diff --git a/core/modules/search/lib/Drupal/search/Plugin/views/filter/Search.php b/core/modules/search/lib/Drupal/search/Plugin/views/filter/Search.php
index afb7724..b976d81 100644
--- a/core/modules/search/lib/Drupal/search/Plugin/views/filter/Search.php
+++ b/core/modules/search/lib/Drupal/search/Plugin/views/filter/Search.php
@@ -48,7 +48,7 @@ protected function defineOptions() {
   /**
    * Provide simple equality operator
    */
-  function operator_form(&$form, &$form_state) {
+  function operatorForm(&$form, &$form_state) {
     $form['operator'] = array(
       '#type' => 'radios',
       '#title' => t('On empty input'),