Fix source position tracking for HTML blocks. Fixes #87

Author: Knagis

CommonMark.NET.nuspec

@@ -2,7 +2,7 @@
 <package xmlns="http://schemas.microsoft.com/packaging/2011/10/nuspec.xsd">
   <metadata>
     <id>CommonMark.NET</id>
-    <version>0.13.2</version>
+    <version>0.13.3</version>
     <title>CommonMark.NET</title>
     <authors>Kārlis Gaņģis</authors>
     <licenseUrl>https://raw.githubusercontent.com/Knagis/CommonMark.NET/master/LICENSE.md</licenseUrl>
@@ -11,7 +11,7 @@
     <requireLicenseAcceptance>false</requireLicenseAcceptance>
     <summary>Fastest .NET library for converting Markdown documents to HTML.</summary>
     <description>.NET library for converting Markdown documents to HTML according to the CommonMark specification. Optimized for maximum performance and targets every .NET version since 2.0, including PCL, Mono and .NET Core.</description>
-    <releaseNotes>Fix unhandled exception.</releaseNotes>
+    <releaseNotes>Improves source position tracking for HTML blocks.</releaseNotes>
     <copyright>Copyright © Kārlis Gaņģis 2014-2016</copyright>
     <tags>CommonMark Markdown</tags>
   </metadata>

CommonMark.NETCore/project.json

@@ -1,5 +1,5 @@
 {
-  "version": "0.13.2",
+  "version": "0.13.3",
   "frameworks": {
     "dnxcore50": {
       "compilationOptions": {

CommonMark.Tests/SourcePositionTests.cs

@@ -655,5 +655,65 @@ public void SourcePositionRemovingReferences()
             Assert.IsNotNull(inline);
             Assert.AreEqual("*asd*", data.Substring(inline.Inline.SourcePosition, inline.Inline.SourceLength));
         }
+
+        [TestMethod]
+        [TestCategory("SourcePosition - HTML Blocks")]
+        public void SourcePositionHtmlBlock1()
+        {
+            var data = "<pre>\n</pre>\nfoo";
+            var doc = Helpers.ParseDocument(data, Settings);
+
+            var block = doc.AsEnumerable()
+                .FirstOrDefault(o => o.Block != null && o.Block.Tag == Syntax.BlockTag.HtmlBlock);
+
+            Assert.IsNotNull(block);
+            Assert.AreEqual("<pre>\n</pre>\n",
+                data.Substring(block.Block.SourcePosition, block.Block.SourceLength));
+        }
+
+        [TestMethod]
+        [TestCategory("SourcePosition - HTML Blocks")]
+        public void SourcePositionHtmlBlock2()
+        {
+            var data = "<!--\n-->\nfoo";
+            var doc = Helpers.ParseDocument(data, Settings);
+
+            var block = doc.AsEnumerable()
+                .FirstOrDefault(o => o.Block != null && o.Block.Tag == Syntax.BlockTag.HtmlBlock);
+
+            Assert.IsNotNull(block);
+            Assert.AreEqual("<!--\n-->\n",
+                data.Substring(block.Block.SourcePosition, block.Block.SourceLength));
+        }
+
+        [TestMethod]
+        [TestCategory("SourcePosition - HTML Blocks")]
+        public void SourcePositionHtmlBlock6()
+        {
+            var data = "<div id='foo'>\r\nbar\r\n</div>\r\n\r\n";
+            var doc = Helpers.ParseDocument(data, Settings);
+
+            var block = doc.AsEnumerable()
+                .FirstOrDefault(o => o.Block != null && o.Block.Tag == Syntax.BlockTag.HtmlBlock);
+
+            Assert.IsNotNull(block);
+            Assert.AreEqual("<div id='foo'>\r\nbar\r\n</div>\r\n",
+                data.Substring(block.Block.SourcePosition, block.Block.SourceLength));
+        }
+
+        [TestMethod]
+        [TestCategory("SourcePosition - HTML Blocks")]
+        public void SourcePositionHtmlBlock7()
+        {
+            var data = "<fooobar>\r\nbar\r\n\r\nbar";
+            var doc = Helpers.ParseDocument(data, Settings);
+
+            var block = doc.AsEnumerable()
+                .FirstOrDefault(o => o.Block != null && o.Block.Tag == Syntax.BlockTag.HtmlBlock);
+
+            Assert.IsNotNull(block);
+            Assert.AreEqual("<fooobar>\r\nbar\r\n",
+                data.Substring(block.Block.SourcePosition, block.Block.SourceLength));
+        }
     }
 }

CommonMark/Parser/BlockMethods.cs

@@ -111,8 +111,14 @@ public static void Finalize(Block b, LineInfo line)
 
             if (line.IsTrackingPositions)
             {
+                // HTML Blocks other than type 7 call Finalize when the last line is encountered.
+                // Block types 6 and 7 calls Finalize once it finds the next empty row but that empty row is no longer considered to be part of the block.
+                var includesThisLine = b.HtmlBlockType != HtmlBlockType.None && b.HtmlBlockType != HtmlBlockType.InterruptingBlock && b.HtmlBlockType != HtmlBlockType.NonInterruptingBlock;
+
                 // (b.SourcePosition >= line.LineOffset) determines if the block started on this line.
-                if (b.SourcePosition >= line.LineOffset && line.Line != null)
+                includesThisLine = includesThisLine || b.SourcePosition >= line.LineOffset && line.Line != null;
+
+                if (includesThisLine)
                     b.SourceLastPosition = line.CalculateOrigin(line.Line.Length, false);
                 else
                     b.SourceLastPosition = line.CalculateOrigin(0, false);