Fix several Psalm-issues

src/SimpleSAML/Module.php

@@ -420,7 +420,7 @@ class Module
      *
      * @param string      $id The string we should resolve.
      * @param string      $type The type of the class.
-     * @param string|null $subclass The class should be a subclass of this class. Optional.
+     * @param class-string|null $subclass The class should be a subclass of this class. Optional.
      *
      * @return string The classname.
      *

src/SimpleSAML/Session.php

@@ -262,7 +262,7 @@ class Session implements Utils\ClearableState
     /**
      * Retrieves the current session. Creates a new session if there's not one.
      *
-     * @return Session The current session.
+     * @return \SimpleSAML\Session The current session.
      * @throws \Exception When session couldn't be initialized and the session fallback is disabled by configuration.
      */
     public static function getSessionFromRequest(): Session

src/SimpleSAML/XHTML/Template.php

@@ -558,13 +558,15 @@ class Template extends Response
     /**
      * Send this template as a response.
      *
-     * @return \Symfony\Component\HttpFoundation\Response This response.
+     * @return static This response.
      * @throws \Exception if the template cannot be found.
      */
     public function send(): static
     {
         $this->content = $this->getContents();
-        return /** @scrutinizer ignore-type */parent::send();
+        parent::send();
+
+        return $this;
     }
 
 

src/SimpleSAML/XHTML/TemplateLoader.php

@@ -29,7 +29,7 @@ class TemplateLoader extends \Twig\Loader\FilesystemLoader
      *
      * @param string $name
      * @param bool $throw
-     * @return string|false|null
+     * @return string|null
      *
      * NOTE: cannot typehint due to upstream restrictions
      */

src/SimpleSAML/XML/Signer.php

@@ -182,6 +182,7 @@ class Signer
      * @param bool $full_path  Whether the filename found in the configuration contains the
      *                         full path to the private key or not. Default to false.
      * @throws \Exception
+     * @throws \Symfony\Component\HttpFoundation\File\Exception\FileException
      */
     public function loadCertificate(string $file, bool $full_path = false): void
     {
@@ -197,11 +198,7 @@ class Signer
         }
 
         $file = new File($certFile);
-        $cert = $file->getContent();
-        if ($cert === false) {
-            throw new Exception('Unable to read certificate file "' . $certFile . '".');
-        }
-        $this->certificate = $cert;
+        $this->certificate = $file->getContent();
     }