dirstate: force _checkexec to return a bool
posix.checkexec can return True, False, or None. The rust status
implementation expects a boolean, so make sure _checkexec returns a boolean.
Differential Revision: https://phab.mercurial-scm.org/D8432
To run the tests, do:
cd tests/
python run-tests.py
See https://mercurial-scm.org/wiki/WritingTests for
more information on writing tests.