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 FixtureContext 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 FixtureContext, and based on these observations, apply Extract Interface, too.
| 1 | <?php | ||
| 21 | class FixtureContext extends BehatContext | ||
| 22 | { | ||
| 23 | protected $context; | ||
| 24 | |||
| 25 | /** | ||
| 26 | * @var \FixtureFactory | ||
| 27 | */ | ||
| 28 | protected $fixtureFactory; | ||
| 29 | |||
| 30 | /** | ||
| 31 | * @var String Absolute path where file fixtures are located. | ||
| 32 | * These will automatically get copied to their location | ||
| 33 | * declare through the 'Given a file "..."' step defition. | ||
| 34 | */ | ||
| 35 | protected $filesPath; | ||
| 36 | |||
| 37 | /** | ||
| 38 | * @var String Tracks all files and folders created from fixtures, for later cleanup. | ||
| 39 | */ | ||
| 40 | protected $createdFilesPaths = array(); | ||
| 41 | |||
| 42 | /** | ||
| 43 | * @var array Stores the asset tuples. | ||
| 44 | */ | ||
| 45 | protected $createdAssets = array(); | ||
| 46 | |||
| 47 | public function __construct(array $parameters) | ||
| 51 | |||
| 52 | public function getSession($name = null) | ||
| 56 | |||
| 57 | /** | ||
| 58 | * @return \FixtureFactory | ||
| 59 | */ | ||
| 60 | public function getFixtureFactory() | ||
| 67 | |||
| 68 | /** | ||
| 69 | * @param \FixtureFactory $factory | ||
| 70 | */ | ||
| 71 | public function setFixtureFactory(\FixtureFactory $factory) | ||
| 75 | |||
| 76 | /** | ||
| 77 | * @param String | ||
| 78 | */ | ||
| 79 | public function setFilesPath($path) | ||
| 83 | |||
| 84 | /** | ||
| 85 | * @return String | ||
| 86 | */ | ||
| 87 | public function getFilesPath() | ||
| 91 | |||
| 92 | /** | ||
| 93 | * @BeforeScenario @database-defaults | ||
| 94 | */ | ||
| 95 | public function beforeDatabaseDefaults(ScenarioEvent $event) | ||
| 105 | |||
| 106 | /** | ||
| 107 | * @AfterScenario | ||
| 108 | */ | ||
| 109 | public function afterResetDatabase(ScenarioEvent $event) | ||
| 113 | |||
| 114 | /** | ||
| 115 | * @AfterScenario | ||
| 116 | */ | ||
| 117 | public function afterResetAssets(ScenarioEvent $event) | ||
| 126 | |||
| 127 | /** | ||
| 128 | * Example: Given a "page" "Page 1" | ||
| 129 | * | ||
| 130 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)"$/ | ||
| 131 | */ | ||
| 132 | public function stepCreateRecord($type, $id) | ||
| 138 | |||
| 139 | /** | ||
| 140 | * Example: Given a "page" "Page 1" has the "content" "My content" | ||
| 141 | * | ||
| 142 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" has (?:(an|a|the) )"(?<field>.*)" "(?<value>.*)"$/ | ||
| 143 | */ | ||
| 144 | public function stepCreateRecordHasField($type, $id, $field, $value) | ||
| 162 | |||
| 163 | /** | ||
| 164 | * Example: Given a "page" "Page 1" with "URL"="page-1" and "Content"="my page 1" | ||
| 165 | * Example: Given the "page" "Page 1" has "URL"="page-1" and "Content"="my page 1" | ||
| 166 | * | ||
| 167 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" (?:(with|has)) (?<data>".*)$/ | ||
| 168 | */ | ||
| 169 | public function stepCreateRecordWithData($type, $id, $data) | ||
| 193 | |||
| 194 | /** | ||
| 195 | * Example: And the "page" "Page 2" has the following data | ||
| 196 | * | Content | <blink> | | ||
| 197 | * | My Property | foo | | ||
| 198 | * | My Boolean | bar | | ||
| 199 | * | ||
| 200 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" has the following data$/ | ||
| 201 | */ | ||
| 202 | public function stepCreateRecordWithTable($type, $id, $null, TableNode $fieldsTable) | ||
| 220 | |||
| 221 | /** | ||
| 222 | * Example: Given the "page" "Page 1.1" is a child of the "page" "Page1". | ||
| 223 | * Note that this change is not published by default | ||
| 224 | * | ||
| 225 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" is a (?<relation>[^\s]*) of (?:(an|a|the) )"(?<relationType>[^"]+)" "(?<relationId>[^"]+)"/ | ||
| 226 | */ | ||
| 227 | public function stepUpdateRecordRelation($type, $id, $relation, $relationType, $relationId) | ||
| 264 | |||
| 265 | /** | ||
| 266 | * Assign a type of object to another type of object. The base object will be created if it does not exist already. | ||
| 267 | * If the last part of the string (in the "X" relation) is omitted, then the first matching relation will be used. | ||
| 268 | * | ||
| 269 | * @example I assign the "TaxonomyTerm" "For customers" to the "Page" "Page1" | ||
| 270 | * @Given /^I assign (?:(an|a|the) )"(?<type>[^"]+)" "(?<value>[^"]+)" to (?:(an|a|the) )"(?<relationType>[^"]+)" "(?<relationId>[^"]+)"$/ | ||
| 271 | */ | ||
| 272 | public function stepIAssignObjToObj($type, $value, $relationType, $relationId) | ||
| 276 | |||
| 277 | /** | ||
| 278 | * Assign a type of object to another type of object. The base object will be created if it does not exist already. | ||
| 279 | * If the last part of the string (in the "X" relation) is omitted, then the first matching relation will be used. | ||
| 280 | * Assumption: one object has relationship (has_one, has_many or many_many ) with the other object | ||
| 281 | * | ||
| 282 | * @example I assign the "TaxonomyTerm" "For customers" to the "Page" "Page1" in the "Terms" relation | ||
| 283 | * @Given /^I assign (?:(an|a|the) )"(?<type>[^"]+)" "(?<value>[^"]+)" to (?:(an|a|the) )"(?<relationType>[^"]+)" "(?<relationId>[^"]+)" in the "(?<relationName>[^"]+)" relation$/ | ||
| 284 | */ | ||
| 285 | public function stepIAssignObjToObjInTheRelation($type, $value, $relationType, $relationId, $relationName) | ||
| 348 | |||
| 349 | /** | ||
| 350 | * Example: Given the "page" "Page 1" is not published | ||
| 351 | * | ||
| 352 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" is (?<state>[^"]*)$/ | ||
| 353 | */ | ||
| 354 | public function stepUpdateRecordState($type, $id, $state) | ||
| 388 | |||
| 389 | /** | ||
| 390 | * Accepts YAML fixture definitions similar to the ones used in SilverStripe unit testing. | ||
| 391 | * | ||
| 392 | * Example: Given there are the following member records: | ||
| 393 | * member1: | ||
| 394 | * Email: [email protected] | ||
| 395 | * member2: | ||
| 396 | * Email: [email protected] | ||
| 397 | * | ||
| 398 | * @Given /^there are the following ([^\s]*) records$/ | ||
| 399 | */ | ||
| 400 | public function stepThereAreTheFollowingRecords($dataObject, PyStringNode $string) | ||
| 410 | |||
| 411 | /** | ||
| 412 | * Example: Given a "member" "Admin" belonging to "Admin Group" | ||
| 413 | * | ||
| 414 | * @Given /^(?:(an|a|the) )"member" "(?<id>[^"]+)" belonging to "(?<groupId>[^"]+)"$/ | ||
| 415 | */ | ||
| 416 | public function stepCreateMemberWithGroup($id, $groupId) | ||
| 426 | |||
| 427 | /** | ||
| 428 | * Example: Given a "member" "Admin" belonging to "Admin Group" with "Email"="[email protected]" | ||
| 429 | * | ||
| 430 | * @Given /^(?:(an|a|the) )"member" "(?<id>[^"]+)" belonging to "(?<groupId>[^"]+)" with (?<data>.*)$/ | ||
| 431 | */ | ||
| 432 | public function stepCreateMemberWithGroupAndData($id, $groupId, $data) | ||
| 453 | |||
| 454 | /** | ||
| 455 | * Example: Given a "group" "Admin" with permissions "Access to 'Pages' section" and "Access to 'Files' section" | ||
| 456 | * | ||
| 457 | * @Given /^(?:(an|a|the) )"group" "(?<id>[^"]+)" (?:(with|has)) permissions (?<permissionStr>.*)$/ | ||
| 458 | */ | ||
| 459 | public function stepCreateGroupWithPermissions($id, $permissionStr) | ||
| 489 | |||
| 490 | /** | ||
| 491 | * Navigates to a record based on its identifier set during fixture creation, | ||
| 492 | * using its RelativeLink() method to map the record to a URL. | ||
| 493 | * Example: Given I go to the "page" "My Page" | ||
| 494 | * | ||
| 495 | * @Given /^I go to (?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)"/ | ||
| 496 | */ | ||
| 497 | public function stepGoToNamedRecord($type, $id) | ||
| 513 | |||
| 514 | |||
| 515 | /** | ||
| 516 | * Checks that a file or folder exists in the webroot. | ||
| 517 | * Example: There should be a file "assets/Uploads/test.jpg" | ||
| 518 | * | ||
| 519 | * @Then /^there should be a (?<type>(file|folder) )"(?<path>[^"]*)"/ | ||
| 520 | */ | ||
| 521 | public function stepThereShouldBeAFileOrFolder($type, $path) | ||
| 525 | |||
| 526 | /** | ||
| 527 | * Checks that a file exists in the asset store with a given filename and hash | ||
| 528 | * | ||
| 529 | * Example: there should be a filename "Uploads/test.jpg" with hash "59de0c841f" | ||
| 530 | * | ||
| 531 | * @Then /^there should be a filename "(?<filename>[^"]*)" with hash "(?<hash>[a-fA-Z0-9]+)"/ | ||
| 532 | */ | ||
| 533 | public function stepThereShouldBeAFileWithTuple($filename, $hash) | ||
| 538 | |||
| 539 | /** | ||
| 540 | * Replaces fixture references in values with their respective database IDs, | ||
| 541 | * with the notation "=><class>.<identifier>". Example: "=>Page.My Page". | ||
| 542 | * | ||
| 543 | * @Transform /^([^"]+)$/ | ||
| 544 | */ | ||
| 545 | public function lookupFixtureReference($string) | ||
| 561 | |||
| 562 | /** | ||
| 563 | * @Given /^(?:(an|a|the) )"(?<type>[^"]*)" "(?<id>[^"]*)" was (?<mod>(created|last edited)) "(?<time>[^"]*)"$/ | ||
| 564 | */ | ||
| 565 | public function aRecordWasLastEditedRelative($type, $id, $mod, $time) | ||
| 585 | |||
| 586 | /** | ||
| 587 | * Prepares a fixture for use | ||
| 588 | * | ||
| 589 | * @param string $class | ||
| 590 | * @param string $identifier | ||
| 591 | * @param array $data | ||
| 592 | * @return array Prepared $data with additional injected fields | ||
| 593 | */ | ||
| 594 | protected function prepareFixture($class, $identifier, $data = array()) | ||
| 601 | |||
| 602 | protected function prepareAsset($class, $identifier, $data = null) | ||
| 652 | |||
| 653 | /** | ||
| 654 | * | ||
| 655 | * @return AssetStore | ||
| 656 | */ | ||
| 657 | protected function getAssetStore() | ||
| 661 | |||
| 662 | /** | ||
| 663 | * Converts a natural language class description to an actual class name. | ||
| 664 |      * Respects {@link DataObject::$singular_name} variations. | ||
| 665 | * Example: "redirector page" -> "RedirectorPage" | ||
| 666 | * | ||
| 667 | * @param String | ||
| 668 | * @return String Class name | ||
| 669 | */ | ||
| 670 | protected function convertTypeToClass($type) | ||
| 692 | |||
| 693 | /** | ||
| 694 | * Updates an object with values, resolving aliases set through | ||
| 695 |      * {@link DataObject->fieldLabels()}. | ||
| 696 | * | ||
| 697 | * @param string $class Class name | ||
| 698 | * @param array $fields Map of field names or aliases to their values. | ||
| 699 | * @return array Map of actual object properties to their values. | ||
| 700 | */ | ||
| 701 | protected function convertFields($class, $fields) | ||
| 712 | |||
| 713 | protected function joinPaths() | ||
| 728 | } | ||
| 729 | 
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: