tests/test-mdiff.py

tests: add a module that can perform the equivalent of `SIGKILL` on any OS

I started with this being Windows specific, but let's push all of the decision
making into this function so that it can just be called by the tests.  The
tradeoff is that this is very specific to sending `SIGKILL`- since
`signal.SIGKILL` doesn't exist on Windows, the desired signal can't be passed
from the caller.  Maybe there's a way, but let's wait until there's a need.

We don't use `killdaemons.py` unconditionally because it starts with a more
graceful `SIGTERM` on posix.

import unittest

from mercurial import mdiff


class splitnewlinesTests(unittest.TestCase):
    def test_splitnewlines(self):
        cases = {
            b'a\nb\nc\n': [b'a\n', b'b\n', b'c\n'],
            b'a\nb\nc': [b'a\n', b'b\n', b'c'],
            b'a\nb\nc\n\n': [b'a\n', b'b\n', b'c\n', b'\n'],
            b'': [],
            b'abcabc': [b'abcabc'],
        }
        for inp, want in cases.items():
            self.assertEqual(mdiff.splitnewlines(inp), want)


if __name__ == '__main__':
    import silenttestrunner

    silenttestrunner.main(__name__)