$error variable in login action is probably undefined all the time

[nextendweb]

In wp-login.php in the following code, the $error variable probably always evaluated as false as there is no global $error; anywhere. Is the code ok or it does not required anymore?

<?php
/**
 * Filters whether to print the call to `wp_attempt_focus()` on the login screen.
 *
 * @since 4.8.0
 *
 * @param bool $print Whether to print the function call. Default true.
 */
if ( apply_filters( 'enable_login_autofocus', true ) && ! $error ) { ?>
wp_attempt_focus();
<?php } ?>

[SergeyBiryukov]

Hi @nextendweb, thanks for the ticket!

The $error global used to be set in the wp_login() pluggable function, which is unused since [6643] and was formally deprecated in [13093].

The check in question was left for backward compatibility. The global is also checked in login_header()​.

A brief search in the Plugin Directory shows that some plugins still use the global, so I guess it's better to leave it as is for the time being.