<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\PropertyAccess;
/**
* Creates singulars from plurals.
*
* @author Bernhard Schussek <bschussek@gmail.com>
*/
class StringUtil
{
/**
* Map english plural to singular suffixes
*
* @var array
*
* @see http://english-zone.com/spelling/plurals.html
* @see http://www.scribd.com/doc/3271143/List-of-100-Irregular-Plural-Nouns-in-English
*/
private static $pluralMap = array(
// First entry: plural suffix, reversed
// Second entry: length of plural suffix
// Third entry: Whether the suffix may succeed a vocal
// Fourth entry: Whether the suffix may succeed a consonant
// Fifth entry: singular suffix, normal
// bacteria (bacterium), criteria (criterion), phenomena (phenomenon)
array('a', 1, true, true, array('on', 'um')),
// nebulae (nebula)
array('ea', 2, true, true, 'a'),
// mice (mouse), lice (louse)
array('eci', 3, false, true, 'ouse'),
// geese (goose)
array('esee', 4, false, true, 'oose'),
// fungi (fungus), alumni (alumnus), syllabi (syllabus), radii (radius)
array('i', 1, true, true, 'us'),
// men (man), women (woman)
array('nem', 3, true, true, 'man'),
// children (child)
array('nerdlihc', 8, true, true, 'child'),
// oxen (ox)
array('nexo', 4, false, false, 'ox'),
// indices (index), appendices (appendix), prices (price)
array('seci', 4, false, true, array('ex', 'ix', 'ice')),
// babies (baby)
array('sei', 3, false, true, 'y'),
// analyses (analysis), ellipses (ellipsis), funguses (fungus),
// neuroses (neurosis), theses (thesis), emphases (emphasis),
// oases (oasis), crises (crisis), houses (house), bases (base),
// atlases (atlas), kisses (kiss)
array('ses', 3, true, true, array('s', 'se', 'sis')),
// objectives (objective), alternative (alternatives)
array('sevit', 5, true, true, 'tive'),
// lives (life), wives (wife)
array('sevi', 4, false, true, 'ife'),
// hooves (hoof), dwarves (dwarf), elves (elf), leaves (leaf)
array('sev', 3, true, true, 'f'),
// axes (axis), axes (ax), axes (axe)
array('sexa', 4, false, false, array('ax', 'axe', 'axis')),
// indexes (index), matrixes (matrix)
array('sex', 3, true, false, 'x'),
// quizzes (quiz)
array('sezz', 4, true, false, 'z'),
// bureaus (bureau)
array('suae', 4, false, true, 'eau'),
// roses (rose), garages (garage), cassettes (cassette),
// waltzes (waltz), heroes (hero), bushes (bush), arches (arch),
// shoes (shoe)
array('se', 2, true, true, array('', 'e')),
// tags (tag)
array('s', 1, true, true, ''),
// chateaux (chateau)
array('xuae', 4, false, true, 'eau'),
);
/**
* This class should not be instantiated
*/
private function __construct() {}
/**
* Returns the singular form of a word
*
* If the method can't determine the form with certainty, an array of the
* possible singulars is returned.
*
* @param string $plural A word in plural form
* @return string|array The singular form or an array of possible singular
* forms
*/
public static function singularify($plural)
{
$pluralRev = strrev($plural);
$lowerPluralRev = strtolower($pluralRev);
$pluralLength = strlen($lowerPluralRev);
// The outer loop iterates over the entries of the plural table
// The inner loop $j iterates over the characters of the plural suffix
// in the plural table to compare them with the characters of the actual
// given plural suffix
foreach (self::$pluralMap as $map) {
$suffix = $map[0];
$suffixLength = $map[1];
$j = 0;
// Compare characters in the plural table and of the suffix of the
// given plural one by one
while ($suffix[$j] === $lowerPluralRev[$j]) {
// Let $j point to the next character
++$j;
// Successfully compared the last character
// Add an entry with the singular suffix to the singular array
if ($j === $suffixLength) {
// Is there any character preceding the suffix in the plural string?
if ($j < $pluralLength) {
$nextIsVocal = false !== strpos('aeiou', $lowerPluralRev[$j]);
if (!$map[2] && $nextIsVocal) {
// suffix may not succeed a vocal but next char is one
break;
}
if (!$map[3] && !$nextIsVocal) {
// suffix may not succeed a consonant but next char is one
break;
}
}
$newBase = substr($plural, 0, $pluralLength - $suffixLength);
$newSuffix = $map[4];
// Check whether the first character in the plural suffix
// is uppercased. If yes, uppercase the first character in
// the singular suffix too
$firstUpper = ctype_upper($pluralRev[$j - 1]);
if (is_array($newSuffix)) {
$singulars = array();
foreach ($newSuffix as $newSuffixEntry) {
$singulars[] = $newBase.($firstUpper ? ucfirst($newSuffixEntry) : $newSuffixEntry);
}
return $singulars;
}
return $newBase.($firstUpper ? ucFirst($newSuffix) : $newSuffix);
}
// Suffix is longer than word
if ($j === $pluralLength) {
break;
}
}
}
// Convert teeth to tooth, feet to foot
if (false !== ($pos = strpos($plural, 'ee'))) {
return substr_replace($plural, 'oo', $pos, 2);
}
// Assume that plural and singular is identical
return $plural;
}
}
