libcxx/test/std/containers/container.adaptors/flat.set/flat.set.cons/containers.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>

// explicit flat_set(container_type key_cont, const key_compare& comp = key_compare());
// template<class Allocator>
//   flat_set(const container_type& key_cont, const Allocator& a);
// template<class Alloc>
//   flat_set(const container_type& key_cont, const key_compare& comp, const Alloc& a);

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

#include "min_allocator.h"
#include "MoveOnly.h"
#include "test_allocator.h"
#include "test_iterators.h"
#include "test_macros.h"
#include "../../../test_compare.h"

template <class T>
void conversion_test(T);

template <class T, class... Args>
concept ImplicitlyConstructible = requires(Args&&... args) { conversion_test<T>({std::forward<Args>(args)...}); };

template <template <class...> class KeyContainer>
constexpr void test() {
  {
    // flat_set(container_type)
    using M              = std::flat_set<int, std::less<int>, KeyContainer<int>>;
    KeyContainer<int> ks = {1, 1, 1, 2, 2, 3, 2, 3, 3};
    auto m               = M(ks);
    assert(std::ranges::equal(m, std::vector<int>{1, 2, 3}));

    // explicit
    static_assert(std::is_constructible_v<M, const KeyContainer<int>&>);
    static_assert(!ImplicitlyConstructible<M, const KeyContainer<int>&>);
  }
  {
    // flat_set(container_type)
    // move-only
    MoveOnly expected[] = {3, 2, 1};
    using Ks            = KeyContainer<MoveOnly, min_allocator<MoveOnly>>;
    using M             = std::flat_set<MoveOnly, std::greater<MoveOnly>, Ks>;
    Ks ks;
    ks.push_back(1);
    ks.push_back(3);
    ks.push_back(2);
    auto m = M(std::move(ks));
    assert(ks.empty()); // it was moved-from
    assert(std::ranges::equal(m, expected));
  }
  {
    // flat_set(container_type)
    // container's allocator is used
    using A = test_allocator<int>;
    using M = std::flat_set<int, std::less<int>, KeyContainer<int, A>>;
    auto ks = KeyContainer<int, A>({1, 1, 1, 2, 2, 3, 2, 3, 3}, A(5));
    auto m  = M(std::move(ks));
    assert(ks.empty()); // it was moved-from
    assert((m == M{1, 2, 3}));
    auto keys = std::move(m).extract();
    assert(keys.get_allocator() == A(5));
  }
  {
    // flat_set(container_type , key_compare)
    using C              = test_less<int>;
    using M              = std::flat_set<int, C, KeyContainer<int>>;
    KeyContainer<int> ks = {1, 1, 1, 2, 2, 3, 2, 3, 3};
    auto m               = M(ks, C(4));
    assert(std::ranges::equal(m, std::vector<int>{1, 2, 3}));
    assert(m.key_comp() == C(4));

    // explicit
    static_assert(std::is_constructible_v<M, const KeyContainer<int>&, const C&>);
    static_assert(!ImplicitlyConstructible<M, const KeyContainer<int>&, const C&>);
  }
  {
    // flat_set(container_type , const Allocator&)
    using A = test_allocator<int>;
    using M = std::flat_set<int, std::less<int>, KeyContainer<int, A>>;
    auto ks = KeyContainer<int, A>({1, 1, 1, 2, 2, 3, 2, 3, 3}, A(5));
    auto m  = M(ks, A(4)); // replaces the allocators
    assert(!ks.empty());   // it was an lvalue above
    assert((m == M{1, 2, 3}));
    auto keys = M(m).extract();
    assert(keys.get_allocator() == A(4));

    // explicit(false)
    static_assert(ImplicitlyConstructible<M, const KeyContainer<int, A>&, const A&>);
    M m2 = {ks, A(4)};   // implicit ctor
    assert(!ks.empty()); // it was an lvalue above
    assert(m2 == m);
    auto keys2 = std::move(m).extract();
    assert(keys2.get_allocator() == A(4));
  }
  {
    // flat_set(container_type , key_compare, const Allocator&)
    using C                 = test_less<int>;
    using A                 = test_allocator<int>;
    using M                 = std::flat_set<int, C, KeyContainer<int, A>>;
    KeyContainer<int, A> ks = {1, 1, 1, 2, 2, 3, 2, 3, 3};
    auto m                  = M(ks, C(4), A(5));
    assert(std::ranges::equal(m, std::vector<int, A>{1, 2, 3}));
    assert(m.key_comp() == C(4));
    auto m_copy = m;
    auto keys   = std::move(m_copy).extract();
    assert(keys.get_allocator() == A(5));

    // explicit(false)
    static_assert(ImplicitlyConstructible<M, const KeyContainer<int, A>&, const A&>);
    M m2 = {ks, C(4), A(5)};
    assert(m2 == m);
    assert(m2.key_comp() == C(4));
    keys = std::move(m2).extract();
    assert(keys.get_allocator() == A(5));
  }
}

constexpr bool test() {
  {
    // The constructors in this subclause shall not participate in overload
    // resolution unless uses_allocator_v<container_type, Alloc> is true.

    using C  = test_less<int>;
    using A1 = test_allocator<int>;
    using A2 = other_allocator<int>;
    using V1 = std::vector<int, A1>;
    using V2 = std::vector<int, A2>;
    using M1 = std::flat_set<int, C, V1>;
    using M2 = std::flat_set<int, C, V2>;
    static_assert(std::is_constructible_v<M1, const V1&, const A1&>);
    static_assert(std::is_constructible_v<M2, const V2&, const A2&>);
    static_assert(!std::is_constructible_v<M1, const V1&, const A2&>);
    static_assert(!std::is_constructible_v<M2, const V2&, const A1&>);

    static_assert(std::is_constructible_v<M1, const V1&, const C&, const A1&>);
    static_assert(std::is_constructible_v<M2, const V2&, const C&, const A2&>);
    static_assert(!std::is_constructible_v<M1, const V1&, const C&, const A2&>);
    static_assert(!std::is_constructible_v<M2, const V2&, const C&, const A1&>);
  }

  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;
}