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 // phpcs:ignore WordPress.Files.FileName |
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| 15 | class Test_Version_Loading_From_Manifests extends TestCase { |
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| 16 | |||
| 17 | /** |
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| 18 | * A manifest handler. |
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| 19 | * |
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| 20 | * @var Manifest_Reader |
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| 21 | */ |
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| 22 | private $manifest_handler; |
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| 23 | |||
| 24 | /** |
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| 25 | * Setup runs before each test. |
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| 26 | * |
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| 27 | * @before |
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| 28 | */ |
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| 29 | public function set_up() { |
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| 30 | $this->manifest_handler = new Manifest_Reader( new Version_Selector() ); |
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| 31 | } |
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| 32 | |||
| 33 | /** |
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| 34 | * Tests that the classmap manifest from a single plugin can be handled correctly. |
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| 35 | */ |
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| 36 | View Code Duplication | public function test_classmap() { |
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| 55 | |||
| 56 | /** |
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| 57 | * Tests that the PSR-4 manifest from a single plugin can be handled correctly. |
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| 58 | */ |
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| 59 | View Code Duplication | public function test_psr4() { |
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| 78 | |||
| 79 | /** |
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| 80 | * Tests that the filemap manifest from a single plugin can be handled correctly. |
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| 81 | * |
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| 82 | * @preserveGlobalState disabled |
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| 83 | * @runInSeparateProcess |
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| 84 | */ |
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| 85 | public function test_filemap() { |
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| 105 | } |
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| 106 |
Let’s assume that you have a directory layout like this:
. |-- OtherDir | |-- Bar.php | `-- Foo.php `-- SomeDir `-- Foo.phpand let’s assume the following content of
Bar.php:If both files
OtherDir/Foo.phpandSomeDir/Foo.phpare loaded in the same runtime, you will see a PHP error such as the following:PHP Fatal error: Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.phpHowever, as
OtherDir/Foo.phpdoes not necessarily have to be loaded and the error is only triggered if it is loaded beforeOtherDir/Bar.php, this problem might go unnoticed for a while. In order to prevent this error from surfacing, you must import the namespace with a different alias: