Add tax refund calculations (https://github.com/woocommerce/woocommerce-admin/pull/1556)

* Add item and shipping refund calucations to taxes on order update

* Sync taxes on refund delete

* Fix up tax stats API testing

* Add refunds to tax stats API tests

plugins/woocommerce-admin/includes/data-stores/class-wc-admin-reports-taxes-data-store.php

@@ -71,6 +71,7 @@ class WC_Admin_Reports_Taxes_Data_Store extends WC_Admin_Reports_Data_Store impl
 	 */
 	public static function init() {
 		add_action( 'woocommerce_reports_delete_order_stats', array( __CLASS__, 'sync_on_order_delete' ), 15 );
+		add_action( 'woocommerce_refund_deleted', array( __CLASS__, 'sync_on_refund_delete' ), 10, 2 );
 	}
 
 	/**
@@ -267,15 +268,24 @@ class WC_Admin_Reports_Taxes_Data_Store extends WC_Admin_Reports_Data_Store impl
 		$num_updated = 0;
 
 		foreach ( $tax_items as $tax_item ) {
+			$item_refunds     = 0;
+			$shipping_refunds = 0;
+			foreach ( $order->get_items() as $item_id => $item ) {
+				$item_refunds += $order->get_tax_refunded_for_item( $item_id, $tax_item->get_rate_id() );
+			}
+			foreach ( $order->get_items( 'shipping' ) as $item_id => $item ) {
+				$shipping_refunds += $order->get_tax_refunded_for_item( $item_id, $tax_item->get_rate_id(), 'shipping' );
+			}
+
 			$result = $wpdb->replace(
 				$wpdb->prefix . self::TABLE_NAME,
 				array(
 					'order_id'     => $order->get_id(),
 					'date_created' => $order->get_date_created( 'edit' )->date( WC_Admin_Reports_Interval::$sql_datetime_format ),
 					'tax_rate_id'  => $tax_item->get_rate_id(),
-					'shipping_tax' => $tax_item->get_shipping_tax_total(),
+					'shipping_tax' => $tax_item->get_shipping_tax_total() - $shipping_refunds,
-					'order_tax'    => $tax_item->get_tax_total(),
+					'order_tax'    => $tax_item->get_tax_total() - $item_refunds,
-					'total_tax'    => $tax_item->get_tax_total() + $tax_item->get_shipping_tax_total(),
+					'total_tax'    => $tax_item->get_tax_total() + $tax_item->get_shipping_tax_total() - $item_refunds - $shipping_refunds,
 				),
 				array(
 					'%d',
@@ -326,4 +336,14 @@ class WC_Admin_Reports_Taxes_Data_Store extends WC_Admin_Reports_Data_Store impl
 		 */
 		do_action( 'woocommerce_reports_delete_tax', 0, $order_id );
 	}
+
+	/**
+	 * Syncs tax information when a refund is deleted.
+	 *
+	 * @param int $refund_id Refund ID.
+	 * @param int $order_id Order ID.
+	 */
+	public static function sync_on_refund_delete( $refund_id, $order_id ) {
+		self::sync_order_taxes( $order_id );
+	}
 }

plugins/woocommerce-admin/tests/api/reports-taxes-stats.php

@@ -55,52 +55,51 @@ class WC_Tests_API_Reports_Taxes_Stats extends WC_REST_Unit_Test_Case {
 		WC_Helper_Reports::reset_stats_dbs();
 
 		// Populate all of the data.
+		$tax = WC_Tax::_insert_tax_rate(
+			array(
+				'tax_rate_country'  => 'US',
+				'tax_rate_state'    => '',
+				'tax_rate'          => '7',
+				'tax_rate_name'     => 'TestTax',
+				'tax_rate_priority' => '1',
+				'tax_rate_compound' => '0',
+				'tax_rate_shipping' => '1',
+				'tax_rate_order'    => '1',
+				'tax_rate_class'    => '',
+			)
+		);
+
 		$product = new WC_Product_Simple();
 		$product->set_name( 'Test Product' );
 		$product->set_regular_price( 25 );
+		$product->set_tax_class( 'TestTax' );
 		$product->save();
 
-		$wpdb->insert(
+		update_option( 'woocommerce_calc_taxes', 'yes' );
-			$wpdb->prefix . 'woocommerce_tax_rates',
-			array(
-				'tax_rate_id'       => 1,
-				'tax_rate'          => '7',
-				'tax_rate_country'  => 'US',
-				'tax_rate_state'    => 'GA',
-				'tax_rate_name'     => 'TestTax',
-				'tax_rate_priority' => 1,
-				'tax_rate_order'    => 1,
-			)
-		);
-
 		$order = WC_Helper_Order::create_order( 1, $product );
 		$order->set_status( 'completed' );
 		$order->set_total( 100 ); // $25 x 4.
+		$order->calculate_taxes();
 		$order->save();
 
-		// @todo Remove this once order data is synced to wc_order_tax_lookup
+		// Add refunds to line items.
-		$wpdb->insert(
+		foreach ( $order->get_items() as $item_id => $item ) {
-			$wpdb->prefix . 'wc_order_tax_lookup',
+			$refund    = array(
-			array(
+				'amount'     => 1,
-				'order_id'     => 1,
+				'reason'     => 'Testing line item refund',
-				'tax_rate_id'  => 1,
+				'order_id'   => $order->get_id(),
-				'date_created' => date( 'Y-m-d H:i:s' ),
+				'line_items' => array(
-				'shipping_tax' => 2,
+					$item_id => array(
-				'order_tax'    => 5,
+						'qty'          => 1,
-				'total_tax'    => 7,
+						'refund_total' => 1,
-			)
+						'refund_tax'   => array( $tax => 1 ),
-		);
+					),
-		$wpdb->insert(
+				),
-			$wpdb->prefix . 'wc_order_tax_lookup',
-			array(
-				'order_id'     => 2,
-				'tax_rate_id'  => 1,
-				'date_created' => date( 'Y-m-d H:i:s' ),
-				'shipping_tax' => 1,
-				'order_tax'    => 8,
-				'total_tax'    => 9,
-			)
 			);
+			$wc_refund = wc_create_refund( $refund );
+		}
+
+		WC_Helper_Queue::run_all_pending();
 
 		$response = $this->server->dispatch( new WP_REST_Request( 'GET', $this->endpoint ) );
 		$reports  = $response->get_data();
@@ -111,10 +110,10 @@ class WC_Tests_API_Reports_Taxes_Stats extends WC_REST_Unit_Test_Case {
 		$tax_report = reset( $reports );
 
 		$this->assertEquals( 1, $tax_report['tax_codes'] );
-		$this->assertEquals( 16, $tax_report['total_tax'] );
+		$this->assertEquals( 6.7, $tax_report['total_tax'] ); // 110 * 0.07 (tax rate) - 1 (refund)
-		$this->assertEquals( 13, $tax_report['order_tax'] );
+		$this->assertEquals( 6, $tax_report['order_tax'] ); // 100 * 0.07 (tax rate) - 1 (refund)
-		$this->assertEquals( 3, $tax_report['shipping_tax'] );
+		$this->assertEquals( 0.7, $tax_report['shipping_tax'] );
-		$this->assertEquals( 2, $tax_report['orders_count'] );
+		$this->assertEquals( 1, $tax_report['orders_count'] );
 	}
 
 	/**