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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23 | class NodeCollectionTest extends AbstractTestCase |
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24 | { |
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25 | public function testIsCollection() |
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28 | } |
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29 | |||
30 | public function testCanAddADataNode() |
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31 | { |
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32 | $collection = new NodeCollection(); |
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33 | $node = m::mock(NodeInterface::class); |
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34 | static::assertSame($collection, $collection->add($node)); |
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35 | } |
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36 | |||
37 | public function testAddingANonDataNodeWillThrowAnException() |
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38 | { |
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39 | $node = m::mock('Graze\Extensible\ExtensibleInterface'); |
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40 | |||
41 | $this->expectException(InvalidArgumentException::class); |
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42 | |||
43 | $collection = new NodeCollection(); |
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44 | $collection->add($node); |
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45 | } |
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46 | |||
47 | public function testCallingApplyWillModifyTheContentsUsingReference() |
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48 | { |
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49 | $node = m::mock(NodeInterface::class); |
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50 | $node->shouldReceive('someMethod') |
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51 | ->once() |
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52 | ->andReturn(null); |
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53 | |||
54 | $collection = new NodeCollection(); |
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55 | $collection->add($node); |
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56 | |||
57 | $collection->apply(function ($item) { |
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58 | $item->someMethod(); |
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59 | }); |
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60 | |||
61 | $item = $collection->getAll()[0]; |
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62 | static::assertSame($node, $item); |
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63 | } |
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64 | |||
65 | public function testCallingApplyWillModifyTheContentsUsingReturnValue() |
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66 | { |
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67 | $node = m::mock(NodeInterface::class); |
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68 | $node->shouldReceive('someMethod') |
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69 | ->once() |
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70 | ->andReturn(null); |
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71 | |||
72 | $collection = new NodeCollection(); |
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73 | $collection->add($node); |
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74 | |||
75 | $collection->apply(function ($item) { |
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76 | $item->someMethod(); |
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77 | return $item; |
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78 | }); |
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79 | |||
80 | $item = $collection->getAll()[0]; |
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81 | static::assertSame($node, $item); |
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82 | } |
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83 | |||
84 | public function testFirstWithNoCallbackWillReturnTheFirstEntry() |
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85 | { |
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86 | $first = m::mock(NodeInterface::class); |
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87 | $second = m::mock(NodeInterface::class); |
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88 | |||
89 | $collection = new NodeCollection([$first, $second]); |
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90 | |||
91 | static::assertSame($first, $collection->first()); |
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92 | } |
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93 | |||
94 | public function testLastWithNoCallbackWillReturnTheFirstEntry() |
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95 | { |
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96 | $first = m::mock(NodeInterface::class); |
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97 | $second = m::mock(NodeInterface::class); |
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98 | |||
99 | $collection = new NodeCollection([$first, $second]); |
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100 | |||
101 | static::assertSame($second, $collection->last()); |
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102 | } |
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103 | |||
104 | public function testFirstWithCallbackWillReturnTheFirstThatMatches() |
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105 | { |
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106 | $first = m::mock(NodeInterface::class); |
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107 | $second = m::mock(NodeInterface::class); |
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108 | $third = m::mock(NodeInterface::class); |
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109 | |||
110 | $first->shouldReceive('thisOne') |
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111 | ->andReturn(false); |
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112 | $second->shouldReceive('thisOne') |
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113 | ->andReturn(true); |
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114 | $third->shouldReceive('thosOne') |
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115 | ->andReturn(true); |
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116 | |||
117 | $collection = new NodeCollection([$first, $second, $third]); |
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118 | |||
119 | static::assertSame($second, $collection->first(function ($item) { |
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120 | return $item->thisOne(); |
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121 | })); |
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122 | } |
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123 | |||
124 | public function testLastWithCallbackWillReturnTheFirstThatMatches() |
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125 | { |
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126 | $first = m::mock(NodeInterface::class); |
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127 | $second = m::mock(NodeInterface::class); |
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128 | $third = m::mock(NodeInterface::class); |
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129 | |||
130 | $first->shouldReceive('thisOne') |
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131 | ->andReturn(true); |
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132 | $second->shouldReceive('thisOne') |
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133 | ->andReturn(true); |
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134 | $third->shouldReceive('thisOne') |
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135 | ->andReturn(false); |
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136 | |||
137 | $collection = new NodeCollection([$first, $second, $third]); |
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138 | |||
139 | static::assertSame($second, $collection->last(function ($item) { |
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140 | return $item->thisOne(); |
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141 | })); |
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142 | } |
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143 | |||
144 | public function testFirstWithCallbackWillReturnDefaultIfNoMatchesAreFound() |
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145 | { |
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146 | $first = m::mock(NodeInterface::class); |
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147 | $second = m::mock(NodeInterface::class); |
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148 | $default = m::mock(NodeInterface::class); |
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149 | |||
150 | $first->shouldReceive('thisOne') |
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151 | ->andReturn(false); |
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152 | $second->shouldReceive('thisOne') |
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153 | ->andReturn(false); |
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154 | |||
155 | $collection = new NodeCollection([$first, $second]); |
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156 | |||
157 | static::assertSame($default, $collection->first(function ($item) { |
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158 | return $item->thisOne(); |
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159 | }, $default)); |
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160 | static::assertNull($collection->first(function ($item) { |
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161 | return $item->thisOne(); |
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162 | })); |
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163 | } |
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164 | |||
165 | public function testLastWithCallbackWillReturnDefaultIfNoMatchesAreFound() |
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166 | { |
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167 | $first = m::mock(NodeInterface::class); |
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168 | $second = m::mock(NodeInterface::class); |
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169 | $default = m::mock(NodeInterface::class); |
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170 | |||
171 | $first->shouldReceive('thisOne') |
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172 | ->andReturn(false); |
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173 | $second->shouldReceive('thisOne') |
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174 | ->andReturn(false); |
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175 | |||
176 | $collection = new NodeCollection([$first, $second]); |
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177 | |||
178 | static::assertSame($default, $collection->last(function ($item) { |
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179 | return $item->thisOne(); |
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180 | }, $default)); |
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181 | static::assertNull($collection->last(function ($item) { |
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182 | return $item->thisOne(); |
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183 | })); |
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184 | } |
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185 | |||
186 | public function testCloneWillCloneTheChildObjects() |
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187 | { |
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188 | $first = m::mock(NodeInterface::class); |
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189 | $second = m::mock(NodeInterface::class); |
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190 | |||
191 | $collection = new NodeCollection([$first, $second]); |
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192 | $collection2 = $collection->getClone(); |
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193 | |||
194 | static::assertNotSame($collection, $collection2); |
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195 | static::assertEquals($collection->count(), $collection2->count()); |
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196 | for ($i = 0; $i < $collection->count(); $i++) { |
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197 | static::assertNotSame($collection->getAll()[$i], $collection2->getAll()[$i]); |
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198 | } |
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199 | } |
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200 | |||
201 | public function testToString() |
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205 | } |
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206 | } |
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207 |
This check compares calls to functions or methods with their respective definitions. If the call has more arguments than are defined, it raises an issue.
If a function is defined several times with a different number of parameters, the check may pick up the wrong definition and report false positives. One codebase where this has been known to happen is Wordpress. Please note the @ignore annotation hint above.