WooCommerce: hide shipping when products marked as "local pickup only" are in the cart

woocommerce-local-pickup-only.php

<?php
/**
 * WooCommerce: hide shipping when products marked as "local pickup only" are in the cart
 * Tested with WordPress 5.3.4 and WooCommerce 4.2.0
 *
 * The shipping class "local-pickup-only" needs to be created first.
 * Then assign the products that are have "local pickup only" to this class
 *
 * @param array $rates
 * @param array $package
 *
 * @return array
 */
function custom_woocommerce_hide_shipping_on_local_pickup_required( $rates, $package )
{
	$shipping_class_local_pickup_only = 'local-pickup-only';
	
	$local = [];

	foreach( $package['contents'] as $item )
	{
		$product = $item['data'];
		$shipping_class = $product->get_shipping_class();

		if( $shipping_class == $shipping_class_local_pickup_only )
		{
			foreach( $rates as $rate_id => $rate )
			{
				if( in_array( $rate->method_id, array( 'local_pickup', 'legacy_local_pickup' ) ) )
				{
					$local[ $rate_id ] = $rate;
					break;
				}
			}
		}
	}

	return !empty( $local ) ? $local : $rates;
}

add_filter( 'woocommerce_package_rates', 'custom_woocommerce_hide_shipping_on_local_pickup_required', 10, 2 );