Make Callback.Equals() only work when comparing against the same type.

base/bind_unittest.nc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/callback.h"
 #include "base/bind.h"
 
 namespace base {
 
 // Do not put everything inside an anonymous namespace.  If you do, many of the
@@ skipping 62 matching lines @@
 //
 // Only const methods should be allowed to work with const objects.
 void WontCompile() {
   HasRef has_ref;
   const HasRef* const_has_ref_ptr_ = &has_ref;
   Callback<void(void)> method_to_const_cb =
       Bind(&HasRef::VoidMethod0, const_has_ref_ptr_);
   method_to_const_cb.Run();
 }
 
-#elif defined(NCTEST_CONSTRUCTION_FROM_SUBTYPE)  // [r"conversion from 'base::Callback<int\(\)>' to non-scalar type 'base::Callback<void\(\)>'"]
-
-// Construction of Callback<A> from Callback<B> if A is supertype of B.
-//
-// While this is technically safe, most people aren't used to it when coding
-// C++ so if this is happening, it is almost certainly an error.
-void WontCompile() {
-  Callback<int(void)> cb_a = Bind(&PolymorphicIdentity<int>, 1);
-  Callback<void(void)> cb_b = cb_a;
-}
-
-#elif defined(NCTEST_ASSIGNMENT_FROM_SUBTYPE)  // [r"no match for 'operator=' in 'cb_a = cb_b'"]
-
-// Assignment of Callback<A> from Callback<B> if A is supertype of B.
-// See explanation for NCTEST_CONSTRUCTION_FROM_SUBTYPE
-void WontCompile() {
-  Callback<int(void)> cb_a = Bind(&PolymorphicIdentity<int>, 1);
-  Callback<void(void)> cb_b;
-  cb_a = cb_b;
-}
-
 #elif defined(NCTEST_METHOD_BIND_NEEDS_REFCOUNTED_OBJECT)  // [r"has no member named 'AddRef'"]
 
 // Method bound to non-refcounted object.
 //
 // We require refcounts unless you have Unretained().
 void WontCompile() {
   NoRef no_ref;
   Callback<void(void)> no_ref_cb =
       Bind(&NoRef::VoidMethod0, &no_ref);
   no_ref_cb.Run();
@@ skipping 100 matching lines @@
 #elif defined(NCTEST_DISALLOW_ASSIGN_DIFFERINT_TYPES)  // [r"creating array with negative size"]
 
 // Bind result cannot be assigned to Callbacks with a mismatching type.
 void WontCompile() {
   Closure callback_mismatches_bind_type = Bind(&VoidPolymorphic1<int>);
 }
 
 #endif
 
 }  // namespace base