Minor - validate parameter

main/exercise/exercise.class.php

@@ -771,6 +771,10 @@ class Exercise
      */
     public function getQuestionOrderedListByName()
     {
+        if (empty($this->course_id) || empty($this->id)) {
+            return [];
+        }
+
         $exerciseQuestionTable = Database::get_course_table(TABLE_QUIZ_TEST_QUESTION);
         $questionTable = Database::get_course_table(TABLE_QUIZ_QUESTION);
 

main/inc/lib/document.lib.php

@@ -535,6 +535,11 @@ class DocumentManager
         $search = false,
         $sessionId = 0
     ) {
+
+        if (empty($courseInfo)) {
+            return [];
+        }
+
         $tblItemProperty = Database::get_course_table(TABLE_ITEM_PROPERTY);
         $tblDocument = Database::get_course_table(TABLE_DOCUMENT);