Re: [PATCH 09/14] revert: Don't create invalid replay_opts in parse_args

> The "--ff" command-line option cannot be used with four other
> command-line options.  However, when these options are specified with
> "--ff" on the command-line, parse_args will still parse these
> incompatible options into a replay_opts structure for use by the rest
> of the program.  Although pick_commits checks the validity of the
> replay_opts strucutre before before starting its operation, this is
> inelegant design; pick_commits is currently the gatekeeper to the
> cherry-pick machinery, but this will change in future.  To futureproof
> the code and catch these errors in one place, make sure that an
> invalid replay_opts structure is not created by parse_args in the
> first place.  Also ensure that regressions in maintaining this
> invariant are caught in the future by adding an assertion in
> pick_commits.