WordPress at a glance
filter is not described

woocommerce_checkout_update_customer_data filter-hook . WC 1.0

Add customer info from other fields.

Usage

add_filter( 'woocommerce_checkout_update_customer_data', 'filter_function_name_7382', 10, 2 );
function filter_function_name_7382( $true, $that ){
	// filter...

	return $true;
}
$true
-
$that
-

Where the hook is called

WC_Checkout::process_customer()
woocommerce_checkout_update_customer_data
woocommerce/includes/class-wc-checkout.php 1056
if ( $customer_id && apply_filters( 'woocommerce_checkout_update_customer_data', true, $this ) ) {

Where in WP core the hook is used WooCommerce

Usage not found.