[pypy-issue] Issue #2544: str.casefold is wrong for some codepoints (Cherokee) (pypy/pypy)

[Ben Longbons]

New issue 2544: str.casefold is wrong for some codepoints (Cherokee)
https://bitbucket.org/pypy/pypy/issues/2544/strcasefold-is-wrong-for-some-codepoints

Ben Longbons:

Under python, '\uab70' correctly casefolds to '\u13a0'.

Under pypy, it does not.

Curiously, .lower() and .upper() work correctly on pypy.

Note that Cherokee casefolds to upper rather than lower, since uppercase were added first and casefolding is stable.