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 |
||
21 | trait SetterTrait |
||
22 | { |
||
23 | /** |
||
24 | * Set permission. |
||
25 | * @param string $name |
||
26 | * @param string $description |
||
27 | * @return Item |
||
28 | */ |
||
29 | 7 | public function setPermission($name, $description = null) |
|
39 | |||
40 | /** |
||
41 | * Set role. |
||
42 | * @param string $name |
||
43 | * @param string $description |
||
44 | * @return Item |
||
45 | */ |
||
46 | 7 | public function setRole($name, $description = null) |
|
56 | |||
57 | /** |
||
58 | * Set child. |
||
59 | * @param string|Item $parent |
||
60 | * @param string|Item $child |
||
61 | * @return bool |
||
62 | */ |
||
63 | 7 | public function setChild($parent, $child) |
|
64 | { |
||
65 | 7 | View Code Duplication | if (is_string($parent)) { |
66 | 7 | $name = $parent; |
|
67 | 7 | $parent = $this->getItem($parent); |
|
68 | 7 | if (is_null($parent)) { |
|
69 | throw new InvalidParamException("Unknown parent:$name at setChild"); |
||
70 | } |
||
71 | 7 | } |
|
72 | 7 | View Code Duplication | if (is_string($child)) { |
73 | $name = $child; |
||
74 | $child = $this->getItem($child); |
||
75 | if (is_null($child)) { |
||
76 | throw new InvalidParamException("Unknown child:$name at setChild"); |
||
77 | } |
||
78 | } |
||
79 | 7 | if (isset($this->children[$parent->name][$child->name])) { |
|
80 | return false; |
||
81 | } |
||
82 | |||
83 | 7 | return $this->addChild($parent, $child); |
|
84 | } |
||
85 | |||
86 | /** |
||
87 | * Assigns an item (role or permission) to a user. |
||
88 | * @param string|Item $item |
||
89 | * @param string|integer $userId the user ID (see [[\yii\web\User::id]]) |
||
90 | * @throws \Exception when given wrong item name |
||
91 | * @return Assignment the assignment object |
||
92 | */ |
||
93 | 14 | public function setAssignment($item, $userId) |
|
94 | { |
||
95 | 14 | if (is_string($item)) { |
|
96 | 14 | $item = $this->findItem($item); |
|
97 | 14 | } |
|
98 | 14 | if (isset($this->assignments[$userId][$item->name])) { |
|
99 | return $this->assignments[$userId][$item->name]; |
||
100 | } |
||
101 | |||
102 | 14 | return $this->assign($item, $userId); |
|
103 | } |
||
104 | |||
105 | 14 | protected function findItem($name, $description = null) |
|
117 | |||
118 | /** |
||
119 | * Assigns items to a user. |
||
120 | * @param string|array $items |
||
121 | * @param string|integer $userId |
||
122 | */ |
||
123 | 4 | public function setAssignments($items, $userId) |
|
124 | { |
||
125 | 4 | if (is_string($items)) { |
|
126 | 4 | $items = explode(',', $items); |
|
127 | 4 | } |
|
128 | 4 | foreach ($items as $item) { |
|
129 | 4 | $this->setAssignment($item, $userId); |
|
130 | 4 | } |
|
131 | 4 | } |
|
132 | |||
133 | /** |
||
134 | * Returns all assignments in the system. |
||
135 | * @return array |
||
136 | */ |
||
137 | public function getAllAssignments() |
||
141 | |||
142 | /** |
||
143 | * Returns all items in the system. |
||
144 | * @return array |
||
145 | */ |
||
146 | 14 | public function getAllItems() |
|
150 | } |
||
151 |
This check looks for methods that are used by a trait but not required by it.
To illustrate, let’s look at the following code example
The trait
Idable
provides a methodequalsId
that in turn relies on the methodgetId()
. If this method does not exist on a class mixing in this trait, the method will fail.Adding the
getId()
as an abstract method to the trait will make sure it is available.