libcxx/test/std/thread/futures/futures.shared_future/copy_assign.pass.cpp

   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: no-threads
  10 // UNSUPPORTED: c++03
  11
  12 // <future>
  13
  14 // class shared_future<R>
  15
  16 // shared_future& operator=(const shared_future& rhs);
  17 // noexcept in C++17
  18
  19 #include <future>
  20 #include <cassert>
  21
  22 #include "test_macros.h"
  23
  24 int main(int, char**)
  25 {
  26     {
  27         typedef int T;
  28         std::promise<T> p;
  29         std::shared_future<T> f0 = p.get_future();
  30         std::shared_future<T> f;
  31         f = f0;
  32 #if TEST_STD_VER > 14
  33         static_assert(noexcept(f = f0), "" );
  34 #endif
  35         assert(f0.valid());
  36         assert(f.valid());
  37     }
  38     {
  39         typedef int T;
  40         std::shared_future<T> f0;
  41         std::shared_future<T> f;
  42         f = f0;
  43         assert(!f0.valid());
  44         assert(!f.valid());
  45     }
  46     {
  47         typedef int& T;
  48         std::promise<T> p;
  49         std::shared_future<T> f0 = p.get_future();
  50         std::shared_future<T> f;
  51         f = f0;
  52         assert(f0.valid());
  53         assert(f.valid());
  54     }
  55     {
  56         typedef int& T;
  57         std::shared_future<T> f0;
  58         std::shared_future<T> f;
  59         f = f0;
  60         assert(!f0.valid());
  61         assert(!f.valid());
  62     }
  63     {
  64         typedef void T;
  65         std::promise<T> p;
  66         std::shared_future<T> f0 = p.get_future();
  67         std::shared_future<T> f;
  68         f = f0;
  69         assert(f0.valid());
  70         assert(f.valid());
  71     }
  72     {
  73         typedef void T;
  74         std::shared_future<T> f0;
  75         std::shared_future<T> f;
  76         f = f0;
  77         assert(!f0.valid());
  78         assert(!f.valid());
  79     }
  80
  81   return 0;
  82 }