[stable/20240723] [clang][ExtractAPI] combine typedef records if the underlying type's name is underscored

clang/include/clang/ExtractAPI/ExtractAPIVisitor.h

@@ -1146,11 +1146,29 @@ bool ExtractAPIVisitorBase<Derived>::VisitTypedefNameDecl(
 
   StringRef Name = Decl->getName();
 
+  auto nameMatches = [&Name](TagDecl *TagDecl) {
+    StringRef TagName = TagDecl->getName();
+
+    if (TagName == Name)
+      return true;
+
+    // Also check whether the tag decl's name is the same as the typedef name
+    // with prefixed underscores
+    if (TagName.starts_with('_')) {
+      StringRef StrippedName = TagName.ltrim('_');
+
+      if (StrippedName == Name)
+        return true;
+    }
+
+    return false;
+  };
+
   // If the underlying type was defined as part of the typedef modify it's
   // fragments directly and pretend the typedef doesn't exist.
   if (auto *TagDecl = Decl->getUnderlyingType()->getAsTagDecl()) {
     if (TagDecl->isEmbeddedInDeclarator() && TagDecl->isCompleteDefinition() &&
-        Decl->getName() == TagDecl->getName()) {
+        nameMatches(TagDecl)) {
       SmallString<128> TagUSR;
       index::generateUSRForDecl(TagDecl, TagUSR);
       if (auto *Record = API.findRecordForUSR(TagUSR)) {
@@ -1164,6 +1182,11 @@ bool ExtractAPIVisitorBase<Derived>::VisitTypedefNameDecl(
             .append(Name, DeclarationFragments::FragmentKind::Identifier)
             .appendSemicolon();
 
+        // Replace the name and subheading in case it's underscored so we can
+        // use the non-underscored version
+        Record->Name = Name;
+        Record->SubHeading = DeclarationFragmentsBuilder::getSubHeading(Decl);
+
         return true;
       }
     }

clang/test/ExtractAPI/typedef_underscore.c

@@ -0,0 +1,69 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -extract-api --pretty-sgf --emit-sgf-symbol-labels-for-testing \
+// RUN:   --product-name=TypedefChain -triple arm64-apple-macosx -x c-header %s -o %t/typedefchain-c.symbols.json -verify
+// RUN: %clang_cc1 -extract-api --pretty-sgf --emit-sgf-symbol-labels-for-testing \
+// RUN:   --product-name=TypedefChain -triple arm64-apple-macosx -x c++-header %s -o %t/typedefchain-cxx.symbols.json -verify
+
+// RUN: FileCheck %s --input-file %t/typedefchain-c.symbols.json --check-prefix MYSTRUCT
+// RUN: FileCheck %s --input-file %t/typedefchain-cxx.symbols.json --check-prefix MYSTRUCT
+typedef struct _MyStruct { } MyStruct;
+
+// MYSTRUCT-LABEL: "!testLabel": "c:@S@_MyStruct"
+// MYSTRUCT:      "accessLevel": "public",
+// MYSTRUCT:      "declarationFragments": [
+// MYSTRUCT-NEXT:   {
+// MYSTRUCT-NEXT:     "kind": "keyword",
+// MYSTRUCT-NEXT:     "spelling": "typedef"
+// MYSTRUCT-NEXT:   },
+// MYSTRUCT-NEXT:   {
+// MYSTRUCT-NEXT:     "kind": "text",
+// MYSTRUCT-NEXT:     "spelling": " "
+// MYSTRUCT-NEXT:   },
+// MYSTRUCT-NEXT:   {
+// MYSTRUCT-NEXT:     "kind": "keyword",
+// MYSTRUCT-NEXT:     "spelling": "struct"
+// MYSTRUCT-NEXT:   },
+// MYSTRUCT-NEXT:   {
+// MYSTRUCT-NEXT:     "kind": "text",
+// MYSTRUCT-NEXT:     "spelling": " "
+// MYSTRUCT-NEXT:   },
+// MYSTRUCT-NEXT:   {
+// MYSTRUCT-NEXT:     "kind": "identifier",
+// MYSTRUCT-NEXT:     "spelling": "_MyStruct"
+// MYSTRUCT-NEXT:   },
+// MYSTRUCT-NEXT:   {
+// MYSTRUCT-NEXT:     "kind": "text",
+// MYSTRUCT-NEXT:     "spelling": " { ... } "
+// MYSTRUCT-NEXT:   },
+// MYSTRUCT-NEXT:   {
+// MYSTRUCT-NEXT:     "kind": "identifier",
+// MYSTRUCT-NEXT:     "spelling": "MyStruct"
+// MYSTRUCT-NEXT:   },
+// MYSTRUCT-NEXT:   {
+// MYSTRUCT-NEXT:     "kind": "text",
+// MYSTRUCT-NEXT:     "spelling": ";"
+// MYSTRUCT-NEXT:   }
+// MYSTRUCT-NEXT: ],
+// MYSTRUCT:      "kind": {
+// MYSTRUCT-NEXT:   "displayName": "Structure",
+// MYSTRUCT-NEXT:   "identifier": "c{{(\+\+)?}}.struct"
+// MYSTRUCT:           "names": {
+// MYSTRUCT-NEXT:        "navigator": [
+// MYSTRUCT-NEXT:          {
+// MYSTRUCT-NEXT:            "kind": "identifier",
+// MYSTRUCT-NEXT:            "spelling": "MyStruct"
+// MYSTRUCT-NEXT:          }
+// MYSTRUCT-NEXT:        ],
+// MYSTRUCT-NEXT:        "subHeading": [
+// MYSTRUCT-NEXT:          {
+// MYSTRUCT-NEXT:            "kind": "identifier",
+// MYSTRUCT-NEXT:            "spelling": "MyStruct"
+// MYSTRUCT-NEXT:          }
+// MYSTRUCT-NEXT:        ],
+// MYSTRUCT-NEXT:        "title": "MyStruct"
+// MYSTRUCT-NEXT:      },
+// MYSTRUCT:      "pathComponents": [
+// MYSTRUCT-NEXT:    "MyStruct"
+// MYSTRUCT-NEXT:  ]
+
+// expected-no-diagnostics