Custom Taxonomy Support added to Product edit form for WC Vendors Pro

functions.php

<?php 

function form_subjects( $object_id ) { 

 WCVendors_Pro_Form_helper::select2( array(
			'post_id'			=> $object_id,
			'id'				=> '_wcv_custom_taxonomy_subjects[]',
			'class'				=> 'select2',
			'label'				=> __('Subjects', 'wcvendors-pro'),
			'show_option_none'	=> __('Select Subject(s)', 'wcvendors-pro'),
			'taxonomy'			=>	'subjects', 
			'taxonomy_args'		=> array( 
									'hide_empty'	=> 0, 
								),
			'custom_attributes'	=> array( 'multiple' => 'multiple' ), 
			)
	); 
}

function save_subjects( $post_id ){ 

	if ( isset( $_POST[ '_wcv_custom_taxonomy_subjects' ] ) && is_array( $_POST[ '_wcv_custom_taxonomy_subjects' ] ) ) { 
		$subjects = array_map( 'intval', $_POST[ '_wcv_custom_taxonomy_subjects' ] ); 
		$subjects = array_unique( $subjects ); 
		wp_set_post_terms( $post_id, $subjects, 'subjects' ); 
	} 
}

add_action( 'wcv_save_product', 'save_subjects' );


?>