1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // UNSUPPORTED: c++03, c++11, c++14, c++17
10 // UNSUPPORTED: ubsan
11 
12 // <coroutine>
13 // struct noop_coroutine_promise;
14 // using noop_coroutine_handle = coroutine_handle<noop_coroutine_promise>;
15 // noop_coroutine_handle noop_coroutine() noexcept;
16 
17 #include <coroutine>
18 #include <cassert>
19 #include <type_traits>
20 
21 #include "test_macros.h"
22 
23 static_assert(std::is_same<std::coroutine_handle<std::noop_coroutine_promise>, std::noop_coroutine_handle>::value, "");
24 static_assert(std::is_same<decltype(std::noop_coroutine()), std::noop_coroutine_handle>::value, "");
25 
26 // template <> struct coroutine_handle<noop_coroutine_promise> : coroutine_handle<>
27 // {
28 // // [coroutine.handle.noop.observers], observers
29 // constexpr explicit operator bool() const noexcept;
30 // constexpr bool done() const noexcept;
31 
32 // // [coroutine.handle.noop.resumption], resumption
33 // constexpr void operator()() const noexcept;
34 // constexpr void resume() const noexcept;
35 // constexpr void destroy() const noexcept;
36 
37 // // [coroutine.handle.noop.promise], promise access
38 // noop_coroutine_promise& promise() const noexcept;
39 
40 // // [coroutine.handle.noop.address], address
41 // constexpr void* address() const noexcept;
42 
main(int,char **)43 int main(int, char**)
44 {
45   auto h = std::noop_coroutine();
46   std::coroutine_handle<> base = h;
47 
48   assert(h);
49   assert(base);
50 
51   assert(!h.done());
52   assert(!base.done());
53 
54   h.resume();
55   h.destroy();
56   h();
57   static_assert(h, "");
58   static_assert(h.done() == false, "");
59 
60   // [coroutine.handle.noop.resumption]p2
61   // Remarks: If noop_coroutine_handle is converted to
62   // coroutine_handle<>, calls to operator(), resume and
63   // destroy on that handle will also have no observable
64   // effects.
65   base.resume();
66   base.destroy();
67   base();
68   assert(base);
69   assert(base.done() == false);
70 
71   TEST_IGNORE_NODISCARD h.promise();
72   assert(h.address() == base.address());
73   assert(h == base);
74   assert(h.address() != nullptr);
75   assert(std::coroutine_handle<>::from_address(h.address()) == base);
76 
77   return 0;
78 }
79