cast_to_int.php

<?php
/**
 * Random_* Compatibility Library
 * for using the new PHP 7 random_* API in PHP 5 projects
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

if (!is_callable('RandomCompat_intval')) {
    
    /**
     * Cast to an integer if we can, safely.
     * 
     * If you pass it a float in the range (~PHP_INT_MAX, PHP_INT_MAX)
     * (non-inclusive), it will sanely cast it to an int. If you it's equal to
     * ~PHP_INT_MAX or PHP_INT_MAX, we let it fail as not an integer. Floats 
     * lose precision, so the <= and => operators might accidentally let a float
     * through.
     * 
     * @param int|float $number    The number we want to convert to an int
     * @param bool      $fail_open Set to true to not throw an exception
     * 
     * @return float|int
     * @psalm-suppress InvalidReturnType
     *
     * @throws TypeError
     */
    function RandomCompat_intval($number, $fail_open = false)
    {
        if (is_int($number) || is_float($number)) {
            $number += 0;
        } elseif (is_numeric($number)) {
            /** @psalm-suppress InvalidOperand */
            $number += 0;
        }
        /** @var int|float $number */

        if (
            is_float($number)
                &&
            $number > ~PHP_INT_MAX
                &&
            $number < PHP_INT_MAX
        ) {
            $number = (int) $number;
        }

        if (is_int($number)) {
            return (int) $number;
        } elseif (!$fail_open) {
            throw new TypeError(
                'Expected an integer.'
            );
        }
        return $number;
    }
}