On ajoute deux champs de type text à l'onglet "Avancé" de la metabox produit WooCommerce

functions.php

/*************************************************************************************************
* On ajoute 2 champs (post meta ou custom field) aux produits WC dans l'onglet "Avancé"
*************************************************************************************************/
function msk_add_loves_hates_fields_to_product() {
	woocommerce_wp_text_input(
		array(
			'id' => 'loves', 
			'data_type' => 'decimal', 
			'label' => __('Loves', 'msk'),
			'placeholder' => __('Amount of love', 'msk'),
			'description' => __('Love this product has received.', 'msk'),
			'desc_tip' => true
		)
	);

	woocommerce_wp_text_input(
		array(
			'id' => 'hates', 
			'data_type' => 'decimal', 
			'label' => __('Hates', 'msk'),
			'placeholder' => __('Amount of hate', 'msk'),
			'description' => __('Hatred this product has received.', 'msk'),
			'desc_tip' => true
		)
	);
}
add_action('woocommerce_product_options_advanced', 'msk_add_loves_hates_fields_to_product');