Eric Fiselier | 8d5cbd7 | 2016-04-20 00:14:32 +0000 | [diff] [blame] | 1 | //===----------------------------------------------------------------------===// |
| 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
| 5 | // This file is dual licensed under the MIT and the University of Illinois Open |
| 6 | // Source Licenses. See LICENSE.TXT for details. |
| 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
| 9 | |
| 10 | // UNSUPPORTED: c++98, c++03, c++11, c++14 |
| 11 | |
| 12 | // type_traits |
| 13 | |
| 14 | // is_nothrow_callable |
| 15 | |
| 16 | #include <type_traits> |
| 17 | #include <functional> |
| 18 | |
| 19 | #include "test_macros.h" |
| 20 | |
| 21 | struct Tag {}; |
| 22 | |
| 23 | struct Implicit { |
| 24 | Implicit(int) noexcept {} |
| 25 | }; |
| 26 | |
| 27 | struct ThrowsImplicit { |
| 28 | ThrowsImplicit(int) {} |
| 29 | }; |
| 30 | |
| 31 | struct Explicit { |
| 32 | explicit Explicit(int) noexcept {} |
| 33 | }; |
| 34 | |
| 35 | template <bool IsNoexcept, class Ret, class ...Args> |
| 36 | struct CallObject { |
| 37 | Ret operator()(Args&&...) const noexcept(IsNoexcept); |
| 38 | }; |
| 39 | |
| 40 | template <class Fn> |
| 41 | constexpr bool throws_callable() { |
| 42 | return std::is_callable<Fn>::value && |
| 43 | !std::is_nothrow_callable<Fn>::value; |
| 44 | } |
| 45 | |
| 46 | template <class Fn, class Ret> |
| 47 | constexpr bool throws_callable() { |
| 48 | return std::is_callable<Fn, Ret>::value && |
| 49 | !std::is_nothrow_callable<Fn, Ret>::value; |
| 50 | } |
| 51 | |
| 52 | // FIXME(EricWF) Don't test the where noexcept is *not* part of the type system |
| 53 | // once implementations have caught up. |
| 54 | void test_noexcept_function_pointers() |
| 55 | { |
Eric Fiselier | ce24f96 | 2016-04-28 02:18:48 +0000 | [diff] [blame] | 56 | struct Dummy { void foo() noexcept {} static void bar() noexcept {} }; |
Eric Fiselier | 8d5cbd7 | 2016-04-20 00:14:32 +0000 | [diff] [blame] | 57 | #if !defined(__cpp_noexcept_function_type) |
| 58 | { |
| 59 | // Check that PMF's and function pointers *work*. is_nothrow_callable will always |
| 60 | // return false because 'noexcept' is not part of the function type. |
| 61 | static_assert(throws_callable<decltype(&Dummy::foo)(Dummy&)>()); |
| 62 | static_assert(throws_callable<decltype(&Dummy::bar)()>()); |
| 63 | } |
| 64 | #else |
| 65 | { |
| 66 | // Check that PMF's and function pointers actually work and that |
| 67 | // is_nothrow_callable returns true for noexcept PMF's and function |
| 68 | // pointers. |
| 69 | static_assert(std::is_nothrow_callable<decltype(&Dummy::foo)(Dummy&)>::value); |
| 70 | static_assert(std::is_nothrow_callable<decltype(&Dummy::bar)()>::value); |
| 71 | } |
| 72 | #endif |
| 73 | } |
| 74 | |
| 75 | int main() |
| 76 | { |
| 77 | { |
| 78 | // Check that the conversion to the return type is properly checked |
| 79 | using Fn = CallObject<true, int>; |
| 80 | static_assert(std::is_nothrow_callable<Fn(), Implicit>::value); |
| 81 | static_assert(std::is_nothrow_callable<Fn(), double>::value); |
| 82 | static_assert(std::is_nothrow_callable<Fn(), const volatile void>::value); |
| 83 | static_assert(throws_callable<Fn(), ThrowsImplicit>()); |
| 84 | static_assert(!std::is_nothrow_callable<Fn(), Explicit>()); |
| 85 | } |
| 86 | { |
| 87 | // Check that the conversion to the parameters is properly checked |
| 88 | using Fn = CallObject<true, void, const Implicit&, const ThrowsImplicit&>; |
| 89 | static_assert(std::is_nothrow_callable<Fn(Implicit&, ThrowsImplicit&)>::value); |
| 90 | static_assert(std::is_nothrow_callable<Fn(int, ThrowsImplicit&)>::value); |
| 91 | static_assert(throws_callable<Fn(int, int)>()); |
| 92 | static_assert(!std::is_nothrow_callable<Fn()>::value); |
| 93 | } |
| 94 | { |
| 95 | // Check that the noexcept-ness of function objects is checked. |
| 96 | using Fn = CallObject<true, void>; |
| 97 | using Fn2 = CallObject<false, void>; |
| 98 | static_assert(std::is_nothrow_callable<Fn()>::value); |
| 99 | static_assert(throws_callable<Fn2()>()); |
| 100 | } |
| 101 | { |
| 102 | // Check that PMD derefs are noexcept |
| 103 | using Fn = int (Tag::*); |
| 104 | static_assert(std::is_nothrow_callable<Fn(Tag&)>::value); |
| 105 | static_assert(std::is_nothrow_callable<Fn(Tag&), Implicit>::value); |
| 106 | static_assert(throws_callable<Fn(Tag&), ThrowsImplicit>()); |
| 107 | } |
| 108 | { |
| 109 | // Check for is_nothrow_callable_v |
| 110 | using Fn = CallObject<true, int>; |
| 111 | static_assert(std::is_nothrow_callable_v<Fn()>); |
| 112 | static_assert(!std::is_nothrow_callable_v<Fn(int)>); |
| 113 | } |
| 114 | test_noexcept_function_pointers(); |
| 115 | } |