libcxx/test/std/containers/container.adaptors/flat.set/flat.set.cons/copy_assign.pass.cpp

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20

// <flat_set>

// flat_set& operator=(const flat_set& m);

#include <algorithm>
#include <deque>
#include <flat_set>
#include <functional>
#include <vector>

#include "operator_hijacker.h"
#include "test_macros.h"
#include "../../../test_compare.h"
#include "test_allocator.h"

template <template <class...> class KeyContainer>
constexpr void test() {
  {
    // test_allocator is not propagated
    using C = test_less<int>;
    KeyContainer<int, test_allocator<int>> ks({1, 3, 5}, test_allocator<int>(6));
    using M = std::flat_set<int, C, decltype(ks)>;
    auto mo = M(ks, C(5));
    auto m  = M({{3, 4, 5}}, C(3), test_allocator<int>(2));
    m       = mo;

    assert(m.key_comp() == C(5));
    assert(std::ranges::equal(m, ks));
    auto keys = std::move(m).extract();
    assert(keys.get_allocator() == test_allocator<int>(2));

    // mo is unchanged
    assert(mo.key_comp() == C(5));
    assert(std::ranges::equal(mo, ks));
    auto keys2 = std::move(mo).extract();
    assert(keys2.get_allocator() == test_allocator<int>(6));
  }
  {
    // other_allocator is propagated
    using C  = test_less<int>;
    using Ks = KeyContainer<int, other_allocator<int>>;
    auto ks  = Ks({1, 3, 5}, other_allocator<int>(6));
    using M  = std::flat_set<int, C, Ks>;
    auto mo  = M(Ks(ks, other_allocator<int>(6)), C(5));
    auto m   = M({3, 4, 5}, C(3), other_allocator<int>(2));
    m        = mo;

    assert(m.key_comp() == C(5));
    assert(std::ranges::equal(m, ks));
    auto keys = std::move(m).extract();
    assert(keys.get_allocator() == other_allocator<int>(6));

    // mo is unchanged
    assert(mo.key_comp() == C(5));
    assert(std::ranges::equal(mo, ks));
    auto keys2 = std::move(mo).extract();
    assert(keys2.get_allocator() == other_allocator<int>(6));
  }
  if (!TEST_IS_CONSTANT_EVALUATED) {
    // comparator is copied and invariant is preserved
    using M = std::flat_set<int, std::function<bool(int, int)>, KeyContainer<int>>;
    M mo    = M({1, 2}, std::less<int>());
    M m     = M({1, 2}, std::greater<int>());
    assert(m.key_comp()(2, 1) == true);
    assert(m != mo);
    m = mo;
    assert(m.key_comp()(2, 1) == false);
    assert(m == mo);
  }
  {
    // self-assignment
    using M = std::flat_set<int, std::less<int>, KeyContainer<int>>;
    M m     = {{1, 2}};
    m       = static_cast<const M&>(m);
    assert((m == M{{1, 2}}));
  }
  {
    // Validate whether the container can be copy-assigned (move-assigned, swapped)
    // with an ADL-hijacking operator&
    std::flat_set<operator_hijacker> so;
    std::flat_set<operator_hijacker> s;
    s = so;
    s = std::move(so);
    swap(s, so);
  }
}

constexpr bool test() {
  test<std::vector>();
#ifndef __cpp_lib_constexpr_deque
  if (!TEST_IS_CONSTANT_EVALUATED)
#endif
    test<std::deque>();

  return true;
}

int main(int, char**) {
  test();
#if TEST_STD_VER >= 26
  static_assert(test());
#endif

  return 0;
}