[clang] [clang][ExtractAPI] Add ability to create multiple symbol graphs (PR #86676)

[via cfe-commits]

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@@ -242,79 +260,168 @@ struct APIRecord {
   /// Objective-C class/instance methods).
   DeclarationFragments SubHeading;
 
-  /// Information about the parent record of this record.
-  HierarchyInformation ParentInformation;
-
   /// Whether the symbol was defined in a system header.
   bool IsFromSystemHeader;
 
+  AccessControl Access;
+
 private:
   const RecordKind Kind;
+  friend class RecordContext;
+  // Used to store the next child record in RecordContext. This works because
+  // APIRecords semantically only have one parent.
+  mutable APIRecord *NextInContex = nullptr;
 
 public:
+  APIRecord *getNextInContex() const { return NextInContex; }
+
   RecordKind getKind() const { return Kind; }
 
+  static APIRecord *castFromRecordContext(const RecordContext *Ctx);
+  static RecordContext *castToRecordContext(const APIRecord *Record);
+
   APIRecord() = delete;
 
   APIRecord(RecordKind Kind, StringRef USR, StringRef Name,
-            PresumedLoc Location, AvailabilityInfo Availability,
-            LinkageInfo Linkage, const DocComment &Comment,
-            DeclarationFragments Declaration, DeclarationFragments SubHeading,
-            bool IsFromSystemHeader)
-      : USR(USR), Name(Name), Location(Location),
+            SymbolReference Parent, PresumedLoc Location,
+            AvailabilityInfo Availability, LinkageInfo Linkage,
+            const DocComment &Comment, DeclarationFragments Declaration,
+            DeclarationFragments SubHeading, bool IsFromSystemHeader,
+            AccessControl Access = AccessControl())
+      : USR(USR), Name(Name), Parent(std::move(Parent)), Location(Location),
         Availability(std::move(Availability)), Linkage(Linkage),
         Comment(Comment), Declaration(Declaration), SubHeading(SubHeading),
-        IsFromSystemHeader(IsFromSystemHeader), Kind(Kind) {}
+        IsFromSystemHeader(IsFromSystemHeader), Access(std::move(Access)),
+        Kind(Kind) {}
 
   APIRecord(RecordKind Kind, StringRef USR, StringRef Name)
       : USR(USR), Name(Name), Kind(Kind) {}
 
   // Pure virtual destructor to make APIRecord abstract
   virtual ~APIRecord() = 0;
+  static bool classof(const APIRecord *Record) { return true; }
+  static bool classofKind(RecordKind K) { return true; }
+  static bool classof(const RecordContext *Ctx) { return true; }
+};
+
+/// Base class used for specific record types that have children records this is
+/// analogous to the DeclContext for the AST
+class RecordContext {
+public:
+  static bool classof(const APIRecord *Record) {
+    return classofKind(Record->getKind());
+  }
+  static bool classofKind(APIRecord::RecordKind K) {
+    return K >= APIRecord::RK_Namespace &&
+           K <= APIRecord::RK_ClassTemplatePartialSpecialization;
+  }
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QuietMisdreavus wrote:

Would it be possible to add tombstones for `FirstRecordContext`/`LastRecordContext` to make this easier to maintain?

https://github.com/llvm/llvm-project/pull/86676