Adding additional plural inflection rule.

cake/libs/inflector.php

@@ -124,7 +124,7 @@ class Inflector extends Object {
 			'/(alumn|bacill|cact|foc|fung|nucle|radi|stimul|syllab|termin|viri?)i$/i' => '\1us',
 			'/([ftw]ax)es/' => '\1',
 			'/(cris|ax|test)es$/i' => '\1is',
-			'/(shoe)s$/i' => '\1',
+			'/(shoe|slave)s$/i' => '\1',
 			'/(o)es$/i' => '\1',
 			'/ouses$/' => 'ouse',
 			'/uses$/' => 'us',

cake/tests/cases/libs/inflector.test.php

@@ -99,6 +99,7 @@ class InflectorTest extends CakeTestCase {
 		$this->assertEqual(Inflector::singularize('lives'), 'life');
 		$this->assertEqual(Inflector::singularize('knives'), 'knife');
 		$this->assertEqual(Inflector::singularize('wolves'), 'wolf');
+		$this->assertEqual(Inflector::singularize('slaves'), 'slave');
 		$this->assertEqual(Inflector::singularize('shelves'), 'shelf');
 		$this->assertEqual(Inflector::singularize('taxis'), 'taxi');
 		$this->assertEqual(Inflector::singularize('taxes'), 'tax');