def test_iadd(self, evt):
        rval = event.ReturnValue(append_events=[evt])
        rval2 = event.ReturnValue(eat=True, append_events=[evt])
        rset = event.ResultSet()

        rset += rval
        rset += rval2
        rset += None
        assert rset.eat
        assert rset.append_events == [evt, evt]
def get_revision(cls, location, rev=None):
        if rev is None:
            rev = 'HEAD'
        current_rev = cls.run_command(
            ['rev-parse', rev],
            show_stdout=False,
            stdout_only=True,
            cwd=location,
        )
        return current_rev.strip()