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 |
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18 | class FixtureContext extends BehatContext |
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19 | { |
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20 | protected $context; |
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21 | |||
22 | /** |
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23 | * @var \FixtureFactory |
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24 | */ |
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25 | protected $fixtureFactory; |
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26 | |||
27 | /** |
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28 | * @var String Absolute path where file fixtures are located. |
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29 | * These will automatically get copied to their location |
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30 | * declare through the 'Given a file "..."' step defition. |
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31 | */ |
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32 | protected $filesPath; |
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33 | |||
34 | /** |
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35 | * @var String Tracks all files and folders created from fixtures, for later cleanup. |
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36 | */ |
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37 | protected $createdFilesPaths = array(); |
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38 | |||
39 | /** |
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40 | * @var array Stores the asset tuples. |
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41 | */ |
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42 | protected $createdAssets = array(); |
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43 | |||
44 | public function __construct(array $parameters) { |
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47 | |||
48 | public function getSession($name = null) { |
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51 | |||
52 | /** |
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53 | * @return \FixtureFactory |
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54 | */ |
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55 | public function getFixtureFactory() { |
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61 | |||
62 | /** |
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63 | * @param \FixtureFactory $factory |
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64 | */ |
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65 | public function setFixtureFactory(\FixtureFactory $factory) { |
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68 | |||
69 | /** |
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70 | * @param String |
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71 | */ |
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72 | public function setFilesPath($path) { |
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75 | |||
76 | /** |
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77 | * @return String |
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78 | */ |
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79 | public function getFilesPath() { |
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82 | |||
83 | /** |
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84 | * @BeforeScenario @database-defaults |
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85 | */ |
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86 | public function beforeDatabaseDefaults(ScenarioEvent $event) { |
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95 | |||
96 | /** |
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97 | * @AfterScenario |
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98 | */ |
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99 | public function afterResetDatabase(ScenarioEvent $event) { |
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102 | |||
103 | /** |
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104 | * @AfterScenario |
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105 | */ |
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106 | public function afterResetAssets(ScenarioEvent $event) { |
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114 | |||
115 | /** |
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116 | * Example: Given a "page" "Page 1" |
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117 | * |
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118 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)"$/ |
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119 | */ |
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120 | public function stepCreateRecord($type, $id) { |
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125 | |||
126 | /** |
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127 | * Example: Given a "page" "Page 1" has the "content" "My content" |
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128 | * |
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129 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" has (?:(an|a|the) )"(?<field>.*)" "(?<value>.*)"$/ |
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130 | */ |
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131 | public function stepCreateRecordHasField($type, $id, $field, $value) { |
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148 | |||
149 | /** |
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150 | * Example: Given a "page" "Page 1" with "URL"="page-1" and "Content"="my page 1" |
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151 | * Example: Given the "page" "Page 1" has "URL"="page-1" and "Content"="my page 1" |
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152 | * |
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153 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" (?:(with|has)) (?<data>".*)$/ |
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154 | */ |
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155 | public function stepCreateRecordWithData($type, $id, $data) { |
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178 | |||
179 | /** |
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180 | * Example: And the "page" "Page 2" has the following data |
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181 | * | Content | <blink> | |
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182 | * | My Property | foo | |
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183 | * | My Boolean | bar | |
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184 | * |
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185 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" has the following data$/ |
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186 | */ |
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187 | public function stepCreateRecordWithTable($type, $id, $null, TableNode $fieldsTable) { |
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204 | |||
205 | /** |
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206 | * Example: Given the "page" "Page 1.1" is a child of the "page" "Page1". |
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207 | * Note that this change is not published by default |
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208 | * |
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209 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" is a (?<relation>[^\s]*) of (?:(an|a|the) )"(?<relationType>[^"]+)" "(?<relationId>[^"]+)"/ |
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210 | */ |
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211 | public function stepUpdateRecordRelation($type, $id, $relation, $relationType, $relationId) { |
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245 | |||
246 | /** |
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247 | * Assign a type of object to another type of object. The base object will be created if it does not exist already. |
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248 | * If the last part of the string (in the "X" relation) is omitted, then the first matching relation will be used. |
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249 | * |
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250 | * @example I assign the "TaxonomyTerm" "For customers" to the "Page" "Page1" |
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251 | * @Given /^I assign (?:(an|a|the) )"(?<type>[^"]+)" "(?<value>[^"]+)" to (?:(an|a|the) )"(?<relationType>[^"]+)" "(?<relationId>[^"]+)"$/ |
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252 | */ |
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253 | public function stepIAssignObjToObj($type, $value, $relationType, $relationId) { |
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256 | |||
257 | /** |
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258 | * Assign a type of object to another type of object. The base object will be created if it does not exist already. |
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259 | * If the last part of the string (in the "X" relation) is omitted, then the first matching relation will be used. |
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260 | * Assumption: one object has relationship (has_one, has_many or many_many ) with the other object |
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261 | * |
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262 | * @example I assign the "TaxonomyTerm" "For customers" to the "Page" "Page1" in the "Terms" relation |
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263 | * @Given /^I assign (?:(an|a|the) )"(?<type>[^"]+)" "(?<value>[^"]+)" to (?:(an|a|the) )"(?<relationType>[^"]+)" "(?<relationId>[^"]+)" in the "(?<relationName>[^"]+)" relation$/ |
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264 | */ |
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265 | public function stepIAssignObjToObjInTheRelation($type, $value, $relationType, $relationId, $relationName) { |
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313 | |||
314 | /** |
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315 | * Example: Given the "page" "Page 1" is not published |
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316 | * |
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317 | * @Given /^(?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)" is (?<state>[^"]*)$/ |
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318 | */ |
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319 | public function stepUpdateRecordState($type, $id, $state) { |
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351 | |||
352 | /** |
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353 | * Accepts YAML fixture definitions similar to the ones used in SilverStripe unit testing. |
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354 | * |
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355 | * Example: Given there are the following member records: |
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356 | * member1: |
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357 | * Email: [email protected] |
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358 | * member2: |
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359 | * Email: [email protected] |
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360 | * |
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361 | * @Given /^there are the following ([^\s]*) records$/ |
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362 | */ |
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363 | public function stepThereAreTheFollowingRecords($dataObject, PyStringNode $string) { |
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372 | |||
373 | /** |
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374 | * Example: Given a "member" "Admin" belonging to "Admin Group" |
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375 | * |
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376 | * @Given /^(?:(an|a|the) )"member" "(?<id>[^"]+)" belonging to "(?<groupId>[^"]+)"$/ |
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377 | */ |
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378 | public function stepCreateMemberWithGroup($id, $groupId) { |
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385 | |||
386 | /** |
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387 | * Example: Given a "member" "Admin" belonging to "Admin Group" with "Email"="[email protected]" |
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388 | * |
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389 | * @Given /^(?:(an|a|the) )"member" "(?<id>[^"]+)" belonging to "(?<groupId>[^"]+)" with (?<data>.*)$/ |
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390 | */ |
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391 | public function stepCreateMemberWithGroupAndData($id, $groupId, $data) { |
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409 | |||
410 | /** |
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411 | * Example: Given a "group" "Admin" with permissions "Access to 'Pages' section" and "Access to 'Files' section" |
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412 | * |
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413 | * @Given /^(?:(an|a|the) )"group" "(?<id>[^"]+)" (?:(with|has)) permissions (?<permissionStr>.*)$/ |
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414 | */ |
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415 | public function stepCreateGroupWithPermissions($id, $permissionStr) { |
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442 | |||
443 | /** |
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444 | * Navigates to a record based on its identifier set during fixture creation, |
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445 | * using its RelativeLink() method to map the record to a URL. |
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446 | * Example: Given I go to the "page" "My Page" |
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447 | * |
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448 | * @Given /^I go to (?:(an|a|the) )"(?<type>[^"]+)" "(?<id>[^"]+)"/ |
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449 | */ |
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450 | public function stepGoToNamedRecord($type, $id) { |
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465 | |||
466 | |||
467 | /** |
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468 | * Checks that a file or folder exists in the webroot. |
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469 | * Example: There should be a file "assets/Uploads/test.jpg" |
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470 | * |
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471 | * @Then /^there should be a (?<type>(file|folder) )"(?<path>[^"]*)"/ |
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472 | */ |
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473 | public function stepThereShouldBeAFileOrFolder($type, $path) { |
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476 | |||
477 | /** |
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478 | * Replaces fixture references in values with their respective database IDs, |
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479 | * with the notation "=><class>.<identifier>". Example: "=>Page.My Page". |
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480 | * |
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481 | * @Transform /^([^"]+)$/ |
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482 | */ |
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483 | public function lookupFixtureReference($string) { |
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498 | |||
499 | /** |
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500 | * @Given /^(?:(an|a|the) )"(?<type>[^"]*)" "(?<id>[^"]*)" was (?<mod>(created|last edited)) "(?<time>[^"]*)"$/ |
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501 | */ |
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502 | public function aRecordWasLastEditedRelative($type, $id, $mod, $time) { |
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527 | |||
528 | /** |
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529 | * Prepares a fixture for use |
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530 | * |
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531 | * @param string $class |
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532 | * @param string $identifier |
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533 | * @param array $data |
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534 | * @return array Prepared $data with additional injected fields |
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535 | */ |
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536 | protected function prepareFixture($class, $identifier, $data = array()) { |
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542 | |||
543 | protected function prepareAsset($class, $identifier, $data = null) { |
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596 | |||
597 | /** |
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598 | * |
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599 | * @return AssetStore |
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600 | */ |
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601 | protected function getAssetStore() { |
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604 | |||
605 | /** |
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606 | * Converts a natural language class description to an actual class name. |
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607 | * Respects {@link DataObject::$singular_name} variations. |
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608 | * Example: "redirector page" -> "RedirectorPage" |
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609 | * |
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610 | * @param String |
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611 | * @return String Class name |
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612 | */ |
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613 | protected function convertTypeToClass($type) { |
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632 | |||
633 | /** |
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634 | * Updates an object with values, resolving aliases set through |
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635 | * {@link DataObject->fieldLabels()}. |
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636 | * |
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637 | * @param String Class name |
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638 | * @param Array Map of field names or aliases to their values. |
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639 | * @return Array Map of actual object properties to their values. |
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640 | */ |
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641 | protected function convertFields($class, $fields) { |
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652 | |||
653 | protected function joinPaths() { |
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661 | |||
662 | } |
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: