LibCpp: Introduce DummyASTNode

This allows us to use pase_* methods inside match_* methods,
without adding any actual AST nodes to the m_nodes list.

1 files changed, 13 insertions, 3 deletions

diff --git a/Userland/Libraries/LibCpp/Parser.h b/Userland/Libraries/LibCpp/Parser.h
index 0fff5f685d..94961e6968 100644
--- a/Userland/Libraries/LibCpp/Parser.h
+++ b/Userland/Libraries/LibCpp/Parser.h
@@ -155,6 +155,7 @@ private:
     struct State {
         size_t token_index { 0 };
         Vector<String> errors;
+        NonnullRefPtrVector<ASTNode> nodes;
     };
 
     void error(StringView message = {});
@@ -164,7 +165,9 @@ private:
     create_ast_node(ASTNode& parent, const Position& start, Optional<Position> end, Args&&... args)
     {
         auto node = adopt(*new T(&parent, start, end, m_filename, forward<Args>(args)...));
-        m_nodes.append(node);
+        if(!parent.is_dummy_node()) {
+            m_state.nodes.append(node);
+        }
         return node;
     }
 
@@ -172,11 +175,19 @@ private:
     create_root_ast_node(const Position& start, Position end)
     {
         auto node = adopt(*new TranslationUnit(nullptr, start, end, m_filename));
-        m_nodes.append(node);
+        m_state.nodes.append(node);
         m_root_node = node;
         return node;
     }
 
+
+    DummyAstNode& get_dummy_node()
+    {
+        static NonnullRefPtr<DummyAstNode> dummy  = adopt(*new DummyAstNode(nullptr, {}, {}, {}));
+        return dummy;
+    }
+
+
     bool match_attribute_specification();
     void consume_attribute_specification();
     bool match_ellipsis();
@@ -191,7 +202,6 @@ private:
     State m_state;
     Vector<State> m_saved_states;
     RefPtr<TranslationUnit> m_root_node;
-    NonnullRefPtrVector<ASTNode> m_nodes;
 
     Vector<TokenAndPreprocessorDefinition> m_replaced_preprocessor_tokens;
 };