Cake\Localized\Validation\JpValidation::katakana PHP Method

    public static function katakana($check, $allowSpace = true)
    {
        if ($allowSpace) {
            $pattern = '/^(\\xe3(\\x80\\x80|\\x82[\\xa1-\\xbf]|\\x83[\\x80-\\xb6]|\\x83\\xbc))*$/';
        } else {
            $pattern = '/^(\\xe3(\\x82[\\xa1-\\xbf]|\\x83[\\x80-\\xb6]|\\x83\\xbc))*$/';
        }
        return (bool) preg_match($pattern, $check);
    }

 /**
  * test the katakana method of JpValidation
  *
  * @return void
  */
 public function testKatakana()
 {
     $this->assertTrue(JpValidation::katakana('ァイ　ヴエオヶー'));
     $this->assertFalse(JpValidation::katakana('-'));
     $this->assertFalse(JpValidation::katakana('０'));
     $this->assertFalse(JpValidation::katakana('あ'));
     $this->assertFalse(JpValidation::katakana('亜'));
     $this->assertFalse(JpValidation::katakana('ァイ　ヴエオヶー', false));
 }