shaka-packager/base/callback_unittest.nc

51 lines
1.5 KiB
Plaintext

// 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"
namespace base {
class Parent {
};
class Child : Parent {
};
#if defined(NCTEST_EQUALS_REQUIRES_SAMETYPE) // [r"no matching function for call to 'base::Callback<void\(\)>::Equals\(base::Callback<int\(\)>&\)'"]
// Attempting to call comparison function on two callbacks of different type.
//
// This should be a compile time failure because each callback type should be
// considered distinct.
void WontCompile() {
Closure c1;
Callback<int(void)> c2;
c1.Equals(c2);
}
#elif defined(NCTEST_CONSTRUCTION_FROM_SUBTYPE) // [r"conversion from 'base::Callback<base::Parent\(\)>' to non-scalar type 'base::Callback<base::Child\(\)>'"]
// 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<Parent(void)> cb_a;
Callback<Child(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<Parent(void)> cb_a;
Callback<Child(void)> cb_b;
cb_a = cb_b;
}
#endif
} // namespace base