Complex classes like Plugin 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 Plugin, and based on these observations, apply Extract Interface, too.
1 | <?php |
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34 | class Plugin implements PluginInterface, EventSubscriberInterface |
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35 | { |
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36 | |||
37 | const KEY_MAX_DEPTH = 'phpcodesniffer-search-depth'; |
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38 | |||
39 | const MESSAGE_ERROR_WRONG_MAX_DEPTH = |
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40 | 'The value of "%s" (in the composer.json "extra".section) must be an integer larger then %d, %s given.'; |
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41 | const MESSAGE_NOT_INSTALLED = 'PHPCodeSniffer is not installed'; |
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42 | const MESSAGE_NOTHING_TO_INSTALL = 'Nothing to install or update'; |
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43 | const MESSAGE_RUNNING_INSTALLER = 'Running PHPCodeSniffer Composer Installer'; |
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44 | |||
45 | const PACKAGE_NAME = 'squizlabs/php_codesniffer'; |
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46 | const PACKAGE_TYPE = 'phpcodesniffer-standard'; |
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47 | |||
48 | const PHPCS_CONFIG_KEY = 'installed_paths'; |
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49 | |||
50 | /** |
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51 | * @var Composer |
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52 | */ |
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53 | private $composer; |
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54 | |||
55 | /** |
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56 | * @var string |
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57 | */ |
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58 | private $cwd; |
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59 | |||
60 | /** |
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61 | * @var Filesystem |
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62 | */ |
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63 | private $filesystem; |
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64 | |||
65 | /** |
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66 | * @var array |
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67 | */ |
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68 | private $installedPaths; |
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69 | |||
70 | /** |
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71 | * @var IOInterface |
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72 | */ |
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73 | private $io; |
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74 | |||
75 | /** |
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76 | * @var ProcessExecutor |
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77 | */ |
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78 | private $processExecutor; |
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79 | |||
80 | /** |
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81 | * Triggers the plugin's main functionality. |
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82 | * |
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83 | * Makes it possible to run the plugin as a custom command. |
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84 | * |
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85 | * @param Event $event |
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86 | * |
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87 | * @throws \InvalidArgumentException |
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88 | * @throws \RuntimeException |
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89 | * @throws LogicException |
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90 | * @throws ProcessFailedException |
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91 | * @throws RuntimeException |
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92 | */ |
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93 | public static function run(Event $event) |
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105 | |||
106 | /** |
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107 | * {@inheritDoc} |
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108 | * |
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109 | * @throws \RuntimeException |
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110 | * @throws LogicException |
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111 | * @throws ProcessFailedException |
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112 | * @throws RuntimeException |
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113 | */ |
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114 | public function activate(Composer $composer, IOInterface $io) |
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121 | |||
122 | /** |
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123 | * Prepares the plugin so it's main functionality can be run. |
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124 | * |
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125 | * @throws \RuntimeException |
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126 | * @throws LogicException |
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127 | * @throws ProcessFailedException |
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128 | * @throws RuntimeException |
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129 | */ |
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130 | private function init() |
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138 | |||
139 | /** |
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140 | * {@inheritDoc} |
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141 | */ |
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142 | public static function getSubscribedEvents() |
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153 | |||
154 | /** |
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155 | * Entry point for post install and post update events. |
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156 | * |
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157 | * @throws \InvalidArgumentException |
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158 | * @throws LogicException |
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159 | * @throws ProcessFailedException |
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160 | * @throws RuntimeException |
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161 | */ |
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162 | public function onDependenciesChangedEvent() |
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185 | |||
186 | /** |
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187 | * Load all paths from PHP_CodeSniffer into an array. |
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188 | * |
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189 | * @throws LogicException |
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190 | * @throws ProcessFailedException |
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191 | * @throws RuntimeException |
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192 | */ |
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193 | private function loadInstalledPaths() |
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213 | |||
214 | /** |
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215 | * Save all coding standard paths back into PHP_CodeSniffer |
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216 | * |
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217 | * @throws LogicException |
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218 | * @throws ProcessFailedException |
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219 | * @throws RuntimeException |
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220 | */ |
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221 | private function saveInstalledPaths() |
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256 | |||
257 | /** |
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258 | * Iterate trough all known paths and check if they are still valid. |
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259 | * |
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260 | * If path does not exists, is not an directory or isn't readable, the path |
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261 | * is removed from the list. |
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262 | * |
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263 | * @return bool True if changes where made, false otherwise |
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264 | */ |
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265 | private function cleanInstalledPaths() |
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281 | |||
282 | /** |
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283 | * Check all installed packages (including the root package) against |
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284 | * the installed paths from PHP_CodeSniffer and add the missing ones. |
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285 | * |
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286 | * @return bool True if changes where made, false otherwise |
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287 | * |
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288 | * @throws \InvalidArgumentException |
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289 | * @throws \RuntimeException |
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290 | */ |
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291 | private function updateInstalledPaths() |
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343 | |||
344 | /** |
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345 | * Iterates through Composers' local repository looking for valid Coding |
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346 | * Standard packages. |
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347 | * |
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348 | * If the package is the RootPackage (the one the plugin is installed into), |
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349 | * the package is ignored for now since it needs a different install path logic. |
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350 | * |
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351 | * @return array Composer packages containing coding standard(s) |
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352 | */ |
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353 | private function getPHPCodingStandardPackages() |
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373 | |||
374 | /** |
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375 | * Searches for the installed PHP_CodeSniffer Composer package |
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376 | * |
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377 | * @param null|string|\Composer\Semver\Constraint\ConstraintInterface $versionConstraint to match against |
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378 | * |
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379 | * @return PackageInterface|null |
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380 | */ |
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381 | private function getPHPCodeSnifferPackage($versionConstraint = null) |
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391 | |||
392 | /** |
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393 | * Returns the path to the PHP_CodeSniffer package installation location |
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394 | * |
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395 | * @return string |
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396 | */ |
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397 | private function getPHPCodeSnifferInstallPath() |
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401 | |||
402 | /** |
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403 | * Simple check if PHP_CodeSniffer is installed. |
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404 | * |
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405 | * @param null|string|\Composer\Semver\Constraint\ConstraintInterface $versionConstraint to match against |
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406 | * |
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407 | * @return bool Whether PHP_CodeSniffer is installed |
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408 | */ |
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409 | private function isPHPCodeSnifferInstalled($versionConstraint = null) |
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413 | |||
414 | /** |
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415 | * Test if composer is running "global" |
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416 | * This check kinda dirty, but it is the "Composer Way" |
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417 | * |
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418 | * @return bool Whether Composer is running "globally" |
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419 | * |
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420 | * @throws \RuntimeException |
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421 | */ |
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422 | private function isRunningGlobally() |
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426 | |||
427 | /** |
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428 | * Determines the maximum search depth when searching for Coding Standards. |
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429 | * |
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430 | * @return int |
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431 | * |
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432 | * @throws \InvalidArgumentException |
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433 | */ |
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434 | private function getMaxDepth() |
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463 | |||
464 | /** |
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465 | * Returns the minimal search depth for Coding Standard packages. |
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466 | * |
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467 | * Usually this is 0, unless PHP_CodeSniffer >= 3 is used. |
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468 | * |
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469 | * @return int |
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470 | */ |
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471 | private function getMinDepth() |
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478 | } |
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479 |
Unless you are absolutely sure that the expression can never be null because of other conditions, we strongly recommend to add an additional type check to your code: