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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| 20 | class ISBNTest extends PHPUnit_Framework_TestCase  | 
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| 21 | { | 
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| 22 | /**  | 
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| 23 | * @var \eZ\Publish\Core\Persistence\Legacy\Content\FieldValue\Converter\ISBNConverter  | 
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| 24 | */  | 
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| 25 | protected $converter;  | 
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| 26 | |||
| 27 | protected function setUp()  | 
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| 31 | |||
| 32 | /**  | 
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| 33 | * @dataProvider providerForTestToFieldDefinition  | 
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| 34 | *  | 
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| 35 | * @covers \eZ\Publish\Core\Persistence\Legacy\Content\FieldValue\Converter\ISBNConverter::toFieldDefinition  | 
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| 36 | */  | 
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| 37 | public function testToFieldDefinition($dataInt, $excpectedIsbn13Value)  | 
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| 50 | |||
| 51 | View Code Duplication | public function providerForTestToFieldDefinition()  | 
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| 59 | }  | 
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| 60 |