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:
Complex classes like Config often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Config, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 28 | class Config  | 
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| 29 | { | 
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| 30 | const PSR_0 = 'PSR-0';  | 
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| 31 | const PSR_4 = 'PSR-4';  | 
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| 32 | |||
| 33 | const COMMAND_CLASS = 'Symfony\Component\Console\Command\Command';  | 
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| 34 | |||
| 35 | /**  | 
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| 36 | * @var array config data  | 
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| 37 | */  | 
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| 38 | private $config = array();  | 
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| 39 | |||
| 40 | /**  | 
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| 41 | * @var array  | 
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| 42 | */  | 
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| 43 | private $partialConfig = array();  | 
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| 44 | |||
| 45 | /**  | 
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| 46 | * @var ConfigurationLoader  | 
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| 47 | */  | 
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| 48 | private $loader;  | 
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| 49 | |||
| 50 | /**  | 
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| 51 | * @var array  | 
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| 52 | */  | 
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| 53 | private $initConfig = array();  | 
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| 54 | |||
| 55 | /**  | 
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| 56 | * @var boolean  | 
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| 57 | */  | 
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| 58 | private $isPharMode;  | 
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| 59 | |||
| 60 | /**  | 
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| 61 | * @var OutputInterface  | 
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| 62 | */  | 
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| 63 | private $output;  | 
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| 64 | |||
| 65 | /**  | 
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| 66 | * Config constructor.  | 
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| 67 | *  | 
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| 68 | * @param array $initConfig  | 
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| 69 | * @param bool $isPharMode  | 
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| 70 | * @param OutputInterface $output [optional]  | 
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| 71 | */  | 
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| 72 | public function __construct(array $initConfig = array(), $isPharMode = false, OutputInterface $output = null)  | 
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| 78 | |||
| 79 | /**  | 
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| 80 | * alias magerun command in input from config  | 
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| 81 | *  | 
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| 82 | * @param InputInterface $input  | 
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| 83 | * @return ArgvInput|InputInterface  | 
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| 84 | */  | 
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| 85 | public function checkConfigCommandAlias(InputInterface $input)  | 
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| 115 | |||
| 116 | /**  | 
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| 117 | * @param Command $command  | 
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| 118 | */  | 
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| 119 | public function registerConfigCommandAlias(Command $command)  | 
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| 136 | |||
| 137 | /**  | 
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| 138 | * @param Application $application  | 
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| 139 | */  | 
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| 140 | public function registerCustomCommands(Application $application)  | 
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| 173 | |||
| 174 | /**  | 
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| 175 | * @param string $className  | 
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| 176 | * @param string|null $commandName  | 
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| 177 | * @return Command  | 
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| 178 | * @throws InvalidArgumentException  | 
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| 179 | */  | 
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| 180 | private function newCommand($className, $commandName)  | 
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| 206 | |||
| 207 | /**  | 
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| 208 | * Adds autoloader prefixes from user's config  | 
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| 209 | *  | 
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| 210 | * @param ClassLoader $autoloader  | 
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| 211 | */  | 
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| 212 | public function registerCustomAutoloaders(ClassLoader $autoloader)  | 
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| 228 | |||
| 229 | /**  | 
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| 230 | * @param array $config  | 
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| 231 | */  | 
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| 232 | public function setConfig(array $config)  | 
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| 236 | |||
| 237 | /**  | 
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| 238 | * @return array  | 
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| 239 | */  | 
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| 240 | public function getConfig()  | 
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| 244 | |||
| 245 | /**  | 
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| 246 | * @param ConfigurationLoader $configurationLoader  | 
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| 247 | */  | 
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| 248 | public function setLoader(ConfigurationLoader $configurationLoader)  | 
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| 252 | |||
| 253 | /**  | 
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| 254 | * @return ConfigurationLoader  | 
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| 255 | */  | 
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| 256 | public function getLoader()  | 
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| 265 | |||
| 266 | public function load()  | 
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| 270 | |||
| 271 | /**  | 
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| 272 | * @param bool $loadExternalConfig  | 
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| 273 | */  | 
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| 274 | public function loadPartialConfig($loadExternalConfig)  | 
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| 279 | |||
| 280 | /**  | 
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| 281 | * Get names of sub-folders to be scanned during Magento detection  | 
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| 282 | *  | 
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| 283 | * @return array  | 
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| 284 | */  | 
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| 285 | public function getDetectSubFolders()  | 
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| 293 | |||
| 294 | /**  | 
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| 295 | * @param array $initConfig  | 
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| 296 | * @param bool $isPharMode  | 
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| 297 | * @param OutputInterface $output  | 
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| 298 | *  | 
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| 299 | * @return ConfigurationLoader  | 
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| 300 | */  | 
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| 301 | public function createLoader(array $initConfig, $isPharMode, OutputInterface $output)  | 
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| 309 | |||
| 310 | /**  | 
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| 311 | * @param string $message  | 
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| 312 | */  | 
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| 313 | private function debugWriteln($message)  | 
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| 320 | |||
| 321 | /**  | 
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| 322 | * Get array from config, default to an empty array if not set  | 
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| 323 | *  | 
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| 324 | * @param string|array $key  | 
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| 325 | * @param array $default [optional]  | 
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| 326 | * @return array  | 
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| 327 | */  | 
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| 328 | private function getArray($key, $default = array())  | 
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| 337 | |||
| 338 | private function traverse(array $keys)  | 
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| 354 | }  | 
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| 355 | 
Instead of super-globals, we recommend to explicitly inject the dependencies of your class. This makes your code less dependent on global state and it becomes generally more testable: