Add meta boxes for custom taxonomies in order edit screens

plugins/woocommerce/changelog/fix-38560

@@ -0,0 +1,4 @@
+Significance: patch
+Type: fix
+
+Add support for taxonomy meta boxes in HPOS order edit screen.

plugins/woocommerce/src/Internal/Admin/Orders/Edit.php

@@ -6,6 +6,7 @@
 namespace Automattic\WooCommerce\Internal\Admin\Orders;
 
 use Automattic\WooCommerce\Internal\Admin\Orders\MetaBoxes\CustomMetaBox;
+use Automattic\WooCommerce\Internal\Admin\Orders\MetaBoxes\TaxonomiesMetaBox;
 
 /**
  * Class Edit.
@@ -26,6 +27,13 @@ class Edit {
 	 */
 	private $custom_meta_box;
 
+	/**
+	 * Instance of the TaxonomiesMetaBox class. Used to render meta box for taxonomies.
+	 *
+	 * @var TaxonomiesMetaBox
+	 */
+	private $taxonomies_meta_box;
+
 	/**
 	 * Instance of WC_Order to be used in metaboxes.
 	 *
@@ -110,10 +118,16 @@ public function setup( \WC_Order $order ) {
 		if ( ! isset( $this->custom_meta_box ) ) {
 			$this->custom_meta_box = wc_get_container()->get( CustomMetaBox::class );
 		}
+
+		if ( ! isset( $this->taxonomies_meta_box ) ) {
+			$this->taxonomies_meta_box = wc_get_container()->get( TaxonomiesMetaBox::class );
+		}
+
 		$this->add_save_meta_boxes();
 		$this->handle_order_update();
 		$this->add_order_meta_boxes( $this->screen_id, __( 'Order', 'woocommerce' ) );
 		$this->add_order_specific_meta_box();
+		$this->add_order_taxonomies_meta_box();
 
 		/**
 		 * From wp-admin/includes/meta-boxes.php.
@@ -159,6 +173,15 @@ private function add_order_specific_meta_box() {
 		);
 	}
 
+	/**
+	 * Render custom meta box.
+	 *
+	 * @return void
+	 */
+	private function add_order_taxonomies_meta_box() {
+		$this->taxonomies_meta_box->add_taxonomies_meta_boxes( $this->screen_id, $this->order->get_type() );
+	}
+
 	/**
 	 * Takes care of updating order data. Fires action that metaboxes can hook to for order data updating.
 	 *
@@ -176,6 +199,10 @@ public function handle_order_update() {
 
 		check_admin_referer( $this->get_order_edit_nonce_action() );
 
+		// phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- sanitized later on by taxonomies_meta_box object.
+		$taxonomy_input = isset( $_POST['tax_input'] ) ? wp_unslash( $_POST['tax_input'] ) : null;
+		$this->taxonomies_meta_box->save_taxonomies( $this->order, $taxonomy_input );
+
 		/**
 		 * Save meta for shop order.
 		 *

plugins/woocommerce/src/Internal/Admin/Orders/MetaBoxes/TaxonomiesMetaBox.php

@@ -0,0 +1,147 @@
+<?php
+
+namespace Automattic\WooCommerce\Internal\Admin\Orders\MetaBoxes;
+
+use Automattic\WooCommerce\Internal\DataStores\Orders\OrdersTableDataStore;
+
+/**
+ * TaxonomiesMetaBox class, renders taxonomy sidebar widget on order edit screen.
+ */
+class TaxonomiesMetaBox {
+
+	/**
+	 * Order Table data store class.
+	 *
+	 * @var OrdersTableDataStore
+	 */
+	private $orders_table_data_store;
+
+	/**
+	 * Dependency injection init method.
+	 *
+	 * @param OrdersTableDataStore $orders_table_data_store Order Table data store class.
+	 *
+	 * @return void
+	 */
+	public function init( OrdersTableDataStore $orders_table_data_store ) {
+		$this->orders_table_data_store = $orders_table_data_store;
+	}
+
+	/**
+	 * Registers meta boxes to be rendered in order edit screen for taxonomies.
+	 *
+	 * Note: This is re-implementation of part of WP core's `register_and_do_post_meta_boxes` function. Since the code block that add meta box for taxonomies is not filterable, we have to re-implement it.
+	 *
+	 * @param string $screen_id Screen ID.
+	 * @param string $order_type Order type to register meta boxes for.
+	 *
+	 * @return void
+	 */
+	public function add_taxonomies_meta_boxes( string $screen_id, string $order_type ) {
+		include_once ABSPATH . 'wp-admin/includes/meta-boxes.php';
+		$taxonomies = get_object_taxonomies( $order_type );
+		// All taxonomies.
+		foreach ( $taxonomies as $tax_name ) {
+			$taxonomy = get_taxonomy( $tax_name );
+			if ( ! $taxonomy->show_ui || false === $taxonomy->meta_box_cb ) {
+				continue;
+			}
+
+			if ( 'post_categories_meta_box' === $taxonomy->meta_box_cb ) {
+				$taxonomy->meta_box_cb = array( $this, 'order_categories_meta_box' );
+			}
+
+			if ( 'post_tags_meta_box' === $taxonomy->meta_box_cb ) {
+				$taxonomy->meta_box_cb = array( $this, 'order_tags_meta_box' );
+			}
+
+			$label = $taxonomy->labels->name;
+
+			if ( ! is_taxonomy_hierarchical( $tax_name ) ) {
+				$tax_meta_box_id = 'tagsdiv-' . $tax_name;
+			} else {
+				$tax_meta_box_id = $tax_name . 'div';
+			}
+
+			add_meta_box(
+				$tax_meta_box_id,
+				$label,
+				$taxonomy->meta_box_cb,
+				$screen_id,
+				'side',
+				'core',
+				array(
+					'taxonomy'               => $tax_name,
+					'__back_compat_meta_box' => true,
+				)
+			);
+		}
+	}
+
+	/**
+	 * Save handler for taxonomy data.
+	 *
+	 * @param \WC_Abstract_Order $order Order object.
+	 * @param array|null         $taxonomy_input Taxonomy input passed from input.
+	 */
+	public function save_taxonomies( \WC_Abstract_Order $order, $taxonomy_input ) {
+		if ( ! isset( $taxonomy_input ) ) {
+			return;
+		}
+
+		$sanitized_tax_input = $this->sanitize_tax_input( $taxonomy_input );
+
+		$sanitized_tax_input = $this->orders_table_data_store->init_default_taxonomies( $order, $sanitized_tax_input );
+		$this->orders_table_data_store->set_custom_taxonomies( $order, $sanitized_tax_input );
+	}
+
+	/**
+	 * Sanitize taxonomy input by calling sanitize callbacks for each registered taxonomy.
+	 *
+	 * @param array|null $taxonomy_data Nonce verified taxonomy input.
+	 *
+	 * @return array Sanitized taxonomy input.
+	 */
+	private function sanitize_tax_input( $taxonomy_data ) : array {
+		$sanitized_tax_input = array();
+		if ( ! is_array( $taxonomy_data ) ) {
+			return $sanitized_tax_input;
+		}
+
+		// Convert taxonomy input to term IDs, to avoid ambiguity.
+		foreach ( $taxonomy_data as $taxonomy => $terms ) {
+			$tax_object = get_taxonomy( $taxonomy );
+			if ( $tax_object && isset( $tax_object->meta_box_sanitize_cb ) ) {
+				$sanitized_tax_input[ $taxonomy ] = call_user_func_array( $tax_object->meta_box_sanitize_cb, array( $taxonomy, $terms ) );
+			}
+		}
+
+		return $sanitized_tax_input;
+	}
+
+	/**
+	 * Add the categories meta box to the order screen. This is just a wrapper around the post_categories_meta_box.
+	 *
+	 * @param \WC_Abstract_Order $order Order object.
+	 * @param array              $box   Meta box args.
+	 *
+	 * @return void
+	 */
+	public function order_categories_meta_box( $order, $box ) {
+		$post = get_post( $order->get_id() );
+		post_categories_meta_box( $post, $box );
+	}
+
+	/**
+	 * Add the tags meta box to the order screen. This is just a wrapper around the post_tags_meta_box.
+	 *
+	 * @param \WC_Abstract_Order $order Order object.
+	 * @param array              $box   Meta box args.
+	 *
+	 * @return void
+	 */
+	public function order_tags_meta_box( $order, $box ) {
+		$post = get_post( $order->get_id() );
+		post_tags_meta_box( $post, $box );
+	}
+}

plugins/woocommerce/src/Internal/DataStores/Orders/OrdersTableDataStore.php

@@ -1641,6 +1641,84 @@ protected function persist_order_to_db( &$order, bool $force_all_fields = false
 
 		$changes = $order->get_changes();
 		$this->update_address_index_meta( $order, $changes );
+		$default_taxonomies = $this->init_default_taxonomies( $order, array() );
+		$this->set_custom_taxonomies( $order, $default_taxonomies );
+	}
+
+	/**
+	 * Set default taxonomies for the order.
+	 *
+	 * Note: This is re-implementation of part of WP core's `wp_insert_post` function. Since the code block that set default taxonomies is not filterable, we have to re-implement it.
+	 *
+	 * @param \WC_Abstract_Order $order               Order object.
+	 * @param array              $sanitized_tax_input Sanitized taxonomy input.
+	 *
+	 * @return array Sanitized tax input with default taxonomies.
+	 */
+	public function init_default_taxonomies( \WC_Abstract_Order $order, array $sanitized_tax_input ) {
+		if ( 'auto-draft' === $order->get_status() ) {
+			return $sanitized_tax_input;
+		}
+
+		foreach ( get_object_taxonomies( $order->get_type(), 'object' ) as $taxonomy => $tax_object ) {
+			if ( empty( $tax_object->default_term ) ) {
+				return $sanitized_tax_input;
+			}
+
+			// Filter out empty terms.
+			if ( isset( $sanitized_tax_input[ $taxonomy ] ) && is_array( $sanitized_tax_input[ $taxonomy ] ) ) {
+				$sanitized_tax_input[ $taxonomy ] = array_filter( $sanitized_tax_input[ $taxonomy ] );
+			}
+
+			// Passed custom taxonomy list overwrites the existing list if not empty.
+			$terms = wp_get_object_terms( $order->get_id(), $taxonomy, array( 'fields' => 'ids' ) );
+			if ( ! empty( $terms ) && empty( $sanitized_tax_input[ $taxonomy ] ) ) {
+				$sanitized_tax_input[ $taxonomy ] = $terms;
+			}
+
+			if ( empty( $sanitized_tax_input[ $taxonomy ] ) ) {
+				$default_term_id = get_option( 'default_term_' . $taxonomy );
+				if ( ! empty( $default_term_id ) ) {
+					$sanitized_tax_input[ $taxonomy ] = array( (int) $default_term_id );
+				}
+			}
+		}
+		return $sanitized_tax_input;
+	}
+
+	/**
+	 * Set custom taxonomies for the order.
+	 *
+	 * Note: This is re-implementation of part of WP core's `wp_insert_post` function. Since the code block that set custom taxonomies is not filterable, we have to re-implement it.
+	 *
+	 * @param \WC_Abstract_Order $order               Order object.
+	 * @param array              $sanitized_tax_input Sanitized taxonomy input.
+	 *
+	 * @return void
+	 */
+	public function set_custom_taxonomies( \WC_Abstract_Order $order, array $sanitized_tax_input ) {
+		if ( empty( $sanitized_tax_input ) ) {
+			return;
+		}
+
+		foreach ( $sanitized_tax_input as $taxonomy => $tags ) {
+			$taxonomy_obj = get_taxonomy( $taxonomy );
+
+			if ( ! $taxonomy_obj ) {
+				/* translators: %s: Taxonomy name. */
+				_doing_it_wrong( __FUNCTION__, esc_html( sprintf( __( 'Invalid taxonomy: %s.', 'woocommerce' ), $taxonomy ) ), '7.9.0' );
+				continue;
+			}
+
+			// array = hierarchical, string = non-hierarchical.
+			if ( is_array( $tags ) ) {
+				$tags = array_filter( $tags );
+			}
+
+			if ( current_user_can( $taxonomy_obj->cap->assign_terms ) ) {
+				wp_set_post_terms( $order->get_id(), $tags, $taxonomy );
+			}
+		}
 	}
 
 	/**

plugins/woocommerce/src/Internal/DependencyManagement/ServiceProviders/OrderAdminServiceProvider.php

@@ -9,7 +9,9 @@
 use Automattic\WooCommerce\Internal\Admin\Orders\Edit;
 use Automattic\WooCommerce\Internal\Admin\Orders\EditLock;
 use Automattic\WooCommerce\Internal\Admin\Orders\ListTable;
+use Automattic\WooCommerce\Internal\Admin\Orders\MetaBoxes\TaxonomiesMetaBox;
 use Automattic\WooCommerce\Internal\Admin\Orders\PageController;
+use Automattic\WooCommerce\Internal\DataStores\Orders\OrdersTableDataStore;
 use Automattic\WooCommerce\Internal\DependencyManagement\AbstractServiceProvider;
 
 /**
@@ -28,6 +30,7 @@ class OrderAdminServiceProvider extends AbstractServiceProvider {
 		Edit::class,
 		ListTable::class,
 		EditLock::class,
+		TaxonomiesMetaBox::class,
 	);
 
 	/**
@@ -41,5 +44,6 @@ public function register() {
 		$this->share( Edit::class )->addArgument( PageController::class );
 		$this->share( ListTable::class )->addArgument( PageController::class );
 		$this->share( EditLock::class );
+		$this->share( TaxonomiesMetaBox::class )->addArgument( OrdersTableDataStore::class );
 	}
 }

plugins/woocommerce/tests/php/includes/abstracts/class-wc-abstract-order-test.php

@@ -190,7 +190,7 @@ public function set_props( $args, $context = 'set' ) {
 	 */
 	public function test_apply_coupon_across_status() {
 		$coupon_code = 'coupon_test_count_across_status';
-		$coupon = WC_Helper_Coupon::create_coupon( $coupon_code );
+		$coupon      = WC_Helper_Coupon::create_coupon( $coupon_code );
 		$this->assertEquals( 0, $coupon->get_usage_count() );
 
 		$order = WC_Helper_Order::create_order();
@@ -253,8 +253,8 @@ public function test_apply_coupon_multiple_across_status() {
 	 */
 	public function test_apply_coupon_stores_meta_data() {
 		$coupon_code = 'coupon_test_meta_data';
-		$coupon = WC_Helper_Coupon::create_coupon( $coupon_code );
-		$order  = WC_Helper_Order::create_order();
+		$coupon      = WC_Helper_Coupon::create_coupon( $coupon_code );
+		$order       = WC_Helper_Order::create_order();
 		$order->set_status( 'processing' );
 		$order->save();
 		$order->apply_coupon( $coupon_code );
@@ -324,4 +324,29 @@ function( $order_id ) {
 		$order = wc_get_order( $order->get_id() );
 		$this->assertInstanceOf( Automattic\WooCommerce\Admin\Overrides\Order::class, $order );
 	}
+
+	/**
+	 * @testDox When a taxonomy with a default term is set on the order, it's inserted when a new order is created.
+	 */
+	public function test_default_term_for_custom_taxonomy() {
+		$custom_taxonomy = register_taxonomy(
+			'custom_taxonomy',
+			'shop_order',
+			array(
+				'default_term' => 'new_term',
+			),
+		);
+
+		// Set user who has access to create term.
+		$current_user_id = get_current_user_id();
+		$user            = new WP_User( wp_create_user( 'test', '' ) );
+		$user->set_role( 'administrator' );
+		wp_set_current_user( $user->ID );
+
+		$order = wc_create_order();
+
+		wp_set_current_user( $current_user_id );
+		$order_terms = wp_list_pluck( wp_get_object_terms( $order->get_id(), $custom_taxonomy->name ), 'name' );
+		$this->assertContains( 'new_term', $order_terms );
+	}
 }