[clang-tools-extra] [clang-doc] Add a Mustache Markdown generator (PR #177221)

[Erick Velez via cfe-commits]

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@@ -419,12 +421,25 @@ static void serializeReference(const Reference &Ref, Object &ReferenceObj) {
   }
 }
 
+static void serializeMDReference(const Reference &Ref, Object &ReferenceObj,
+                                 StringRef BasePath) {
+  serializeReference(Ref, ReferenceObj);
+  SmallString<64> Path = Ref.getRelativeFilePath(BasePath);
+  sys::path::native(Path, sys::path::Style::posix);
+  sys::path::append(Path, sys::path::Style::posix,
+                    Ref.getFileBaseName() + ".md");
+  ReferenceObj["BasePath"] = Path;
+}
+
+typedef std::function<void(const Reference &, Object &)> ReferenceFunc;
+
 // Although namespaces and records both have ScopeChildren, they serialize them
 // differently. Only enums, records, and typedefs are handled here.
-static void
-serializeCommonChildren(const ScopeChildren &Children, json::Object &Obj,
-                        const std::optional<StringRef> RepositoryUrl,
-                        const std::optional<StringRef> RepositoryLinePrefix) {
+static void serializeCommonChildren(
+    const ScopeChildren &Children, json::Object &Obj,
+    const std::optional<StringRef> RepositoryUrl,
+    const std::optional<StringRef> RepositoryLinePrefix,
+    std::optional<ReferenceFunc> MDReferenceLambda = std::nullopt) {
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evelez7 wrote:

This is kind of complicated since the lambda needs to capture a variable specific to Markdown documentation, so it can't just be local or else we'd need to pass that variable here too.

https://github.com/llvm/llvm-project/pull/177221