type-tools-php

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<?php
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declare(strict_types=1);
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namespace Smoren\TypeTools;
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use Closure;
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use Generator;
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/**
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 * Tool for extracting unique IDs and hashes of any PHP variables and data structures.
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 */
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class UniqueExtractor
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{
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    /**
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     * Returns unique ID string of given variable by its value and type.
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     *
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     * If $strict is true:
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     *  - scalars: result is unique strictly by type;
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     *  - objects: result is unique by instance;
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     *  - arrays: result is unique by serialized value;
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     *  - resources: result is unique by instance.
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     *
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     * If $strict is false:
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     *  - scalars: result is unique by value;
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     *  - objects: result is unique by serialized value;
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     *  - arrays: result is unique by serialized value.
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     *  - resources: result is unique by instance.
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     *
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     * @param mixed $var
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     * @param bool $strict
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     *
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     * @return string
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     */
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    public static function getString($var, bool $strict): string
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    {
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        switch (true) {
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            case is_array($var):
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                return 'array_'.serialize($var);
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            case is_resource($var):
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                return 'resource_'.get_resource_type($var).'_'.(string)$var;
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            case $var instanceof Generator:
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                return 'generator_'.spl_object_id($var);
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            case $var instanceof Closure:
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                return 'closure_'.spl_object_id($var);
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            case is_object($var):
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                return 'object_'.($strict ? spl_object_id($var) : serialize($var));
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            case gettype($var) === 'boolean':
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                return 'boolean_'.(int)$var;
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            case $strict:
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                return gettype($var).'_'.$var;
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            case !$var:
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                return 'boolean_0';
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            case strval($var) === '1':
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                return 'boolean_1';
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            case is_numeric($var):
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                return 'numeric_'.(float)$var;
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            default:
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                return 'scalar_'.$var;
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        }
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    }
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    /**
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     * Returns unique md5 hash string of given variable by its value and type.
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     *
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     * If $strict is true:
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     *  - scalars: result is unique strictly by type;
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     *  - objects: result is unique by instance;
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     *  - arrays: result is unique by serialized value.
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     *
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     * If $strict is false:
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     *  - scalars: result is unique by value;
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     *  - objects: result is unique by serialized value;
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     *  - arrays: result is unique by serialized value.
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     *
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     * @param mixed $var
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     * @param bool $strict
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     *
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     * @return string
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     */
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    public static function getHash($var, bool $strict): string
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    {
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        return md5(static::getString($var, $strict));
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    }
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}
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