class-inflect.php

<?php
/**
 * Static Inflector class
 *
 * Author: T. Brian Jones
 * Author URI: https://github.com/tbrianjones
 *
 * @author @tbrianjones
 * @link https://gist.github.com/tbrianjones/ba0460cc1d55f357e00b
 * @package WPGraphQL\Extensions\WooCommerce
 * @since 0.0.4
 */

/**
 * Class Inflect
 */
class Inflect {
	/**
	 * Stores plural suffixes.
	 *
	 * @var array $plural
	 */
	private static $plural = array(
		'/(quiz)$/i'                     => '$1zes',
		'/^(ox)$/i'                      => '$1en',
		'/([m|l])ouse$/i'                => '$1ice',
		'/(matr|vert|ind)ix|ex$/i'       => '$1ices',
		'/(x|ch|ss|sh)$/i'               => '$1es',
		'/([^aeiouy]|qu)y$/i'            => '$1ies',
		'/(hive)$/i'                     => '$1s',
		'/(?:([^f])fe|([lr])f)$/i'       => '$1$2ves',
		'/(shea|lea|loa|thie)f$/i'       => '$1ves',
		'/sis$/i'                        => 'ses',
		'/([ti])um$/i'                   => '$1a',
		'/(tomat|potat|ech|her|vet)o$/i' => '$1oes',
		'/(bu)s$/i'                      => '$1ses',
		'/(alias)$/i'                    => '$1es',
		'/(octop)us$/i'                  => '$1i',
		'/(ax|test)is$/i'                => '$1es',
		'/(us)$/i'                       => '$1es',
		'/s$/i'                          => 's',
		'/$/'                            => 's',
	);

	/**
	 * Stores singular suffixes
	 *
	 * @var array $singular
	 */
	private static $singular = array(
		'/(quiz)zes$/i'              => '$1',
		'/(matr)ices$/i'             => '$1ix',
		'/(vert|ind)ices$/i'         => '$1ex',
		'/^(ox)en$/i'                => '$1',
		'/(alias)es$/i'              => '$1',
		'/(octop|vir)i$/i'           => '$1us',
		'/(cris|ax|test)es$/i'       => '$1is',
		'/(shoe)s$/i'                => '$1',
		'/(o)es$/i'                  => '$1',
		'/(bus)es$/i'                => '$1',
		'/([m|l])ice$/i'             => '$1ouse',
		'/(x|ch|ss|sh)es$/i'         => '$1',
		'/(m)ovies$/i'               => '$1ovie',
		'/(s)eries$/i'               => '$1eries',
		'/([^aeiouy]|qu)ies$/i'      => '$1y',
		'/([lr])ves$/i'              => '$1f',
		'/(tive)s$/i'                => '$1',
		'/(hive)s$/i'                => '$1',
		'/(li|wi|kni)ves$/i'         => '$1fe',
		'/(shea|loa|lea|thie)ves$/i' => '$1f',
		'/(^analy)ses$/i'            => '$1sis',
		'/((a)naly|(b)a|(d)iagno|(p)arenthe|(p)rogno|(s)ynop|(t)he)ses$/i' => '$1$2sis',
		'/([ti])a$/i'                => '$1um',
		'/(n)ews$/i'                 => '$1ews',
		'/(h|bl)ouses$/i'            => '$1ouse',
		'/(corpse)s$/i'              => '$1',
		'/(us)es$/i'                 => '$1',
		'/s$/i'                      => '',
	);

	/**
	 * Stores irregular words
	 *
	 * @var array $irregular
	 */
	private static $irregular = array(
		'move'   => 'moves',
		'foot'   => 'feet',
		'goose'  => 'geese',
		'sex'    => 'sexes',
		'child'  => 'children',
		'man'    => 'men',
		'tooth'  => 'teeth',
		'person' => 'people',
		'valve'  => 'valves',
	);

	/**
	 * Stores words without plural tenses
	 *
	 * @var array $uncountable
	 */
	private static $uncountable = array(
		'sheep',
		'fish',
		'deer',
		'series',
		'species',
		'money',
		'rice',
		'information',
		'equipment',
	);

	/**
	 * Return plural tense of provide string
	 *
	 * @param string $string - word to be pluralized.
	 * @return string
	 */
	public static function pluralize( $string ) {
		// save some time in the case that singular and plural are the same.
		if ( in_array( strtolower( $string ), self::$uncountable, true ) ) {
			return $string;
		}

		// check for irregular singular forms.
		foreach ( self::$irregular as $pattern => $result ) {
			$pattern = '/' . $pattern . '$/i';

			if ( preg_match( $pattern, $string ) ) {
				return preg_replace( $pattern, $result, $string );
			}
		}

		// check for matches using regular expressions.
		foreach ( self::$plural as $pattern => $result ) {
			if ( preg_match( $pattern, $string ) ) {
				return preg_replace( $pattern, $result, $string );
			}
		}

		return $string;
	}

	/**
	 * Return singular tense of provided string
	 *
	 * @param string $string String to be singularized.
	 * @return string
	 */
	public static function singularize( $string ) {
		// save some time in the case that singular and plural are the same.
		if ( in_array( strtolower( $string ), self::$uncountable, true ) ) {
			return $string;
		}

		// check for irregular plural forms.
		foreach ( self::$irregular as $result => $pattern ) {
			$pattern = '/' . $pattern . '$/i';

			if ( preg_match( $pattern, $string ) ) {
				return preg_replace( $pattern, $result, $string );
			}
		}

		// check for matches using regular expressions.
		foreach ( self::$singular as $pattern => $result ) {
			if ( preg_match( $pattern, $string ) ) {
				return preg_replace( $pattern, $result, $string );
			}
		}

		return $string;
	}

	/**
	 * Return plural tense if provided count is greater than 1
	 *
	 * @param int    $count Count to be evaluated.
	 * @param string $string String potentially pluralized.
	 */
	public static function pluralize_if( $count, $string ) {
		if ( 1 === $count ) {
			return '1 $string';
		}

		return $count . ' ' . self::pluralize( $string );
	}
}