blob: 78b3978dde484bc4b209d88c31232e348e86ddee [file] [log] [blame]
// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#ifndef SUPPORT_VARIANT_TEST_HELPERS_H
#define SUPPORT_VARIANT_TEST_HELPERS_H
#include <type_traits>
#include <utility>
#include <cassert>
#include "test_macros.h"
#include "type_id.h"
#if TEST_STD_VER <= 14
#error This file requires C++17
#endif
// FIXME: Currently the variant<T&> tests are disabled using this macro.
#define TEST_VARIANT_HAS_NO_REFERENCES
#ifdef _LIBCPP_ENABLE_NARROWING_CONVERSIONS_IN_VARIANT
# define TEST_VARIANT_ALLOWS_NARROWING_CONVERSIONS
#endif
#ifdef TEST_VARIANT_ALLOWS_NARROWING_CONVERSIONS
constexpr bool VariantAllowsNarrowingConversions = true;
#else
constexpr bool VariantAllowsNarrowingConversions = false;
#endif
#ifndef TEST_HAS_NO_EXCEPTIONS
struct CopyThrows {
CopyThrows() = default;
CopyThrows(CopyThrows const&) { throw 42; }
CopyThrows& operator=(CopyThrows const&) { throw 42; }
};
struct MoveThrows {
static int alive;
MoveThrows() { ++alive; }
MoveThrows(MoveThrows const&) {++alive;}
MoveThrows(MoveThrows&&) { throw 42; }
MoveThrows& operator=(MoveThrows const&) { return *this; }
MoveThrows& operator=(MoveThrows&&) { throw 42; }
~MoveThrows() { --alive; }
};
int MoveThrows::alive = 0;
struct MakeEmptyT {
static int alive;
MakeEmptyT() { ++alive; }
MakeEmptyT(MakeEmptyT const&) {
++alive;
// Don't throw from the copy constructor since variant's assignment
// operator performs a copy before committing to the assignment.
}
MakeEmptyT(MakeEmptyT &&) {
throw 42;
}
MakeEmptyT& operator=(MakeEmptyT const&) {
throw 42;
}
MakeEmptyT& operator=(MakeEmptyT&&) {
throw 42;
}
~MakeEmptyT() { --alive; }
};
static_assert(std::is_swappable_v<MakeEmptyT>, ""); // required for test
int MakeEmptyT::alive = 0;
template <class Variant>
void makeEmpty(Variant& v) {
Variant v2(std::in_place_type<MakeEmptyT>);
try {
v = std::move(v2);
assert(false);
} catch (...) {
assert(v.valueless_by_exception());
}
}
#endif // TEST_HAS_NO_EXCEPTIONS
enum CallType : unsigned {
CT_None,
CT_NonConst = 1,
CT_Const = 2,
CT_LValue = 4,
CT_RValue = 8
};
inline constexpr CallType operator|(CallType LHS, CallType RHS) {
return static_cast<CallType>(static_cast<unsigned>(LHS) |
static_cast<unsigned>(RHS));
}
struct ForwardingCallObject {
template <class... Args>
ForwardingCallObject& operator()(Args&&...) & {
set_call<Args &&...>(CT_NonConst | CT_LValue);
return *this;
}
template <class... Args>
const ForwardingCallObject& operator()(Args&&...) const & {
set_call<Args &&...>(CT_Const | CT_LValue);
return *this;
}
template <class... Args>
ForwardingCallObject&& operator()(Args&&...) && {
set_call<Args &&...>(CT_NonConst | CT_RValue);
return std::move(*this);
}
template <class... Args>
const ForwardingCallObject&& operator()(Args&&...) const && {
set_call<Args &&...>(CT_Const | CT_RValue);
return std::move(*this);
}
template <class... Args> static void set_call(CallType type) {
assert(last_call_type == CT_None);
assert(last_call_args == nullptr);
last_call_type = type;
last_call_args = std::addressof(makeArgumentID<Args...>());
}
template <class... Args> static bool check_call(CallType type) {
bool result = last_call_type == type && last_call_args &&
*last_call_args == makeArgumentID<Args...>();
last_call_type = CT_None;
last_call_args = nullptr;
return result;
}
// To check explicit return type for visit<R>
constexpr operator int() const
{
return 0;
}
static CallType last_call_type;
static const TypeID *last_call_args;
};
CallType ForwardingCallObject::last_call_type = CT_None;
const TypeID *ForwardingCallObject::last_call_args = nullptr;
struct ReturnFirst {
template <class... Args> constexpr int operator()(int f, Args &&...) const {
return f;
}
};
struct ReturnArity {
template <class... Args> constexpr int operator()(Args &&...) const {
return sizeof...(Args);
}
};
#endif // SUPPORT_VARIANT_TEST_HELPERS_H