1// Copyright (c) 2011 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#include "base/callback.h" 6 7namespace base { 8 9class Parent { 10}; 11 12class Child : Parent { 13}; 14 15#if defined(NCTEST_EQUALS_REQUIRES_SAMETYPE) // [r"no matching function for call to 'base::Callback<void\(\)>::Equals\(base::Callback<int\(\)>&\)'"] 16 17// Attempting to call comparison function on two callbacks of different type. 18// 19// This should be a compile time failure because each callback type should be 20// considered distinct. 21void WontCompile() { 22 Closure c1; 23 Callback<int(void)> c2; 24 c1.Equals(c2); 25} 26 27#elif defined(NCTEST_CONSTRUCTION_FROM_SUBTYPE) // [r"conversion from 'base::Callback<base::Parent\(\)>' to non-scalar type 'base::Callback<base::Child\(\)>'"] 28 29// Construction of Callback<A> from Callback<B> if A is supertype of B. 30// 31// While this is technically safe, most people aren't used to it when coding 32// C++ so if this is happening, it is almost certainly an error. 33void WontCompile() { 34 Callback<Parent(void)> cb_a; 35 Callback<Child(void)> cb_b = cb_a; 36} 37 38#elif defined(NCTEST_ASSIGNMENT_FROM_SUBTYPE) // [r"no match for 'operator=' in 'cb_a = cb_b'"] 39 40// Assignment of Callback<A> from Callback<B> if A is supertype of B. 41// See explanation for NCTEST_CONSTRUCTION_FROM_SUBTYPE 42void WontCompile() { 43 Callback<Parent(void)> cb_a; 44 Callback<Child(void)> cb_b; 45 cb_a = cb_b; 46} 47 48#endif 49 50} // namespace base 51