Keep types in signatures of function types properly instantiated as the function

runtime/lib/mirrors.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "lib/mirrors.h"
 
 #include "lib/invocation_mirror.h"
 #include "vm/bootstrap_natives.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
@@ skipping 948 matching lines @@
 
 
 DEFINE_NATIVE_ENTRY(FunctionTypeMirror_parameters, 2) {
   GET_NON_NULL_NATIVE_ARGUMENT(Instance, owner, arguments->NativeArgAt(0));
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(1));
   const Function& func = Function::Handle(ref.GetFunctionReferent());
   return CreateParameterMirrorList(func, owner);
 }
 
 
-DEFINE_NATIVE_ENTRY(FunctionTypeMirror_return_type, 2) {
+DEFINE_NATIVE_ENTRY(FunctionTypeMirror_return_type, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(0));
-  GET_NON_NULL_NATIVE_ARGUMENT(AbstractType, instantiator,
-                               arguments->NativeArgAt(1));
   const Function& func = Function::Handle(ref.GetFunctionReferent());
   ASSERT(!func.IsNull());
   AbstractType& type = AbstractType::Handle(func.result_type());
-  return InstantiateType(type, instantiator);
+  // Signatures of function types are instantiated, but not canonical.
+  return type.Canonicalize();
 }
 
 
 DEFINE_NATIVE_ENTRY(ClassMirror_libraryUri, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(0));
   const Class& klass = Class::Handle(ref.GetClassReferent());
   const Library& library = Library::Handle(klass.library());
   ASSERT(!library.IsNull());
   return library.url();
 }
@@ skipping 953 matching lines @@
   return CreateParameterMirrorList(func, owner);
 }
 
 
 DEFINE_NATIVE_ENTRY(MethodMirror_return_type, 2) {
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(0));
   const Function& func = Function::Handle(ref.GetFunctionReferent());
   GET_NATIVE_ARGUMENT(AbstractType, instantiator, arguments->NativeArgAt(1));
   // We handle constructors in Dart code.
   ASSERT(!func.IsGenerativeConstructor());
-  const AbstractType& type = AbstractType::Handle(func.result_type());
+  AbstractType& type = AbstractType::Handle(func.result_type());
+  type ^= type.Canonicalize();  // Instantiated signatures are not canonical.
   return InstantiateType(type, instantiator);
 }
 
 
 DEFINE_NATIVE_ENTRY(MethodMirror_source, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(0));
   const Function& func = Function::Handle(ref.GetFunctionReferent());
   return func.GetSource();
 }
 
@@ skipping 103 matching lines @@
   referent_type ^= InstantiateType(referent_type, type);
   return CreateFunctionTypeMirror(referent_type);
 }
 
 
 DEFINE_NATIVE_ENTRY(ParameterMirror_type, 3) {
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(0));
   GET_NON_NULL_NATIVE_ARGUMENT(Smi, pos, arguments->NativeArgAt(1));
   GET_NATIVE_ARGUMENT(AbstractType, instantiator, arguments->NativeArgAt(2));
   const Function& func = Function::Handle(ref.GetFunctionReferent());
-  const AbstractType& type = AbstractType::Handle(
+  AbstractType& type = AbstractType::Handle(
       func.ParameterTypeAt(func.NumImplicitParameters() + pos.Value()));
+  type ^= type.Canonicalize();  // Instantiated signatures are not canonical.
   return InstantiateType(type, instantiator);
 }
 
 
 DEFINE_NATIVE_ENTRY(VariableMirror_type, 2) {
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(0));
   const Field& field = Field::Handle(ref.GetFieldReferent());
   GET_NATIVE_ARGUMENT(AbstractType, instantiator, arguments->NativeArgAt(1));
   const AbstractType& type = AbstractType::Handle(field.type());
   return InstantiateType(type, instantiator);
 }
 
 DEFINE_NATIVE_ENTRY(TypeMirror_subtypeTest, 2) {
   GET_NON_NULL_NATIVE_ARGUMENT(AbstractType, a, arguments->NativeArgAt(0));
   GET_NON_NULL_NATIVE_ARGUMENT(AbstractType, b, arguments->NativeArgAt(1));
   return Bool::Get(a.IsSubtypeOf(b, NULL, NULL, Heap::kNew)).raw();
 }
 
 #endif  // !PRODUCT && !DART_PRECOMPILED_RUNTIME
 
 }  // namespace dart