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:
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| 16 | View Code Duplication | class ResolverTestReturnsAllBundlesIfNoBundleIsRequestedDebugProjectContainer extends Container |
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| 18 | private $parameters; |
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| 19 | private $targetDirs = array(); |
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| 21 | /** |
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| 22 | * Constructor. |
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| 24 | public function __construct() |
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| 38 | * {@inheritdoc} |
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| 40 | public function compile() |
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| 48 | public function isFrozen() |
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| 56 | public function getParameter($name) |
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| 70 | public function hasParameter($name) |
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| 80 | public function setParameter($name, $value) |
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| 88 | public function getParameterBag() |
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| 98 | * Gets the default parameters. |
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| 99 | * |
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| 100 | * @return array An array of the default parameters |
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| 102 | protected function getDefaultParameters() |
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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: