annotate tests/test-mdiff.py @ 51721:ed28085827ec

typing: explicitly type some `mercurial.util` eol code to avoid @overload

Unlike the previous commit, this makes a material difference in the generated
stub file- the `pycompat.identity()` aliases generated an @overload like this:

    @overload
    def fromnativeeol(a: _T0) -> _T0: ...

... which might fail to detect a bad argument, like str.  This drops the
@overload for the 3 related methods, so there's a single definition for each.

The `typelib.BinaryIO_Proxy` is used for subclassing (the same as was done in
8147abc05794), so that it is a `BinaryIO` type during type checking, but still
inherits `object` at runtime.  That way, we don't need to implement unused
abstract methods.

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__)