Enable WP_DEBUG, WP_DEBUG_DISPLAY, & WP_DEBUG_LOG on a site where FTP/SFTP access is not currently available.

tk-enable-wp-debug.php

<?php
/**
 * Plugin Name: TK Enable WP_DEBUG and Such
 * Plugin URI:  https://gist.github.com/cliffordp/c4c4bb32cf30b64f565c1d0332e1e945/edit
 * Description: Enable WP_DEBUG and such. Useful for sites without FTP/SFTP access. No settings page; just deactivate to disable.
 * Version:     1.0.0
 * Author:      TourKick LLC (Clifford Paulick)
 * Author URI:  https://tourkick.com/
 * License:     GPL version 3 or any later version
 * License URI: https://www.gnu.org/licenses/gpl-3.0.html
 */

// If this file is called directly, abort.
if ( ! defined( 'WPINC' ) ) {
	die;
}

if (
	! defined( 'WP_DEBUG' )
	|| empty( WP_DEBUG )
) {
	define( 'WP_DEBUG', true );
}

if (
	! defined( 'WP_DEBUG_DISPLAY' )
	|| empty( WP_DEBUG_DISPLAY )
) {
	define( 'WP_DEBUG_DISPLAY', true );
}

// TODO: if we do not have FTP access, why enable this? Is it accessible via URL?
if (
	! defined( 'WP_DEBUG_LOG' )
	|| empty( WP_DEBUG_LOG )
) {
	define( 'WP_DEBUG_LOG', true );
}

@error_reporting( E_ALL | E_STRICT );
@ini_set( 'display_errors', true );
@ini_set( 'log_errors_max_len', '0' );

// Unlimited length var_dump()
@ini_set( 'xdebug.var_display_max_depth', -1 );
@ini_set( 'xdebug.var_display_max_children', -1 );
@ini_set( 'xdebug.var_display_max_data', -1 );