[clang][ExtractAPI] Flatten children of nested anonymous records into the parent scope

When an anonymous record is nested within another record and is not
attached to a variable's type, we migrate the children to the parent
record.

rdar://128092236

Author: daniel-grumberg

clang/include/clang/ExtractAPI/ExtractAPIVisitor.h

@@ -38,6 +38,8 @@ namespace impl {
 
 template <typename Derived>
 class ExtractAPIVisitorBase : public RecursiveASTVisitor<Derived> {
+  using Base = RecursiveASTVisitor<Derived>;
+
 protected:
   ExtractAPIVisitorBase(ASTContext &Context, APISet &API)
       : Context(Context), API(API) {}
@@ -79,8 +81,10 @@ class ExtractAPIVisitorBase : public RecursiveASTVisitor<Derived> {
 
   bool VisitNamespaceDecl(const NamespaceDecl *Decl);
 
+  bool TraverseRecordDecl(RecordDecl *Decl);
   bool VisitRecordDecl(const RecordDecl *Decl);
 
+  bool TraverseCXXRecordDecl(CXXRecordDecl *Decl);
   bool VisitCXXRecordDecl(const CXXRecordDecl *Decl);
 
   bool VisitCXXMethodDecl(const CXXMethodDecl *Decl);
@@ -548,6 +552,19 @@ bool ExtractAPIVisitorBase<Derived>::VisitNamespaceDecl(
   return true;
 }
 
+template <typename Derived>
+bool ExtractAPIVisitorBase<Derived>::TraverseRecordDecl(RecordDecl *Decl) {
+  bool Ret = Base::TraverseRecordDecl(Decl);
+
+  if (!isEmbeddedInVarDeclarator(*Decl) && Decl->isAnonymousStructOrUnion()) {
+    SmallString<128> USR;
+    index::generateUSRForDecl(Decl, USR);
+    API.removeRecord(USR);
+  }
+
+  return Ret;
+}
+
 template <typename Derived>
 bool ExtractAPIVisitorBase<Derived>::VisitRecordDecl(const RecordDecl *Decl) {
   if (!getDerivedExtractAPIVisitor().shouldDeclBeIncluded(Decl))
@@ -588,6 +605,19 @@ bool ExtractAPIVisitorBase<Derived>::VisitRecordDecl(const RecordDecl *Decl) {
   return true;
 }
 
+template <typename Derived>
+bool ExtractAPIVisitorBase<Derived>::TraverseCXXRecordDecl(CXXRecordDecl *Decl) {
+  bool Ret = Base::TraverseCXXRecordDecl(Decl);
+
+  if (!isEmbeddedInVarDeclarator(*Decl) && Decl->isAnonymousStructOrUnion()) {
+    SmallString<128> USR;
+    index::generateUSRForDecl(Decl, USR);
+    API.removeRecord(USR);
+  }
+
+  return Ret;
+}
+
 template <typename Derived>
 bool ExtractAPIVisitorBase<Derived>::VisitCXXRecordDecl(
     const CXXRecordDecl *Decl) {

clang/test/ExtractAPI/anonymous_record_no_typedef.c

@@ -163,4 +163,16 @@ enum {
 // GLOBALOTHERCASE-NEXT:   "GlobalOtherCase"
 // GLOBALOTHERCASE-NEXT: ]
 
+// RUN: FileCheck %s --input-file %t/output.symbols.json --check-prefix VEC
+union Vector {
+  struct {
+    float X;
+    float Y;
+  };
+  float Data[2];
+};
+// VEC-DAG: "!testRelLabel": "memberOf $ c:@U@Vector@FI@Data $ c:@U@Vector"
+// VEC-DAG: "!testRelLabel": "memberOf $ c:@U@Vector@Sa@FI@X $ c:@U@Vector"
+// VEC-DAG: "!testRelLabel": "memberOf $ c:@U@Vector@Sa@FI@Y $ c:@U@Vector"
+
 // expected-no-diagnostics