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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7 | class SlugTest extends PHPUnit_Framework_TestCase |
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8 | { |
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9 | /** |
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10 | * If the given Slug is valid validateSlug should not throw an exception |
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11 | * |
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12 | * @test |
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13 | * @dataProvider getValidSlugs |
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14 | * |
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15 | * @param string $sku A Slug |
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16 | */ |
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17 | public function validateSlug_validSlugs_NoExceptionIsThrown($sku) |
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18 | { |
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19 | // act |
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20 | try { |
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21 | |||
22 | new Slug($sku); |
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23 | $exceptionThrown = false; |
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24 | |||
25 | } catch (Exception $validationException) { |
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26 | $exceptionThrown = true; |
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27 | } |
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28 | |||
29 | // assert |
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30 | $this->assertFalse($exceptionThrown, "validateSlug('$sku') should not have thrown an exception"); |
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31 | } |
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32 | |||
33 | /** |
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34 | * If the given Slug is invalid validateSlug should throw an exception |
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35 | * |
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36 | * @test |
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37 | * @dataProvider getInvalidSlugs |
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38 | * |
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39 | * @param string $sku A Slug |
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40 | * @param string $expectedExceptionMessage The expected exception message |
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41 | */ |
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42 | public function validateSlug_invalidSlugs_ExceptionIsThrown($sku, $expectedExceptionMessage) |
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43 | { |
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44 | // act |
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45 | $exceptionThrown = false; |
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46 | try { |
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47 | |||
48 | new Slug($sku); |
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49 | $exceptionThrown = false; |
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50 | |||
51 | } catch (Exception $validationException) { |
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52 | |||
53 | // assert |
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54 | $exceptionThrown = true; |
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55 | $this->assertContains($expectedExceptionMessage, $validationException->getMessage(), |
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56 | "validateSlug('$sku') should have thrown an exception with the message: $expectedExceptionMessage"); |
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57 | |||
58 | } |
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59 | |||
60 | // assert |
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61 | $this->assertTrue($exceptionThrown, "validateSlug('$sku') should have thrown an exception"); |
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62 | } |
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63 | |||
64 | /** |
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65 | * Get a list of valid Slugs |
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66 | * |
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67 | * @return array |
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68 | */ |
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69 | public static function getValidSlugs() |
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70 | { |
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71 | return [ |
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72 | ["abcdefghijklmnopqrstuvwxyz012345abcdefghijklmnopqrstuvwxyz012345"], // max length <= 32 |
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73 | ["abcdefghijklmnopqrstuvwxyz"], // the whole alphabet |
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74 | ["123456789"], // only digits |
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75 | ["00000111111111"], // leading zeros |
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76 | ["a-product"], // dashes |
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77 | ["product1"], // characters and digits |
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78 | ["product112345678"], // characters and digits |
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79 | ["product-1"], |
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80 | ["product-112345678"], |
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81 | ["ab"], // min length >= 2 |
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82 | ["12"], // min length >= 2 |
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83 | ["abc-dfg"], |
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84 | ["abc_dfg"], |
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85 | ["abc:dfg"], |
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86 | ["abc.dfg"], |
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87 | ["abc,dfg"], |
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88 | ["abc+dfg"], |
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89 | ["ABC_xyz"], |
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90 | ['Åre'], // Swedish umlaut |
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91 | ['Öresund'], // German umlaut |
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92 | ['наушник'], // Russian |
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93 | ['이어폰'], // Korean |
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94 | ]; |
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95 | } |
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96 | |||
97 | /** |
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98 | * Get a list of invalid Slugs |
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99 | * |
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100 | * @return array |
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101 | */ |
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102 | public static function getInvalidSlugs() |
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103 | { |
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104 | // format: [ "sku", "expected exception messages" ] |
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105 | return [ |
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106 | // empty |
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107 | ["", "empty"], |
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108 | |||
109 | // white space |
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110 | [" product", "white space"], |
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111 | ["product ", "white space"], |
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112 | [" product ", "white space"], |
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113 | ["pro duct", "white space"], |
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114 | |||
115 | // invalid characters |
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116 | ['7$tshirt', "invalid characters"], // Dollar sign |
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117 | ['product(1)', "invalid characters"], |
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118 | ['product§1', "invalid characters"], |
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119 | ['👃-spray', "invalid characters"], // nose emoji |
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120 | |||
121 | // minimum length |
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122 | ["a", "too short"], |
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123 | ["1", "too short"], |
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124 | ["0", "too short"], |
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125 | |||
126 | // maximum length |
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127 | ["abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz0123456789", "too long"], |
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128 | |||
129 | ]; |
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130 | } |
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131 | } |
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132 |