tests/mockmakedate.py

tests: use simple mock smtp server instead of deprecated asyncore smtpd

test-patchbomb-tls.t would fail with:
  .../hg/tests/dummysmtpd.py:6: DeprecationWarning: The asyncore module is deprecated and will be removed in Python 3.12. The recommended replacement is asyncio
    import asyncore
  .../hg/tests/dummysmtpd.py:8: DeprecationWarning: The smtpd module is deprecated and unmaintained and will be removed in Python 3.12.  Please see aiosmtpd (https://aiosmtpd.readthedocs.io/) for the recommended replacement.
    import smtpd

The recommended migration path to the standalone asiosmtpd would be overkill.

The tests do not need a full smtp server - we can just use a very simple mock
hack to preserve the existing test coverage.

# mock out util.makedate() to supply testable values


import os

from mercurial import pycompat
from mercurial.utils import dateutil


def mockmakedate():
    filename = os.path.join(os.environ['TESTTMP'], 'testtime')
    try:
        with open(filename, 'rb') as timef:
            time = float(timef.read()) + 1
    except IOError:
        time = 0.0
    with open(filename, 'wb') as timef:
        timef.write(pycompat.bytestr(time))
    return (time, 0)


dateutil.makedate = mockmakedate