Filter for custom sale price for trip extras enable/disable.

Source

File: /core/lib/cart.php
Used by: /core/lib/cart.php, /inc/cart/class-cart.php

Parameters
$sale_price, $e_id, $trip[‘trip_id’]

Example:

function prefix_wp_travel_trip_extras_custom_sale_prices() {
    return true;
}
add_filter( 'wp_travel_trip_extras_custom_sale_prices', 'prefix_wp_travel_trip_extras_custom_sale_prices' );