mfbt/tests/TestTypeTraits.cpp
author Gregory Szorc <gps@mozilla.com>
Wed, 28 Jan 2015 13:37:00 -0800
branchGECKO1703_2013021512_RELBRANCH
changeset 110559 3ba2371322adf61607b0d2271d05b401237026b8
parent 102311 fe817bf85f36386d626ed35383ffb9dae2f4ddc5
permissions -rw-r--r--
Close old release branch GECKO1703_2013021512_RELBRANCH

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/Assertions.h"
#include "mozilla/TypeTraits.h"

using mozilla::IsConvertible;

class A { };
class B : public A { };
class C : private A { };
class D { };

static void
TestIsConvertible()
{
  // Pointer type convertibility
  MOZ_ASSERT((IsConvertible<A*, A*>::value),
             "A* should convert to A*");
  MOZ_ASSERT((IsConvertible<B*, A*>::value),
             "B* should convert to A*");
  MOZ_ASSERT((!IsConvertible<A*, B*>::value),
             "A* shouldn't convert to B*");
  MOZ_ASSERT((!IsConvertible<A*, C*>::value),
             "A* shouldn't convert to C*");
  MOZ_ASSERT((!IsConvertible<A*, D*>::value),
             "A* shouldn't convert to unrelated D*");
  MOZ_ASSERT((!IsConvertible<D*, A*>::value),
             "D* shouldn't convert to unrelated A*");

  // Instance type convertibility
  MOZ_ASSERT((IsConvertible<A, A>::value),
             "A is A");
  MOZ_ASSERT((IsConvertible<B, A>::value),
             "B converts to A");
  MOZ_ASSERT((!IsConvertible<D, A>::value),
             "D and A are unrelated");
  MOZ_ASSERT((!IsConvertible<A, D>::value),
             "A and D are unrelated");

  // These cases seem to require C++11 support to properly implement them, so
  // for now just disable them.
  //MOZ_ASSERT((!IsConvertible<C*, A*>::value),
  //           "C* shouldn't convert to A* (private inheritance)");
  //MOZ_ASSERT((!IsConvertible<C, A>::value),
  //           "C doesn't convert to A (private inheritance)");
}

int
main()
{
  TestIsConvertible();
}