Mark class as typedef class before parsing its function type when using the new

runtime/vm/parser.cc

Index: runtime/vm/parser.cc
diff --git a/runtime/vm/parser.cc b/runtime/vm/parser.cc
index 32c3ff7bb5d4f2cf6d787db2a26e9aa2310f4611..0ab4794097cc27b1c13f368ede8b8f774cffaa8e 100644
--- a/runtime/vm/parser.cc
+++ b/runtime/vm/parser.cc
@@ -5471,24 +5471,27 @@ void Parser::ParseTypedef(const GrowableObjectArray& pending_classes,
   function_type_alias.set_is_synthesized_class();
   function_type_alias.set_is_abstract();
   function_type_alias.set_is_prefinalized();
+  // Make sure the function type alias can be recognized as a typedef class by
+  // setting its signature function. When use_function_type_syntax is true, this
+  // temporary signature function is replaced while parsing the function type.
+  Function& signature_function = Function::Handle(
+      Z, Function::NewSignatureFunction(function_type_alias,
+                                        Function::Handle(Z), alias_name_pos));
+  function_type_alias.set_signature_function(signature_function);
   library_.AddClass(function_type_alias);
+  ASSERT(function_type_alias.IsTypedefClass());
   ASSERT(current_class().IsTopLevel());
   set_current_class(function_type_alias);
   // Parse the type parameters of the typedef class.
   ParseTypeParameters(true);  // Parameterizing current class.
-  Function& signature_function = Function::Handle(Z);
   ASSERT(innermost_function().IsNull());
   if (use_function_type_syntax) {
     ExpectToken(Token::kASSIGN);
     ASSERT(result_type.IsNull());  // Not parsed yet.
-    // Do not resolve types before the function type alias can be recognized as
-    // a typedef class, so that correct promotion of function types can occur.
     const Type& function_type = Type::Handle(
         Z, ParseFunctionType(result_type, ClassFinalizer::kDoNotResolve));
     signature_function = function_type.signature();
   } else {
-    signature_function = Function::NewSignatureFunction(
-        function_type_alias, Function::Handle(Z), alias_name_pos);
     innermost_function_ = signature_function.raw();
     ParamList params;
     // Parse the formal parameters of the function type.
@@ -5511,9 +5514,7 @@ void Parser::ParseTypedef(const GrowableObjectArray& pending_classes,
   }
   ExpectSemicolon();
   ASSERT(innermost_function().IsNull());
-
-  // Set the signature function in the function type alias class.
-  function_type_alias.set_signature_function(signature_function);
+  ASSERT(function_type_alias.signature_function() == signature_function.raw());
 
   // At this point, all function type parameters have been parsed and the class
   // function_type_alias is recognized as a typedef, so we can resolve all type
@@ -13402,6 +13403,12 @@ RawType* Parser::ParseFunctionType(
                              &params);
     AddFormalParamsToFunction(&params, signature_function);
     innermost_function_ = innermost_function_.parent_function();
+    if (innermost_function().IsNull() && current_class().IsTypedefClass() &&
+        !IsFunctionTypeSymbol()) {
+      // The last parsed signature function is the typedef signature function.
+      // Set it in the typedef class before building the signature type.
+      current_class().set_signature_function(signature_function);
+    }
     type = signature_function.SignatureType();
   } while (IsFunctionTypeSymbol());
   // At this point, all type parameters have been parsed, resolve the type.