test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.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

// <memory>

// unique_ptr

// Test unique_ptr converting move ctor

#include <memory>
#include <cassert>

#include "test_macros.h"
#include "type_id.h"
#include "unique_ptr_test_helper.h"

template <int ID = 0>
struct GenericDeleter {
  void operator()(void*) const {}
};

template <int ID = 0>
struct GenericConvertingDeleter {
  template <int OID>
  GenericConvertingDeleter(GenericConvertingDeleter<OID>) {}
  void operator()(void*) const {}
};

template <class Templ, class Other>
struct is_specialization;

template <template <int> class Templ, int ID1, class Other>
struct is_specialization<Templ<ID1>, Other> : std::false_type {};

template <template <int> class Templ, int ID1, int ID2>
struct is_specialization<Templ<ID1>, Templ<ID2> > : std::true_type {};

template <class Templ, class Other>
using EnableIfSpecialization = typename std::enable_if<
    is_specialization<Templ, typename std::decay<Other>::type >::value
  >::type;


template <int ID>
struct TrackingDeleter {
  TrackingDeleter() : arg_type(&makeArgumentID<>()) {}

  TrackingDeleter(TrackingDeleter const&)
      : arg_type(&makeArgumentID<TrackingDeleter const&>()) {}

  TrackingDeleter(TrackingDeleter&&)
      : arg_type(&makeArgumentID<TrackingDeleter &&>()) {}

  template <class T, class = EnableIfSpecialization<TrackingDeleter, T> >
  TrackingDeleter(T&&) : arg_type(&makeArgumentID<T&&>()) {}

  TrackingDeleter& operator=(TrackingDeleter const&) {
    arg_type = &makeArgumentID<TrackingDeleter const&>();
    return *this;
  }

  TrackingDeleter& operator=(TrackingDeleter &&) {
    arg_type = &makeArgumentID<TrackingDeleter &&>();
    return *this;
  }

  template <class T, class = EnableIfSpecialization<TrackingDeleter, T> >
  TrackingDeleter& operator=(T&&) {
    arg_type = &makeArgumentID<T&&>();
    return *this;
  }

  void operator()(void*) const {}

public:
  TypeID const* reset() const {
    TypeID const* tmp = arg_type;
    arg_type = nullptr;
    return tmp;
  }

  mutable TypeID const* arg_type;
};


template <class ExpectT, int ID>
bool checkArg(TrackingDeleter<ID> const& d) {
  return d.arg_type && *d.arg_type == makeArgumentID<ExpectT>();
}


template <bool IsArray>
void test_sfinae() {
  typedef typename std::conditional<IsArray, A[], A>::type VT;

  { // Test that different non-reference deleter types are allowed so long
    // as they convert to each other.
    using U1 = std::unique_ptr<VT, GenericConvertingDeleter<0> >;
    using U2 = std::unique_ptr<VT, GenericConvertingDeleter<1> >;
    static_assert(std::is_constructible<U1, U2&&>::value, "");
  }
  { // Test that different non-reference deleter types are disallowed when
    // they cannot convert.
    using U1 = std::unique_ptr<VT, GenericDeleter<0> >;
    using U2 = std::unique_ptr<VT, GenericDeleter<1> >;
    static_assert(!std::is_constructible<U1, U2&&>::value, "");
  }
  { // Test that if the destination deleter is a reference type then only
    // exact matches are allowed.
    using U1 = std::unique_ptr<VT, GenericConvertingDeleter<0> const& >;
    using U2 = std::unique_ptr<VT, GenericConvertingDeleter<0> >;
    using U3 = std::unique_ptr<VT, GenericConvertingDeleter<0> &>;
    using U4 = std::unique_ptr<VT, GenericConvertingDeleter<1> >;
    using U5 = std::unique_ptr<VT, GenericConvertingDeleter<1> const&>;
    static_assert(!std::is_constructible<U1, U2&&>::value, "");
    static_assert(!std::is_constructible<U1, U3&&>::value, "");
    static_assert(!std::is_constructible<U1, U4&&>::value, "");
    static_assert(!std::is_constructible<U1, U5&&>::value, "");

    using U1C = std::unique_ptr<const VT, GenericConvertingDeleter<0> const&>;
    static_assert(std::is_nothrow_constructible<U1C, U1&&>::value, "");
  }
  { // Test that non-reference destination deleters can be constructed
    // from any source deleter type with a suitable conversion. Including
    // reference types.
    using U1 = std::unique_ptr<VT, GenericConvertingDeleter<0> >;
    using U2 = std::unique_ptr<VT, GenericConvertingDeleter<0> &>;
    using U3 = std::unique_ptr<VT, GenericConvertingDeleter<0> const &>;
    using U4 = std::unique_ptr<VT, GenericConvertingDeleter<1> >;
    using U5 = std::unique_ptr<VT, GenericConvertingDeleter<1> &>;
    using U6 = std::unique_ptr<VT, GenericConvertingDeleter<1> const&>;
    static_assert(std::is_constructible<U1, U2&&>::value, "");
    static_assert(std::is_constructible<U1, U3&&>::value, "");
    static_assert(std::is_constructible<U1, U4&&>::value, "");
    static_assert(std::is_constructible<U1, U5&&>::value, "");
    static_assert(std::is_constructible<U1, U6&&>::value, "");
  }
}


template <bool IsArray>
void test_noexcept() {
  typedef typename std::conditional<IsArray, A[], A>::type VT;
  {
    typedef std::unique_ptr<const VT> APtr;
    typedef std::unique_ptr<VT> BPtr;
    static_assert(std::is_nothrow_constructible<APtr, BPtr>::value, "");
  }
  {
    typedef std::unique_ptr<const VT, CDeleter<const VT> > APtr;
    typedef std::unique_ptr<VT, CDeleter<VT> > BPtr;
    static_assert(std::is_nothrow_constructible<APtr, BPtr>::value, "");
  }
  {
    typedef std::unique_ptr<const VT, NCDeleter<const VT>&> APtr;
    typedef std::unique_ptr<VT, NCDeleter<const VT>&> BPtr;
    static_assert(std::is_nothrow_constructible<APtr, BPtr>::value, "");
  }
  {
    typedef std::unique_ptr<const VT, const NCConstDeleter<const VT>&> APtr;
    typedef std::unique_ptr<VT, const NCConstDeleter<const VT>&> BPtr;
    static_assert(std::is_nothrow_constructible<APtr, BPtr>::value, "");
  }
}


template <bool IsArray>
void test_deleter_value_category() {
  typedef typename std::conditional<IsArray, A[], A>::type VT;
  using TD1 = TrackingDeleter<1>;
  using TD2 = TrackingDeleter<2>;
  TD1 d1;
  TD2 d2;

  { // Test non-reference deleter conversions
    using U1 = std::unique_ptr<VT, TD1 >;
    using U2 = std::unique_ptr<VT, TD2 >;
    U2 u2;
    u2.get_deleter().reset();
    U1 u1(std::move(u2));
    assert(checkArg<TD2&&>(u1.get_deleter()));
  }
  { // Test assignment from non-const ref
    using U1 = std::unique_ptr<VT, TD1 >;
    using U2 = std::unique_ptr<VT, TD2& >;
    U2 u2(nullptr, d2);
    U1 u1(std::move(u2));
    assert(checkArg<TD2&>(u1.get_deleter()));
  }
  { // Test assignment from const ref
    using U1 = std::unique_ptr<VT, TD1 >;
    using U2 = std::unique_ptr<VT, TD2 const& >;
    U2 u2(nullptr, d2);
    U1 u1(std::move(u2));
    assert(checkArg<TD2 const&>(u1.get_deleter()));
  }
}


int main(int, char**) {
  {
    test_sfinae</*IsArray*/false>();
    test_noexcept<false>();
    test_deleter_value_category<false>();
  }
  {
    test_sfinae</*IsArray*/true>();
    test_noexcept<true>();
    test_deleter_value_category<true>();
  }

  return 0;
}