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//===----------------------------------------------------------------------===//
//
// 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
// type_traits
// is_nothrow_invocable
#include <type_traits>
#include <functional>
#include <vector>
#include "test_macros.h"
struct Tag {};
struct Implicit {
Implicit(int) noexcept {}
};
struct ThrowsImplicit {
ThrowsImplicit(int) {}
};
struct Explicit {
explicit Explicit(int) noexcept {}
};
template <bool IsNoexcept, class Ret, class... Args>
struct CallObject {
Ret operator()(Args&&...) const noexcept(IsNoexcept);
};
struct Sink {
template <class... Args>
void operator()(Args&&...) const noexcept {}
};
template <class Fn, class... Args>
constexpr bool throws_invocable() {
return std::is_invocable<Fn, Args...>::value &&
!std::is_nothrow_invocable<Fn, Args...>::value;
}
template <class Ret, class Fn, class... Args>
constexpr bool throws_invocable_r() {
return std::is_invocable_r<Ret, Fn, Args...>::value &&
!std::is_nothrow_invocable_r<Ret, Fn, Args...>::value;
}
void test_noexcept_function_pointers() {
struct Dummy {
void foo() noexcept {}
static void bar() noexcept {}
};
// Check that PMF's and function pointers actually work and that
// is_nothrow_invocable returns true for noexcept PMF's and function
// pointers.
static_assert(std::is_nothrow_invocable<decltype(&Dummy::foo), Dummy&>::value, "");
static_assert(std::is_nothrow_invocable<decltype(&Dummy::bar)>::value, "");
}
int main(int, char**) {
using AbominableFunc = void(...) const noexcept;
// Non-callable things
{
static_assert(!std::is_nothrow_invocable<void>::value, "");
static_assert(!std::is_nothrow_invocable<const void>::value, "");
static_assert(!std::is_nothrow_invocable<volatile void>::value, "");
static_assert(!std::is_nothrow_invocable<const volatile void>::value, "");
static_assert(!std::is_nothrow_invocable<std::nullptr_t>::value, "");
static_assert(!std::is_nothrow_invocable<int>::value, "");
static_assert(!std::is_nothrow_invocable<double>::value, "");
static_assert(!std::is_nothrow_invocable<int[]>::value, "");
static_assert(!std::is_nothrow_invocable<int[3]>::value, "");
static_assert(!std::is_nothrow_invocable<int*>::value, "");
static_assert(!std::is_nothrow_invocable<const int*>::value, "");
static_assert(!std::is_nothrow_invocable<int const*>::value, "");
static_assert(!std::is_nothrow_invocable<int&>::value, "");
static_assert(!std::is_nothrow_invocable<const int&>::value, "");
static_assert(!std::is_nothrow_invocable<int&&>::value, "");
static_assert(!std::is_nothrow_invocable<int, std::vector<int> >::value,
"");
static_assert(!std::is_nothrow_invocable<int, std::vector<int*> >::value,
"");
static_assert(!std::is_nothrow_invocable<int, std::vector<int**> >::value,
"");
static_assert(!std::is_nothrow_invocable<AbominableFunc>::value, "");
// with parameters
static_assert(!std::is_nothrow_invocable<int, int>::value, "");
static_assert(!std::is_nothrow_invocable<int, double, float>::value, "");
static_assert(!std::is_nothrow_invocable<int, char, float, double>::value,
"");
static_assert(!std::is_nothrow_invocable<Sink, AbominableFunc>::value, "");
static_assert(!std::is_nothrow_invocable<Sink, void>::value, "");
static_assert(!std::is_nothrow_invocable<Sink, const volatile void>::value,
"");
static_assert(!std::is_nothrow_invocable_r<int, void>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, const void>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, volatile void>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, const volatile void>::value,
"");
static_assert(!std::is_nothrow_invocable_r<int, std::nullptr_t>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, int>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, double>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, int[]>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, int[3]>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, int*>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, const int*>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, int const*>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, int&>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, const int&>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, int&&>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, std::vector<int> >::value,
"");
static_assert(!std::is_nothrow_invocable_r<int, std::vector<int*> >::value,
"");
static_assert(!std::is_nothrow_invocable_r<int, std::vector<int**> >::value,
"");
static_assert(!std::is_nothrow_invocable_r<void, AbominableFunc>::value,
"");
// with parameters
static_assert(!std::is_nothrow_invocable_r<int, int, int>::value, "");
static_assert(!std::is_nothrow_invocable_r<int, int, double, float>::value,
"");
static_assert(
!std::is_nothrow_invocable_r<int, int, char, float, double>::value, "");
static_assert(
!std::is_nothrow_invocable_r<void, Sink, AbominableFunc>::value, "");
static_assert(!std::is_nothrow_invocable_r<void, Sink, void>::value, "");
static_assert(
!std::is_nothrow_invocable_r<void, Sink, const volatile void>::value,
"");
}
{
// Check that the conversion to the return type is properly checked
using Fn = CallObject<true, int>;
static_assert(std::is_nothrow_invocable_r<Implicit, Fn>::value, "");
static_assert(std::is_nothrow_invocable_r<double, Fn>::value, "");
static_assert(std::is_nothrow_invocable_r<const volatile void, Fn>::value,
"");
static_assert(throws_invocable_r<ThrowsImplicit, Fn>(), "");
static_assert(!std::is_nothrow_invocable<Fn(), Explicit>(), "");
}
{
// Check that the conversion to the parameters is properly checked
using Fn = CallObject<true, void, const Implicit&, const ThrowsImplicit&>;
static_assert(
std::is_nothrow_invocable<Fn, Implicit&, ThrowsImplicit&>::value, "");
static_assert(std::is_nothrow_invocable<Fn, int, ThrowsImplicit&>::value,
"");
static_assert(throws_invocable<Fn, int, int>(), "");
static_assert(!std::is_nothrow_invocable<Fn>::value, "");
}
{
// Check that the noexcept-ness of function objects is checked.
using Fn = CallObject<true, void>;
using Fn2 = CallObject<false, void>;
static_assert(std::is_nothrow_invocable<Fn>::value, "");
static_assert(throws_invocable<Fn2>(), "");
}
{
// Check that PMD derefs are noexcept
using Fn = int(Tag::*);
static_assert(std::is_nothrow_invocable<Fn, Tag&>::value, "");
static_assert(std::is_nothrow_invocable_r<Implicit, Fn, Tag&>::value, "");
static_assert(throws_invocable_r<ThrowsImplicit, Fn, Tag&>(), "");
}
{
// Check that it's fine if the result type is non-moveable.
struct CantMove {
CantMove() = default;
CantMove(CantMove&&) = delete;
};
static_assert(!std::is_move_constructible_v<CantMove>);
static_assert(!std::is_copy_constructible_v<CantMove>);
using Fn = CantMove() noexcept;
static_assert(std::is_nothrow_invocable_r<CantMove, Fn>::value);
static_assert(!std::is_nothrow_invocable_r<CantMove, Fn, int>::value);
static_assert(std::is_nothrow_invocable_r_v<CantMove, Fn>);
static_assert(!std::is_nothrow_invocable_r_v<CantMove, Fn, int>);
}
{
// Check for is_nothrow_invocable_v
using Fn = CallObject<true, int>;
static_assert(std::is_nothrow_invocable_v<Fn>, "");
static_assert(!std::is_nothrow_invocable_v<Fn, int>, "");
}
{
// Check for is_nothrow_invocable_r_v
using Fn = CallObject<true, int>;
static_assert(std::is_nothrow_invocable_r_v<void, Fn>, "");
static_assert(!std::is_nothrow_invocable_r_v<int, Fn, int>, "");
}
test_noexcept_function_pointers();
return 0;
}
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