Make stream() satisfy its v1.10 contract

In 1.10 through 1.10.2, `HTTPResponse.stream()` always called
`HTTPResponse.read()`.  This method catches all `HTTPException`
(including `httplib.IncompleteRead`), and re-raises them as
`ProtocolError`.

In 1.10.3 and 1.10.4, `HTTPResponse.stream()` may call
`HTTPResponse.read_chunked()` instead. This method may (via the
`_update_chunk_length()` helper method) raise `httplib.IncompleteRead`.
This exception will not be caught, and will be raised out of the call to
`HTTPResponse.stream()`.

Fix the contract of `HTTPResponse.stream()` by making
`HTTPResponse.read_chunked()` catch the same low-level exceptions that
`HTTPResponse.read()` catches. This is accomplished by refactoring this
try/except logic into a shared context manager.

Fixes #673.

1 files changed, 2 insertions, 2 deletions

diff --git a/test/test_response.py b/test/test_response.py
index 2e2be0ec..47d05213 100644
--- a/test/test_response.py
+++ b/test/test_response.py
@@ -7,7 +7,7 @@ try:
 except ImportError:
     import httplib
 from urllib3.response import HTTPResponse
-from urllib3.exceptions import DecodeError, ResponseNotChunked
+from urllib3.exceptions import DecodeError, ResponseNotChunked, ProtocolError
 
 
 from base64 import b64decode
@@ -487,7 +487,7 @@ class TestResponse(unittest.TestCase):
         r.chunked = True
         r.chunk_left = None
         resp = HTTPResponse(r, preload_content=False, headers={'transfer-encoding': 'chunked'})
-        self.assertRaises(httplib.IncompleteRead, next, resp.read_chunked())
+        self.assertRaises(ProtocolError, next, resp.read_chunked())
 
     def test_chunked_response_without_crlf_on_end(self):
         stream = [b"foo", b"bar", b"baz"]