xref: /llvm-project-15.0.7/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/deduction.pass.cpp (revision 6b9e0af8)

//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//

// <memory>
// UNSUPPORTED: c++03, c++11, c++14

// template<class T> class shared_ptr

// shared_ptr(weak_ptr<T>) -> shared_ptr<T>
// shared_ptr(unique_ptr<T>) -> shared_ptr<T>

#include <memory>
#include <cassert>

#include "test_macros.h"

struct A {};

struct D {
  void operator()(A const* ptr) const
  {
    delete ptr;
  }
};

int main(int, char**)
{
  {
    std::shared_ptr<A> s0(new A);
    std::weak_ptr<A> w = s0;
    auto s = std::shared_ptr(w);
    ASSERT_SAME_TYPE(decltype(s), std::shared_ptr<A>);
    assert(s0.use_count() == 2);
    assert(s.use_count() == 2);
    assert(s0.get() == s.get());
  }
  {
    std::shared_ptr<A const> s0(new A);
    std::weak_ptr<A const> w = s0;
    auto s = std::shared_ptr(w);
    ASSERT_SAME_TYPE(decltype(s), std::shared_ptr<A const>);
    assert(s0.use_count() == 2);
    assert(s.use_count() == 2);
    assert(s0.get() == s.get());
  }

  {
    std::unique_ptr<A> u(new A);
    A* uPointee = u.get();
    std::shared_ptr s = std::move(u);
    ASSERT_SAME_TYPE(decltype(s), std::shared_ptr<A>);
    assert(u == nullptr);
    assert(s.get() == uPointee);
  }
  {
    std::unique_ptr<A const> u(new A);
    A const* uPointee = u.get();
    std::shared_ptr s = std::move(u);
    ASSERT_SAME_TYPE(decltype(s), std::shared_ptr<A const>);
    assert(u == nullptr);
    assert(s.get() == uPointee);
  }

  {
    std::unique_ptr<A, D> u(new A, D{});
    A* uPointee = u.get();
    std::shared_ptr s(std::move(u));
    ASSERT_SAME_TYPE(decltype(s), std::shared_ptr<A>);
    assert(u == nullptr);
    assert(s.get() == uPointee);
  }
  {
    std::unique_ptr<A const, D> u(new A, D{});
    A const* uPointee = u.get();
    std::shared_ptr s(std::move(u));
    ASSERT_SAME_TYPE(decltype(s), std::shared_ptr<A const>);
    assert(u == nullptr);
    assert(s.get() == uPointee);
  }

  return 0;
}