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:
| 1 | <?php |
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| 9 | class Collection extends BaseCollection |
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| 10 | { |
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| 11 | /** |
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| 12 | * Cassandra rows instance |
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| 13 | * |
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| 14 | * @var \Cassandra\Rows |
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| 15 | */ |
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| 16 | private $rows; |
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| 17 | |||
| 18 | /** |
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| 19 | * Set Cassandra rows instance related to the |
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| 20 | * collection items. |
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| 21 | * |
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| 22 | * Required for fetching next pages |
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| 23 | * |
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| 24 | * @param Rows $rows |
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| 25 | * |
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| 26 | * @return $this |
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| 27 | */ |
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| 28 | 56 | public function setRowsInstance(Rows $rows) |
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| 34 | |||
| 35 | /** |
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| 36 | * Next page token |
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| 37 | * |
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| 38 | * @return mixed |
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| 39 | */ |
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| 40 | 3 | public function getNextPageToken() |
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| 48 | |||
| 49 | /** |
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| 50 | * Last page indicator |
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| 51 | * @return bool |
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| 52 | */ |
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| 53 | 6 | public function isLastPage() |
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| 61 | |||
| 62 | /** |
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| 63 | * Get next page |
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| 64 | * |
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| 65 | * @return Collection |
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| 66 | */ |
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| 67 | 5 | public function nextPage() |
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| 81 | |||
| 82 | /** |
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| 83 | * Get rows instance |
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| 84 | * |
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| 85 | * @return \Cassandra\Rows |
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| 86 | */ |
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| 87 | 50 | public function getRows() |
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| 91 | |||
| 92 | /** |
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| 93 | * Update current collection with results from |
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| 94 | * the next page |
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| 95 | * |
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| 96 | * @return Collection |
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| 97 | */ |
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| 98 | 2 | public function appendNextPage() |
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| 109 | |||
| 110 | /** |
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| 111 | * Merge the collection with the given items. |
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| 112 | * |
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| 113 | * @param \ArrayAccess|array $items |
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| 114 | * @return static |
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| 115 | */ |
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| 116 | 2 | public function merge($items) |
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| 126 | |||
| 127 | /** |
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| 128 | * Reload a fresh model instance from the database for all the entities. |
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| 129 | * |
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| 130 | * @param array|string $with |
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| 131 | * @return static |
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| 132 | */ |
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| 133 | 4 | public function fresh($with = []) |
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| 154 | |||
| 155 | /** |
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| 156 | * Diff the collection with the given items. |
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| 157 | * |
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| 158 | * @param \ArrayAccess|array $items |
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| 159 | * @return static |
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| 160 | */ |
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| 161 | 1 | View Code Duplication | public function diff($items) |
| 175 | |||
| 176 | /** |
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| 177 | * Intersect the collection with the given items. |
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| 178 | * |
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| 179 | * @param \ArrayAccess|array $items |
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| 180 | * @return static |
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| 181 | */ |
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| 182 | 1 | View Code Duplication | public function intersect($items) |
| 196 | |||
| 197 | /** |
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| 198 | * Get a dictionary keyed by primary keys. |
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| 199 | * |
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| 200 | * @param \ArrayAccess|array|null $items |
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| 201 | * @return array |
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| 202 | */ |
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| 203 | 11 | public function getDictionary($items = null) |
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| 215 | } |
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| 216 |
This check looks for variable assignements that are either overwritten by other assignments or where the variable is not used subsequently.
Both the
$myVarassignment in line 1 and the$higherassignment in line 2 are dead. The first because$myVaris never used and the second because$higheris always overwritten for every possible time line.