import os

import sys

import unittest

def main(modulename):

    '''run the tests found in module, printing nothing when all tests pass'''

    module = sys.modules[modulename]

    suite = unittest.defaultTestLoader.loadTestsFromModule(module)

    results = unittest.TestResult()

    suite.run(results)

    if results.errors or results.failures:

        for tc, exc in results.errors:

            print('ERROR:', tc)

            print()

            sys.stdout.write(exc)

        for tc, exc in results.failures:

            print('FAIL:', tc)

            print()

            sys.stdout.write(exc)

        sys.exit(1)

if os.environ.get('SILENT_BE_NOISY'):

    main = unittest.main