84742cd867
[P2231R1](https://wg21.link/P2231R1) "Missing `constexpr` in `std::optional` and `std::variant`" was accepted as a C++20 Defect Report, not a C++17 Defect Report. Accordingly, `test_empty_emplace()` and `check_reset()` should be marked as `TEST_CONSTEXPR_CXX20`. Note that their `static_assert`s are properly guarded:4ce65423be/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/emplace.pass.cpp (L270-L272)4ce65423be/libcxx/test/std/utilities/optional/optional.object/optional.object.mod/reset.pass.cpp (L53-L55)Found while running libc++'s tests with MSVC's STL, as we activate our `constexpr` here for C++20 and above.
74 lines
1.6 KiB
C++
74 lines
1.6 KiB
C++
//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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// UNSUPPORTED: c++03, c++11, c++14
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// <optional>
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// void reset() noexcept;
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#include <optional>
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#include <type_traits>
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#include <cassert>
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#include "test_macros.h"
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using std::optional;
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struct X
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{
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static bool dtor_called;
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X() = default;
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X(const X&) = default;
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X& operator=(const X&) = default;
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~X() {dtor_called = true;}
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};
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bool X::dtor_called = false;
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TEST_CONSTEXPR_CXX20 bool check_reset() {
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{
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optional<int> opt;
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static_assert(noexcept(opt.reset()) == true, "");
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opt.reset();
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assert(static_cast<bool>(opt) == false);
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}
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{
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optional<int> opt(3);
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opt.reset();
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assert(static_cast<bool>(opt) == false);
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}
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return true;
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}
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int main(int, char**)
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{
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check_reset();
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#if TEST_STD_VER >= 20
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static_assert(check_reset());
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#endif
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{
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optional<X> opt;
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static_assert(noexcept(opt.reset()) == true, "");
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assert(X::dtor_called == false);
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opt.reset();
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assert(X::dtor_called == false);
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assert(static_cast<bool>(opt) == false);
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}
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{
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optional<X> opt(X{});
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X::dtor_called = false;
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opt.reset();
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assert(X::dtor_called == true);
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assert(static_cast<bool>(opt) == false);
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X::dtor_called = false;
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}
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return 0;
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}
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