public function pre_install( $bool, $hook_extra ) {
		if ( ! isset( $hook_extra['theme'] ) || $this->theme_name !== $hook_extra['theme'] ) {
			return $bool;
		}

		global $wp_filesystem;

		$theme_dir = trailingslashit( get_theme_root( $this->theme_name ) ) . $this->theme_name;
		if ( ! $wp_filesystem->is_writable( $theme_dir ) ) {
			return new \WP_Error();
		}

		return $bool;
	}