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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03
// <utility>
// template <class T1, class T2> struct pair
// pair& operator=(pair&& p);
#include <utility>
#include <memory>
#include <cassert>
struct NonAssignable {
NonAssignable& operator=(NonAssignable const&) = delete;
NonAssignable& operator=(NonAssignable&&) = delete;
};
struct CopyAssignable {
CopyAssignable() = default;
CopyAssignable& operator=(CopyAssignable const&) = default;
CopyAssignable& operator=(CopyAssignable&&) = delete;
};
struct MoveAssignable {
MoveAssignable() = default;
MoveAssignable& operator=(MoveAssignable const&) = delete;
MoveAssignable& operator=(MoveAssignable&&) = default;
};
struct CountAssign {
static int copied;
static int moved;
static void reset() { copied = moved = 0; }
CountAssign() = default;
CountAssign& operator=(CountAssign const&) { ++copied; return *this; }
CountAssign& operator=(CountAssign&&) { ++moved; return *this; }
};
int CountAssign::copied = 0;
int CountAssign::moved = 0;
int main()
{
{
typedef std::pair<std::unique_ptr<int>, int> P;
P p1(std::unique_ptr<int>(new int(3)), 4);
P p2;
p2 = std::move(p1);
assert(*p2.first == 3);
assert(p2.second == 4);
}
{
using P = std::pair<int&, int&&>;
int x = 42;
int y = 101;
int x2 = -1;
int y2 = 300;
P p1(x, std::move(y));
P p2(x2, std::move(y2));
p1 = std::move(p2);
assert(p1.first == x2);
assert(p1.second == y2);
}
{
using P = std::pair<int, NonAssignable>;
static_assert(!std::is_move_assignable<P>::value, "");
}
{
// The move decays to the copy constructor
CountAssign::reset();
using P = std::pair<CountAssign, CopyAssignable>;
static_assert(std::is_move_assignable<P>::value, "");
P p;
P p2;
p = std::move(p2);
assert(CountAssign::moved == 0);
assert(CountAssign::copied == 1);
}
{
CountAssign::reset();
using P = std::pair<CountAssign, MoveAssignable>;
static_assert(std::is_move_assignable<P>::value, "");
P p;
P p2;
p = std::move(p2);
assert(CountAssign::moved == 1);
assert(CountAssign::copied == 0);
}
}
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