All of the other methods in mailbox that create message objects take care to
close the file descriptors they use, so it seems to make sense to have
__getitem__ do so as well.

Patch by Filip Gruszczyński.

- Move a tearDown method right after setUp
- Use assertRaises instead of reinventing it
- Skip a test instead of commenting it out, as a reminder

Victor Stinner diagnosed on #12167 that some reference leaks came from
util._path_created, a set used for caching; there are two tests that
cause additions to this set, so now they clear it in tearDown, avoiding
17 refleaks.  (My tests show that it’s necessary to clear the set in
only one test, clearing it in both does not stop more refleaks, but
there’s no harm in doing it.)

Fix os.fchown() and os.open()

Remove also trailing spaces and replace tabs by spaces.

Fix os.fchown() and os.open()

Remove also trailing spaces and replace tabs by spaces.

AbstractHTTPHandler.do_open() of urllib.request closes the HTTP connection if
its getresponse() method fails with a socket error. Patch written by Ezio
Melotti.

AbstractHTTPHandler.do_open() of urllib.request closes the HTTP connection if
its getresponse() method fails with a socket error. Patch written by Ezio
Melotti.

It is not possible to unload a module written in C, so use a subprocess to run
the tests on the module compiled by test_build_ext(). Using a subprocess, we
don't have to unload the module, save/restore sys.path, and the test can be run
more than once.

This commit fixes also an access error on rmtree() on Windows: because the
module was not really unloaded, it was not possible to remove the temporary
directory (it is not possible to remove a directory on Windows if it still
contains an open file).

packaging.tests.support.TempdirManager: rmtree() fails on Windows if there are
still open files in the directory.

- Use different Metadata objects to write and read a PKG-INFO (METADATA)
  file, to make sure the tested values come from the file

- No need to restore methods on an instance after monkey-patching them:
  the methods are still the same on the class

- Harmonize dedent calls

multiprocessing: Process._bootstrap() keeps a reference to the old process to
delay its finalization until after _run_after_forkers() as been executed. This
change should fix a crash on Mac OS X Tiger when a lock is released after a
fork.

Patch written by Charles-François Nataliv and Antoine Pitrou.

multiprocessing: Process._bootstrap() keeps a reference to the old process to
delay its finalization until after _run_after_forkers() as been executed. This
change should fix a crash on Mac OS X Tiger when a lock is released after a
fork.

Patch written by Charles-François Nataliv and Antoine Pitrou.

packaging.tests.support.TempdirManager: removing the current directory is not
allowed on Windows or Solaris. Store the current directory and restore it
before removing the temporary directory (which is used as the working directory
during the tests).

The two public functions in database default to sys.path if the given
*paths* argument is None; the private functions don’t have default
values for their arguments anymore, which is fine as the public
functions that call them pass their arguments down.  Likewise in
install, the functions will pass down their *paths* arguments down to
database functions.

A one-line unneeded function in install was removed instead of being
changed, and the few remaining tests that used brute-force restoration
of sys.path have been cleaned up to use sys.path.remove.

Now only the compatibility layer (in create, util and install) talk
about setup.py.

Don't modify mutable default arguments...

After 1a3e8db28d49, Windows XP could not os.stat at all due to raising
immediately when GetFinalPathNameByHandle wasn't available (pre-Vista).
The proper behavior in that situation is to just not attempt a traversal
rather than outright rejecting.

This change additionally handles a failed malloc by setting the error code
and returning false.

Patch by Hirokazu Yamamoto.