use correct avatar, fixes #3700

Closes #3700

Merge request studip/studip!2569

lib/classes/JsonApi/Schemas/Course.php

@@ -399,10 +399,14 @@ class Course extends SchemaProvider
 
     /**
      * @inheritdoc
+     *
+     * @param \Course $resource
      */
     public function getResourceMeta($resource)
     {
-        $avatar = \CourseAvatar::getAvatar($resource->id);
+        $avatar = $resource->isStudygroup()
+                ? \StudygroupAvatar::getAvatar($resource->id)
+                : \CourseAvatar::getAvatar($resource->id);
 
         return [
             'avatar' => [

tests/jsonapi/CourseShowTest.php

@@ -13,6 +13,9 @@ class CourseShowTest extends \Codeception\Test\Unit
     protected function _before()
     {
         \DBManager::getInstance()->setConnection('studip', $this->getModule('\\Helper\\StudipDb')->dbh);
+        //Initialize $SEM_TYPE and $SEM_CLASS arrays
+        $GLOBALS['SEM_CLASS'] = SemClass::getClasses();
+        $GLOBALS['SEM_TYPE'] = SemType::getTypes();
     }
 
     protected function _after()

tests/jsonapi/CoursesByUserTest.php

@@ -13,6 +13,9 @@ class CoursesByUserTest extends \Codeception\Test\Unit
     protected function _before()
     {
         \DBManager::getInstance()->setConnection('studip', $this->getModule('\\Helper\\StudipDb')->dbh);
+        //Initialize $SEM_TYPE and $SEM_CLASS arrays
+        $GLOBALS['SEM_CLASS'] = SemClass::getClasses();
+        $GLOBALS['SEM_TYPE'] = SemType::getTypes();
     }
 
     protected function _after()