Include Mentioned In links in the HTML content

Author: d-ronnqvist

Sources/SwiftDocC/Model/Rendering/HTML/HTMLRenderer.swift

@@ -445,6 +445,21 @@ struct HTMLRenderer {
             articleElement.addChild(.element(named: "hr")) // Separate the sections with a thematic break
         }
 
+        if FeatureFlags.current.isMentionedInEnabled {
+            separateCurationIfNeeded()
+            
+            let mentions = context.articleSymbolMentions.articlesMentioning(reference)
+            if !mentions.isEmpty {
+                articleElement.addChild(
+                    renderer.selfReferencingSection(named: "Mentioned In", content: [
+                        .element(named: "ul", children: mentions.compactMap { reference in
+                            context.documentationCache[reference].map { .element(named: "li", children: [.text($0.name.description)]) }
+                        })
+                    ])
+                )
+            }
+        }
+        
         // Discussion
         if let discussion = symbol.discussion {
             separateCurationIfNeeded()

Tests/SwiftDocCUtilitiesTests/FileWritingHTMLContentConsumerTests.swift

@@ -27,7 +27,7 @@ final class FileWritingHTMLContentConsumerTests: XCTestCase {
             
             ## Custom discussion
             
-            It explains how a developer can perform some task using this module.
+            It explains how a developer can perform some task using ``SomeClass`` in this module.
             
             ### Details
             
@@ -254,6 +254,12 @@ final class FileWritingHTMLContentConsumerTests: XCTestCase {
                 <code>class SomeClass</code>
             </pre>
         </section>
+        <section>
+            <h2>Mentioned In</h2>
+            <ul>
+                <li>Some article</li>
+            </ul>
+        </section>
         <section>
             <h2>Topics</h2>
             <h3>Instance Methods</h3>
@@ -369,7 +375,10 @@ final class FileWritingHTMLContentConsumerTests: XCTestCase {
         </section>
         <section>
             <h2>Custom discussion</h2>
-            <p>It explains how a developer can perform some task using this module.</p>
+            <p>It explains how a developer can perform some task using <a href="../SomeClass/index.html">
+                    <code>SomeClass</code>
+                </a>
+                 in this module.</p>
             <h3>Details</h3>
             <p>This subsection describes something more detailed.</p>
         </section>