bug symfony#28562 [HttpFoundation] fix hidding warnings from session handlers (nicolas-grekas)

This PR was merged into the 3.4 branch.

Discussion
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[HttpFoundation] fix hidding warnings from session handlers

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | symfony#28467
| License       | MIT
| Doc PR        | -

The current logic is too greedy.

Commits
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f405b4d [HttpFoundation] fix hidding warnings from session handlers

Author: fabpot

src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php

@@ -230,29 +230,22 @@ public function save()
             unset($_SESSION[$key]);
         }
 
-        // Register custom error handler to catch a possible failure warning during session write
-        set_error_handler(function ($errno, $errstr, $errfile, $errline) {
-            throw new \ErrorException($errstr, $errno, E_WARNING, $errfile, $errline);
-        }, E_WARNING);
+        // Register error handler to add information about the current save handler
+        $previousHandler = set_error_handler(function ($type, $msg, $file, $line) use (&$previousHandler) {
+            if (E_WARNING === $type && 0 === strpos($msg, 'session_write_close():')) {
+                $handler = $this->saveHandler instanceof SessionHandlerProxy ? $this->saveHandler->getHandler() : $this->saveHandler;
+                $msg = sprintf('session_write_close(): Failed to write session data with "%s" handler', \get_class($handler));
+            }
+
+            return $previousHandler ? $previousHandler($type, $msg, $file, $line) : false;
+        });
 
         try {
-            $e = null;
             session_write_close();
-        } catch (\ErrorException $e) {
         } finally {
             restore_error_handler();
             $_SESSION = $session;
         }
-        if (null !== $e) {
-            // The default PHP error message is not very helpful, as it does not give any information on the current save handler.
-            // Therefore, we catch this error and trigger a warning with a better error message
-            $handler = $this->getSaveHandler();
-            if ($handler instanceof SessionHandlerProxy) {
-                $handler = $handler->getHandler();
-            }
-
-            trigger_error(sprintf('session_write_close(): Failed to write session data with %s handler', \get_class($handler)), E_USER_WARNING);
-        }
 
         $this->closed = true;
         $this->started = false;