MDL-39167 quiz access rules: need to validate their settings.

We were missing the hook in the form validation method. We had them
everywhere else they were needed.

mod/quiz/accessmanager.php

@@ -123,6 +123,24 @@ class quiz_access_manager {
         return $options;
     }
 
+    /**
+     * Validate the data from any form fields added using {@link add_settings_form_fields()}.
+     * @param array $errors the errors found so far.
+     * @param array $data the submitted form data.
+     * @param array $files information about any uploaded files.
+     * @param mod_quiz_mod_form $quizform the quiz form object.
+     * @return array $errors the updated $errors array.
+     */
+    public static function validate_settings_form_fields(array $errors,
+            array $data, $files, mod_quiz_mod_form $this) {
+
+        foreach (self::get_rule_classes() as $rule) {
+            $errors = $rule::validate_settings_form_fields($errors, $data, $files, $this);
+        }
+
+        return $errors;
+    }
+
     /**
      * Save any submitted settings when the quiz settings form is submitted.
      *

mod/quiz/accessrule/accessrulebase.php

@@ -256,6 +256,20 @@ abstract class quiz_access_rule_base {
         // By default do nothing.
     }
 
+    /**
+     * Validate the data from any form fields added using {@link add_settings_form_fields()}.
+     * @param array $errors the errors found so far.
+     * @param array $data the submitted form data.
+     * @param array $files information about any uploaded files.
+     * @param mod_quiz_mod_form $quizform the quiz form object.
+     * @return array $errors the updated $errors array.
+     */
+    public static function validate_settings_form_fields(array $errors,
+            array $data, $files, mod_quiz_mod_form $quizform) {
+
+        return $errors;
+    }
+
     /**
      * @return array key => lang string any choices to add to the quiz Browser
      *      security settings menu.

mod/quiz/mod_form.php

@@ -575,6 +575,9 @@ class mod_quiz_mod_form extends moodleform_mod {
             }
         }
 
+        // Any other rule plugins.
+        $errors = quiz_access_manager::validate_settings_form_fields($errors, $data, $files, $this);
+
         return $errors;
     }
 }