This function exists since 5.6.1.

Author: johnbillion

collectors/environment.php

@@ -224,12 +224,9 @@ public function process() {
 			'host' => null,
 			'OS' => null,
 			'arch' => null,
+			'basicauth' => wp_is_site_protected_by_basic_auth() ? 'true' : 'false',
 		);
 
-		if ( function_exists( 'wp_is_site_protected_by_basic_auth' ) ) {
-			$this->data->server['basicauth'] = wp_is_site_protected_by_basic_auth() ? 'true' : 'false';
-		}
-
 		if ( function_exists( 'php_uname' ) ) {
 			$this->data->server['host'] = php_uname( 'n' );
 			$this->data->server['OS'] = php_uname( 's' ) . ' ' . php_uname( 'r' );

data/environment.php

@@ -62,6 +62,7 @@ class QM_Data_Environment extends QM_Data {
 	 *   host: string|null,
 	 *   OS: string|null,
 	 *   arch: string|null,
+	 *   basicauth: 'true'|'false',
 	 * }>
 	 */
 	public $server;