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 SchemaPluginBase 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 SchemaPluginBase, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 26 | abstract class SchemaPluginBase extends PluginBase implements SchemaPluginInterface, SchemaBuilderInterface, ContainerFactoryPluginInterface, CacheableDependencyInterface { |
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| 27 | |||
| 28 | /** |
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| 29 | * The field plugin manager. |
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| 30 | * |
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| 31 | * @var \Drupal\graphql\Plugin\FieldPluginManager |
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| 32 | */ |
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| 33 | protected $fieldManager; |
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| 34 | |||
| 35 | /** |
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| 36 | * The mutation plugin manager. |
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| 37 | * |
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| 38 | * @var \Drupal\graphql\Plugin\MutationPluginManager |
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| 39 | */ |
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| 40 | protected $mutationManager; |
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| 41 | |||
| 42 | /** |
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| 43 | * The subscription plugin manager. |
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| 44 | * |
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| 45 | * @var \Drupal\graphql\Plugin\SubscriptionPluginManager |
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| 46 | */ |
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| 47 | protected $subscriptionManager; |
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| 48 | |||
| 49 | /** |
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| 50 | * The type manager aggregator service. |
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| 51 | * |
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| 52 | * @var \Drupal\graphql\Plugin\TypePluginManagerAggregator |
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| 53 | */ |
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| 54 | protected $typeManagers; |
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| 55 | |||
| 56 | /** |
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| 57 | * Static cache of field definitions. |
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| 58 | * |
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| 59 | * @var array |
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| 60 | */ |
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| 61 | protected $fields = []; |
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| 62 | |||
| 63 | /** |
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| 64 | * Static cache of mutation definitions. |
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| 65 | * |
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| 66 | * @var array |
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| 67 | */ |
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| 68 | protected $mutations = []; |
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| 69 | |||
| 70 | /** |
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| 71 | * Static cache of subscription definitions. |
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| 72 | * |
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| 73 | * @var array |
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| 74 | */ |
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| 75 | protected $subscriptions = []; |
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| 76 | |||
| 77 | /** |
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| 78 | * Static cache of type instances. |
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| 79 | * |
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| 80 | * @var array |
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| 81 | */ |
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| 82 | protected $types = []; |
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| 83 | |||
| 84 | /** |
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| 85 | * The service parameters |
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| 86 | * |
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| 87 | * @var array |
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| 88 | */ |
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| 89 | protected $parameters; |
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| 90 | |||
| 91 | /** |
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| 92 | * The query provider service. |
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| 93 | * |
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| 94 | * @var \Drupal\graphql\GraphQL\QueryProvider\QueryProviderInterface |
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| 95 | */ |
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| 96 | protected $queryProvider; |
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| 97 | |||
| 98 | /** |
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| 99 | * The current user. |
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| 100 | * |
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| 101 | * @var \Drupal\Core\Session\AccountProxyInterface |
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| 102 | */ |
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| 103 | protected $currentUser; |
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| 104 | |||
| 105 | /** |
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| 106 | * {@inheritdoc} |
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| 107 | */ |
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| 108 | public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) { |
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| 122 | |||
| 123 | /** |
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| 124 | * SchemaPluginBase constructor. |
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| 125 | * |
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| 126 | * @param array $configuration |
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| 127 | * The plugin configuration array. |
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| 128 | * @param string $pluginId |
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| 129 | * The plugin id. |
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| 130 | * @param array $pluginDefinition |
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| 131 | * The plugin definition array. |
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| 132 | * @param \Drupal\graphql\Plugin\FieldPluginManager $fieldManager |
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| 133 | * The field plugin manager. |
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| 134 | * @param \Drupal\graphql\Plugin\MutationPluginManager $mutationManager |
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| 135 | * The mutation plugin manager. |
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| 136 | * @param \Drupal\graphql\Plugin\SubscriptionPluginManager $subscriptionManager |
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| 137 | * The subscription plugin manager. |
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| 138 | * @param \Drupal\graphql\Plugin\TypePluginManagerAggregator $typeManagers |
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| 139 | * The type manager aggregator service. |
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| 140 | * @param \Drupal\graphql\GraphQL\QueryProvider\QueryProviderInterface $queryProvider |
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| 141 | * The query provider service. |
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| 142 | * @param \Drupal\Core\Session\AccountProxyInterface $currentUser |
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| 143 | * The current user. |
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| 144 | * @param array $parameters |
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| 145 | */ |
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| 146 | public function __construct( |
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| 167 | |||
| 168 | /** |
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| 169 | * {@inheritdoc} |
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| 170 | */ |
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| 171 | public function allowsQueryBatching() { |
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| 174 | |||
| 175 | /** |
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| 176 | * {@inheritdoc} |
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| 177 | */ |
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| 178 | public function inDebug() { |
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| 181 | |||
| 182 | /** |
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| 183 | * {@inheritdoc} |
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| 184 | */ |
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| 185 | public function getSchema() { |
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| 223 | |||
| 224 | /** |
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| 225 | * {@inheritdoc} |
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| 226 | */ |
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| 227 | public function getRootValue() { |
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| 230 | |||
| 231 | /** |
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| 232 | * {@inheritdoc} |
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| 233 | */ |
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| 234 | public function getContext() { |
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| 255 | |||
| 256 | /** |
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| 257 | * {@inheritdoc} |
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| 258 | */ |
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| 259 | public function getFieldResolver() { |
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| 262 | |||
| 263 | |||
| 264 | /** |
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| 265 | * {@inheritdoc} |
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| 266 | */ |
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| 267 | public function getValidationRules() { |
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| 279 | |||
| 280 | /** |
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| 281 | * {@inheritdoc} |
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| 282 | */ |
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| 283 | public function getPersistedQueryLoader() { |
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| 286 | |||
| 287 | /** |
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| 288 | * {@inheritdoc} |
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| 289 | */ |
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| 290 | public function hasFields($type) { |
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| 293 | |||
| 294 | /** |
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| 295 | * {@inheritdoc} |
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| 296 | */ |
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| 297 | public function hasMutations() { |
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| 300 | |||
| 301 | /** |
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| 302 | * {@inheritdoc} |
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| 303 | */ |
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| 304 | public function hasSubscriptions() { |
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| 307 | |||
| 308 | /** |
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| 309 | * {@inheritdoc} |
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| 310 | */ |
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| 311 | public function hasType($name) { |
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| 314 | |||
| 315 | /** |
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| 316 | * {@inheritdoc} |
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| 317 | */ |
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| 318 | public function getFields($type) { |
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| 330 | |||
| 331 | /** |
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| 332 | * {@inheritdoc} |
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| 333 | */ |
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| 334 | public function getMutations() { |
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| 337 | |||
| 338 | /** |
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| 339 | * {@inheritdoc} |
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| 340 | */ |
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| 341 | public function getSubscriptions() { |
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| 344 | |||
| 345 | /** |
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| 346 | * {@inheritdoc} |
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| 347 | */ |
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| 348 | public function getTypes() { |
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| 353 | |||
| 354 | /** |
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| 355 | * {@inheritdoc} |
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| 356 | */ |
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| 357 | public function getSubTypes($name) { |
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| 361 | |||
| 362 | /** |
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| 363 | * {@inheritdoc} |
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| 364 | */ |
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| 365 | public function resolveType($name, $value, ResolveContext $context, ResolveInfo $info) { |
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| 383 | |||
| 384 | /** |
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| 385 | * {@inheritdoc} |
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| 386 | */ |
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| 387 | public function getType($name) { |
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| 402 | |||
| 403 | /** |
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| 404 | * {@inheritdoc} |
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| 405 | */ |
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| 406 | public function processMutations($mutations) { |
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| 409 | |||
| 410 | /** |
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| 411 | * {@inheritdoc} |
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| 412 | */ |
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| 413 | public function processSubscriptions($subscriptions) { |
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| 416 | |||
| 417 | /** |
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| 418 | * {@inheritdoc} |
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| 419 | */ |
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| 420 | public function processFields($fields) { |
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| 423 | |||
| 424 | /** |
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| 425 | * {@inheritdoc} |
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| 426 | */ |
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| 427 | public function processArguments($args) { |
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| 434 | |||
| 435 | /** |
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| 436 | * {@inheritdoc} |
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| 437 | */ |
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| 438 | public function processType($type) { |
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| 445 | |||
| 446 | /** |
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| 447 | * Retrieves the type instance for the given reference. |
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| 448 | * |
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| 449 | * @param array $type |
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| 450 | * The type reference. |
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| 451 | * |
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| 452 | * @return \GraphQL\Type\Definition\Type |
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| 453 | * The type instance. |
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| 454 | */ |
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| 455 | protected function buildType($type) { |
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| 464 | |||
| 465 | /** |
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| 466 | * Retrieves the field definition for a given field reference. |
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| 467 | * |
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| 468 | * @param array $field |
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| 469 | * The type reference. |
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| 470 | * |
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| 471 | * @return array |
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| 472 | * The field definition. |
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| 473 | */ |
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| 474 | View Code Duplication | protected function buildField($field) { |
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| 482 | |||
| 483 | /** |
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| 484 | * Retrieves the mutation definition for a given field reference. |
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| 485 | * |
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| 486 | * @param array $mutation |
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| 487 | * The mutation reference. |
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| 488 | * |
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| 489 | * @return array |
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| 490 | * The mutation definition. |
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| 491 | */ |
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| 492 | View Code Duplication | protected function buildMutation($mutation) { |
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| 500 | |||
| 501 | /** |
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| 502 | * Retrieves the subscription definition for a given field reference. |
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| 503 | * |
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| 504 | * @param array $mutation |
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| 505 | * The subscription reference. |
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| 506 | * |
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| 507 | * @return array |
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| 508 | * The subscription definition. |
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| 509 | */ |
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| 510 | View Code Duplication | protected function buildSubscription($subscription) { |
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| 518 | |||
| 519 | /** |
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| 520 | * {@inheritdoc} |
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| 521 | */ |
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| 522 | public function getCacheContexts() { |
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| 525 | |||
| 526 | /** |
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| 527 | * {@inheritdoc} |
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| 528 | */ |
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| 529 | public function getCacheTags() { |
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| 532 | |||
| 533 | /** |
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| 534 | * {@inheritdoc} |
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| 535 | */ |
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| 536 | public function getCacheMaxAge() { |
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| 539 | } |
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| 540 |
Adding an explicit array definition is generally preferable to implicit array definition as it guarantees a stable state of the code.
Let’s take a look at an example:
As you can see in this example, the array
$myArrayis initialized the first time when the foreach loop is entered. You can also see that the value of thebarkey is only written conditionally; thus, its value might result from a previous iteration.This might or might not be intended. To make your intention clear, your code more readible and to avoid accidental bugs, we recommend to add an explicit initialization $myArray = array() either outside or inside the foreach loop.