From 7d0a84d196d2a00c00804158bd3366a1b946dc84 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20L=C3=BCck?= <christian@lueck.tv>
Date: Sat, 27 Jan 2018 13:27:54 +0100
Subject: [PATCH] Fix ignoring invalid double Transfer-Encoding

---
 src/Response.php       | 34 +++++++++++++++++++++++++---------
 tests/ResponseTest.php | 31 +++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+), 9 deletions(-)

diff --git a/src/Response.php b/src/Response.php
index 6aa1f12..88605dd 100644
--- a/src/Response.php
+++ b/src/Response.php
@@ -31,17 +31,10 @@ public function __construct(ReadableStreamInterface $stream, $protocol, $version
         $this->code = $code;
         $this->reasonPhrase = $reasonPhrase;
         $this->headers = $headers;
-        $normalizedHeaders = array_change_key_case($headers, CASE_LOWER);
 
-        if (isset($normalizedHeaders['transfer-encoding']) && strtolower($normalizedHeaders['transfer-encoding']) === 'chunked') {
+        if (strtolower($this->getHeaderLine('Transfer-Encoding')) === 'chunked') {
             $this->stream = new ChunkedStreamDecoder($stream);
-
-            foreach ($this->headers as $key => $value) {
-                if (strcasecmp('transfer-encoding', $key) === 0) {
-                    unset($this->headers[$key]);
-                    break;
-                }
-            }
+            $this->removeHeader('Transfer-Encoding');
         }
 
         $this->stream->on('data', array($this, 'handleData'));
@@ -75,6 +68,29 @@ public function getHeaders()
         return $this->headers;
     }
 
+    private function removeHeader($name)
+    {
+        foreach ($this->headers as $key => $value) {
+            if (strcasecmp($name, $key) === 0) {
+                unset($this->headers[$key]);
+                break;
+            }
+        }
+    }
+
+    private function getHeader($name)
+    {
+        $name = strtolower($name);
+        $normalized = array_change_key_case($this->headers, CASE_LOWER);
+
+        return isset($normalized[$name]) ? (array)$normalized[$name] : array();
+    }
+
+    private function getHeaderLine($name)
+    {
+        return implode(', ' , $this->getHeader($name));
+    }
+
     /** @internal */
     public function handleData($data)
     {
diff --git a/tests/ResponseTest.php b/tests/ResponseTest.php
index 2bea171..d7ad6b8 100644
--- a/tests/ResponseTest.php
+++ b/tests/ResponseTest.php
@@ -129,5 +129,36 @@ public function chunkedEncodingResponse()
             $response->getHeaders()
         );
     }
+
+    /** @test */
+    public function doubleChunkedEncodingResponseWillBePassedAsIs()
+    {
+        $stream = new ThroughStream();
+        $response = new Response(
+            $stream,
+            'http',
+            '1.0',
+            '200',
+            'ok',
+            array(
+                'content-type' => 'text/plain',
+                'transfer-encoding' => array(
+                    'chunked',
+                    'chunked'
+                )
+            )
+        );
+
+        $this->assertSame(
+            array(
+                'content-type' => 'text/plain',
+                'transfer-encoding' => array(
+                    'chunked',
+                    'chunked'
+                )
+            ),
+            $response->getHeaders()
+        );
+    }
 }