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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| 17 | abstract class PHPCompatibility_AbstractNewFeatureSniff extends PHPCompatibility_AbstractComplexVersionSniff  | 
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| 18 | { | 
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| 19 | |||
| 20 | |||
| 21 | /**  | 
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| 22 | * Determine whether an error/warning should be thrown for an item based on collected information.  | 
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| 23 | *  | 
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| 24 | * @param array $errorInfo Detail information about an item.  | 
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| 25 | *  | 
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| 26 | * @return bool  | 
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| 27 | */  | 
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| 28 | protected function shouldThrowError(array $errorInfo)  | 
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| 32 | |||
| 33 | |||
| 34 | /**  | 
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| 35 | * Retrieve the relevant detail (version) information for use in an error message.  | 
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| 36 | *  | 
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| 37 | * @param array $itemArray Version and other information about the item.  | 
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| 38 | * @param array $itemInfo Base information about the item.  | 
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| 39 | *  | 
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| 40 | * @return array  | 
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| 41 | */  | 
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| 42 | public function getErrorInfo(array $itemArray, array $itemInfo)  | 
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| 63 | |||
| 64 | |||
| 65 | /**  | 
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| 66 | * Get the error message template for this sniff.  | 
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| 67 | *  | 
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| 68 | * @return string  | 
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| 69 | */  | 
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| 70 | protected function getErrorMsgTemplate()  | 
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| 74 | |||
| 75 | |||
| 76 | /**  | 
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| 77 | * Generates the error or warning for this item.  | 
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| 78 | *  | 
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| 79 | * @param PHP_CodeSniffer_File $phpcsFile The file being scanned.  | 
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| 80 | * @param int $stackPtr The position of the relevant token in  | 
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| 81 | * the stack.  | 
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| 82 | * @param array $itemInfo Base information about the item.  | 
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| 83 | * @param array $errorInfo Array with detail (version) information  | 
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| 84 | * relevant to the item.  | 
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| 85 | *  | 
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| 86 | * @return void  | 
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| 87 | */  | 
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| 88 | public function addError(PHP_CodeSniffer_File $phpcsFile, $stackPtr, array $itemInfo, array $errorInfo)  | 
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| 104 | |||
| 105 | |||
| 106 | }//end class  | 
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| 107 | 
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.