def test_explicitly_send_headers(self):
req = self.make_request('GET', '/')
resp = Response(req)
self.writer.drain.return_value = ()
buf = b''
def append(data):
nonlocal buf
buf += data
self.writer.write.side_effect = append
resp.send_headers()
self.loop.run_until_complete(resp.write_eof())
txt = buf.decode('utf8')
self.assertRegex(txt, 'HTTP/1.1 200 OK\r\nCONTENT-LENGTH: 0\r\n'
'CONNECTION: keep-alive\r\n'
'DATE: .+\r\nSERVER: .+\r\n\r\n')
