hide-coupon-for-categories.php

<?php

add_filter( 'woocommerce_coupons_enabled','ts_hide_coupon_field_on_cart' );
function ts_hide_coupon_field_on_cart( $enabled ) {

	$product_categories = array('hd', 'led');
	$cart = WC()->cart->get_cart();
	foreach ( $cart as $id => $cart_item ) {
		$_product = wc_get_product($cart_item[ 'data' ]->get_id() );

		foreach( $product_categories as $category ) {
			if( has_term( $category, 'product_cat', $cart_item[ 'data' ]->get_id() ) ) {
				return false;
			}
		}
	}	

	
	return $enabled;
}