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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41 | class FlatContainer extends Container |
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42 | { |
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43 | const DELIMITER = '.'; |
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44 | |||
45 | /** |
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46 | * @param string $key |
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47 | * |
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48 | * @return mixed|null |
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49 | */ |
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50 | private function getChild($key) |
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62 | |||
63 | /** |
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64 | * @param string $key |
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65 | * |
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66 | * @return string[] split the key into everything up to the last delimiter, and the last key |
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67 | */ |
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68 | private function splitToLast($key) |
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76 | |||
77 | /** |
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78 | * @param string $key |
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79 | * |
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80 | * @return bool |
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81 | */ |
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82 | View Code Duplication | public function has($key) |
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89 | |||
90 | /** |
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91 | * @param string $key |
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92 | * |
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93 | * @return mixed|null |
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94 | */ |
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95 | View Code Duplication | public function get($key) |
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103 | |||
104 | /** |
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105 | * @param string $key |
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106 | * @param mixed $value |
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107 | * |
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108 | * @return ContainerInterface |
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109 | */ |
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110 | public function set($key, $value) |
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114 | |||
115 | /** |
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116 | * @param string $key |
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117 | * @param mixed $value |
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118 | * |
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119 | * @return ContainerInterface |
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120 | */ |
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121 | protected function doSet($key, $value) |
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142 | |||
143 | /** |
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144 | * @param string $key |
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145 | * |
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146 | * @return ContainerInterface |
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147 | */ |
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148 | public function remove($key) |
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152 | |||
153 | /** |
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154 | * @param string $key |
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155 | * |
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156 | * @return ContainerInterface |
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157 | */ |
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158 | protected function doRemove($key) |
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179 | } |
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180 |
This check looks for multiple assignments in successive lines of code. It will report an issue if the operators are not in a straight line.
To visualize
will produce issues in the first and second line, while this second example
will produce no issues.