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// Copyright Catch2 Authors
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE.txt or copy at
// SPDX-License-Identifier: BSL-1.0
#ifndef CATCH_COMPARE_TRAITS_HPP_INCLUDED
#define CATCH_COMPARE_TRAITS_HPP_INCLUDED
#include <catch2/internal/catch_void_type.hpp>
#include <type_traits>
namespace Catch {
namespace Detail {
#if defined( __GNUC__ ) && !defined( __clang__ )
# pragma GCC diagnostic push
// GCC likes to complain about comparing bool with 0, in the decltype()
// that defines the comparable traits below.
# pragma GCC diagnostic ignored "-Wbool-compare"
// "ordered comparison of pointer with integer zero" same as above,
// but it does not have a separate warning flag to suppress
# pragma GCC diagnostic ignored "-Wextra"
// Did you know that comparing floats with `0` directly
// is super-duper dangerous in unevaluated context?
# pragma GCC diagnostic ignored "-Wfloat-equal"
#endif
#if defined( __clang__ )
# pragma clang diagnostic push
// Did you know that comparing floats with `0` directly
// is super-duper dangerous in unevaluated context?
# pragma clang diagnostic ignored "-Wfloat-equal"
#endif
#define CATCH_DEFINE_COMPARABLE_TRAIT( id, op ) \
template <typename, typename, typename = void> \
struct is_##id##_comparable : std::false_type {}; \
template <typename T, typename U> \
struct is_##id##_comparable< \
T, \
U, \
void_t<decltype( std::declval<T>() op std::declval<U>() )>> \
: std::true_type {}; \
template <typename, typename = void> \
struct is_##id##_0_comparable : std::false_type {}; \
template <typename T> \
struct is_##id##_0_comparable<T, \
void_t<decltype( std::declval<T>() op 0 )>> \
: std::true_type {};
// We need all 6 pre-spaceship comparison ops: <, <=, >, >=, ==, !=
CATCH_DEFINE_COMPARABLE_TRAIT( lt, < )
CATCH_DEFINE_COMPARABLE_TRAIT( le, <= )
CATCH_DEFINE_COMPARABLE_TRAIT( gt, > )
CATCH_DEFINE_COMPARABLE_TRAIT( ge, >= )
CATCH_DEFINE_COMPARABLE_TRAIT( eq, == )
CATCH_DEFINE_COMPARABLE_TRAIT( ne, != )
#undef CATCH_DEFINE_COMPARABLE_TRAIT
#if defined( __GNUC__ ) && !defined( __clang__ )
# pragma GCC diagnostic pop
#endif
#if defined( __clang__ )
# pragma clang diagnostic pop
#endif
} // namespace Detail
} // namespace Catch
#endif // CATCH_COMPARE_TRAITS_HPP_INCLUDED