How to use the discover.DiscoveringTestLoader function in discover

from extras import safe_hasattr

from testtools import TextTestResult
from testtools.compat import classtypes, istext, unicode_output_stream
from testtools.testsuite import filter_by_ids, iterate_tests, sorted_tests


defaultTestLoader = unittest.defaultTestLoader
defaultTestLoaderCls = unittest.TestLoader

if getattr(defaultTestLoader, 'discover', None) is None:
    try:
        import discover
        defaultTestLoader = discover.DiscoveringTestLoader()
        defaultTestLoaderCls = discover.DiscoveringTestLoader
        have_discover = True
    except ImportError:
        have_discover = False
else:
    have_discover = True


def list_test(test):
    """Return the test ids that would be run if test() was run.

    When things fail to import they can be represented as well, though
    we use an ugly hack (see http://bugs.python.org/issue19746 for details)
    to determine that. The difference matters because if a user is
    filtering tests to run on the returned ids, a failed import can reduce
    the visible tests but it can be impossible to tell that the selected
    test would have been one of the imported ones.

import sys

from extras import safe_hasattr

from testtools import TextTestResult
from testtools.compat import classtypes, istext, unicode_output_stream
from testtools.testsuite import filter_by_ids, iterate_tests, sorted_tests


defaultTestLoader = unittest.defaultTestLoader
defaultTestLoaderCls = unittest.TestLoader

if getattr(defaultTestLoader, 'discover', None) is None:
    try:
        import discover
        defaultTestLoader = discover.DiscoveringTestLoader()
        defaultTestLoaderCls = discover.DiscoveringTestLoader
        have_discover = True
    except ImportError:
        have_discover = False
else:
    have_discover = True


def list_test(test):
    """Return the test ids that would be run if test() was run.

    When things fail to import they can be represented as well, though
    we use an ugly hack (see http://bugs.python.org/issue19746 for details)
    to determine that. The difference matters because if a user is
    filtering tests to run on the returned ids, a failed import can reduce
    the visible tests but it can be impossible to tell that the selected

import os
import unittest
import sys

from testtools import TextTestResult
from testtools.compat import classtypes, istext, unicode_output_stream
from testtools.testsuite import iterate_tests, sorted_tests


defaultTestLoader = unittest.defaultTestLoader
defaultTestLoaderCls = unittest.TestLoader

if getattr(defaultTestLoader, 'discover', None) is None:
    try:
        import discover
        defaultTestLoader = discover.DiscoveringTestLoader()
        defaultTestLoaderCls = discover.DiscoveringTestLoader
        have_discover = True
    except ImportError:
        have_discover = False
else:
    have_discover = True


class TestToolsTestRunner(object):
    """ A thunk object to support unittest.TestProgram."""

    def __init__(self, verbosity=None, failfast=None, buffer=None):
        """Create a TestToolsTestRunner.

        :param verbosity: Ignored.
        :param failfast: Stop running tests at the first failure.

import unittest
import sys

from testtools import TextTestResult
from testtools.compat import classtypes, istext, unicode_output_stream
from testtools.testsuite import iterate_tests, sorted_tests


defaultTestLoader = unittest.defaultTestLoader
defaultTestLoaderCls = unittest.TestLoader

if getattr(defaultTestLoader, 'discover', None) is None:
    try:
        import discover
        defaultTestLoader = discover.DiscoveringTestLoader()
        defaultTestLoaderCls = discover.DiscoveringTestLoader
        have_discover = True
    except ImportError:
        have_discover = False
else:
    have_discover = True


class TestToolsTestRunner(object):
    """ A thunk object to support unittest.TestProgram."""

    def __init__(self, verbosity=None, failfast=None, buffer=None):
        """Create a TestToolsTestRunner.

        :param verbosity: Ignored.
        :param failfast: Stop running tests at the first failure.
        :param buffer: Ignored.

def get_tests():
    start_dir = os.path.dirname(__file__)
    test_loader = DiscoveringTestLoader()
    return test_loader.discover(start_dir, pattern="*.py")

def main(argv=None, testRunner=None, testLoader=None, exit=True, verbosity=1):
    if testLoader is None:
        testLoader = DiscoveringTestLoader
    if testRunner is None:
        testRunner = unittest.TextTestRunner
    if argv is None:
        argv = sys.argv[1:]

    tests, verbosity = _do_discovery(argv, verbosity, testLoader)
    return _run_tests(tests, testRunner, verbosity, exit)

except TypeError:
        yield test_suite_or_case
    else:
        for test in suite:
            for subtest in iterate_tests(test):
                yield subtest


defaultTestLoader = unittest.defaultTestLoader
defaultTestLoaderCls = unittest.TestLoader

if getattr(defaultTestLoader, 'discover', None) is None:
    try:
        import discover
        defaultTestLoader = discover.DiscoveringTestLoader()
        defaultTestLoaderCls = discover.DiscoveringTestLoader
        have_discover = True
    except ImportError:
        have_discover = False
else:
    have_discover = True


####################
# Taken from python 2.7 and slightly modified for compatibility with
# older versions. Delete when 2.7 is the oldest supported version.
# Modifications:
#  - Use have_discover to raise an error if the user tries to use
#    discovery on an old version and doesn't have discover installed.
#  - If --catch is given check that installHandler is available, as
#    it won't be on old python versions.
#  - print calls have been been made single-source python3 compatibile.

suite = iter(test_suite_or_case)
    except TypeError:
        yield test_suite_or_case
    else:
        for test in suite:
            for subtest in iterate_tests(test):
                yield subtest


defaultTestLoader = unittest.defaultTestLoader
defaultTestLoaderCls = unittest.TestLoader

if getattr(defaultTestLoader, 'discover', None) is None:
    try:
        import discover
        defaultTestLoader = discover.DiscoveringTestLoader()
        defaultTestLoaderCls = discover.DiscoveringTestLoader
        have_discover = True
    except ImportError:
        have_discover = False
else:
    have_discover = True


####################
# Taken from python 2.7 and slightly modified for compatibility with
# older versions. Delete when 2.7 is the oldest supported version.
# Modifications:
#  - Use have_discover to raise an error if the user tries to use
#    discovery on an old version and doesn't have discover installed.
#  - If --catch is given check that installHandler is available, as
#    it won't be on old python versions.