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 RawDrupalContext 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 RawDrupalContext, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 29 | class RawDrupalContext extends RawMinkContext implements DrupalAwareInterface { | 
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| 30 | |||
| 31 | use DrupalParametersTrait;  | 
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| 32 | |||
| 33 | /**  | 
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| 34 | * Drupal driver manager.  | 
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| 35 | *  | 
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| 36 | * @var \Drupal\DrupalDriverManager  | 
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| 37 | */  | 
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| 38 | private $drupal;  | 
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| 39 | |||
| 40 | /**  | 
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| 41 | * Event dispatcher object.  | 
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| 42 | *  | 
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| 43 | * @var \Behat\Testwork\Hook\HookDispatcher  | 
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| 44 | */  | 
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| 45 | protected $dispatcher;  | 
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| 46 | |||
| 47 | /**  | 
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| 48 | * Drupal authentication manager.  | 
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| 49 | *  | 
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| 50 | * @var \Drupal\DrupalExtension\Manager\DrupalAuthenticationManagerInterface  | 
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| 51 | */  | 
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| 52 | protected $authenticationManager;  | 
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| 53 | |||
| 54 | /**  | 
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| 55 | * Drupal user manager.  | 
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| 56 | *  | 
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| 57 | * @var \Drupal\DrupalExtension\Manager\DrupalUserManagerInterface  | 
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| 58 | */  | 
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| 59 | protected $userManager;  | 
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| 60 | |||
| 61 | /**  | 
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| 62 | * Keep track of nodes so they can be cleaned up.  | 
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| 63 | *  | 
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| 64 | * @var array  | 
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| 65 | */  | 
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| 66 | protected $nodes = array();  | 
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| 67 | |||
| 68 | /**  | 
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| 69 | * Keep track of all terms that are created so they can easily be removed.  | 
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| 70 | *  | 
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| 71 | * @var array  | 
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| 72 | */  | 
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| 73 | protected $terms = array();  | 
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| 74 | |||
| 75 | /**  | 
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| 76 | * Keep track of any roles that are created so they can easily be removed.  | 
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| 77 | *  | 
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| 78 | * @var array  | 
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| 79 | */  | 
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| 80 | protected $roles = array();  | 
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| 81 | |||
| 82 | /**  | 
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| 83 | * Keep track of any languages that are created so they can easily be removed.  | 
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| 84 | *  | 
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| 85 | * @var array  | 
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| 86 | */  | 
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| 87 | protected $languages = array();  | 
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| 88 | |||
| 89 | /**  | 
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| 90 |    * {@inheritDoc} | 
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| 91 | */  | 
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| 92 |   public function setDrupal(DrupalDriverManager $drupal) { | 
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| 95 | |||
| 96 | /**  | 
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| 97 |    * {@inheritDoc} | 
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| 98 | */  | 
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| 99 |   public function getDrupal() { | 
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| 102 | |||
| 103 | /**  | 
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| 104 |    * {@inheritDoc} | 
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| 105 | */  | 
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| 106 |   public function setUserManager(DrupalUserManagerInterface $userManager) { | 
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| 109 | |||
| 110 | /**  | 
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| 111 |    * {@inheritdoc} | 
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| 112 | */  | 
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| 113 |   public function getUserManager() { | 
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| 116 | |||
| 117 | /**  | 
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| 118 |    * {@inheritdoc} | 
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| 119 | */  | 
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| 120 |   public function setAuthenticationManager(DrupalAuthenticationManagerInterface $authenticationManager) { | 
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| 123 | |||
| 124 | /**  | 
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| 125 |    * {@inheritdoc} | 
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| 126 | */  | 
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| 127 |   public function getAuthenticationManager() { | 
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| 130 | |||
| 131 | /**  | 
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| 132 | * Magic setter.  | 
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| 133 | */  | 
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| 134 |   public function __set($name, $value) { | 
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| 158 | |||
| 159 | /**  | 
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| 160 | * Magic getter.  | 
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| 161 | */  | 
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| 162 |   public function __get($name) { | 
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| 177 | |||
| 178 | /**  | 
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| 179 |    * {@inheritdoc} | 
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| 180 | */  | 
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| 181 |   public function setDispatcher(HookDispatcher $dispatcher) { | 
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| 184 | |||
| 185 | /**  | 
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| 186 | * Get active Drupal Driver.  | 
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| 187 | *  | 
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| 188 | * @return \Drupal\Driver\DrupalDriver  | 
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| 189 | */  | 
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| 190 |   public function getDriver($name = NULL) { | 
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| 193 | |||
| 194 | /**  | 
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| 195 | * Get driver's random generator.  | 
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| 196 | */  | 
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| 197 |   public function getRandom() { | 
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| 200 | |||
| 201 | /**  | 
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| 202 | * Massage node values to match the expectations on different Drupal versions.  | 
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| 203 | *  | 
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| 204 | * @beforeNodeCreate  | 
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| 205 | */  | 
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| 206 |   public static function alterNodeParameters(BeforeNodeCreateScope $scope) { | 
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| 228 | |||
| 229 | /**  | 
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| 230 | * Remove any created nodes.  | 
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| 231 | *  | 
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| 232 | * @AfterScenario  | 
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| 233 | */  | 
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| 234 |   public function cleanNodes() { | 
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| 241 | |||
| 242 | /**  | 
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| 243 | * Remove any created users.  | 
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| 244 | *  | 
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| 245 | * @AfterScenario  | 
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| 246 | */  | 
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| 247 |   public function cleanUsers() { | 
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| 260 | |||
| 261 | /**  | 
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| 262 | * Remove any created terms.  | 
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| 263 | *  | 
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| 264 | * @AfterScenario  | 
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| 265 | */  | 
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| 266 |   public function cleanTerms() { | 
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| 273 | |||
| 274 | /**  | 
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| 275 | * Remove any created roles.  | 
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| 276 | *  | 
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| 277 | * @AfterScenario  | 
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| 278 | */  | 
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| 279 |   public function cleanRoles() { | 
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| 286 | |||
| 287 | /**  | 
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| 288 | * Remove any created languages.  | 
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| 289 | *  | 
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| 290 | * @AfterScenario  | 
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| 291 | */  | 
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| 292 |   public function cleanLanguages() { | 
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| 299 | |||
| 300 | /**  | 
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| 301 | * Clear static caches.  | 
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| 302 | *  | 
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| 303 | * @AfterScenario @api  | 
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| 304 | */  | 
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| 305 |   public function clearStaticCaches() { | 
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| 308 | |||
| 309 | /**  | 
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| 310 | * Dispatch scope hooks.  | 
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| 311 | *  | 
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| 312 | * @param string $scope  | 
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| 313 | * The entity scope to dispatch.  | 
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| 314 | * @param \stdClass $entity  | 
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| 315 | * The entity.  | 
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| 316 | */  | 
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| 317 |   protected function dispatchHooks($scopeType, \stdClass $entity) { | 
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| 330 | |||
| 331 | /**  | 
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| 332 | * Create a node.  | 
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| 333 | *  | 
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| 334 | * @return object  | 
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| 335 | * The created node.  | 
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| 336 | */  | 
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| 337 | View Code Duplication |   public function nodeCreate($node) { | 
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| 345 | |||
| 346 | /**  | 
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| 347 | * Parses the field values and turns them into the format expected by Drupal.  | 
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| 348 | *  | 
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| 349 | * Multiple values in a single field must be separated by commas. Wrap the  | 
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| 350 | * field value in double quotes in case it should contain a comma.  | 
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| 351 | *  | 
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| 352 | * Compound field properties are identified using a ':' operator, either in  | 
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| 353 | * the column heading or in the cell. If multiple properties are present in a  | 
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| 354 | * single cell, they must be separated using ' - ', and values should not  | 
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| 355 | * contain ':' or ' - '.  | 
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| 356 | *  | 
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| 357 | * Possible formats for the values:  | 
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| 358 | * A  | 
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| 359 | * A, B, "a value, containing a comma"  | 
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| 360 | * A - B  | 
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| 361 | * x: A - y: B  | 
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| 362 | * A - B, C - D, "E - F"  | 
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| 363 | * x: A - y: B, x: C - y: D, "x: E - y: F"  | 
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| 364 | *  | 
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| 365 | * See field_handlers.feature for examples of usage.  | 
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| 366 | *  | 
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| 367 | * @param string $entity_type  | 
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| 368 | * The entity type.  | 
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| 369 | * @param \stdClass $entity  | 
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| 370 | * An object containing the entity properties and fields as properties.  | 
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| 371 | *  | 
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| 372 | * @throws \Exception  | 
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| 373 | * Thrown when a field name is invalid.  | 
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| 374 | */  | 
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| 375 |   public function parseEntityFields($entity_type, \stdClass $entity) { | 
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| 452 | |||
| 453 | /**  | 
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| 454 | * Create a user.  | 
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| 455 | *  | 
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| 456 | * @return object  | 
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| 457 | * The created user.  | 
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| 458 | */  | 
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| 459 |   public function userCreate($user) { | 
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| 467 | |||
| 468 | /**  | 
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| 469 | * Create a term.  | 
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| 470 | *  | 
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| 471 | * @return object  | 
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| 472 | * The created term.  | 
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| 473 | */  | 
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| 474 | View Code Duplication |   public function termCreate($term) { | 
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| 482 | |||
| 483 | /**  | 
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| 484 | * Creates a language.  | 
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| 485 | *  | 
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| 486 | * @param \stdClass $language  | 
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| 487 | * An object with the following properties:  | 
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| 488 | * - langcode: the langcode of the language to create.  | 
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| 489 | *  | 
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| 490 | * @return object|FALSE  | 
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| 491 | * The created language, or FALSE if the language was already created.  | 
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| 492 | */  | 
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| 493 |   public function languageCreate(\stdClass $language) { | 
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| 502 | |||
| 503 | /**  | 
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| 504 | * Log-in the given user.  | 
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| 505 | *  | 
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| 506 | * @param \stdClass $user  | 
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| 507 | * The user to log in.  | 
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| 508 | */  | 
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| 509 |   public function login(\stdClass $user) { | 
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| 512 | |||
| 513 | /**  | 
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| 514 | * Logs the current user out.  | 
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| 515 | */  | 
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| 516 |   public function logout() { | 
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| 519 | |||
| 520 | /**  | 
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| 521 | * Determine if the a user is already logged in.  | 
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| 522 | *  | 
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| 523 | * @return boolean  | 
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| 524 | * Returns TRUE if a user is logged in for this session.  | 
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| 525 | */  | 
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| 526 |   public function loggedIn() { | 
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| 529 | |||
| 530 | /**  | 
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| 531 | * User with a given role is already logged in.  | 
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| 532 | *  | 
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| 533 | * @param string $role  | 
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| 534 | * A single role, or multiple comma-separated roles in a single string.  | 
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| 535 | *  | 
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| 536 | * @return boolean  | 
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| 537 | * Returns TRUE if the current logged in user has this role (or roles).  | 
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| 538 | */  | 
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| 539 |   public function loggedInWithRole($role) { | 
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| 542 | |||
| 543 | /**  | 
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| 544 | * Returns the Behat context that corresponds with the given class name.  | 
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| 545 | *  | 
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| 546 | * This is inspired by InitializedContextEnvironment::getContext() but also  | 
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| 547 | * returns subclasses of the given class name. This allows us to retrieve for  | 
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| 548 | * example DrupalContext even if it is overridden in a project.  | 
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| 549 | *  | 
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| 550 | * @param string $class  | 
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| 551 | * A fully namespaced class name.  | 
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| 552 | *  | 
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| 553 | * @return \Behat\Behat\Context\Context|false  | 
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| 554 | * The requested context, or FALSE if the context is not registered.  | 
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| 555 | *  | 
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| 556 | * @throws \Exception  | 
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| 557 | * Thrown when the environment is not yet initialized, meaning that contexts  | 
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| 558 | * cannot yet be retrieved.  | 
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| 559 | */  | 
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| 560 |   protected function getContext($class) { | 
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| 579 | |||
| 580 | }  | 
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| 581 | 
Let’s take a look at an example:
In the above example, the authenticate() method works fine as long as you just pass instances of MyUser. However, if you now also want to pass a different implementation of User which does not have a getDisplayName() method, the code will break.
Available Fixes
Change the type-hint for the parameter:
Add an additional type-check:
Add the method to the interface: