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// Copyright 2017, 2018, 2024, 2025 Peter Dimov
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt
#include <boost/hash2/get_integral_result.hpp>
#include <boost/hash2/fnv1a.hpp>
#include <boost/core/lightweight_test.hpp>
#include <cstdint>
using boost::hash2::fnv1a_64;
using boost::hash2::get_integral_result;
template<class R> struct fnv1a_x: private fnv1a_64
{
using result_type = R;
result_type result()
{
return get_integral_result<R>( static_cast<fnv1a_64&>( *this ) );
}
};
int main()
{
// 1 -> 2
{
fnv1a_x<std::uint8_t> h1;
std::uint16_t r1 = get_integral_result<std::int16_t>( h1 );
fnv1a_x<std::uint8_t> h2;
std::uint16_t r2 = 0;
r2 += static_cast<std::uint16_t>( h2.result() ) << 0;
r2 += static_cast<std::uint16_t>( h2.result() ) << 8;
BOOST_TEST_EQ( static_cast<std::uint16_t>( r1 ), r2 );
}
// 1 -> 4
{
fnv1a_x<std::uint8_t> h1;
std::uint32_t r1 = get_integral_result<std::int32_t>( h1 );
fnv1a_x<std::uint8_t> h2;
std::uint32_t r2 = 0;
r2 += static_cast<std::uint32_t>( h2.result() ) << 0;
r2 += static_cast<std::uint32_t>( h2.result() ) << 8;
r2 += static_cast<std::uint32_t>( h2.result() ) << 16;
r2 += static_cast<std::uint32_t>( h2.result() ) << 24;
BOOST_TEST_EQ( static_cast<std::uint32_t>( r1 ), r2 );
}
// 1 -> 8
{
fnv1a_x<std::uint8_t> h1;
std::uint64_t r1 = get_integral_result<std::int64_t>( h1 );
fnv1a_x<std::uint8_t> h2;
std::uint64_t r2 = 0;
r2 += static_cast<std::uint64_t>( h2.result() ) << 0;
r2 += static_cast<std::uint64_t>( h2.result() ) << 8;
r2 += static_cast<std::uint64_t>( h2.result() ) << 16;
r2 += static_cast<std::uint64_t>( h2.result() ) << 24;
r2 += static_cast<std::uint64_t>( h2.result() ) << 32;
r2 += static_cast<std::uint64_t>( h2.result() ) << 40;
r2 += static_cast<std::uint64_t>( h2.result() ) << 48;
r2 += static_cast<std::uint64_t>( h2.result() ) << 56;
BOOST_TEST_EQ( static_cast<std::uint64_t>( r1 ), r2 );
}
// 2 -> 4
{
fnv1a_x<std::uint16_t> h1;
std::uint32_t r1 = get_integral_result<std::int32_t>( h1 );
fnv1a_x<std::uint16_t> h2;
std::uint32_t r2 = 0;
r2 += static_cast<std::uint32_t>( h2.result() ) << 0;
r2 += static_cast<std::uint32_t>( h2.result() ) << 16;
BOOST_TEST_EQ( static_cast<std::uint32_t>( r1 ), r2 );
}
// 2 -> 8
{
fnv1a_x<std::uint16_t> h1;
std::uint64_t r1 = get_integral_result<std::int64_t>( h1 );
fnv1a_x<std::uint16_t> h2;
std::uint64_t r2 = 0;
r2 += static_cast<std::uint64_t>( h2.result() ) << 0;
r2 += static_cast<std::uint64_t>( h2.result() ) << 16;
r2 += static_cast<std::uint64_t>( h2.result() ) << 32;
r2 += static_cast<std::uint64_t>( h2.result() ) << 48;
BOOST_TEST_EQ( static_cast<std::uint64_t>( r1 ), r2 );
}
// 4 -> 8
{
fnv1a_x<std::uint32_t> h1;
std::uint64_t r1 = get_integral_result<std::int64_t>( h1 );
fnv1a_x<std::uint32_t> h2;
std::uint64_t r2 = 0;
r2 += static_cast<std::uint64_t>( h2.result() ) << 0;
r2 += static_cast<std::uint64_t>( h2.result() ) << 32;
BOOST_TEST_EQ( static_cast<std::uint64_t>( r1 ), r2 );
}
return boost::report_errors();
}
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