prevent php8-warnings, closes #3475

Closes #3475

Merge request studip/studip!2371

app/views/questionnaire/question_types/likert/likert_evaluation.php

@@ -27,6 +27,7 @@ $options = $vote->questiondata['options'];
     </thead>
     <tbody>
         <? $countAnswers = $vote->questionnaire->countAnswers() ?>
+        <? if (!empty($vote->questiondata['statements'])) : ?>
             <? foreach ($vote->questiondata['statements'] as $key => $statement) : ?>
             <tr>
                 <td>
@@ -66,5 +67,6 @@ $options = $vote->questiondata['options'];
                 <? endforeach ?>
             </tr>
         <? endforeach ?>
+    <? endif ?>
     </tbody>
 </table>

lib/models/LikertScale.php

@@ -32,7 +32,7 @@ class LikertScale extends QuestionnaireQuestion implements QuestionType
         $questiondata['description'] = \Studip\Markup::markAsHtml(
             \Studip\Markup::purifyHtml($questiondata['description'])
         );
-        $questiondata['statements'] = array_filter($questiondata['statements']);
+        $questiondata['statements'] = array_filter($questiondata['statements'] ?? []);
         return $questiondata;
     }
 

lib/models/RangeScale.php

@@ -27,7 +27,7 @@ class RangeScale extends QuestionnaireQuestion implements QuestionType
         $questiondata['description'] = \Studip\Markup::markAsHtml(
             \Studip\Markup::purifyHtml($questiondata['description'])
         );
-        $questiondata['statements'] = array_filter($questiondata['statements']);
+        $questiondata['statements'] = array_filter($questiondata['statements'] ?? []);
         return $questiondata;
     }