[2.7] closes bpo-8450: a better error message when http status line isn't received (GH-2825)

When the server has closed the connection before sending a status-line,
the client's error message should have a more descriptive error message

https://bugs.python.org/issue8450


https://bugs.python.org/issue8450

Lib/httplib.py

@@ -399,7 +399,7 @@ class HTTPResponse:
         if not line:
             # Presumably, the server closed the connection before
             # sending a valid response.
-            raise BadStatusLine(line)
+            raise BadStatusLine("No status line received - the server has closed the connection")
         try:
             [version, status, reason] = line.split(None, 2)
         except ValueError: