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 |
||
8 | trait ManagesStorageConnection |
||
9 | { |
||
10 | /** |
||
11 | * @return bool |
||
12 | */ |
||
13 | public function isReady() |
||
21 | |||
22 | /** |
||
23 | * Sometimes we want to gracefully check up on the cloud storage account without any exceptions |
||
24 | */ |
||
25 | public function ping() |
||
36 | |||
37 | /** |
||
38 | * @return bool |
||
39 | * @throws StorageUnavailableException |
||
40 | */ |
||
41 | public function verify() |
||
49 | |||
50 | /** |
||
51 | * @return mixed |
||
52 | */ |
||
53 | public function isConnected() |
||
57 | |||
58 | /** |
||
59 | * @return bool |
||
60 | */ |
||
61 | public function isEnabled() |
||
65 | |||
66 | /** |
||
67 | * @return bool |
||
68 | */ |
||
69 | public function isDisabled() |
||
73 | |||
74 | /** |
||
75 | * @return bool |
||
76 | */ |
||
77 | public function isTokenInvalid() |
||
81 | |||
82 | /** |
||
83 | * @param null $reason |
||
84 | * |
||
85 | * @return $this |
||
86 | */ |
||
87 | View Code Duplication | public function disable($reason = null) |
|
101 | |||
102 | /** |
||
103 | * @return $this |
||
104 | */ |
||
105 | View Code Duplication | public function enable() |
|
116 | } |
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.