Deprecate null $format argument to Request::getFormat() and ::setFormat().

longwave · longwave · commit 0ea77d7cea0c · 2025-11-01T16:45:43.000Z
diff --git a/UPGRADE-7.4.md b/UPGRADE-7.4.md
@@ -96,6 +96,7 @@ HttpFoundation
  * Deprecate using `Request::sendHeaders()` after headers have already been sent; use a `StreamedResponse` instead
  * Deprecate method `Request::get()`, use properties `->attributes`, `query` or `request` directly instead
  * Deprecate HTTP method override for methods GET, HEAD, CONNECT and TRACE; it will be ignored in Symfony 8.0
+ * Deprecate null `$format` argument to `Request::getFormat()` and `Request::setFormat()`
 
 HttpKernel
 ----------
diff --git a/src/Symfony/Component/HttpFoundation/Request.php b/src/Symfony/Component/HttpFoundation/Request.php
@@ -1311,11 +1311,15 @@ public static function getMimeTypes(string $format): array
      *      - return the MIME subtype (without "x-" prefix), provided it does not
      *        contain a "+" (e.g. "application/x-yaml" → "yaml", "text/csv" → "csv").
      *
-     * @param string|null $mimeType        The mime type to check
-     * @param bool        $subtypeFallback Whether to fall back to the subtype if no exact match is found
+     * @param string $mimeType        The mime type to check
+     * @param bool   $subtypeFallback Whether to fall back to the subtype if no exact match is found
      */
     public function getFormat(?string $mimeType/* , bool $subtypeFallback = false */): ?string
     {
+        if (null === $mimeType) {
+            trigger_deprecation('symfony/http-foundation', '7.4', 'Passing "null" as the first argument of "%s()" is deprecated. The argument will be non-nullable in Symfony 8.0.', __METHOD__);
+        }
+
         $subtypeFallback = 2 <= \func_num_args() ? func_get_arg(1) : false;
         $canonicalMimeType = null;
         if ($mimeType && false !== $pos = strpos($mimeType, ';')) {
@@ -1369,6 +1373,7 @@ public function getFormat(?string $mimeType/* , bool $subtypeFallback = false */
     /**
      * Associates a format with mime types.
      *
+     * @param string          $format    The format to set
      * @param string|string[] $mimeTypes The associated mime types (the preferred one must be the first as it will be used as the content type)
      */
     public function setFormat(?string $format, string|array $mimeTypes): void
@@ -1377,6 +1382,10 @@ public function setFormat(?string $format, string|array $mimeTypes): void
             static::initializeFormats();
         }
 
+        if (null === $format) {
+            trigger_deprecation('symfony/http-foundation', '7.4', 'Passing "null" as the first argument of "%s()" is deprecated. The argument will be non-nullable in Symfony 8.0.', __METHOD__);
+        }
+
         static::$formats[$format ?? ''] = (array) $mimeTypes;
     }
 
