Fixed issue with longer data URIs #76

Author: FlorianRappl

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

@@ -1,6 +1,8 @@
 namespace AngleSharp.Css.Tests.Declarations
 {
     using AngleSharp.Css.Dom;
+    using AngleSharp.Css.Parser;
+    using AngleSharp.Html.Parser;
     using NUnit.Framework;
     using static CssConstructionFunctions;
 
@@ -689,5 +691,29 @@ public void CssFontStyleNumericWeightSizeFamiliesLegal()
             Assert.IsTrue(property.HasValue);
             Assert.AreEqual("400 12px Georgia, serif", property.Value);
         }
+
+        [Test]
+        public void LongDataUrisShouldNotBeDisappearing_Issue76()
+        {
+            var url = "data-uri.txt".LoadFromResources();
+            var html = $@"<style>@font-face {{
+font-family: ""MyFont"";
+src: url(""{url}"") format('woff');
+font-weight: normal;
+font-style: normal;
+font-display: swap;
+}}</style>";
+
+            var parser = new HtmlParser(new HtmlParserOptions(), BrowsingContext.New(Configuration.Default.WithCss(new CssParserOptions
+            {
+                IsIncludingUnknownDeclarations = true,
+                IsIncludingUnknownRules = true,
+                IsToleratingInvalidSelectors = true,
+            })));
+
+            var dom = parser.ParseDocument(html);
+            var fontFace = ((ICssStyleSheet)dom.StyleSheets[0]).Rules[0] as ICssFontFaceRule;
+            Assert.IsNotEmpty(fontFace.Source);
+        }
     }
 }

src/AngleSharp.Css.Tests/Resources/data-uri.txt

@@ -4,8 +4,11 @@ namespace AngleSharp.Css.Tests
     using AngleSharp.Dom;
     using AngleSharp.Html.Parser;
     using AngleSharp.Io;
+    using AngleSharp.Text;
     using NUnit.Framework;
     using System;
+    using System.IO;
+    using System.Reflection;
 
     static class TestExtensions
     {
@@ -43,5 +46,25 @@ public static IDocument ToHtmlDocument(this String sourceCode, IConfiguration co
             var htmlParser = context.GetService<IHtmlParser>();
             return htmlParser.ParseDocument(sourceCode);
         }
+
+        private static String GetResourceDirectory()
+        {
+            var baseDir = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
+            var path = new DirectoryInfo(baseDir);
+
+            while (!path.Name.Is("AngleSharp.Css.Tests"))
+            {
+                path = path.Parent;
+            }
+
+            return Path.Combine(path.FullName, "Resources");
+        }
+
+        public static String LoadFromResources(this String fileName)
+        {
+            var directory = GetResourceDirectory();
+            var path = Path.Combine(directory, fileName);
+            return File.ReadAllText(path);
+        }
     }
 }

src/AngleSharp.Css.Tests/TestExtensions.cs

@@ -21,7 +21,6 @@ public ICssValue Convert(StringSource source)
 
             while (!source.IsDone)
             {
-                var index = source.Index;
                 var value = _converter.Convert(source);
                 var current = source.SkipSpacesAndComments();
 

src/AngleSharp.Css/Converters/ListValueConverter.cs

@@ -30,6 +30,7 @@ public static CssAttrValue ParseAttr(this StringSource source)
         public static CssReferenceValue ParseVars(this StringSource source)
         {
             var index = source.Index;
+            var start = index;
             var length = FunctionNames.Var.Length;
             var refs = default(List<Tuple<TextRange, CssVarValue>>);
 
@@ -68,6 +69,8 @@ public static CssReferenceValue ParseVars(this StringSource source)
                 break;
             }
 
+            source.BackTo(start);
+
             if (refs != null)
             {
                 return new CssReferenceValue(source.Content, refs);