libcxx/test/std/thread/thread.stoptoken/stopsource/assign.copy.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: libcpp-has-no-experimental-stop_token
  11 // UNSUPPORTED: c++03, c++11, c++14, c++17
  12 // XFAIL: availability-synchronization_library-missing
  13
  14 // stop_source& operator=(const stop_source& rhs) noexcept;
  15
  16 #include <cassert>
  17 #include <concepts>
  18 #include <stop_token>
  19 #include <type_traits>
  20
  21 #include "test_macros.h"
  22
  23 static_assert(std::is_nothrow_copy_assignable_v<std::stop_source>);
  24
  25 int main(int, char**) {
  26   // have two different states
  27   {
  28     std::stop_source ss1;
  29     std::stop_source ss2;
  30
  31     assert(ss1 != ss2);
  32
  33     ss2.request_stop();
  34
  35     assert(!ss1.stop_requested());
  36     assert(ss2.stop_requested());
  37
  38     std::same_as<std::stop_source&> decltype(auto) ref = ss1 = ss2;
  39     assert(&ref == &ss1);
  40
  41     assert(ss1 == ss2);
  42     assert(ss1.stop_requested());
  43     assert(ss2.stop_requested());
  44   }
  45
  46   // this has no state
  47   {
  48     std::stop_source ss1{std::nostopstate};
  49     std::stop_source ss2;
  50
  51     assert(ss1 != ss2);
  52
  53     ss2.request_stop();
  54
  55     assert(!ss1.stop_requested());
  56     assert(!ss1.stop_possible());
  57     assert(ss2.stop_requested());
  58     assert(ss2.stop_possible());
  59
  60     std::same_as<std::stop_source&> decltype(auto) ref = ss1 = ss2;
  61     assert(&ref == &ss1);
  62
  63     assert(ss1 == ss2);
  64     assert(ss1.stop_requested());
  65     assert(ss1.stop_possible());
  66     assert(ss2.stop_requested());
  67     assert(ss2.stop_possible());
  68   }
  69
  70   // other has no state
  71   {
  72     std::stop_source ss1;
  73     std::stop_source ss2{std::nostopstate};
  74
  75     assert(ss1 != ss2);
  76
  77     ss1.request_stop();
  78
  79     assert(ss1.stop_requested());
  80     assert(ss1.stop_possible());
  81     assert(!ss2.stop_requested());
  82     assert(!ss2.stop_possible());
  83
  84     std::same_as<std::stop_source&> decltype(auto) ref = ss1 = ss2;
  85     assert(&ref == &ss1);
  86
  87     assert(ss1 == ss2);
  88     assert(!ss1.stop_requested());
  89     assert(!ss1.stop_possible());
  90     assert(!ss2.stop_requested());
  91     assert(!ss2.stop_possible());
  92   }
  93
  94   // both no state
  95   {
  96     std::stop_source ss1{std::nostopstate};
  97     std::stop_source ss2{std::nostopstate};
  98
  99     assert(ss1 == ss2);
 100
 101     assert(!ss1.stop_requested());
 102     assert(!ss1.stop_possible());
 103     assert(!ss2.stop_requested());
 104     assert(!ss2.stop_possible());
 105
 106     std::same_as<std::stop_source&> decltype(auto) ref = ss1 = ss2;
 107     assert(&ref == &ss1);
 108
 109     assert(ss1 == ss2);
 110     assert(!ss1.stop_requested());
 111     assert(!ss1.stop_possible());
 112     assert(!ss2.stop_requested());
 113     assert(!ss2.stop_possible());
 114   }
 115
 116   // self assignment
 117   {
 118     std::stop_source ss;
 119     auto& self = ss;
 120
 121     assert(!ss.stop_requested());
 122
 123     std::same_as<std::stop_source&> decltype(auto) ref = ss = self;
 124     assert(&ref == &ss);
 125
 126     assert(!ss.stop_requested());
 127
 128     ss.request_stop();
 129     assert(ss.stop_requested());
 130   }
 131
 132   return 0;
 133 }