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:
Complex classes like Functions often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Functions, and based on these observations, apply Extract Interface, too.
1 | <?php |
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15 | class Functions { |
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16 | const HTTPS_CHECK_OPTION_PREFIX = 'jetpack_sync_https_history_'; |
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17 | const HTTPS_CHECK_HISTORY = 5; |
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18 | |||
19 | /** |
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20 | * Return array of Jetpack modules. |
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21 | * |
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22 | * @return array |
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23 | */ |
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24 | public static function get_modules() { |
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29 | |||
30 | /** |
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31 | * Return array of taxonomies registered on the site. |
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32 | * |
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33 | * @return array |
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34 | */ |
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35 | public static function get_taxonomies() { |
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46 | |||
47 | /** |
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48 | * Return array of registered shortcodes. |
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49 | * |
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50 | * @return array |
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51 | */ |
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52 | public static function get_shortcodes() { |
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56 | |||
57 | /** |
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58 | * Removes any callback data since we will not be able to process it on our side anyways. |
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59 | * |
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60 | * @param \WP_Taxonomy $taxonomy \WP_Taxonomy item. |
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61 | * |
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62 | * @return mixed|null |
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63 | */ |
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64 | public static function sanitize_taxonomy( $taxonomy ) { |
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90 | |||
91 | /** |
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92 | * Return array of registered post types. |
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93 | * |
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94 | * @return array |
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95 | */ |
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96 | public static function get_post_types() { |
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108 | |||
109 | /** |
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110 | * Sanitizes by cloning post type object. |
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111 | * |
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112 | * @param object $post_type \WP_Post_Type. |
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113 | * |
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114 | * @return object |
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115 | */ |
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116 | public static function sanitize_post_type( $post_type ) { |
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126 | |||
127 | /** |
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128 | * Return information about a synced post type. |
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129 | * |
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130 | * @param array $sanitized_post_type Array of args used in constructing \WP_Post_Type. |
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131 | * @param string $post_type Post type name. |
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132 | * |
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133 | * @return object \WP_Post_Type |
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134 | */ |
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135 | public static function expand_synced_post_type( $sanitized_post_type, $post_type ) { |
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144 | |||
145 | /** |
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146 | * Returns site's post_type_features. |
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147 | * |
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148 | * @return array |
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149 | */ |
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150 | public static function get_post_type_features() { |
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155 | |||
156 | /** |
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157 | * Return hosting provider. |
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158 | * |
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159 | * Uses a set of known constants, classes, or functions to help determine the hosting platform. |
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160 | * |
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161 | * @return string Hosting provider. |
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162 | */ |
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163 | public static function get_hosting_provider() { |
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190 | |||
191 | /** |
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192 | * Return array of allowed REST API post types. |
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193 | * |
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194 | * @return array Array of allowed post types. |
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195 | */ |
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196 | public static function rest_api_allowed_post_types() { |
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200 | |||
201 | /** |
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202 | * Return array of allowed REST API public metadata. |
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203 | * |
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204 | * @return array Array of allowed metadata. |
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205 | */ |
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206 | public static function rest_api_allowed_public_metadata() { |
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210 | |||
211 | /** |
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212 | * Finds out if a site is using a version control system. |
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213 | * |
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214 | * @return bool |
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215 | **/ |
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216 | public static function is_version_controlled() { |
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225 | |||
226 | /** |
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227 | * Returns true if the site has file write access false otherwise. |
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228 | * |
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229 | * @return bool |
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230 | **/ |
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231 | public static function file_system_write_access() { |
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257 | |||
258 | /** |
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259 | * Helper function that is used when getting home or siteurl values. Decides |
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260 | * whether to get the raw or filtered value. |
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261 | * |
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262 | * @param string $url_type URL to get, home or siteurl. |
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263 | * @return string |
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264 | */ |
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265 | public static function get_raw_or_filtered_url( $url_type ) { |
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283 | |||
284 | /** |
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285 | * Return the escaped home_url. |
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286 | * |
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287 | * @return string |
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288 | */ |
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289 | public static function home_url() { |
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301 | |||
302 | /** |
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303 | * Return the escaped siteurl. |
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304 | * |
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305 | * @return string |
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306 | */ |
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307 | public static function site_url() { |
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319 | |||
320 | /** |
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321 | * Return main site URL with a normalized protocol. |
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322 | * |
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323 | * @return string |
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324 | */ |
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325 | public static function main_network_site_url() { |
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328 | |||
329 | /** |
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330 | * Return URL with a normalized protocol. |
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331 | * |
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332 | * @param callable $callable Function to retrieve URL option. |
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333 | * @param string $new_value URL Protocol to set URLs to. |
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334 | * @return string Normalized URL. |
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335 | */ |
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336 | public static function get_protocol_normalized_url( $callable, $new_value ) { |
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360 | |||
361 | /** |
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362 | * Return URL from option or PHP constant. |
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363 | * |
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364 | * @param string $option_name (e.g. 'home'). |
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365 | * |
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366 | * @return mixed|null URL. |
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367 | */ |
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368 | public static function get_raw_url( $option_name ) { |
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386 | |||
387 | /** |
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388 | * Normalize domains by removing www unless declared in the site's option. |
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389 | * |
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390 | * @param string $option Option value from the site. |
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391 | * @param callable $url_function Function retrieving the URL to normalize. |
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392 | * @return mixed|string URL. |
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393 | */ |
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394 | public static function normalize_www_in_url( $option, $url_function ) { |
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422 | |||
423 | /** |
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424 | * Return filtered value of get_plugins. |
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425 | * |
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426 | * @return mixed|void |
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427 | */ |
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428 | public static function get_plugins() { |
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436 | |||
437 | /** |
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438 | * Get custom action link tags that the plugin is using |
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439 | * Ref: https://codex.wordpress.org/Plugin_API/Filter_Reference/plugin_action_links_(plugin_file_name) |
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440 | * |
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441 | * @param string $plugin_file_singular Particular plugin. |
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442 | * @return array of plugin action links (key: link name value: url) |
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443 | */ |
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444 | public static function get_plugins_action_links( $plugin_file_singular = null ) { |
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458 | |||
459 | /** |
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460 | * Return the WP version as defined in the $wp_version global. |
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461 | * |
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462 | * @return string |
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463 | */ |
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464 | public static function wp_version() { |
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468 | |||
469 | /** |
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470 | * Return site icon url used on the site. |
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471 | * |
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472 | * @param int $size Size of requested icon in pixels. |
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473 | * @return mixed|string|void |
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474 | */ |
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475 | public static function site_icon_url( $size = 512 ) { |
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479 | |||
480 | /** |
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481 | * Return roles registered on the site. |
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482 | * |
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483 | * @return array |
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484 | */ |
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485 | public static function roles() { |
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489 | |||
490 | /** |
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491 | * Determine time zone from WordPress' options "timezone_string" |
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492 | * and "gmt_offset". |
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493 | * |
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494 | * 1. Check if `timezone_string` is set and return it. |
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495 | * 2. Check if `gmt_offset` is set, formats UTC-offset from it and return it. |
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496 | * 3. Default to "UTC+0" if nothing is set. |
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497 | * |
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498 | * Note: This function is specifically not using wp_timezone() to keep consistency with |
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499 | * the existing formatting of the timezone string. |
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500 | * |
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501 | * @return string |
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502 | */ |
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503 | public static function get_timezone() { |
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523 | |||
524 | /** |
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525 | * Return list of paused themes. |
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526 | * |
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527 | * @todo Remove function_exists check when WP 5.2 is the minimum. |
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528 | * |
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529 | * @return array|bool Array of paused themes or false if unsupported. |
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530 | */ |
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531 | public static function get_paused_themes() { |
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538 | |||
539 | /** |
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540 | * Return list of paused plugins. |
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541 | * |
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542 | * @todo Remove function_exists check when WP 5.2 is the minimum. |
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543 | * |
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544 | * @return array|bool Array of paused plugins or false if unsupported. |
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545 | */ |
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546 | public static function get_paused_plugins() { |
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553 | } |
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554 |
This check looks for variable assignements that are either overwritten by other assignments or where the variable is not used subsequently.
Both the
$myVar
assignment in line 1 and the$higher
assignment in line 2 are dead. The first because$myVar
is never used and the second because$higher
is always overwritten for every possible time line.