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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| 11 | * Filters $value to an integer strictly. |
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| 12 | * |
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| 13 | * $value must be an int or contain all digits, optionally prepended by a '+' or '-' and optionally surrounded by |
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| 14 | * whitespace to pass the filter. |
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| 15 | * |
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| 16 | * The return value is the int, as expected by the \TraderInteractive\Filterer class. |
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| 17 | * |
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| 18 | * @param string|int $value the value to make an integer |
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| 19 | * @param bool $allowNull Set to true if NULL values are allowed. The filtered result of a NULL value is NULL |
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| 20 | * @param int $minValue The minimum acceptable value |
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| 21 | * @param int $maxValue The maximum acceptable value |
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| 22 | * |
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| 23 | * @return int|null The filtered value |
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| 24 | * |
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| 25 | * @throws \InvalidArgumentException if $allowNull is not a boolean |
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| 26 | * @throws \InvalidArgumentException if $minValue is not null and not an int |
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| 27 | * @throws \InvalidArgumentException if $maxValue is not an int |
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| 28 | * @throws Exception if $value string length is zero |
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| 29 | * @throws Exception if $value does not contain all digits, optionally prepended by a '+' or '-' and optionally |
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| 30 | * surrounded by whitespace |
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| 31 | * @throws Exception if $value was greater than a max int of PHP_INT_MAX |
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| 32 | * @throws Exception if $value was less than a min int of ~PHP_INT_MAX |
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| 33 | * @throws Exception if $value is not a string |
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| 34 | * @throws Exception if $value is less than $minValue |
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| 35 | * @throws Exception if $value is greater than $maxValue |
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| 36 | */ |
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| 37 | public static function filter($value, bool $allowNull = false, int $minValue = null, int $maxValue = PHP_INT_MAX) |
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| 93 | } |
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| 94 |
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.