fixes #3781

Closes #3781

Merge request studip/studip!2655

app/controllers/course/lti.php

@@ -295,7 +295,7 @@ class Course_LtiController extends StudipController
             $lti_data->title = (string) $item['title'];
             $lti_data->description = Studip\Markup::purifyHtml(Studip\Markup::markAsHtml($item['text']));
             $lti_data->tool_id = $tool_id;
-            $lti_data->launch_url = (string) $item['url'];
+            $lti_data->launch_url = (string) ($item['url'] ?? '');
             $options = [];
             if (is_array($item['custom'])) {
                 $custom_parameters = '';

app/controllers/registration.php

@@ -133,8 +133,6 @@ class RegistrationController extends AuthenticatedController
                 $GLOBALS['auth']->auth['auth_plugin']  = $new_user['auth_plugin'];
                 $GLOBALS['auth']->auth_set_user_settings($new_user->user_id);
                 $GLOBALS['auth']->auth['uid'] = $new_user['user_id'];
-                $GLOBALS['auth']->auth['exp'] = time() + (60 * $GLOBALS['auth']->lifetime);
-                $GLOBALS['auth']->auth['refresh'] = time() + (60 * $GLOBALS['auth']->refresh);
 
                 Seminar_Register_Auth::sendValidationMail($new_user);
 

lib/classes/LtiLink.php

@@ -208,7 +208,7 @@ class LtiLink
     {
         $name = strtolower(preg_replace('/\W/', '_', $name));
         $value = preg_replace_callback('/\$([\w.]*\w)/', function($matches) {
-            return $this->variables[$matches[1]] ?: $matches[0];
+            return $this->variables[$matches[1]] ?? $matches[0];
         }, $value);
 
         $this->addLaunchParameter('custom_' . $name, $value);

lib/classes/forms/Form.php

@@ -527,7 +527,10 @@ class Form extends Part
             return function ($value) use ($context, $input) {
                 if ($context && !$value && $value !== null) {
                     $metadata = $context->getTableMetadata();
-                    if ($metadata['fields'][$input->getName()]['null'] === 'YES') {
+                    if (
+                        isset($metadata['fields'][$input->getName()]['null'])
+                        && $metadata['fields'][$input->getName()]['null'] === 'YES'
+                    ) {
                         //sets the value to null if this is a feasible db value for this field:
                         $value = null;
                     }

vendor/email_message/smtp_message.php

@@ -699,7 +699,7 @@ class smtp_message_class extends email_message_class
 					$message_id_set=1;
 					break;
 			}
-			if(strcmp($error,""))
+			if(strcmp($error ?? null,""))
 				return($this->ResetConnection($error));
 			if(strtolower($header_name)=="bcc")
 				continue;