Instead of explicitly enumerate test classes for run_unittest()
use the unittest ability to discover tests. This also makes these
tests discoverable and runnable with unittest.
load_tests() can be used for dynamic generating tests and adding
doctests. setUpModule(), tearDownModule() and addModuleCleanup()
can be used for running code before and after all module tests.
When running test_bdb.py as a script, `import test_module` would be
importing the existing Lib/test/test_modules.py instead of the
tempcwd/test_module.py module which was dynamically created by
test_bdb.py itself.
Historically, -m added the empty string as sys.path
zero, meaning it resolved imports against the current
working directory, the same way -c and the interactive
prompt do.
This changes the sys.path initialisation to add the
*starting* working directory as sys.path[0] instead,
such that changes to the working directory while the
program is running will have no effect on imports
when using the -m switch.
Serhiy Storchaka
Irit Katriel
Inada Naoki
Hai Shi
Anthony Sottile
Alex H
Steve Dower
Nick Coghlan
xdegaye