Defensive code on empty bookmark

Author: onizet

src/Html2OpenXml/Expressions/BodyExpression.cs

@@ -105,7 +105,7 @@ private void MarkAllBookmarks()
         var links = node.QuerySelectorAll("a[href^='#']");
         if (links.Length == 0) return;
 
-        foreach (var link in links.Cast<IHtmlAnchorElement>())
+        foreach (var link in links.Cast<IHtmlAnchorElement>().Where(l => l.Hash.Length > 0))
         {
             var id = link.Hash.Substring(1);
             var target = node.Owner!.GetElementById(id);

test/HtmlToOpenXml.Tests/LinkTests.cs

@@ -38,6 +38,8 @@ public void ExternalLink_ShouldSucceed (string link)
 
         [TestCase(@"<a href=""javascript:alert()"">Js</a>")]
         [TestCase(@"<a href=""site.com"">Unknown site</a>")]
+        [TestCase(@"<a href=''>Empty link</a>")]
+        [TestCase(@"<a href='#'>Empty bookmark</a>")]
         public void InvalidLink_ReturnsSimpleRun (string html)
         {
             // invalid link leads to simple Run with no link