Send HTTP status code 431 is request header is too large

Author: clue

src/Server.php

@@ -90,7 +90,7 @@ public function handleConnection(ConnectionInterface $conn)
 
             $that->writeError(
                 $conn,
-                400
+                ($e instanceof \OverflowException) ? 431 : 400
             );
         });
     }

tests/ServerTest.php

@@ -202,21 +202,37 @@ function ($data) use (&$buffer) {
         $this->assertContains("\r\nX-Powered-By: React/alpha\r\n", $buffer);
     }
 
-    public function testParserErrorEmitted()
+    public function testRequestOverflowWillEmitErrorAndSendErrorResponse()
     {
         $error = null;
         $server = new Server($this->socket);
         $server->on('error', function ($message) use (&$error) {
             $error = $message;
         });
 
+        $buffer = '';
+
+        $this->connection
+            ->expects($this->any())
+            ->method('write')
+            ->will(
+                $this->returnCallback(
+                    function ($data) use (&$buffer) {
+                        $buffer .= $data;
+                    }
+                )
+            );
+
         $this->socket->emit('connection', array($this->connection));
 
         $data = "GET / HTTP/1.1\r\nHost: example.com\r\nConnection: close\r\nX-DATA: ";
         $data .= str_repeat('A', 4097 - strlen($data)) . "\r\n\r\n";
         $this->connection->emit('data', array($data));
 
         $this->assertInstanceOf('OverflowException', $error);
+
+        $this->assertContains("HTTP/1.1 431 Request Header Fields Too Large\r\n", $buffer);
+        $this->assertContains("\r\n\r\nError 431: Request Header Fields Too Large", $buffer);
     }
 
     public function testRequestInvalidWillEmitErrorAndSendErrorResponse()