prevent many warnings regarding php8 on main, fixes #4631

Closes #4631

Merge request studip/studip!3448

2 files changed, 7 insertions, 6 deletions

diff --git a/lib/classes/coursewizardsteps/AdvancedBasicDataWizardStep.php b/lib/classes/coursewizardsteps/AdvancedBasicDataWizardStep.php
index 780f837..9e364e6 100644
--- a/lib/classes/coursewizardsteps/AdvancedBasicDataWizardStep.php
+++ b/lib/classes/coursewizardsteps/AdvancedBasicDataWizardStep.php
@@ -31,7 +31,7 @@ class AdvancedBasicDataWizardStep extends BasicDataWizardStep
         $values = $this->adjustValues($values);
 
        // We only need our own stored values here.
-        if ($values[__CLASS__]['studygroup']) {
+        if (!empty($values[__CLASS__]['studygroup'])) {
             return parent::getStepTemplate($values, $stepnumber, $temp_id);
         }
 
@@ -44,7 +44,7 @@ class AdvancedBasicDataWizardStep extends BasicDataWizardStep
             return '';
         }
 
-        $values = $this->makeI18N($values[__CLASS__], ['name', 'description', 'subtitle', 'kind']);
+        $values = $this->makeI18N($values[__CLASS__] ?? [], ['name', 'description', 'subtitle', 'kind']);
 
         $template->set_attribute('values', array_merge($template->values, $values));
 
@@ -83,7 +83,7 @@ class AdvancedBasicDataWizardStep extends BasicDataWizardStep
         }
 
         // Studygroup? -> nothing to do here
-        if ($values[__CLASS__]['studygroup']) {
+        if (!empty($values[__CLASS__]['studygroup'])) {
             return $course;
         }
 
@@ -117,7 +117,7 @@ class AdvancedBasicDataWizardStep extends BasicDataWizardStep
         if (!isset($values[__CLASS__]) && isset($values[$parent_class])) {
             $values[__CLASS__] = $values[$parent_class];
         } else {
-            $values[$parent_class] = $values[__CLASS__];
+            $values[$parent_class] = $values[__CLASS__] ?? [];
         }
 
         return $values;
diff --git a/lib/classes/coursewizardsteps/BasicDataWizardStep.php b/lib/classes/coursewizardsteps/BasicDataWizardStep.php
index fe7364a..ec441eb 100644
--- a/lib/classes/coursewizardsteps/BasicDataWizardStep.php
+++ b/lib/classes/coursewizardsteps/BasicDataWizardStep.php
@@ -534,9 +534,10 @@ class BasicDataWizardStep implements CourseWizardStep
         }
     }
 
-    public function getSearch($course_type, $institute_ids, $exclude_lecturers = [],$exclude_tutors = [])
+    public function getSearch($course_type)
     {
-        if (SeminarCategories::getByTypeId($course_type)->only_inst_user) {
+        $category = SeminarCategories::getByTypeId($course_type);
+        if ($category && $category->only_inst_user) {
             $search = 'user_inst';
         } else {
             $search = 'user';