Make Null a public class of dart:core.

runtime/vm/object.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 "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 399 matching lines @@
     cls.set_is_type_finalized();
     cls.raw_ptr()->type_arguments_field_offset_in_words_ =
         Class::kNoTypeArguments;
     cls.raw_ptr()->num_native_fields_ = 0;
     cls.InitEmptyFields();
     isolate->RegisterClass(cls);
   }
 
   // Allocate and initialize the null class.
   cls = Class::New<Instance>(kNullCid);
-  cls.set_is_prefinalized();
   isolate->object_store()->set_null_class(cls);

[regis, 2013/08/15 17:27:26]

Shouldn't this be done in Object::InitFromSnapshot, exactly like for
object_class?

[rmacnak, 2013/08/15 17:56:04]

object_class is also created in both Init(Isolate*) and InitFromSnapshot.

 
   // Allocate and initialize the free list element class.
   cls = Class::New<FreeListElement::FakeInstance>(kFreeListElement);
   cls.set_is_finalized();
   cls.set_is_type_finalized();
 
   // Allocate and initialize the sentinel values of Null class.
   {
     *sentinel_ ^=
         Object::Allocate(kNullCid, Instance::InstanceSize(), Heap::kOld);
@@ skipping 415 matching lines @@
 
   // Now that the symbol table is initialized and that the core dictionary as
   // well as the core implementation dictionary have been setup, preallocate
   // remaining classes and register them by name in the dictionaries.
   String& name = String::Handle();
   cls = Class::New<Bool>();
   object_store->set_bool_class(cls);
   RegisterClass(cls, Symbols::Bool(), core_lib);
   pending_classes.Add(cls, Heap::kOld);
 
-  // TODO(12364): The class 'Null' is not registered in the class dictionary
-  // because it is not exported by dart:core.
   cls = Class::New<Instance>(kNullCid);
+  cls.set_is_prefinalized();
   object_store->set_null_class(cls);
-  cls.set_is_prefinalized();
   RegisterClass(cls, Symbols::Null(), core_lib);
   pending_classes.Add(cls, Heap::kOld);

[regis, 2013/08/15 17:27:26]

Shouldn't this paragraph be moved to after the comment "Allocate and initialize
the pre-allocated classes in the core library." below, since Null is now found
in the core lib? Not required, though.

[rmacnak, 2013/08/15 17:56:04]

Moved null and bool down.

 
   cls = object_store->array_class();  // Was allocated above.
   RegisterPrivateClass(cls, Symbols::ObjectArray(), core_lib);
   pending_classes.Add(cls, Heap::kOld);
   // We cannot use NewNonParameterizedType(cls), because Array is parameterized.
   type ^= Type::New(Object::Handle(cls.raw()),
                     TypeArguments::Handle(),
                     Scanner::kDummyTokenIndex);
   type.SetIsFinalized();
   type ^= type.Canonicalize();
@@ skipping 9587 matching lines @@
   if (HasResolvedTypeClass()) {
     return Class::Handle(type_class()).Name();
   } else {
     return UnresolvedClass::Handle(unresolved_class()).Name();
   }
 }
 
 
 bool AbstractType::IsNullType() const {
   return HasResolvedTypeClass() &&
-      (type_class() == Type::Handle(Type::NullType()).type_class());
+      (type_class() == Isolate::Current()->object_store()->null_class());
 }
 
 
 bool AbstractType::IsBoolType() const {
   return HasResolvedTypeClass() &&
-      (type_class() == Type::Handle(Type::BoolType()).type_class());
+      (type_class() == Isolate::Current()->object_store()->bool_class());
 }
 
 
 bool AbstractType::IsIntType() const {
   return HasResolvedTypeClass() &&
       (type_class() == Type::Handle(Type::IntType()).type_class());
 }
 
 
 bool AbstractType::IsDoubleType() const {
@@ skipping 4120 matching lines @@
 }
 
 
 void MirrorReference::PrintToJSONStream(JSONStream* stream, bool ref) const {
   stream->OpenObject();
   stream->CloseObject();
 }
 
 
 }  // namespace dart