Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
| 1 | <?php  | 
            ||
| 9 | class MonologHandlerFactory  | 
            ||
| 10 | { | 
            ||
| 11 | /**  | 
            ||
| 12 | * Returns an instance of \Monolog\Handler\HandlerInterface  | 
            ||
| 13 | * @param string $name Then name of the handler you want to create  | 
            ||
| 14 | * @param array $config An array of config values to use  | 
            ||
| 15 | * @param string $title  | 
            ||
| 16 | * @return \Monolog\Handler\HandlerInterface  | 
            ||
| 17 | */  | 
            ||
| 18 | 33 |     public static function create($name, array $config = [], $title = null){ | 
            |
| 21 | |||
| 22 | /**  | 
            ||
| 23 | * Returns a PushoverHandler  | 
            ||
| 24 | * @param array $config An array of config values to use  | 
            ||
| 25 | * @param string $title The title/subject to use  | 
            ||
| 26 | * @return \Monolog\Handler\PushoverHandler  | 
            ||
| 27 | */  | 
            ||
| 28 | 9 |     protected static function pushover(array $config = [], $title = null){ | 
            |
| 56 | |||
| 57 | /**  | 
            ||
| 58 | * Returns a FlowdockHandler  | 
            ||
| 59 | * @param array $config An array of config values to use  | 
            ||
| 60 | * @param string $title The title/subject to use  | 
            ||
| 61 | * @return \Monolog\Handler\FlowdockHandler  | 
            ||
| 62 | */  | 
            ||
| 63 | 3 | View Code Duplication |     protected static function flowdock(array $config = [], $title = null){ | 
            
| 76 | |||
| 77 | /**  | 
            ||
| 78 | * Returns a FleepHookHandler  | 
            ||
| 79 | * @param array $config An array of config values to use  | 
            ||
| 80 | * @param string $title The title/subject to use  | 
            ||
| 81 | * @return \Monolog\Handler\FleepHookHandler  | 
            ||
| 82 | */  | 
            ||
| 83 | 3 | View Code Duplication |     protected static function fleephook(array $config = [], $title = null){ | 
            
| 96 | |||
| 97 | /**  | 
            ||
| 98 | * Returns a PlivoHandler  | 
            ||
| 99 | * @param array $config An array of config values to use  | 
            ||
| 100 | * @param string $title The title/subject to use  | 
            ||
| 101 | * @return \Tylercd100\Monolog\Handler\PlivoHandler  | 
            ||
| 102 | */  | 
            ||
| 103 | 3 | View Code Duplication |     protected static function plivo(array $config = [], $title = null){ | 
            
| 125 | |||
| 126 | /**  | 
            ||
| 127 | * Returns a TwilioHandler  | 
            ||
| 128 | * @param array $config An array of config values to use  | 
            ||
| 129 | * @param string $title The title/subject to use  | 
            ||
| 130 | * @return \Tylercd100\Monolog\Handler\TwilioHandler  | 
            ||
| 131 | */  | 
            ||
| 132 | 3 | View Code Duplication |     protected static function twilio(array $config = [], $title = null){ | 
            
| 154 | |||
| 155 | /**  | 
            ||
| 156 | * Returns a SlackHandler  | 
            ||
| 157 | * @param array $config An array of config values to use  | 
            ||
| 158 | * @param string $title The title/subject to use  | 
            ||
| 159 | * @return \Monolog\Handler\SlackHandler  | 
            ||
| 160 | */  | 
            ||
| 161 | 9 |     protected static function slack(array $config = [], $title = null){ | 
            |
| 185 | |||
| 186 | /**  | 
            ||
| 187 | * Returns a HipChatHandler  | 
            ||
| 188 | * @param array $config An array of config values to use  | 
            ||
| 189 | * @param string $title The title/subject to use  | 
            ||
| 190 | * @return \Monolog\Handler\HipChatHandler  | 
            ||
| 191 | */  | 
            ||
| 192 | 9 |     protected static function hipchat(array $config = [], $title = null){ | 
            |
| 218 | |||
| 219 | /**  | 
            ||
| 220 | * Creates Mail Monolog Handler  | 
            ||
| 221 | * @param array $config An array of config values to use  | 
            ||
| 222 | * @param string $title The title/subject to use  | 
            ||
| 223 | * @return \Monolog\Handler\MailHandler  | 
            ||
| 224 | */  | 
            ||
| 225 | 6 | protected static function mail(array $config = [], $title = null)  | 
            |
| 233 | |||
| 234 | /**  | 
            ||
| 235 | * Creates Mail Monolog Handler  | 
            ||
| 236 | * @param array $config An array of config values to use  | 
            ||
| 237 | * @param string $title The title/subject to use  | 
            ||
| 238 | * @return \Monolog\Handler\SwiftMailerHandler  | 
            ||
| 239 | */  | 
            ||
| 240 | 3 | protected static function swiftMail(array $config, $title = null)  | 
            |
| 258 | |||
| 259 | /**  | 
            ||
| 260 | * Creates Mail Monolog Handler  | 
            ||
| 261 | * @param array $config An array of config values to use  | 
            ||
| 262 | * @param string $title The title/subject to use  | 
            ||
| 263 | * @return \Monolog\Handler\NativeMailerHandler  | 
            ||
| 264 | */  | 
            ||
| 265 | 3 | protected static function nativeMail(array $config, $title = null)  | 
            |
| 286 | }  | 
            
This check looks from parameters that have been defined for a function or method, but which are not used in the method body.