Refined initial value handling

Author: FlorianRappl

src/AngleSharp.Css.Tests/Styling/CssSheet.cs

@@ -142,12 +142,11 @@ public void CssSheetCloseStringsEndOfLine()
             Assert.AreEqual(1, sheet.Rules.Length);
             Assert.IsInstanceOf<CssStyleRule>(sheet.Rules[0]);
             var p = sheet.Rules[0] as ICssStyleRule;
-            Assert.AreEqual(2, p.Style.Length);
+            Assert.AreEqual(1, p.Style.Length);
             Assert.AreEqual("p", p.SelectorText);
             Assert.AreEqual("color", p.Style[0]);
-            Assert.AreEqual("font-family", p.Style[1]);
             Assert.AreEqual("rgba(0, 128, 0, 1)", p.Style.GetColor());
-            Assert.AreEqual("initial", p.Style.GetFontFamily());
+            Assert.AreEqual("", p.Style.GetFontFamily());
         }
 
         [Test]
@@ -304,8 +303,8 @@ public void CssSheetIgnoreInvalidValueFloat()
             Assert.IsInstanceOf<CssStyleRule>(sheet.Rules[0]);
             var img = sheet.Rules[0] as ICssStyleRule;
             Assert.AreEqual("img", img.SelectorText);
-            Assert.AreEqual(1, img.Style.Length);
-            Assert.AreEqual("initial", img.Style.GetFloat());
+            Assert.AreEqual(0, img.Style.Length);
+            Assert.AreEqual("", img.Style.GetFloat());
         }
 
         [Test]

src/AngleSharp.Css.Tests/Styling/HtmlCssIntegration.cs

@@ -61,8 +61,8 @@ public void ParsedCssCanHaveExtraWhitespace()
                 IsIncludingUnknownRules = true
             });
             var div = doc.QuerySelector<IHtmlElement>("div");
-            Assert.AreEqual("initial", div.GetStyle()["background-color"]);
-            Assert.AreEqual("background-color: initial", div.GetStyle().CssText);
+            Assert.AreEqual("", div.GetStyle()["background-color"]);
+            Assert.AreEqual("", div.GetStyle().CssText);
         }
 
         [Test]
@@ -326,7 +326,7 @@ public void SetStyleAttributeAfterPageLoadWithInvalidColor()
             // hang occurs only if this line is executed prior to setting the attribute
             // hang occurs when executing next line
             div.SetAttribute("style", "background-color: http://www.codeplex.com?url=&lt;SCRIPT&gt;a=/XSS/alert(a.source)&lt;/SCRIPT&gt;");
-            Assert.AreEqual("initial", div.GetStyle().GetBackgroundColor());
+            Assert.AreEqual("", div.GetStyle().GetBackgroundColor());
         }
 
         [Test]

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

@@ -46,7 +46,7 @@ public ICssValue RawValue
 
         public String Value
         {
-            get => _value?.CssText ?? CssKeywords.Initial;
+            get => _value?.CssText ?? String.Empty;
             set => _value = _converter.Convert(value);
         }
 

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

@@ -100,34 +100,40 @@ public void Update(String value)
 
         private ICssProperty TryCreateShorthand(String shorthandName, IEnumerable<String> serialized, List<String> usedProperties, Boolean force)
         {
-            var longhands = Declarations.Where(m => !serialized.Contains(m.Name)).ToList();
             var factory = _context.GetFactory<IDeclarationFactory>();
             var shorthand = factory.Create(shorthandName);
             var requiredProperties = shorthand.Longhands;
-            var values = new ICssValue[requiredProperties.Length];
-            var important = 0;
-            var count = 0;
 
-            for (var i = 0; i < values.Length; i++)
+            if (requiredProperties.Length > 0)
             {
-                var name = requiredProperties[i];
-                var propInfo = factory.Create(name);
-                var property = propInfo.Longhands.Any() ?
-                    TryCreateShorthand(name, serialized, usedProperties, force) :
-                    longhands.Where(m => m.Name == name).FirstOrDefault();
+                var longhands = Declarations.Where(m => !serialized.Contains(m.Name)).ToList();
+                var values = new ICssValue[requiredProperties.Length];
+                var important = 0;
+                var count = 0;
 
-                if (property != null)
+                for (var i = 0; i < values.Length; i++)
                 {
-                    usedProperties.Add(name);
-                    count = count + 1;
-                    important = important + (property.IsImportant ? 1 : 0);
-                    values[i] = property.RawValue;
+                    var name = requiredProperties[i];
+                    var propInfo = factory.Create(name);
+                    var property = propInfo.Longhands.Any() ?
+                        TryCreateShorthand(name, serialized, usedProperties, force) :
+                        longhands.Where(m => m.Name == name).FirstOrDefault();
+
+                    if (property != null)
+                    {
+                        usedProperties.Add(name);
+                        count = count + 1;
+                        important = important + (property.IsImportant ? 1 : 0);
+                        values[i] = property.RawValue;
+                    }
                 }
+
+                var valid = count == values.Length && (important == 0 || important == count);
+                var result = force || valid ? _context.CreateShorthand(shorthandName, values, important != 0) : null;
+                return force || result?.RawValue != null ? result : null;
             }
 
-            var valid = count == values.Length && (important == 0 || important == count);
-            var result = force || valid ? _context.CreateShorthand(shorthandName, values, important != 0) : null;
-            return force || result?.RawValue != null ? result : null;
+            return _context.CreateProperty(shorthandName);
         }
 
         public String ToCssBlock(IStyleFormatter formatter)
@@ -264,9 +270,13 @@ public void SetProperty(String propertyName, String propertyValue, String priori
                     if (property != null)
                     {
                         property.Value = propertyValue;
-                        property.IsImportant = priority != null;
-                        SetProperty(property);
-                        RaiseChanged();
+
+                        if (property.RawValue != null)
+                        {
+                            property.IsImportant = priority != null;
+                            SetProperty(property);
+                            RaiseChanged();
+                        }
                     }
                 }
             }

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

@@ -32,10 +32,8 @@ static class ColorParser
             return result;
         }
 
-        public static Color? ParseCurrentColor(this StringSource source)
-        {
-            return source.IsIdentifier(CssKeywords.CurrentColor) ? Color.CurrentColor : ColorParser.ParseColor(source);
-        }
+        public static Color? ParseCurrentColor(this StringSource source) =>
+            source.IsIdentifier(CssKeywords.CurrentColor) ? Color.CurrentColor : ColorParser.ParseColor(source);
 
         private static Color? Start(StringSource source)
         {