[Python-Dev] RE: test_asynchat.py broken on Windows (original) (raw)

Tim Peters tim.one@home.com
Mon, 29 Oct 2001 20:37:49 -0500

[Jeremy Hylton]

I think there are at least three things wrong, depending on what you count as wrong.

I would have guessed five, if you were counting Windows too .

The test is hanging because it spawns a thread, which Python will prevent Python from exiting until the thread exits. The thread doesn't exit because it's waiting for input from the client. The client doesn't send it any input because of the exception.

thing wrong #1: It would probably make sense to change testasynchat.py to use a daemon thread so that it can't prevent the test suite from exiting.

I don't much care about this.

thing wrong #2: I don't think the ENONET being returned by connectex() makes any sense. My guess is that connectex() is (and always has been) broken on Windows. Could you apply this patch and see what happens: ...

Fixed the problem, so I checked it in. Thanks!

thing wrong #3: From the winsock documentation for connect(), it looks like there are more errors we should be catching in the test that includes EWOULDBLOCK and EALREADY. I don't think this would affect your test, though.

I'm not sure I parsed that as intended; asyncore.dispatcher.connect (in the traceback when test_asynchat failed) is already checking for EINPROGRESS, EALREADY, EWOULDBLOCK, 0 and EISCONN returns from connect_ex. But, for posterity, I will inscribe my socket programming knowledge in the period at the end of this sentence.

thing wrong #4: It doesn't look to me like the connect() call in testasynchat.py is guaranteed to succeed. It should succeed almost every time, but there's some small chance it will fail. Perhaps the test should be more robust about that.

FWIW, I've never seen it fail before.

That's four things, but I don't think the last thing is all that wrong.

Here's a fifth:

def main(): s = echo_server() s.start() time.sleep(1) # Give server time to initialize c = echo_client() ...

time.sleep()-is-not-a-synchronization-gimmick-ly y'rs - tim