libcxx/test/std/thread/futures/futures.future_error/what.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
  11 // LWG 2056 changed the values of future_errc, so if we're using new headers
  12 // with an old library we'll get incorrect messages.
  13 //
  14 // XFAIL: stdlib=apple-libc++ && target={{.+}}-apple-macosx10.{{9|10|11}}
  15
  16 // VC Runtime's std::exception::what() method is not marked as noexcept, so
  17 // this fails.
  18 // UNSUPPORTED: target=x86_64-pc-windows-msvc
  19
  20 // <future>
  21 //
  22 // class future_error
  23 //
  24 // const char* what() const noexcept;
  25
  26 #include <cassert>
  27 #include <future>
  28 #include <string_view>
  29 #include <utility>
  30
  31 #include "test_macros.h"
  32
  33 int main(int, char**) {
  34   ASSERT_NOEXCEPT(std::declval<std::future_error const&>().what());
  35   ASSERT_SAME_TYPE(decltype(std::declval<std::future_error const&>().what()), char const*);
  36
  37   // Before C++17, we can't construct std::future_error directly in a standards-conforming way
  38 #if TEST_STD_VER >= 17
  39   {
  40     std::future_error const f(std::future_errc::broken_promise);
  41     [[maybe_unused]] char const* what = f.what();
  42     LIBCPP_ASSERT(what == std::string_view{"The associated promise has been destructed prior "
  43                                            "to the associated state becoming ready."});
  44   }
  45   {
  46     std::future_error f(std::future_errc::future_already_retrieved);
  47     [[maybe_unused]] char const* what = f.what();
  48     LIBCPP_ASSERT(what == std::string_view{"The future has already been retrieved from "
  49                                            "the promise or packaged_task."});
  50   }
  51   {
  52     std::future_error f(std::future_errc::promise_already_satisfied);
  53     [[maybe_unused]] char const* what = f.what();
  54     LIBCPP_ASSERT(what == std::string_view{"The state of the promise has already been set."});
  55   }
  56   {
  57     std::future_error f(std::future_errc::no_state);
  58     [[maybe_unused]] char const* what = f.what();
  59     LIBCPP_ASSERT(what == std::string_view{"Operation not permitted on an object without "
  60                                            "an associated state."});
  61   }
  62 #endif
  63
  64   return 0;
  65 }