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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| 15 | class Constants extends Module { |
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| 16 | /** |
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| 17 | * Name of the constants checksum option. |
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| 18 | * |
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| 19 | * @var string |
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| 20 | */ |
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| 21 | const CONSTANTS_CHECKSUM_OPTION_NAME = 'jetpack_constants_sync_checksum'; |
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| 22 | |||
| 23 | /** |
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| 24 | * Name of the transient for locking constants. |
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| 25 | * |
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| 26 | * @var string |
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| 27 | */ |
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| 28 | const CONSTANTS_AWAIT_TRANSIENT_NAME = 'jetpack_sync_constants_await'; |
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| 29 | |||
| 30 | /** |
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| 31 | * Sync module name. |
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| 32 | * |
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| 33 | * @access public |
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| 34 | * |
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| 35 | * @return string |
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| 36 | */ |
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| 37 | public function name() { |
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| 40 | |||
| 41 | /** |
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| 42 | * Initialize constants action listeners. |
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| 43 | * |
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| 44 | * @access public |
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| 45 | * |
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| 46 | * @param callable $callable Action handler callable. |
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| 47 | */ |
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| 48 | public function init_listeners( $callable ) { |
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| 51 | |||
| 52 | /** |
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| 53 | * Initialize constants action listeners for full sync. |
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| 54 | * |
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| 55 | * @access public |
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| 56 | * |
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| 57 | * @param callable $callable Action handler callable. |
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| 58 | */ |
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| 59 | public function init_full_sync_listeners( $callable ) { |
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| 62 | |||
| 63 | /** |
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| 64 | * Initialize the module in the sender. |
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| 65 | * |
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| 66 | * @access public |
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| 67 | */ |
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| 68 | public function init_before_send() { |
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| 74 | |||
| 75 | /** |
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| 76 | * Perform module cleanup. |
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| 77 | * Deletes any transients and options that this module uses. |
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| 78 | * Usually triggered when uninstalling the plugin. |
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| 79 | * |
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| 80 | * @access public |
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| 81 | */ |
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| 82 | public function reset_data() { |
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| 86 | |||
| 87 | /** |
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| 88 | * Set the constants whitelist. |
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| 89 | * |
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| 90 | * @access public |
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| 91 | * @todo We don't seem to use this one. Should we remove it? |
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| 92 | * |
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| 93 | * @param array $constants The new constants whitelist. |
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| 94 | */ |
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| 95 | public function set_constants_whitelist( $constants ) { |
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| 98 | |||
| 99 | /** |
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| 100 | * Get the constants whitelist. |
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| 101 | * |
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| 102 | * @access public |
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| 103 | * |
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| 104 | * @return array The constants whitelist. |
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| 105 | */ |
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| 106 | public function get_constants_whitelist() { |
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| 109 | |||
| 110 | /** |
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| 111 | * Enqueue the constants actions for full sync. |
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| 112 | * |
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| 113 | * @access public |
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| 114 | * |
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| 115 | * @param array $config Full sync configuration for this sync module. |
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| 116 | * @param int $max_items_to_enqueue Maximum number of items to enqueue. |
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| 117 | * @param boolean $state True if full sync has finished enqueueing this module, false otherwise. |
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| 118 | * |
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| 119 | * @return array Number of actions enqueued, and next module state. |
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| 120 | */ |
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| 121 | public function enqueue_full_sync_actions( $config, $max_items_to_enqueue, $state ) { // phpcs:ignore VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable |
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| 134 | |||
| 135 | /** |
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| 136 | * Send the constants actions for full sync. |
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| 137 | * |
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| 138 | * @access public |
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| 139 | * |
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| 140 | * @param array $config Full sync configuration for this sync module. |
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| 141 | * @param int $send_until The timestamp until the current request can send. |
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| 142 | * @param array $state This module Full Sync status. |
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| 143 | * |
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| 144 | * @return array This module Full Sync status. |
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| 145 | */ |
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| 146 | public function send_full_sync_actions( $config, $send_until, $state ) { // phpcs:ignore VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable |
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| 153 | |||
| 154 | /** |
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| 155 | * Retrieve an estimated number of actions that will be enqueued. |
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| 156 | * |
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| 157 | * @access public |
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| 158 | * |
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| 159 | * @param array $config Full sync configuration for this sync module. |
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| 160 | * |
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| 161 | * @return array Number of items yet to be enqueued. |
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| 162 | */ |
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| 163 | public function estimate_full_sync_actions( $config ) { // phpcs:ignore VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable |
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| 166 | |||
| 167 | /** |
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| 168 | * Retrieve the actions that will be sent for this module during a full sync. |
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| 169 | * |
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| 170 | * @access public |
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| 171 | * |
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| 172 | * @return array Full sync actions of this module. |
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| 173 | */ |
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| 174 | public function get_full_sync_actions() { |
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| 177 | |||
| 178 | /** |
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| 179 | * Sync the constants if we're supposed to. |
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| 180 | * |
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| 181 | * @access public |
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| 182 | */ |
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| 183 | public function maybe_sync_constants() { |
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| 217 | |||
| 218 | /** |
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| 219 | * Retrieve all constants as per the current constants whitelist. |
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| 220 | * Public so that we don't have to store an option for each constant. |
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| 221 | * |
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| 222 | * @access public |
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| 223 | * |
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| 224 | * @return array All constants. |
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| 225 | */ |
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| 226 | public function get_all_constants() { |
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| 234 | |||
| 235 | /** |
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| 236 | * Retrieve the value of a constant. |
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| 237 | * Used as a wrapper to standartize access to constants. |
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| 238 | * |
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| 239 | * @access private |
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| 240 | * |
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| 241 | * @param string $constant Constant name. |
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| 242 | * |
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| 243 | * @return mixed Return value of the constant. |
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| 244 | */ |
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| 245 | private function get_constant( $constant ) { |
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| 250 | |||
| 251 | /** |
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| 252 | * Expand the constants within a hook before they are serialized and sent to the server. |
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| 253 | * |
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| 254 | * @access public |
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| 255 | * |
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| 256 | * @param array $args The hook parameters. |
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| 257 | * |
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| 258 | * @return array $args The hook parameters. |
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| 259 | */ |
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| 260 | public function expand_constants( $args ) { |
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| 274 | |||
| 275 | /** |
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| 276 | * Return Total number of objects. |
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| 277 | * |
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| 278 | * @param array $config Full Sync config. |
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| 279 | * |
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| 280 | * @return int total |
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| 281 | */ |
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| 282 | public function total( $config ) { // phpcs:ignore VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable |
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| 285 | |||
| 286 | /** |
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| 287 | * Retrieve a set of constants by their IDs. |
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| 288 | * |
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| 289 | * @access public |
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| 290 | * |
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| 291 | * @param string $object_type Object type. |
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| 292 | * @param array $ids Object IDs. |
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| 293 | * @return array Array of objects. |
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| 294 | */ |
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| 295 | public function get_objects_by_id( $object_type, $ids ) { |
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| 313 | |||
| 314 | /** |
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| 315 | * Retrieve a constant by its name. |
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| 316 | * |
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| 317 | * @access public |
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| 318 | * |
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| 319 | * @param string $object_type Type of the sync object. |
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| 320 | * @param string $id ID of the sync object. |
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| 321 | * @return mixed Value of Constant. |
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| 322 | */ |
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| 323 | public function get_object_by_id( $object_type, $id ) { |
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| 336 | |||
| 337 | } |
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| 338 |
In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code:
Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: