fix: Doc comment <code> block is not rendered correctly (#10390)

* fix: code block is not rendered correctly

* test(snapshot): update snapshots

test(snapshot): update snapshots e1b692a

* test(snapshot): update snapshots 887b6b6

---------

Co-authored-by: filzrev <[email protected]>

Author: filzrev

samples/seed/dotnet/project/Project/Inheritdoc.cs

@@ -108,4 +108,41 @@ public class Class2 : Class1<bool>
             public override bool TestMethod1(bool parm1, int parm2) => false;
         }
     }
-}
+
+    // Issue #9736 #9495 #9754
+    public class Issue9736
+    {
+        public interface IJsonApiOptions
+        {
+            /// <summary>
+            /// Whether to use relative links for all resources. <c>false</c> by default.
+            /// </summary>
+            /// <example>
+            /// <code><![CDATA[
+            /// options.UseRelativeLinks = true;
+            /// ]]></code>
+            /// <code><![CDATA[
+            /// {
+            ///   "type": "articles",
+            ///   "id": "4309",
+            ///   "relationships": {
+            ///      "author": {
+            ///        "links": {
+            ///          "self": "/api/shopping/articles/4309/relationships/author",
+            ///          "related": "/api/shopping/articles/4309/author"
+            ///        }
+            ///      }
+            ///   }
+            /// }
+            /// ]]></code>
+            /// </example>
+            bool UseRelativeLinks { get; }
+        }
+
+        public sealed class JsonApiOptions : IJsonApiOptions
+        {
+            /// <inheritdoc />
+            public bool UseRelativeLinks { get; set; }
+        }
+    }
+}

src/Docfx.Dotnet/Parsers/XmlComment.cs

@@ -124,10 +124,6 @@ public static XmlComment Parse(string xml, XmlCommentParserContext context = nul
         }
         try
         {
-            // Format xml with indentation.
-            // It's needed to fix issue (https://github.com/dotnet/docfx/issues/9736)
-            xml = XElement.Parse(xml).ToString(SaveOptions.None);
-
             return new XmlComment(xml, context ?? new());
         }
         catch (XmlException)
@@ -173,7 +169,8 @@ private void ResolveCode(XDocument doc, XmlCommentParserContext context)
 
             code.SetAttributeValue("class", $"lang-{lang}");
 
-            if (node.PreviousNode is null)
+            if (node.PreviousNode is null
+             || node.PreviousNode is XText xText && xText.Value == $"\n{indent}")
             {
                 // Xml writer formats <pre><code> with unintended identation
                 // when there is no preceeding text node.

test/Docfx.Dotnet.Tests/XmlCommentUnitTest.cs

@@ -28,7 +28,8 @@ public static void ParaNewLine()
         Assert.Equal(
             """
             a
-            <p>b</p><p>c</p>
+            <p>b</p>
+            <p>c</p>
             """,
             XmlComment.Parse("""
                 <summary>
@@ -390,13 +391,14 @@ Classes in assemblies are by definition complete.
             <a href="https://example.org">example</a>
             <p>This is <code class="paramref">ref</code> a sample of exception node</p>
             <ul><li>
-                  <pre><code class="lang-c#">public class XmlElement
-                      : XmlLinkedNode</code></pre>
-                  <ol><li>
-                                    word inside list-&gt;listItem-&gt;list-&gt;listItem-&gt;para.&gt;
+
+                        <pre><code class="lang-c#">public class XmlElement
+                            : XmlLinkedNode</code></pre>
+                        <ol><li>
+                                    word inside list->listItem->list->listItem->para.>
                                     the second line.
                                 </li><li>item2 in numbered list</li></ol>
-                </li><li>item2 in bullet list</li><li>
+                    </li><li>item2 in bullet list</li><li>
                     loose text <i>not</i> wrapped in description
                 </li></ul>
             """, remarks, ignoreLineEndingDifferences: true);
@@ -519,6 +521,7 @@ public void Issue9495()
         Assert.Equal(
             """
             <pre><code class="lang-csharp">options.UseRelativeLinks = true;</code></pre>
+
             <pre><code class="lang-csharp">{
               "type": "articles",
               "id": "4309",
@@ -533,4 +536,45 @@ public void Issue9495()
             }</code></pre>
             """, comment.Examples[0], ignoreLineEndingDifferences: true);
     }
+
+    [Fact]
+    public void Issue10385()
+    {
+        var comment = XmlComment.Parse(
+            """
+            <remarks>
+            <para>
+            Paragraph.
+            </para>
+            <code lang="cs">
+            public sealed class Issue10385
+            {
+                public int AAA {get;set;}
+            
+                public int BBB {get;set;}
+            
+                public int CCC {get;set;}
+            }
+            </code>
+            </remarks>
+            """);
+        Assert.Equal(
+            """
+            <p>
+            Paragraph.
+            </p>
+
+            <pre><code class="lang-csharp">public sealed class Issue10385
+            {
+                public int AAA {get;set;}
+
+                public int BBB {get;set;}
+
+                public int CCC {get;set;}
+            }</code></pre>
+            """, comment.Remarks, ignoreLineEndingDifferences: true);
+    }
+
+
+
 }