | bottom ] <length-percentage>? ] ]
+                //   <bg-size> = [ <length-percentage> | auto ]{1,2} | cover | contain
+                //   <repeat-style> = repeat-x | repeat-y | [ repeat | space | round | no-repeat ]{1,2}
+                //   <attachment> = scroll | fixed | local
+                //   <box> = border-box | padding-box | content-box
+                //   <image> = <url> | <image()> | <image-set()> | <element()> | <paint()> | <cross-fade()> | <gradient>
+                //   <length-percentage> = <length> | <percentage>
+                //   <image()> = image( <image-tags>? [ <image-src>? , <color>? ]! )
+                //   <image-set()> = image-set( <image-set-option># )
+                //   <element()> = element( <id-selector> )
+                //   <paint()> = paint( <ident>, <declaration-value>? )
+                //   <cross-fade()> = cross-fade( <cf-mixing-image> , <cf-final-image>? )
+                //   <gradient> = <linear-gradient()> | <repeating-linear-gradient()> | <radial-gradient()> | <repeating-radial-gradient()> | <conic-gradient()>
+                //   <image-tags> = ltr | rtl
+                //   <image-src> = <url> | <string>
+                //   <color> = <rgb()> | <rgba()> | <hsl()> | <hsla()> | <hex-color> | <named-color> | currentcolor | <deprecated-system-color>
+                //   <image-set-option> = [ <image> | <string> ] <resolution>
+                //   <id-selector> = <hash-token>
+                //   <cf-mixing-image> = <percentage>? && <image>
+                //   <cf-final-image> = <image> | <color>
+                //   <linear-gradient()> = linear-gradient( [ <angle> | to <side-or-corner> ]? , <color-stop-list> )
+                //   <repeating-linear-gradient()> = repeating-linear-gradient( [ <angle> | to <side-or-corner> ]? , <color-stop-list> )
+                //   <radial-gradient()> = radial-gradient( [ <ending-shape> || <size> ]? [ at <position> ]? , <color-stop-list> )
+                //   <repeating-radial-gradient()> = repeating-radial-gradient( [ <ending-shape> || <size> ]? [ at <position> ]? , <color-stop-list> )
+                //   <conic-gradient()> = conic-gradient( [ from <angle> ]? [ at <position> ]?, <angular-color-stop-list> )
+                //   <rgb()> = rgb( <percentage>{3} [ / <alpha-value> ]? ) | rgb( <number>{3} [ / <alpha-value> ]? ) | rgb( <percentage>#{3} , <alpha-value>? ) | rgb( <number>#{3} , <alpha-value>? )
+                //   <rgba()> = rgba( <percentage>{3} [ / <alpha-value> ]? ) | rgba( <number>{3} [ / <alpha-value> ]? ) | rgba( <percentage>#{3} , <alpha-value>? ) | rgba( <number>#{3} , <alpha-value>? )
+                //   <hsl()> = hsl( <hue> <percentage> <percentage> [ / <alpha-value> ]? ) | hsl( <hue>, <percentage>, <percentage>, <alpha-value>? )
+                //   <hsla()> = hsla( <hue> <percentage> <percentage> [ / <alpha-value> ]? ) | hsla( <hue>, <percentage>, <percentage>, <alpha-value>? )
+                //   <side-or-corner> = [ left | right ] || [ top | bottom ]
+                //   <color-stop-list> = [ <linear-color-stop> [, <linear-color-hint>]? ]# , <linear-color-stop>
+                //   <ending-shape> = circle | ellipse
+                //   <size> = closest-side | farthest-side | closest-corner | farthest-corner | <length> | <length-percentage>{2}
+                //   <position> = [ [ left | center | right ] || [ top | center | bottom ] | [ left | center | right | <length-percentage> ] [ top | center | bottom | <length-percentage> ]? | [ [ left | right ] <length-percentage> ] && [ [ top | bottom ] <length-percentage> ] ]
+                //   <angular-color-stop-list> = [ <angular-color-stop> [, <angular-color-hint>]? ]# , <angular-color-stop>
+                //   <alpha-value> = <number> | <percentage>
+                //   <hue> = <number> | <angle>
+                //   <linear-color-stop> = <color> <color-stop-length>?
+                //   <linear-color-hint> = <length-percentage>
+                //   <angular-color-stop> = <color> && <color-stop-angle>?
+                //   <angular-color-hint> = <angle-percentage>
+                //   <color-stop-length> = <length-percentage>{1,2}
+                //   <color-stop-angle> = <angle-percentage>{1,2}
+                //   <angle-percentage> = <angle> | <percentage>
                 var layers = new List<CssBackgroundLayerValue>();
                 var color = default(ICssValue);
                 var pos = 0;
@@ -65,7 +115,7 @@ public ICssValue Convert(StringSource source)
 
                         if (image == null)
                         {
-                            image = source.ParseImageSource();
+                            image = source.ParseImageSource() ?? (source.IsIdentifier(CssKeywords.None) ? new CssNoneValue() : null);
                             c = source.SkipSpacesAndComments();
                         }
 

src/AngleSharp.Css/Values/Functions/CssNoneValue.cs

@@ -0,0 +1,14 @@
+namespace AngleSharp.Css.Values
+{
+    using AngleSharp.Css.Dom;
+    using System;
+
+    sealed class CssNoneValue : ICssImageValue
+    {
+        public String Name => CssKeywords.None;
+
+        public ICssValue[] Arguments => Array.Empty<ICssValue>();
+
+        public String CssText => CssKeywords.None;
+    }
+}