// Copyright 2021, 2022 Peter Dimov.

// Distributed under the Boost Software License, Version 1.0.

// https://www.boost.org/LICENSE_1_0.txt

#include <boost/container_hash/hash.hpp>

#include <boost/core/lightweight_test.hpp>

#include <string>

#include <cstddef>

void test( std::size_t n, unsigned char ch )

{

typedef boost::hash<std::string> hash;

std::string const v( n, static_cast<char>( ch ) );

for( std::size_t i = 0; i < n * 8; ++i )

{

std::string w( v );

unsigned char ch2 = static_cast<unsigned char>( w[ i / 8 ] );

ch2 = static_cast<unsigned char>( ch2 ^ ( 1 << ( i % 8 ) ) );

w[ i / 8 ] = static_cast<char>( ch2 );

BOOST_TEST_NE( hash()( v ), hash()( w ) );

}

}

int main()

{

for( unsigned ch = 0; ch < 256; ++ch )

{

for( std::size_t n = 1; n < 32; ++n )

{

test( n, static_cast<unsigned char>( ch ) );

}

}

return boost::report_errors();

}