def METHOD_NAME(prev_results, src_root, testing=False):
    # If there is no history of success, prev run could not have succeeded and vice versa for failures
    if prev_results[0] is None:
        return False
    elif prev_results[1] is None:
        return True
    else:
        if not testing:
            stat, out, err = run_cmd(
                "git merge-base --is-ancestor {}".format(" ".join(prev_results)),
                from_dir=src_root,
            )
            expect(
                stat in [0, 1],
                "Unexpected status from ancestor check:\n{}\n{}".format(out, err),
            )
        else:
            # Hack for testing
            stat = 0 if prev_results[0] < prev_results[1] else 1
        # stat == 0 tells us that pass is older than fail, so we must have failed, otherwise we passed
        return stat != 0