wp_unique_term_slug_is_bad_slug filter-hook . WP 4.3.0

Filters whether the proposed unique term slug is bad.

Usage

add_filter( 'wp_unique_term_slug_is_bad_slug', 'filter_function_name_4548', 10, 3 );
function filter_function_name_4548( $needs_suffix, $slug, $term ){
	// filter...

	return $needs_suffix;
}

$needs_suffix(true|false)

Whether the slug needs to be made unique with a suffix.

$slug(string)

The slug.

$term(object)

Term object.

Where the hook is called

if ( apply_filters( 'wp_unique_term_slug_is_bad_slug', $needs_suffix, $slug, $term ) ) {

Where in WP core the hook is used WordPress