Fixed consecutive calls for write_eof on Response

CHANGES.rst

@@ -6,6 +6,8 @@ Changes
 
 - Add doc for add_head, update doc for add_get. #1944
 
+- Fixed consecutive calls for `Response.write_eof`.
+
 - Retain method attributes (e.g. :code:`__doc__`) when registering synchronous
   handlers for resources. #1953
 

CONTRIBUTORS.txt

@@ -129,6 +129,7 @@ Pankaj Pandey
 Pau Freixes
 Paul Colomiets
 Paulus Schoutsen
+Pavel Kamaev
 Pawel Miech
 Philipp A.
 Rafael Viotti

aiohttp/web_response.py

@@ -563,6 +563,8 @@ def content_length(self, value):
 
     @asyncio.coroutine
     def write_eof(self):
+        if self._eof_sent:
+            return
         body = self._body
         if body is not None:
             if (self._req._method == hdrs.METH_HEAD or

tests/test_web_response.py

@@ -889,6 +889,20 @@ def test_send_set_cookie_header(buf, writer):
                     'Server: .+\r\n\r\n', txt)
 
 
+@asyncio.coroutine
+def test_consecutive_write_eof():
+    req = make_request('GET', '/')
+    data = b'data'
+    resp = Response(body=data)
+
+    yield from resp.prepare(req)
+    with mock.patch('aiohttp.web.StreamResponse.write_eof') as super_write_eof:
+        yield from resp.write_eof()
+        resp._eof_sent = True
+        yield from resp.write_eof()
+        super_write_eof.assert_called_once_with(data)
+
+
 def test_set_text_with_content_type():
     resp = Response()
     resp.content_type = "text/html"