boost_unordered/test/helpers/generators.hpp

// Copyright 2005-2009 Daniel James.
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

// This uses std::rand to generate random values for tests.
// Which is not good as different platforms will be running different tests.
// It would be much better to use Boost.Random, but it doesn't
// support all the compilers that I want to test on.

#if !defined(BOOST_UNORDERED_TEST_HELPERS_GENERATORS_HEADER)
#define BOOST_UNORDERED_TEST_HELPERS_GENERATORS_HEADER

#include <string>
#include <utility>
#include <stdexcept>
#include <cstdlib>
#include <boost/type_traits/add_const.hpp>
#include "./fwd.hpp"

namespace test
{
    struct seed_t {
        seed_t(unsigned int x) {
            using namespace std;
            srand(x);
        }
    };

    std::size_t random_value(std::size_t max) {
        using namespace std;
        return static_cast<std::size_t>(rand()) % max;
    }

    inline int generate(int const*, random_generator g)
    {
        using namespace std;
        int value = rand();
        if (g == limited_range) { value = value % 100; }
        return value;
    }

    inline char generate(char const*, random_generator)
    {
        using namespace std;
        return static_cast<char>((rand() >> 1) % (128-32) + 32);
    }

    inline signed char generate(signed char const*, random_generator)
    {
        using namespace std;
        return static_cast<signed char>(rand());
    }

    inline std::string generate(std::string const*, random_generator g)
    {
        using namespace std;

        char* char_ptr = 0;

        std::string result;

        if (g == limited_range) {
            std::size_t length = test::random_value(2) + 2;

            char const* strings[] = { "'vZh(3~ms", "%m", "_Y%U", "N'Y", "4,J_J" };
            for (std::size_t i = 0; i < length; ++i) {
                result += strings[random_value(sizeof(strings) / sizeof(strings[0]))];
            }
        }
        else {
            std::size_t length = test::random_value(10) + 1;
            for (std::size_t i = 0; i < length; ++i) {
                result += generate(char_ptr, g);
            }
        }

        return result;
    }

    float generate(float const*, random_generator g)
    {
        using namespace std;
        int x = 0;
        int value = generate(&x, g);
        return (float) value / (float) RAND_MAX;
    }
}

#endif