Complex classes like RevisionPrinter 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 RevisionPrinter, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 21 | class RevisionPrinter |
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| 22 | { |
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| 23 | |||
| 24 | const COLUMN_FULL_MESSAGE = 1; |
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| 25 | |||
| 26 | const COLUMN_DETAILS = 2; |
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| 27 | |||
| 28 | const COLUMN_SUMMARY = 3; |
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| 29 | |||
| 30 | const COLUMN_REFS = 4; |
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| 31 | |||
| 32 | const COLUMN_MERGE_ORACLE = 5; |
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| 33 | |||
| 34 | const COLUMN_MERGE_STATUS = 6; |
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| 35 | |||
| 36 | /** |
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| 37 | * Date helper. |
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| 38 | * |
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| 39 | * @var DateHelper |
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| 40 | */ |
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| 41 | private $_dateHelper; |
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| 42 | |||
| 43 | /** |
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| 44 | * Output helper. |
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| 45 | * |
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| 46 | * @var OutputHelper |
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| 47 | */ |
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| 48 | private $_outputHelper; |
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| 49 | |||
| 50 | /** |
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| 51 | * Columns. |
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| 52 | * |
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| 53 | * @var array |
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| 54 | */ |
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| 55 | private $_columns = array(); |
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| 56 | |||
| 57 | /** |
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| 58 | * Merge conflict regexps. |
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| 59 | * |
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| 60 | * @var array |
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| 61 | */ |
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| 62 | private $_mergeConflictRegExps = array(); |
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| 63 | |||
| 64 | /** |
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| 65 | * Log message limit. |
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| 66 | * |
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| 67 | * @var integer |
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| 68 | */ |
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| 69 | private $_logMessageLimit = 68; |
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| 70 | |||
| 71 | /** |
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| 72 | * Current revision (e.g. in a working copy). |
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| 73 | * |
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| 74 | * @var integer|null |
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| 75 | */ |
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| 76 | private $_currentRevision; |
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| 77 | |||
| 78 | /** |
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| 79 | * Creates instance of revision printer. |
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| 80 | * |
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| 81 | * @param DateHelper $date_helper Date helper. |
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| 82 | * @param OutputHelper $output_helper Output helper. |
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| 83 | */ |
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| 84 | 1 | public function __construct(DateHelper $date_helper, OutputHelper $output_helper) |
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| 91 | |||
| 92 | /** |
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| 93 | * Resets state. |
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| 94 | * |
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| 95 | * @return void |
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| 96 | */ |
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| 97 | 1 | private function _resetState() |
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| 103 | |||
| 104 | /** |
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| 105 | * Adds column to the output. |
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| 106 | * |
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| 107 | * @param integer $column Column. |
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| 108 | * |
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| 109 | * @return self |
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| 110 | */ |
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| 111 | public function withColumn($column) |
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| 117 | |||
| 118 | /** |
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| 119 | * Sets merge conflict regexps. |
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| 120 | * |
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| 121 | * @param array $merge_conflict_regexps Merge conflict regexps. |
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| 122 | * |
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| 123 | * @return void |
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| 124 | */ |
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| 125 | public function setMergeConflictRegExps(array $merge_conflict_regexps) |
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| 129 | |||
| 130 | /** |
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| 131 | * Sets log message limit. |
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| 132 | * |
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| 133 | * @param integer $log_message_limit Log message limit. |
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| 134 | * |
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| 135 | * @return void |
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| 136 | */ |
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| 137 | public function setLogMessageLimit($log_message_limit) |
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| 141 | |||
| 142 | /** |
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| 143 | * Sets current revision. |
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| 144 | * |
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| 145 | * @param integer $revision Revision. |
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| 146 | * |
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| 147 | * @return void |
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| 148 | */ |
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| 149 | public function setCurrentRevision($revision) |
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| 153 | |||
| 154 | /** |
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| 155 | * Prints revisions. |
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| 156 | * |
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| 157 | * @param RevisionLog $revision_log Revision log. |
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| 158 | * @param array $revisions Revisions. |
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| 159 | * @param OutputInterface $output Output. |
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| 160 | * |
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| 161 | * @return void |
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| 162 | */ |
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| 163 | public function printRevisions(RevisionLog $revision_log, array $revisions, OutputInterface $output) |
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| 302 | |||
| 303 | /** |
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| 304 | * Returns log message. |
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| 305 | * |
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| 306 | * @param boolean $with_full_message Show commit message without truncation. |
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| 307 | * @param array $revision_data Revision data. |
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| 308 | * |
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| 309 | * @return string |
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| 310 | */ |
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| 311 | private function _generateLogMessageColumn($with_full_message, array $revision_data) |
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| 338 | |||
| 339 | /** |
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| 340 | * Generates change summary for a revision. |
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| 341 | * |
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| 342 | * @param array $revision_paths Revision paths. |
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| 343 | * |
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| 344 | * @return string |
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| 345 | */ |
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| 346 | private function _generateSummaryColumn(array $revision_paths) |
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| 374 | |||
| 375 | /** |
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| 376 | * Returns merge conflict path predictions. |
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| 377 | * |
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| 378 | * @param array $revision_paths Revision paths. |
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| 379 | * |
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| 380 | * @return array |
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| 381 | */ |
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| 382 | private function _getMergeConflictPrediction(array $revision_paths) |
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| 400 | |||
| 401 | /** |
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| 402 | * Generates content for "Merged Via" cell content. |
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| 403 | * |
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| 404 | * @param array $merged_via Merged Via. |
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| 405 | * @param array $revisions_merged_via_refs Merged Via Refs. |
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| 406 | * |
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| 407 | * @return string |
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| 408 | */ |
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| 409 | private function _generateMergedViaColumn(array $merged_via, array $revisions_merged_via_refs) |
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| 430 | |||
| 431 | /** |
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| 432 | * Generates details row content. |
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| 433 | * |
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| 434 | * @param integer $revision Revision. |
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| 435 | * @param array $revisions_refs Refs. |
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| 436 | * @param array $revision_paths Revision paths. |
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| 437 | * @param array $merge_conflict_prediction Merge conflict prediction. |
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| 438 | * @param string $project_path Project path. |
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| 439 | * |
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| 440 | * @return string |
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| 441 | */ |
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| 442 | private function _generateDetailsRowContent( |
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| 489 | |||
| 490 | /** |
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| 491 | * Returns path cut off regexp. |
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| 492 | * |
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| 493 | * @param string $project_path Project path. |
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| 494 | * @param array $refs Refs. |
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| 495 | * |
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| 496 | * @return string |
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| 497 | */ |
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| 498 | protected function getPathCutOffRegExp($project_path, array $refs) |
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| 512 | |||
| 513 | /** |
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| 514 | * Returns relative path to "svn log" returned path. |
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| 515 | * |
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| 516 | * @param array $path_data Path data. |
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| 517 | * @param string $path_key Path key. |
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| 518 | * @param string $path_cut_off_regexp Path cut off regexp. |
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| 519 | * |
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| 520 | * @return string |
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| 521 | */ |
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| 522 | private function _getRelativeLogPath(array $path_data, $path_key, $path_cut_off_regexp) |
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| 532 | |||
| 533 | } |
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| 534 |
If you define a variable conditionally, it can happen that it is not defined for all execution paths.
Let’s take a look at an example:
In the above example, the variable $x is defined if you pass “foo” or “bar” as argument for $a. However, since the switch statement has no default case statement, if you pass any other value, the variable $x would be undefined.
Available Fixes
Check for existence of the variable explicitly:
Define a default value for the variable:
Add a value for the missing path: