Fix empty streaming request body, omit Transfer-Encoding: chunked

src/Io/Sender.php

@@ -90,7 +90,7 @@ public function send(RequestInterface $request)
         } elseif ($size === 0 && \in_array($request->getMethod(), array('POST', 'PUT', 'PATCH'))) {
             // only assign a "Content-Length: 0" request header if the body is expected for certain methods
             $request = $request->withHeader('Content-Length', '0');
-        } elseif ($body instanceof ReadableStreamInterface && $body->isReadable() && !$request->hasHeader('Content-Length')) {
+        } elseif ($body instanceof ReadableStreamInterface && $size !== 0 && $body->isReadable() && !$request->hasHeader('Content-Length')) {
             // use "Transfer-Encoding: chunked" when this is a streaming body and body size is unknown
             $request = $request->withHeader('Transfer-Encoding', 'chunked');
         } else {

tests/Io/SenderTest.php

@@ -5,6 +5,7 @@
 use Psr\Http\Message\RequestInterface;
 use React\Http\Client\Client as HttpClient;
 use React\Http\Io\ClientConnectionManager;
+use React\Http\Io\EmptyBodyStream;
 use React\Http\Io\ReadableBodyStream;
 use React\Http\Io\Sender;
 use React\Http\Message\Request;
@@ -264,6 +265,21 @@ public function testSendGetWillNotPassContentLengthHeaderForEmptyRequestBody()
         $sender->send($request);
     }
 
+    public function testSendGetWithEmptyBodyStreamWillNotPassContentLengthOrTransferEncodingHeader()
+    {
+        $client = $this->getMockBuilder('React\Http\Client\Client')->disableOriginalConstructor()->getMock();
+        $client->expects($this->once())->method('request')->with($this->callback(function (RequestInterface $request) {
+            return !$request->hasHeader('Content-Length') && !$request->hasHeader('Transfer-Encoding');
+        }))->willReturn($this->getMockBuilder('React\Http\Io\ClientRequestStream')->disableOriginalConstructor()->getMock());
+
+        $sender = new Sender($client);
+
+        $body = new EmptyBodyStream();
+        $request = new Request('GET', 'http://www.google.com/', array(), $body);
+
+        $sender->send($request);
+    }
+
     public function testSendCustomMethodWillNotPassContentLengthHeaderForEmptyRequestBody()
     {
         $client = $this->getMockBuilder('React\Http\Client\Client')->disableOriginalConstructor()->getMock();