- Warn-raise ImportWarning when importing would have picked up a directory
as package, if only it'd had an __init__.py. This swaps two tests (for
case-ness and __init__-ness), but case-test is not really more expensive,
and it's not in a speed-critical section.
- Test for the new warning by importing a common non-package directory on
sys.path: site-packages
- In regrtest.py, silence warnings generated by the build-environment
because Modules/ (which is added to sys.path for Setup-created modules)
has 'zlib' and '_ctypes' directories without __init__.py's.
added message attribute compared to the previous version of Exception. It is
also a new-style class, making all exceptions now new-style. KeyboardInterrupt
and SystemExit inherit from BaseException directly. String exceptions now
raise DeprecationWarning.
Applies patch 1104669, and closes bugs 1012952 and 518846.