tests/test-mdiff.py

storageutil: extract filelog.cmp() to a standalone function

As part of implementing an alternate storage backend, I found myself
reimplementing this code.

With a little massaging, we can extract filelog.cmp() to a standalone
function.

As part of this, the call to revlog.cmp() was inlined (it is just a
2-line function).

I also tweaked some variable names to improve readability. I'll
further tweak names in a subsequent commit.

Differential Revision: https://phab.mercurial-scm.org/D4801

from __future__ import absolute_import
from __future__ import print_function

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__)