[8.x] Make accept header comparison case-insensitive (#39413)

* Make accept header comparison case-insensitive

* Update comment and ref link

* Update InteractsWithContentTypes.php

Co-authored-by: Taylor Otwell <[email protected]>

Author: kunalray1993

src/Illuminate/Http/Concerns/InteractsWithContentTypes.php

@@ -35,7 +35,7 @@ public function wantsJson()
     {
         $acceptable = $this->getAcceptableContentTypes();
 
-        return isset($acceptable[0]) && Str::contains($acceptable[0], ['/json', '+json']);
+        return isset($acceptable[0]) && Str::contains(strtolower($acceptable[0]), ['/json', '+json']);
     }
 
     /**
@@ -60,6 +60,10 @@ public function accepts($contentTypes)
             }
 
             foreach ($types as $type) {
+                $accept = strtolower($accept);
+
+                $type = strtolower($type);
+
                 if ($this->matchesType($accept, $type) || $accept === strtok($type, '/').'/*') {
                     return true;
                 }
@@ -93,6 +97,10 @@ public function prefers($contentTypes)
                     $type = $mimeType;
                 }
 
+                $accept = strtolower($accept);
+
+                $type = strtolower($type);
+
                 if ($this->matchesType($type, $accept) || $accept === strtok($type, '/').'/*') {
                     return $contentType;
                 }

tests/Http/HttpRequestTest.php

@@ -1006,6 +1006,21 @@ public function testBadAcceptHeader()
         $this->assertFalse($request->accepts('text/html'));
     }
 
+    public function testCaseInsensitiveAcceptHeader()
+    {
+        $request = Request::create('/', 'GET', [], [], [], ['HTTP_ACCEPT' => 'APPLICATION/JSON']);
+        $this->assertTrue($request->accepts(['text/html', 'application/json']));
+
+        $request = Request::create('/', 'GET', [], [], [], ['HTTP_ACCEPT' => 'AppLiCaTion/JsOn']);
+        $this->assertTrue($request->accepts(['text/html', 'application/json']));
+
+        $request = Request::create('/', 'GET', [], [], [], ['HTTP_ACCEPT' => 'APPLICATION/*']);
+        $this->assertTrue($request->accepts(['text/html', 'application/json']));
+
+        $request = Request::create('/', 'GET', [], [], [], ['HTTP_ACCEPT' => 'APPLICATION/JSON']);
+        $this->assertTrue($request->expectsJson());
+    }
+
     public function testSessionMethod()
     {
         $this->expectException(RuntimeException::class);