gistfile1.txt

<?php

// You can copy&paste the contents of the script to your (child) themes functions.php. I recommend doing it over FTP.

remove_all_filters( 'wafs_match_condition_category' );
add_filter( 'wafs_match_condition_category', 'new_wafs_match_condition_category', 10, 3 );
/**
 * Stock status.
 *
 * Match the stock status to one or more products in the cart.
 *
 * @global object $woocommerce WooCommerce object.
 *
 * @param 	bool 	$match		Current match value.
 * @param 	string 	$operator	Operator selected by the user in the condition row.
 * @param 	mixed 	$value		Value given by the user in the condition row.
 * @return 	BOOL 				Matching result, TRUE if results match, otherwise FALSE.
 */
function new_wafs_match_condition_category( $match, $operator, $value ) {

	if ( ! isset( WC()->cart ) ) return;

	$term 			= get_term_by( 'slug', $value, 'product_cat' );
	$term_childs 	= get_term_children( $term->term_id, 'product_cat' );

	$term_slugs = array( $term->slug );
	foreach ( $term_childs as $child ) :
		$term 			= get_term_by( 'id', $child, 'product_cat' );
		$term_slugs[] 	= $term->slug;
	endforeach;

	if ( '==' == $operator ) :

		foreach ( WC()->cart->cart_contents as $product ) :

			// Get product terms
			$product_terms = get_the_terms( $product['product_id'], 'product_cat' );
			$product_terms = wp_list_pluck( $product_terms, 'slug' );

			if ( count( array_intersect( $product_terms, $term_slugs ) ) >= 1 ) :
				$match = true;
			endif;

		endforeach;

	elseif ( '!=' == $operator ) :

		$match = true;
		foreach ( WC()->cart->cart_contents as $product ) :

			// Get product terms
			$product_terms = get_the_terms( $product['product_id'], 'product_cat' );
			$product_terms = wp_list_pluck( $product_terms, 'slug' );

			if ( count( array_intersect( $product_terms, $term_slugs ) ) >= 1 ) :
				$match = true;
			endif;

		endforeach;

	endif;

	return $match;

}