Stop prefixing the library name to type names when reporting a type error with

runtime/vm/code_generator.cc

 // Copyright (c) 2013, 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 "vm/code_generator.h"
 
 #include "vm/assembler.h"
 #include "vm/ast.h"
 #include "vm/code_patcher.h"
 #include "vm/compiler.h"
@@ skipping 476 matching lines @@
 // Check that the type of the given instance is a subtype of the given type and
 // can therefore be assigned.
 // Arg0: instance being assigned.
 // Arg1: type being assigned to.
 // Arg2: type arguments of the instantiator of the type being assigned to.
 // Arg3: name of variable being assigned to.
 // Arg4: SubtypeTestCache.
 // Return value: instance if a subtype, otherwise throw a TypeError.
 DEFINE_RUNTIME_ENTRY(TypeCheck, 5) {
   const Instance& src_instance = Instance::CheckedHandle(arguments.ArgAt(0));
-  const AbstractType& dst_type =
-      AbstractType::CheckedHandle(arguments.ArgAt(1));
+  AbstractType& dst_type = AbstractType::CheckedHandle(arguments.ArgAt(1));
   const TypeArguments& instantiator_type_arguments =
       TypeArguments::CheckedHandle(arguments.ArgAt(2));
   const String& dst_name = String::CheckedHandle(arguments.ArgAt(3));
   const SubtypeTestCache& cache =
       SubtypeTestCache::CheckedHandle(arguments.ArgAt(4));
   ASSERT(!dst_type.IsDynamicType());  // No need to check assignment.
   ASSERT(!dst_type.IsMalformed());  // Already checked in code generator.
   ASSERT(!dst_type.IsMalbounded());  // Already checked in code generator.
   ASSERT(!src_instance.IsNull());  // Already checked in inlined code.
 
   Error& bound_error = Error::Handle();
   const bool is_instance_of = src_instance.IsInstanceOf(
       dst_type, instantiator_type_arguments, &bound_error);
 
   if (FLAG_trace_type_checks) {
     PrintTypeCheck("TypeCheck",
                    src_instance, dst_type, instantiator_type_arguments,
                    Bool::Get(is_instance_of));
   }
   if (!is_instance_of) {
     // Throw a dynamic type error.
     const TokenPosition location = GetCallerLocation();
     const AbstractType& src_type = AbstractType::Handle(src_instance.GetType());
     String& src_type_name = String::Handle(src_type.UserVisibleName());
-    String& dst_type_name = String::Handle();
-    Library& dst_type_lib = Library::Handle();
     if (!dst_type.IsInstantiated()) {
       // Instantiate dst_type before reporting the error.
-      const AbstractType& instantiated_dst_type = AbstractType::Handle(
-          dst_type.InstantiateFrom(instantiator_type_arguments, NULL,
-                                   NULL, NULL, Heap::kNew));
-      // Note that instantiated_dst_type may be malbounded.
-      dst_type_name = instantiated_dst_type.UserVisibleName();
-      dst_type_lib =
-          Class::Handle(instantiated_dst_type.type_class()).library();
-    } else {
-      dst_type_name = dst_type.UserVisibleName();
-      dst_type_lib = Class::Handle(dst_type.type_class()).library();
+      dst_type = dst_type.InstantiateFrom(instantiator_type_arguments, NULL,
+                                          NULL, NULL, Heap::kNew);
+      // Note that instantiated dst_type may be malbounded.
     }
+    String& dst_type_name = String::Handle(dst_type.UserVisibleName());

[srdjan, 2016/02/26 17:54:16]

const String

     String& bound_error_message =  String::Handle();
     if (!bound_error.IsNull()) {
       ASSERT(isolate->type_checks());
       bound_error_message = String::New(bound_error.ToErrorCString());
     }

[srdjan, 2016/02/26 17:54:15]

I would still report something special when both src_type and dts_type have the
same name

-    if (src_type_name.Equals(dst_type_name)) {
-      // Qualify the names with their libraries.
-      String& lib_name = String::Handle();
-      lib_name = Library::Handle(
-          Class::Handle(src_type.type_class()).library()).name();
-      if (lib_name.Length() != 0) {
-        lib_name = String::Concat(lib_name, Symbols::Dot());
-        src_type_name = String::Concat(lib_name, src_type_name);
-      }
-      lib_name = dst_type_lib.name();
-      if (lib_name.Length() != 0) {
-        lib_name = String::Concat(lib_name, Symbols::Dot());
-        dst_type_name = String::Concat(lib_name, dst_type_name);
-      }
-    }
     Exceptions::CreateAndThrowTypeError(location, src_type_name, dst_type_name,
                                         dst_name, bound_error_message);
     UNREACHABLE();
   }
   UpdateTypeTestCache(
       src_instance, dst_type, instantiator_type_arguments, Bool::True(), cache);
   arguments.SetReturn(src_instance);
 }
 
 
@@ skipping 1326 matching lines @@
   const intptr_t elm_size = old_data.ElementSizeInBytes();
   const TypedData& new_data =
       TypedData::Handle(TypedData::New(cid, new_size, Heap::kOld));
   TypedData::Copy(new_data, 0, old_data, 0, old_size * elm_size);
   typed_data_cell.SetAt(0, new_data);
   arguments.SetReturn(new_data);
 }
 
 
 }  // namespace dart