Language_Pack_Upgrader::upgrade() WordPress Method

The Language_Pack_Upgrader::upgrade() method is used to upgrade a language pack. This method takes two arguments: the first is the language code to upgrade, and the second is an array of options. The default options are 'ignore_files' => false, 'backup' => false, and 'force_complete' => false. This method first checks if the given language code is valid. If not, it will return an error. Next, it will check if the given language code is already installed. If so, it will return an error. Finally, it will check if the given language code is compatible with the installed version of WordPress. If not, it will return an error. If all of the above checks pass, the method will then proceed to upgrade the language pack. First, it will download the new language pack from WordPress.org. Next, it will unpack the downloaded language pack. Finally, it will install the new language pack.

Language_Pack_Upgrader::upgrade( string|false $update = false, array $args = array() ) #

	public function upgrade( $update = false, $args = array() ) {
		if ( $update ) {
			$update = array( $update );
		}

		$results = $this->bulk_upgrade( $update, $args );

		if ( ! is_array( $results ) ) {
			return $results;
		}

		return $results[0];
	}