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 | trait ManagesContacts |
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12 | { |
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13 | /** |
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14 | * Get all contacts. |
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15 | * |
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16 | * @return array |
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17 | */ |
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18 | public function contacts() |
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26 | |||
27 | /** |
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28 | * Find contact by email. |
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29 | * |
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30 | * @param string $email |
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31 | * |
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32 | * @return Contact|null |
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33 | */ |
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34 | public function findContact($email) |
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44 | |||
45 | /** |
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46 | * Find contact by ID. |
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47 | * |
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48 | * @param int $id |
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49 | * |
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50 | * @return Contact|null |
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51 | */ |
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52 | public function findContactById($id) |
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57 | |||
58 | /** |
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59 | * Create new contact. |
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60 | * |
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61 | * @param string $email |
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62 | * @param string $firstName |
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63 | * @param string $lastName |
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64 | * @param int|null $orgid |
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65 | * |
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66 | * @return Contact|null |
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67 | */ |
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68 | public function createContact($email, $firstName, $lastName, $orgid = null) |
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77 | |||
78 | /** |
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79 | * Find or create a contact. |
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80 | * |
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81 | * @param string $email |
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82 | * @param string $firstName |
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83 | * @param string $lastName |
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84 | * @param int|null $orgid |
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85 | * |
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86 | * @return Contact |
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87 | */ |
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88 | public function findOrCreateContact($email, $firstName, $lastName, $orgid = null) |
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98 | |||
99 | /** |
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100 | * Updates a contact. |
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101 | * |
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102 | * @param Contact|int|string $id |
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103 | * @param string|null $email |
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104 | * @param string|null $firstName |
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105 | * @param string|null $lastName |
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106 | * @param null $orgid |
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107 | * |
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108 | * @return Contact|null |
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109 | */ |
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110 | public function updateContact($id, $email, $firstName, $lastName, $orgid = null) |
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118 | |||
119 | /** |
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120 | * Deletes a contact. |
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121 | * |
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122 | * @param Contact|int|string $contact |
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123 | */ |
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124 | public function deleteContact($contact) |
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128 | |||
129 | /** |
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130 | * Get all automations of a contact. |
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131 | * |
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132 | * @param \TestMonitor\ActiveCampaign\Resources\Contact $contact |
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133 | * |
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134 | * @return array |
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135 | */ |
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136 | public function contactAutomations(Contact $contact) |
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144 | |||
145 | /** |
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146 | * Get all tags of a contact. |
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147 | * |
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148 | * @param \TestMonitor\ActiveCampaign\Resources\Contact $contact |
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149 | * |
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150 | * @return array |
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151 | */ |
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152 | public function contactTags(Contact $contact) |
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160 | |||
161 | /** |
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162 | * Removing a automation from a contact. |
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163 | * |
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164 | * @param \TestMonitor\ActiveCampaign\Resources\Contact $contact |
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165 | * @param \TestMonitor\ActiveCampaign\Resources\Automation $automation |
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166 | */ |
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167 | View Code Duplication | public function removeAutomationFromContact(Contact $contact, Automation $automation) |
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181 | |||
182 | /** |
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183 | * Removing all automations from a contact. |
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184 | * |
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185 | * @param \TestMonitor\ActiveCampaign\Resources\Contact $contact |
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186 | */ |
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187 | public function removeAllAutomationsFromContact(Contact $contact) |
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195 | |||
196 | /** |
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197 | * Removing a tag from a contact. |
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198 | * |
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199 | * @param \TestMonitor\ActiveCampaign\Resources\Contact $contact |
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200 | * @param \TestMonitor\ActiveCampaign\Resources\Tag $tag |
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201 | */ |
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202 | View Code Duplication | public function removeTagFromContact(Contact $contact, Tag $tag) |
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216 | |||
217 | /** |
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218 | * Determines the contact ID. |
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219 | * |
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220 | * @param Contact|int|string $contact |
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221 | */ |
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222 | protected function getContactId($contact) |
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234 | } |
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235 |
This check looks for methods that are used by a trait but not required by it.
To illustrate, let’s look at the following code example
The trait
Idable
provides a methodequalsId
that in turn relies on the methodgetId()
. If this method does not exist on a class mixing in this trait, the method will fail.Adding the
getId()
as an abstract method to the trait will make sure it is available.