%s', esc_url( $product->add_to_cart_url() ), esc_attr( isset( $quantity ) ? $quantity : 1 ), esc_attr( $product->get_id() ), esc_attr( $product->get_sku() ), esc_attr( isset( $class ) ? $class . ' btn btn-sm btn-add-to-cart' : 'btn btn-sm btn-add-to-cart' ), esc_html( $product->add_to_cart_text() ) ), $product );