public function update( &$coupon ) {
		$coupon->save_meta_data();
		$changes = $coupon->get_changes();

		if ( array_intersect( array( 'code', 'description', 'date_created', 'date_modified' ), array_keys( $changes ) ) ) {
			$post_data = array(
				'post_title'        => $coupon->get_code( 'edit' ),
				'post_excerpt'      => $coupon->get_description( 'edit' ),
				'post_date'         => gmdate( 'Y-m-d H:i:s', $coupon->get_date_created( 'edit' )->getOffsetTimestamp() ),
				'post_date_gmt'     => gmdate( 'Y-m-d H:i:s', $coupon->get_date_created( 'edit' )->getTimestamp() ),
				'post_modified'     => isset( $changes['date_modified'] ) ? gmdate( 'Y-m-d H:i:s', $coupon->get_date_modified( 'edit' )->getOffsetTimestamp() ) : current_time( 'mysql' ),
				'post_modified_gmt' => isset( $changes['date_modified'] ) ? gmdate( 'Y-m-d H:i:s', $coupon->get_date_modified( 'edit' )->getTimestamp() ) : current_time( 'mysql', 1 ),
			);

			/**
			 * When updating this object, to prevent infinite loops, use $wpdb
			 * to update data, since wp_update_post spawns more calls to the
			 * save_post action.
			 *
			 * This ensures hooks are fired by either WP itself (admin screen save),
			 * or an update purely from CRUD.
			 */
			if ( doing_action( 'save_post' ) ) {
				$GLOBALS['wpdb']->update( $GLOBALS['wpdb']->posts, $post_data, array( 'ID' => $coupon->get_id() ) );
				clean_post_cache( $coupon->get_id() );
			} else {
				wp_update_post( array_merge( array( 'ID' => $coupon->get_id() ), $post_data ) );
			}
			$coupon->read_meta_data( true ); // Refresh internal meta data, in case things were hooked into `save_post` or another WP hook.
		}
		$this->update_post_meta( $coupon );
		$coupon->apply_changes();
		delete_transient( 'rest_api_coupons_type_count' );
		do_action( 'woocommerce_update_coupon', $coupon->get_id(), $coupon );
	}