Minor: improved return value to be able to manage errors more gracefully in exercises results

main/exercice/exercise.class.php

@@ -1935,6 +1935,9 @@ class Exercise {
 		// Creates a temporary Question object
 		$course_id              = api_get_course_int_id();
 		$objQuestionTmp         = Question::read($questionId, $course_id);
+                if ($objQuestionTmp === false) {
+                    return false;
+                }
 
 		$questionName 			= $objQuestionTmp->selectTitle();
 		$questionWeighting 		= $objQuestionTmp->selectWeighting();

main/exercice/exercise.lib.php

@@ -2137,6 +2137,9 @@ function display_question_list_by_attempt($objExercise, $exe_id, $save_user_resu
 
             // We're inside *one* question. Go through each possible answer for this question
             $result = $objExercise->manage_answer($exercise_stat_info['exe_id'], $questionId, null, 'exercise_result', array(), $save_user_result, true, $show_results, $objExercise->selectPropagateNeg(), $hotspot_delineation_result);
+            if (empty($result)) {
+                continue;
+            }
 
             $total_score     += $result['score'];
             $total_weight    += $result['weight'];
@@ -2289,4 +2292,4 @@ function get_question_ribbon($objExercise, $score, $weight, $check_pass_percenta
 
     $ribbon .= '</div>';
     return $ribbon;
-}
+}

main/exercice/question.class.php

@@ -1602,4 +1602,4 @@ abstract class Question
         }
         return $html;
     }
-}
+}