Twisted 8.2.0 requires pywin32

[amaury]

On Windows, if pywin32 is not installed, it is impossible to import Twisted:

Python 2.6.1 (r261:69718, Feb 17 2009, 15:28:19) [MSC v.1400 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from twisted.internet import defer
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "c:\prod\python\lib\site-packages\twisted-8.2.0-py2.6-win32.egg\twisted\internet\defer.py", l
ine 17, in <module>
    from twisted.python import log, failure, lockfile
  File "c:\prod\python\lib\site-packages\twisted-8.2.0-py2.6-win32.egg\twisted\python\lockfile.py",
line 28, in <module>
    from win32api import OpenProcess
ImportError: No module named win32api

This is unfortunate for simple applications, which don't use the DeferredFilesystemLock. And this makes Twisted usage by pypy much harder...

I suggest to make this dependency optional. For example, if pywin32 cannot be imported, we could assume that the other process is still running. I attach a patch along this idea.

[christianmlong]

I reviewed the patch. It applied cleanly, and it fixed the Import error. I added some skips to twisted.test.test_lockfile.py. See attached patch for test_lockfile.py.

[amaury]

Is it possible to setup a buildbot to run tests with the following option?

    --without-module=pywintypes,win32api,win32file,win32pipe,win32process,win32com

[Jean-Paul Calderone]

We're pretty short on Windows slaves, unfortunately. :/ Setting up a new builder is pretty easy, but we don't have any place to put one right now.

[Jean-Paul Calderone]

Patches mostly look good. The unit tests accidentally cause skips on non-Windows platforms, though. I suppose they need to check something like twisted.python.runtime.platform.isWindows() before trying to do the imports.

[Jean-Paul Calderone]

Hmm, one further comment. I think the test suite needs to expand a little bit to exercise the new if kill is not None: check. It just needs to verify that when kill does end up as None, it doesn't end up being called and raising a TypeError.

[christianmlong]

Added some skips for cases when we are on windows, but pywin32 is not available

[Jean-Paul Calderone]

(In [26632]) Branching to 'skip-without-pywin32-3707'

[Jean-Paul Calderone]

(In [26633]) Apply patch from amaury and christian long

refs #3707

[Jean-Paul Calderone]

This looks good to me. I hope we can set up a builder to test this configuration soon. I think we could also improve our overall skip factoring. Seeing all the duplicates added at once, instead of one at a time over a long period of time, makes it obvious just how much duplication we have. I'm thinking that in the future we might have a twisted.test.skips (or something) which does all the detection and defines skips which can then be imported into test modules and set onto things.

[Jean-Paul Calderone]

(In [26634]) Merge skip-without-pywin32-3707

Author: amaury, christianmlong Reviewer: exarkun Fixes: #3707

Skip all the tests which require process support on Windows if pywin32 is not installed (and thus IReactorProcess won't work).

[amaury]

Thanks for the correction!

I think that the change description should mention somewhere that Twisted could not work at all if pywin32 is not installed.