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 xsDoubleTest extends \PHPUnit_Framework_TestCase  | 
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| 10 | { | 
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| 11 | /**  | 
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| 12 | * Sets up the fixture, for example, opens a network connection.  | 
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| 13 | * This method is called before a test is executed.  | 
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| 14 | */  | 
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| 15 | protected function setUp()  | 
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| 19 | |||
| 20 | /**  | 
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| 21 | * Tears down the fixture, for example, closes a network connection.  | 
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| 22 | * This method is called after a test is executed.  | 
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| 23 | */  | 
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| 24 | protected function tearDown()  | 
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| 28 | |||
| 29 | /**  | 
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| 30 | * @dataProvider testxsDoubleValidDataProvider  | 
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| 31 | */  | 
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| 32 | public function testxsDoubleValid($input, $message)  | 
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| 41 | |||
| 42 | public function testxsDoubleValidDataProvider()  | 
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| 56 | |||
| 57 | /**  | 
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| 58 | * @dataProvider testxsDoubleInvalidDataProvider  | 
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| 59 | */  | 
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| 60 | View Code Duplication | public function testxsDoubleInvalid($input, $message)  | 
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| 70 | |||
| 71 | public function testxsDoubleInvalidDataProvider()  | 
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| 80 | }  | 
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| 81 | 
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.