Fix Historical (deleted) Coupon Reporting (https://github.com/woocommerce/woocommerce-admin/pull/4671)

* Add (failing) test for deleted coupon amounts in reporting.

* Always sync an ID into the order-coupon lookup table.

* Don't remove coupon data from order analytics when the coupon is deleted.

* Fix coupon ID lookup from order item metadata.

* Allow negative coupon_id in the lookup table.

Representing deleted coupons.

* Handle deleted coupons when gathering extended info.

* Add more tests for deleted coupon handling.

* Handle deleted coupons in coupons report table.

* Fix lint errors.

plugins/woocommerce-admin/client/analytics/report/coupons/table.js

@@ -91,25 +91,34 @@ class CouponsReportTable extends Component {
 				discount_type: discountType,
 			} = extendedInfo;
 
-			const couponUrl = getNewPath(
+			const couponUrl =
-				persistedQuery,
+				couponId > 0
-				'/analytics/coupons',
+					? getNewPath( persistedQuery, '/analytics/coupons', {
-				{
 							filter: 'single_coupon',
 							coupons: couponId,
-				}
+					  } )
-			);
+					: null;
-			const couponLink = (
+
+			const couponLink =
+				couponUrl === null ? (
+					code
+				) : (
 					<Link href={ couponUrl } type="wc-admin">
 						{ code }
 					</Link>
 				);
 
-			const ordersUrl = getNewPath( persistedQuery, '/analytics/orders', {
+			const ordersUrl =
+				couponId > 0
+					? getNewPath( persistedQuery, '/analytics/orders', {
 							filter: 'advanced',
 							coupon_includes: couponId,
-			} );
+					  } )
-			const ordersLink = (
+					: null;
+			const ordersLink =
+				ordersUrl === null ? (
+					ordersCount
+				) : (
 					<Link href={ ordersUrl } type="wc-admin">
 						{ formatValue(
 							getCurrencyConfig(),
@@ -133,11 +142,13 @@ class CouponsReportTable extends Component {
 					value: getCurrencyFormatDecimal( amount ),
 				},
 				{
-					display: (
+					display: dateCreated ? (
 						<Date
 							date={ dateCreated }
 							visibleFormat={ dateFormat }
 						/>
+					) : (
+						__( 'N/A', 'woocommerce-admin' )
 					),
 					value: dateCreated,
 				},
@@ -200,7 +211,7 @@ class CouponsReportTable extends Component {
 			fixed_cart: __( 'Fixed cart', 'woocommerce-admin' ),
 			fixed_product: __( 'Fixed product', 'woocommerce-admin' ),
 		};
-		return couponTypes[ discountType ];
+		return couponTypes[ discountType ] || __( 'N/A', 'woocommerce-admin' );
 	}
 
 	render() {

plugins/woocommerce-admin/src/API/Reports/Coupons/DataStore.php

@@ -69,7 +69,6 @@ class DataStore extends ReportsDataStore implements DataStoreInterface {
 	 */
 	public static function init() {
 		add_action( 'woocommerce_analytics_delete_order_stats', array( __CLASS__, 'sync_on_order_delete' ), 5 );
-		add_action( 'delete_post', array( __CLASS__, 'delete_coupon' ) );
 	}
 
 	/**
@@ -165,6 +164,17 @@ class DataStore extends ReportsDataStore implements DataStoreInterface {
 				$coupon_id = $coupon_datum['coupon_id'];
 				$coupon    = new \WC_Coupon( $coupon_id );
 
+				if ( 0 === $coupon->get_id() ) {
+					// Deleted or otherwise invalid coupon.
+					$extended_info = array(
+						'code'             => __( '(Deleted)', 'woocommerce-admin' ),
+						'date_created'     => '',
+						'date_created_gmt' => '',
+						'date_expires'     => '',
+						'date_expires_gmt' => '',
+						'discount_type'    => __( 'N/A', 'woocommerce-admin' ),
+					);
+				} else {
 					$gmt_timzone = new \DateTimeZone( 'UTC' );
 
 					$date_expires = $coupon->get_date_expires();
@@ -198,6 +208,7 @@ class DataStore extends ReportsDataStore implements DataStoreInterface {
 						'discount_type'    => $coupon->get_discount_type(),
 					);
 				}
+			}
 			$coupon_data[ $idx ]['extended_info'] = $extended_info;
 		}
 	}
@@ -314,6 +325,28 @@ class DataStore extends ReportsDataStore implements DataStoreInterface {
 		return $data;
 	}
 
+	/**
+	 * Get coupon ID for an order.
+	 *
+	 * Tries to get the ID from order item meta, then falls back to a query of published coupons.
+	 *
+	 * @param \WC_Order_Item_Coupon $coupon_item The coupon order item object.
+	 * @return int Coupon ID on success, 0 on failure.
+	 */
+	public static function get_coupon_id( \WC_Order_Item_Coupon $coupon_item ) {
+		// First attempt to get coupon ID from order item data.
+		$coupon_data = $coupon_item->get_meta( 'coupon_data', true );
+
+		// Normal checkout orders should have this data.
+		// See: https://github.com/woocommerce/woocommerce/blob/3dc7df7af9f7ca0c0aa34ede74493e856f276abe/includes/abstracts/abstract-wc-order.php#L1206.
+		if ( isset( $coupon_data['id'] ) ) {
+			return $coupon_data['id'];
+		}
+
+		// Try to get the coupon ID using the code.
+		return wc_get_coupon_id_by_code( $coupon_item->get_code() );
+	}
+
 	/**
 	 * Create or update an an entry in the wc_order_coupon_lookup table for an order.
 	 *
@@ -347,14 +380,16 @@ class DataStore extends ReportsDataStore implements DataStoreInterface {
 		$coupon_items       = $order->get_items( 'coupon' );
 		$coupon_items_count = count( $coupon_items );
 		$num_updated        = 0;
+		$num_deleted        = 0;
 
 		foreach ( $coupon_items as $coupon_item ) {
-			$coupon_id = wc_get_coupon_id_by_code( $coupon_item->get_code() );
+			$coupon_id = self::get_coupon_id( $coupon_item );
 			unset( $existing_items[ $coupon_id ] );
 
 			if ( ! $coupon_id ) {
-				$coupon_items_count--;
+				// Insert a unique, but obviously invalid ID for this deleted coupon.
-				continue;
+				$num_deleted++;
+				$coupon_id = -1 * $num_deleted;
 			}
 
 			$result = $wpdb->replace(
@@ -422,27 +457,6 @@ class DataStore extends ReportsDataStore implements DataStoreInterface {
 		ReportsCache::invalidate();
 	}
 
-	/**
-	 * Deletes the coupon lookup information when a coupon is deleted.
-	 * This keeps data consistent if it gets resynced at any point.
-	 *
-	 * @param int $post_id Post ID.
-	 */
-	public static function delete_coupon( $post_id ) {
-		global $wpdb;
-
-		if ( 'shop_coupon' !== get_post_type( $post_id ) ) {
-			return;
-		}
-
-		$wpdb->delete(
-			self::get_db_table_name(),
-			array( 'coupon_id' => $post_id )
-		);
-
-		ReportsCache::invalidate();
-	}
-
 	/**
 	 * Gets coupons based on the provided arguments.
 	 *

plugins/woocommerce-admin/src/Install.php

@@ -237,7 +237,7 @@ class Install {
 		) $collate;
 		CREATE TABLE {$wpdb->prefix}wc_order_coupon_lookup (
 			order_id BIGINT UNSIGNED NOT NULL,
-			coupon_id BIGINT UNSIGNED NOT NULL,
+			coupon_id BIGINT NOT NULL,
 			date_created datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
 			discount_amount double DEFAULT 0 NOT NULL,
 			PRIMARY KEY (order_id, coupon_id),

plugins/woocommerce-admin/tests/reports/class-wc-tests-reports-coupons-stats.php

@@ -60,8 +60,8 @@ class WC_Tests_Reports_Coupons_Stats extends WC_Unit_Test_Case {
 		WC_Helper_Queue::run_all_pending();
 
 		$data_store = new CouponsStatsDataStore();
-		$start_time = date( 'Y-m-d 00:00:00', $order->get_date_created()->getOffsetTimestamp() );
+		$start_time = gmdate( 'Y-m-d 00:00:00', $order->get_date_created()->getOffsetTimestamp() );
-		$end_time   = date( 'Y-m-d 23:59:59', $order->get_date_created()->getOffsetTimestamp() );
+		$end_time   = gmdate( 'Y-m-d 23:59:59', $order->get_date_created()->getOffsetTimestamp() );
 		$args       = array(
 			'after'    => $start_time,
 			'before'   => $end_time,
@@ -104,4 +104,75 @@ class WC_Tests_Reports_Coupons_Stats extends WC_Unit_Test_Case {
 		$query = new CouponsStatsQuery( $args );
 		$this->assertEquals( $expected_data, $query->get_data() );
 	}
+
+	/**
+	 * Test that deleted coupon are still included in reports.
+	 */
+	public function test_deleted_coupon() {
+		WC_Helper_Reports::reset_stats_dbs();
+
+		// Simple product.
+		$product = new WC_Product_Simple();
+		$product->set_name( 'Test Product' );
+		$product->set_regular_price( 35 );
+		$product->save();
+
+		// Coupons.
+		$coupon_1_amount = 5;
+		$coupon_1        = WC_Helper_Coupon::create_coupon( 'coupon_1' );
+		$coupon_1->set_amount( $coupon_1_amount );
+		$coupon_1->save();
+
+		// Order with 1 coupon.
+		$order = WC_Helper_Order::create_order( 1, $product );
+		$order->set_status( 'completed' );
+		$order->apply_coupon( $coupon_1 );
+		$order->calculate_totals();
+		$order->save();
+
+		// Delete the coupon.
+		$coupon_1->delete( true );
+
+		WC_Helper_Queue::run_all_pending();
+
+		$start_time = gmdate( 'Y-m-d 00:00:00', $order->get_date_created()->getOffsetTimestamp() );
+		$end_time   = gmdate( 'Y-m-d 23:59:59', $order->get_date_created()->getOffsetTimestamp() );
+		$args       = array(
+			'after'    => $start_time,
+			'before'   => $end_time,
+			'interval' => 'day',
+		);
+
+		// Test retrieving the stats through the query class.
+		$query          = new CouponsStatsQuery( $args );
+		$start_datetime = new DateTime( $start_time );
+		$end_datetime   = new DateTime( $end_time );
+		$expected_data  = (object) array(
+			'total'     => 1,
+			'pages'     => 1,
+			'page_no'   => 1,
+			'totals'    => (object) array(
+				'amount'        => floatval( $coupon_1_amount ),
+				'coupons_count' => 1,
+				'orders_count'  => 1,
+				'segments'      => array(),
+			),
+			'intervals' => array(
+				array(
+					'interval'       => $start_datetime->format( 'Y-m-d' ),
+					'date_start'     => $start_datetime->format( 'Y-m-d H:i:s' ),
+					'date_start_gmt' => $start_datetime->format( 'Y-m-d H:i:s' ),
+					'date_end'       => $end_datetime->format( 'Y-m-d H:i:s' ),
+					'date_end_gmt'   => $end_datetime->format( 'Y-m-d H:i:s' ),
+					'subtotals'      => (object) array(
+						'amount'        => floatval( $coupon_1_amount ),
+						'coupons_count' => 1,
+						'orders_count'  => 1,
+						'segments'      => array(),
+					),
+				),
+			),
+		);
+		$this->assertEquals( $expected_data, $query->get_data() );
+	}
 }

plugins/woocommerce-admin/tests/reports/class-wc-tests-reports-coupons.php

@@ -62,8 +62,8 @@ class WC_Tests_Reports_Coupons extends WC_Unit_Test_Case {
 		WC_Helper_Queue::run_all_pending();
 
 		$data_store = new CouponsDataStore();
-		$start_time = date( 'Y-m-d 00:00:00', $order->get_date_created()->getOffsetTimestamp() );
+		$start_time = gmdate( 'Y-m-d 00:00:00', $order->get_date_created()->getOffsetTimestamp() );
-		$end_time   = date( 'Y-m-d 23:59:59', $order->get_date_created()->getOffsetTimestamp() );
+		$end_time   = gmdate( 'Y-m-d 23:59:59', $order->get_date_created()->getOffsetTimestamp() );
 		$args       = array(
 			'after'  => $start_time,
 			'before' => $end_time,
@@ -288,7 +288,7 @@ class WC_Tests_Reports_Coupons extends WC_Unit_Test_Case {
 			$coupon_2_response['orders_count'],
 			$coupon_2_response['amount'],
 			$coupon_2_response['extended_info']['date_created'],
-			$coupon_2_response['extended_info']['date_expires'] ? : 'N/A',
+			$coupon_2_response['extended_info']['date_expires'] ? $coupon_2_response['extended_info']['date_expires'] : 'N/A',
 			$coupon_2_response['extended_info']['discount_type'],
 		);
 
@@ -298,7 +298,7 @@ class WC_Tests_Reports_Coupons extends WC_Unit_Test_Case {
 			$coupon_1_response['orders_count'],
 			$coupon_1_response['amount'],
 			$coupon_1_response['extended_info']['date_created'],
-			$coupon_1_response['extended_info']['date_expires'] ? : 'N/A',
+			$coupon_1_response['extended_info']['date_expires'] ? $coupon_1_response['extended_info']['date_expires'] : 'N/A',
 			$coupon_1_response['extended_info']['discount_type'],
 		);
 
@@ -320,4 +320,196 @@ class WC_Tests_Reports_Coupons extends WC_Unit_Test_Case {
 		$this->assertEquals( 2, $export->get_total_exported() );
 		$this->assertEquals( $expected_csv, $actual_csv );
 	}
+
+	/**
+	 * Test that calculations and querying works correctly when coupons are deleted.
+	 */
+	public function test_deleted_coupons() {
+		WC_Helper_Reports::reset_stats_dbs();
+
+		// Simple product.
+		$product = new WC_Product_Simple();
+		$product->set_name( 'Test Product' );
+		$product->set_regular_price( 25 );
+		$product->save();
+
+		// Coupons.
+		$coupon_1_amount = 3; // by default in create_coupon.
+		$coupon_1        = WC_Helper_Coupon::create_coupon( 'coupon_1' );
+		$coupon_1->set_amount( $coupon_1_amount );
+		$coupon_1->save();
+
+		// Coupon that will be deleted.
+		$coupon_2_amount = 7;
+		$coupon_2        = WC_Helper_Coupon::create_coupon( 'coupon_2' );
+		$coupon_2->set_amount( $coupon_2_amount );
+		$coupon_2->save();
+
+		// Coupon that will be deleted, but order item will have metadata that will preserve its ID.
+		$coupon_3_amount = 1;
+		$coupon_3        = WC_Helper_Coupon::create_coupon( 'coupon_3' );
+		$coupon_3->set_amount( $coupon_3_amount );
+		$coupon_3->save();
+		$coupon_3_id = $coupon_3->get_id();
+
+		// Order with coupons.
+		$order = WC_Helper_Order::create_order( 1, $product );
+		$order->set_status( 'completed' );
+		$order->apply_coupon( $coupon_1 );
+		$order->apply_coupon( $coupon_2 );
+		$order->apply_coupon( $coupon_3 );
+		$order->calculate_totals();
+		$order->save();
+
+		// Add coupon_3 metadata to its order item.
+		$coupon_items = $order->get_items( 'coupon' );
+
+		// This would normally happen at checkout.
+		foreach ( $coupon_items as $coupon_item ) {
+			if ( 'coupon_3' !== $coupon_item->get_code() ) {
+				continue;
+			}
+
+			$coupon_3_data = $coupon_3->get_data();
+			unset( $coupon_3_data['used_by'] );
+			$coupon_item->add_meta_data( 'coupon_data', $coupon_3_data );
+			$coupon_item->save();
+		}
+
+		// Delete the coupons.
+		$coupon_2->delete( true );
+		$coupon_3->delete( true );
+
+		WC_Helper_Queue::run_all_pending();
+
+		$data_store = new CouponsDataStore();
+		$start_time = gmdate( 'Y-m-d 00:00:00', $order->get_date_created()->getOffsetTimestamp() );
+		$end_time   = gmdate( 'Y-m-d 23:59:59', $order->get_date_created()->getOffsetTimestamp() );
+		$args       = array(
+			'after'  => $start_time,
+			'before' => $end_time,
+		);
+
+		// Test retrieving the stats through the data store.
+		$coupon_1_response = array(
+			'coupon_id'     => $coupon_1->get_id(),
+			'amount'        => floatval( $coupon_1_amount ),
+			'orders_count'  => 1,
+			'extended_info' => new ArrayObject(),
+		);
+		$coupon_2_response = array(
+			'coupon_id'     => -1, // coupon_2 was deleted, so a new ID was created.
+			'amount'        => floatval( $coupon_2_amount ),
+			'orders_count'  => 1,
+			'extended_info' => new ArrayObject(),
+		);
+		$coupon_3_response = array(
+			'coupon_id'     => $coupon_3_id, // coupon_3 was deleted, but has metadata containing the ID.
+			'amount'        => floatval( $coupon_3_amount ),
+			'orders_count'  => 1,
+			'extended_info' => new ArrayObject(),
+		);
+
+		// Order by coupon id DESC is the default.
+		$data          = $data_store->get_data( $args );
+		$expected_data = (object) array(
+			'total'   => 3,
+			'pages'   => 1,
+			'page_no' => 1,
+			'data'    => array(
+				// Order is 3, 1, 2 since query is sorted by coupon ID descending.
+				0 => $coupon_3_response,
+				1 => $coupon_1_response,
+				2 => $coupon_2_response,
+			),
+		);
+		$this->assertEquals( $expected_data, $data );
+
+		// Test extended info.
+		$gmt_timezone    = new DateTimeZone( 'UTC' );
+		$c1_date_created = $coupon_1->get_date_created();
+		if ( null === $c1_date_created ) {
+			$c1_date_created     = '';
+			$c1_date_created_gmt = '';
+		} else {
+			$c1_date_created_gmt = new DateTime( $c1_date_created );
+			$c1_date_created_gmt->setTimezone( $gmt_timezone );
+
+			$c1_date_created     = $c1_date_created->format( TimeInterval::$iso_datetime_format );
+			$c1_date_created_gmt = $c1_date_created_gmt->format( TimeInterval::$iso_datetime_format );
+		}
+
+		$c1_date_expires = $coupon_1->get_date_expires();
+		if ( null === $c1_date_expires ) {
+			$c1_date_expires     = '';
+			$c1_date_expires_gmt = '';
+		} else {
+			$c1_date_expires_gmt = new DateTime( $c1_date_expires );
+			$c1_date_expires_gmt->setTimezone( $gmt_timezone );
+
+			$c1_date_expires     = $c1_date_expires->format( TimeInterval::$iso_datetime_format );
+			$c1_date_expires_gmt = $c1_date_expires_gmt->format( TimeInterval::$iso_datetime_format );
+		}
+
+		$coupon_1_response = array(
+			'coupon_id'     => $coupon_1->get_id(),
+			'amount'        => floatval( $coupon_1_amount ),
+			'orders_count'  => 1,
+			'extended_info' => array(
+				'code'             => $coupon_1->get_code(),
+				'date_created'     => $c1_date_created,
+				'date_created_gmt' => $c1_date_created_gmt,
+				'date_expires'     => $c1_date_expires,
+				'date_expires_gmt' => $c1_date_expires_gmt,
+				'discount_type'    => $coupon_1->get_discount_type(),
+			),
+		);
+
+		$coupon_2_response = array(
+			'coupon_id'     => -1,
+			'amount'        => floatval( $coupon_2_amount ),
+			'orders_count'  => 1,
+			'extended_info' => array(
+				'code'             => '(Deleted)',
+				'date_created'     => '',
+				'date_created_gmt' => '',
+				'date_expires'     => '',
+				'date_expires_gmt' => '',
+				'discount_type'    => 'N/A',
+			),
+		);
+
+		$coupon_3_response = array(
+			'coupon_id'     => $coupon_3_id, // coupon_3 was deleted, but has metadata containing the ID.
+			'amount'        => floatval( $coupon_3_amount ),
+			'orders_count'  => 1,
+			'extended_info' => array(
+				'code'             => '(Deleted)',
+				'date_created'     => '',
+				'date_created_gmt' => '',
+				'date_expires'     => '',
+				'date_expires_gmt' => '',
+				'discount_type'    => 'N/A',
+			),
+		);
+
+		$args          = array(
+			'after'         => $start_time,
+			'before'        => $end_time,
+			'extended_info' => true,
+		);
+		$data          = $data_store->get_data( $args );
+		$expected_data = (object) array(
+			'total'   => 3,
+			'pages'   => 1,
+			'page_no' => 1,
+			'data'    => array(
+				// Order is 3, 1, 2 since query is sorted by coupon ID descending.
+				0 => $coupon_3_response,
+				1 => $coupon_1_response,
+				2 => $coupon_2_response,
+			),
+		);
+		$this->assertEquals( $expected_data, $data );
+	}
 }