Function main

python/python3/tornado/testing.py:796–885

A simple test runner. This test runner is essentially equivalent to `unittest.main` from the standard library, but adds support for Tornado-style option parsing and log formatting. It is *not* necessary to use this `main` function to run tests using `AsyncTestCase`; these tests

(**kwargs: Any)

def main(**kwargs: Any) -> None:
    """A simple test runner.

    This test runner is essentially equivalent to `unittest.main` from
    the standard library, but adds support for Tornado-style option
    parsing and log formatting. It is *not* necessary to use this
    `main` function to run tests using `AsyncTestCase`; these tests
    are self-contained and can run with any test runner.

    The easiest way to run a test is via the command line::

        python -m tornado.testing tornado.test.web_test

    See the standard library ``unittest`` module for ways in which
    tests can be specified.

    Projects with many tests may wish to define a test script like
    ``tornado/test/runtests.py``.  This script should define a method
    ``all()`` which returns a test suite and then call
    `tornado.testing.main()`.  Note that even when a test script is
    used, the ``all()`` test suite may be overridden by naming a
    single test on the command line::

        # Runs all tests
        python -m tornado.test.runtests
        # Runs one test
        python -m tornado.test.runtests tornado.test.web_test

    Additional keyword arguments passed through to ``unittest.main()``.
    For example, use ``tornado.testing.main(verbosity=2)``
    to show many test details as they are run.
    See http://docs.python.org/library/unittest.html#unittest.main
    for full argument list.

    .. versionchanged:: 5.0

       This function produces no output of its own; only that produced
       by the `unittest` module (previously it would add a PASS or FAIL
       log message).
    """
    from tornado.options import define, options, parse_command_line

    define(
        "exception_on_interrupt",
        type=bool,
        default=True,
        help=(
            "If true (default), ctrl-c raises a KeyboardInterrupt "
            "exception.  This prints a stack trace but cannot interrupt "
            "certain operations.  If false, the process is more reliably "
            "killed, but does not print a stack trace."
        ),
    )

    # support the same options as unittest's command-line interface
    define("verbose", type=bool)
    define("quiet", type=bool)
    define("failfast", type=bool)