From c4c09b66e6b4e16a709502b15990525aeaea960f Mon Sep 17 00:00:00 2001
From: JamesWrigley <james@puiterwijk.org>
Date: Sun, 9 Jun 2024 18:33:29 +0200
Subject: [PATCH] Add support for enum forward declarations

These will otherwise create duplicate bindings.
---
 src/CodeTree.cpp  | 4 ++--
 test/TestEnum/A.h | 9 +++++++++
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/CodeTree.cpp b/src/CodeTree.cpp
index fa36d81..3ef38d9 100644
--- a/src/CodeTree.cpp
+++ b/src/CodeTree.cpp
@@ -2121,7 +2121,7 @@ bool CodeTree::add_type_specialization(TypeRcd* pTypeRcd, const CXType& type){
 bool CodeTree::isAForwardDeclaration(CXCursor cursor) const{
   const auto& kind = clang_getCursorKind(cursor);
 
-  auto rc =  (kind == CXCursor_ClassDecl || kind == CXCursor_StructDecl)
+  auto rc =  (kind == CXCursor_ClassDecl || kind == CXCursor_StructDecl || kind == CXCursor_EnumDecl)
     && !clang_equalCursors(clang_getCursorDefinition(cursor), cursor);
 
   const auto& special = clang_getSpecializedCursorTemplate(cursor);
@@ -2234,7 +2234,7 @@ CXChildVisitResult CodeTree::visit(CXCursor cursor, CXCursor parent,
     tree.visit_class(cursor);
   } else if(kind == CXCursor_FunctionDecl){
     tree.visit_global_function(cursor);
-  } else if(kind == CXCursor_EnumDecl){
+  } else if(kind == CXCursor_EnumDecl && !tree.isAForwardDeclaration(cursor)){
     tree.visit_enum(cursor);
   } else if(kind == CXCursor_TypedefDecl){
     //  tree.visit_typedef(cursor);
diff --git a/test/TestEnum/A.h b/test/TestEnum/A.h
index d250191..83d1de1 100644
--- a/test/TestEnum/A.h
+++ b/test/TestEnum/A.h
@@ -12,3 +12,12 @@ enum E {
   E1 = 5,
   E2 = 6
 };
+
+// Only the definition should create a binding, otherwise a duplicate will be
+// created for the forward declaration which will cause an error during
+// precompilation.
+enum ForwardDecl : int;
+enum ForwardDecl : int {
+    X = 1,
+    Y = 2
+};