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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| 3 | abstract class HybridSessionAbstractTest extends SapphireTest { | 
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| 4 | |||
| 5 | 	public function setUp() { | 
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| 6 | parent::setUp();  | 
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| 7 | |||
| 8 | HybridSessionAbstractTest_TestCookieBackend::$override_headers_sent = false;  | 
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| 9 | |||
| 10 | Injector::nest();  | 
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| 11 | Injector::inst()->registerService(  | 
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| 12 | new HybridSessionAbstractTest_TestCookieBackend(),  | 
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| 13 | 'HybridSessionStore_Cookie'  | 
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| 14 | );  | 
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| 15 | |||
| 16 | 		SS_Datetime::set_mock_now('2010-03-15 12:00:00'); | 
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| 17 | |||
| 18 | 		if(get_class() === get_class($this)) { | 
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| 19 | 			$this->markTestSkipped("Skipping abstract test"); | 
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| 20 | $this->skipTest = true;  | 
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| 21 | }  | 
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| 22 | }  | 
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| 23 | |||
| 24 | 	public function tearDown() { | 
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| 25 | Injector::unnest();  | 
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| 26 | SS_Datetime::clear_mock_now();  | 
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| 27 | |||
| 28 | parent::tearDown();  | 
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| 29 | }  | 
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| 30 | |||
| 31 | /**  | 
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| 32 | * @return HybridSessionStore_Base  | 
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| 33 | */  | 
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| 34 | abstract protected function getStore();  | 
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| 35 | |||
| 36 | /**  | 
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| 37 | * Test how this store handles large volumes of data (>1000 characters)  | 
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| 38 | */  | 
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| 39 | View Code Duplication | 	public function testStoreLargeData() { | 
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| 56 | |||
| 57 | /**  | 
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| 58 | * Test storage of data  | 
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| 59 | */  | 
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| 60 | 	public function testStoreData() { | 
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| 86 | |||
| 87 | /**  | 
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| 88 | * Test expiry of data  | 
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| 89 | */  | 
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| 90 | 	public function testExpiry() { | 
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| 107 | }  | 
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| 108 | |||
| 127 | }  | 
            
You can fix this by adding a namespace to your class:
When choosing a vendor namespace, try to pick something that is not too generic to avoid conflicts with other libraries.