wp_apply_custom_classname_support( WP_Block_Type $block_type, array $block_attributes ): array

44function wp_apply_custom_classname_support( $block_type, $block_attributes ) {45	$has_custom_classname_support = block_has_support( $block_type, 'customClassName', true );46	$attributes                   = array();47	if ( $has_custom_classname_support ) {48		$has_custom_classnames = array_key_exists( 'className', $block_attributes );49 50		if ( $has_custom_classnames ) {51			$attributes['class'] = $block_attributes['className'];52		}53	}54 55	return $attributes;56}