Removed request header "Content-Type" from the preferred format guessing mechanism

Author: yceruto

Request.php

@@ -1586,20 +1586,17 @@ public function isNoCache()
      */
     public function getPreferredFormat(?string $default = 'html'): ?string
     {
-        if (null !== $this->preferredFormat) {
+        if (null !== $this->preferredFormat || null !== $this->preferredFormat = $this->getRequestFormat(null)) {
             return $this->preferredFormat;
         }
 
-        $preferredFormat = null;
-        foreach ($this->getAcceptableContentTypes() as $contentType) {
-            if ($preferredFormat = $this->getFormat($contentType)) {
-                break;
+        foreach ($this->getAcceptableContentTypes() as $mimeType) {
+            if ($this->preferredFormat = $this->getFormat($mimeType)) {
+                return $this->preferredFormat;
             }
         }
 
-        $this->preferredFormat = $this->getRequestFormat($preferredFormat ?: $this->getContentType());
-
-        return $this->preferredFormat ?: $default;
+        return $default;
     }
 
     /**

Tests/RequestTest.php

@@ -408,12 +408,10 @@ public function testGetPreferredFormat()
 
         $request->setRequestFormat('atom');
         $request->headers->set('Accept', 'application/ld+json');
-        $request->headers->set('Content-Type', 'application/merge-patch+json');
         $this->assertSame('atom', $request->getPreferredFormat());
 
         $request = new Request();
         $request->headers->set('Accept', 'application/xml');
-        $request->headers->set('Content-Type', 'application/json');
         $this->assertSame('xml', $request->getPreferredFormat());
 
         $request = new Request();