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 Jetpack_WooCommerce_Analytics_Universal 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 Jetpack_WooCommerce_Analytics_Universal, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 20 | class Jetpack_WooCommerce_Analytics_Universal { |
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| 21 | /** |
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| 22 | * Jetpack_WooCommerce_Analytics_Universal constructor. |
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| 23 | */ |
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| 24 | public function __construct() { |
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| 25 | // loading _wca |
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| 26 | add_action( 'wp_head', array( $this, 'wp_head_top' ), 1 ); |
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| 27 | |||
| 28 | // add to carts from non-product pages or lists (search, store etc.) |
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| 29 | add_action( 'wp_head', array( $this, 'loop_session_events' ), 2 ); |
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| 30 | |||
| 31 | // loading s.js |
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| 32 | add_action( 'wp_head', array( $this, 'wp_head_bottom' ), 999999 ); |
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| 33 | |||
| 34 | // Capture cart events |
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| 35 | add_action( 'woocommerce_add_to_cart', array( $this, 'capture_add_to_cart' ), 10, 6 ); |
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| 36 | |||
| 37 | // single product page view |
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| 38 | add_action( 'woocommerce_after_single_product', array( $this, 'capture_product_view' ) ); |
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| 39 | |||
| 40 | add_action( 'woocommerce_after_cart', array( $this, 'remove_from_cart' ) ); |
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| 41 | add_action( 'woocommerce_after_mini_cart', array( $this, 'remove_from_cart' ) ); |
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| 42 | add_action( 'wcct_before_cart_widget', array( $this, 'remove_from_cart' ) ); |
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| 43 | add_filter( 'woocommerce_cart_item_remove_link', array( $this, 'remove_from_cart_attributes' ), 10, 2 ); |
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| 44 | |||
| 45 | // cart checkout |
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| 46 | add_action( 'woocommerce_after_checkout_form', array( $this, 'checkout_process' ) ); |
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| 47 | |||
| 48 | // order confirmed |
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| 49 | add_action( 'woocommerce_thankyou', array( $this, 'order_process' ), 10, 1 ); |
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| 50 | add_action( 'woocommerce_after_cart', array( $this, 'remove_from_cart_via_quantity' ), 10, 1 ); |
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| 51 | } |
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| 52 | |||
| 53 | /** |
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| 54 | * Make _wca available to queue events |
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| 55 | */ |
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| 56 | public function wp_head_top() { |
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| 57 | if ( is_cart() || is_checkout() || is_checkout_pay_page() || is_order_received_page() || is_add_payment_method_page() ) { |
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| 58 | $prevent_referrer_code = "<script>window._wca_prevent_referrer = true;</script>"; |
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| 59 | echo "$prevent_referrer_code\r\n"; |
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| 60 | } |
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| 61 | $wca_code = "<script>window._wca = window._wca || [];</script>"; |
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| 62 | echo "$wca_code\r\n"; |
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| 63 | } |
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| 64 | |||
| 65 | |||
| 66 | /** |
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| 67 | * Place script to call s.js, Store Analytics |
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| 68 | */ |
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| 69 | public function wp_head_bottom() { |
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| 74 | |||
| 75 | /** |
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| 76 | * On product lists or other non-product pages, add an event listener to "Add to Cart" button click |
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| 77 | */ |
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| 78 | public function loop_session_events() { |
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| 107 | |||
| 108 | /** |
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| 109 | * On the cart page, add an event listener for removal of product click |
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| 110 | */ |
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| 111 | View Code Duplication | public function remove_from_cart() { |
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| 135 | |||
| 136 | /** |
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| 137 | * Adds the product ID to the remove product link (for use by remove_from_cart above) if not present |
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| 138 | * |
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| 139 | * @param string $url url. |
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| 140 | * @param string $key key. |
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| 141 | * @return mixed. |
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| 142 | */ |
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| 143 | View Code Duplication | public function remove_from_cart_attributes( $url, $key ) { |
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| 144 | if ( false !== strpos( $url, 'data-product_id' ) ) { |
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| 145 | return $url; |
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| 146 | } |
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| 147 | |||
| 148 | $item = WC()->cart->get_cart_item( $key ); |
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| 149 | $product = $item['data']; |
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| 150 | |||
| 151 | $new_attributes = sprintf( |
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| 152 | 'href="%s" data-product_id="%s" data-product_sku="%s"', |
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| 153 | esc_attr( $url ), |
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| 154 | esc_attr( $product->get_id() ), |
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| 155 | esc_attr( $product->get_sku() ) |
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| 156 | ); |
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| 157 | $url = str_replace( 'href=', $new_attributes, $url ); |
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| 158 | return $url; |
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| 159 | } |
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| 160 | |||
| 161 | /** |
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| 162 | * Gather relevant product information |
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| 163 | * |
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| 164 | * @param array $product product |
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| 165 | * @return array |
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| 166 | */ |
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| 167 | public function get_product_details( $product ) { |
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| 175 | |||
| 176 | /** |
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| 177 | * Track a product page view |
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| 178 | */ |
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| 179 | public function capture_product_view() { |
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| 197 | |||
| 198 | /** |
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| 199 | * On the Checkout page, trigger an event for each product in the cart |
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| 200 | */ |
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| 201 | public function checkout_process() { |
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| 233 | |||
| 234 | /** |
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| 235 | * After the checkout process, fire an event for each item in the order |
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| 236 | * |
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| 237 | * @param string $order_id Order Id. |
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| 238 | */ |
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| 239 | public function order_process( $order_id ) { |
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| 265 | |||
| 266 | /** |
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| 267 | * Listen for clicks on the "Update Cart" button to know if an item has been removed by |
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| 268 | * updating its quantity to zero |
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| 269 | */ |
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| 270 | View Code Duplication | public function remove_from_cart_via_quantity() { |
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| 291 | |||
| 292 | /** |
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| 293 | * Get the current user id |
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| 294 | * |
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| 295 | * @return int |
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| 296 | */ |
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| 297 | public function get_user_id() { |
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| 305 | |||
| 306 | /** |
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| 307 | * @param $cart_item_key |
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| 308 | * @param $product_id |
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| 309 | * @param $quantity |
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| 310 | * @param $variation_id |
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| 311 | * @param $variation |
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| 312 | * @param $cart_item_data |
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| 313 | */ |
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| 314 | public function capture_add_to_cart( $cart_item_key, $product_id, $quantity, $variation_id, $variation, $cart_item_data ) { |
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| 324 | |||
| 325 | /** |
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| 326 | * @param $product_id |
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| 327 | * @param $quantity |
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| 328 | * @param $event |
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| 329 | */ |
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| 330 | public function capture_event_in_session_data( $product_id, $quantity, $event ) { |
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| 357 | |||
| 358 | /** |
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| 359 | * Gets product categories or varation attributes as a formatted concatenated string |
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| 360 | * |
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| 361 | * @param object $product WC_Product. |
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| 362 | * @return string |
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| 363 | */ |
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| 364 | View Code Duplication | public function get_product_categories_concatenated( $product ) { |
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| 385 | |||
| 386 | } |
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| 387 |
This check looks for improperly formatted assignments.
Every assignment must have exactly one space before and one space after the equals operator.
To illustrate:
will have no issues, while
will report issues in lines 1 and 2.