Generate dynamic type errors according to spec.

runtime/vm/dart_api_impl.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 "include/dart_api.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
 #include "vm/dart.h"
@@ skipping 928 matching lines @@
   }
   const Object& obj = Object::Handle(Api::UnwrapHandle(object));
   Instance& instance = Instance::Handle();
   instance ^= obj.raw();
   // Finalize all classes.
   const char* msg = CheckIsolateState(isolate);
   if (msg != NULL) {
     return Api::NewError(msg);
   }
   const Type& type = Type::Handle(Type::NewNonParameterizedType(cls));
-  *value = instance.IsInstanceOf(type, TypeArguments::Handle());
+  Error& malformed_type_error = Error::Handle();
+  *value = instance.IsInstanceOf(
+      type, TypeArguments::Handle(), &malformed_type_error);
+  ASSERT(malformed_type_error.IsNull());  // Type was created here from a class.
   return Api::Success();
 }
 
 
 // --- Numbers ----
 
 
 // TODO(iposva): The argument should be an instance.
 DART_EXPORT bool Dart_IsNumber(Dart_Handle object) {
   DARTSCOPE(Isolate::Current());
@@ skipping 453 matching lines @@
 
 
 // --- Lists ---
 
 
 static RawInstance* GetListInstance(Isolate* isolate, const Object& obj) {
   if (obj.IsInstance()) {
     Instance& instance = Instance::Handle();
     instance ^= obj.raw();
     const Type& type = Type::Handle(isolate->object_store()->list_interface());
-    if (instance.IsInstanceOf(type, TypeArguments::Handle())) {
+    Error& malformed_type_error = Error::Handle();
+    if (instance.IsInstanceOf(type,
+                              TypeArguments::Handle(),
+                              &malformed_type_error)) {
+      ASSERT(malformed_type_error.IsNull());  // Type is a raw List.
       return instance.raw();
     }
   }
   return Instance::null();
 }
 
 
 DART_EXPORT bool Dart_IsList(Dart_Handle object) {
   Isolate* isolate = Isolate::Current();
   DARTSCOPE(isolate);
@@ skipping 1309 matching lines @@
       *buffer = NULL;
     }
     delete debug_region;
   } else {
     *buffer = NULL;
     *buffer_size = 0;
   }
 }
 
 }  // namespace dart