bug#22295: viper-mode undo bug introduced between Nov 10 and Nov 14

[Phillip Lord]

Eli Zaretskii <eliz@gnu.org> writes:

> FWIW, I think this should go to emacs-25, since (a) the changes affect
> only viper-mode, and (b) users of that mode will be most unhappy
> without these changes.

Not quite true. I've changed simple.el.

The change is minimal, and just allows downstream developers to disable
the auto-undo boundary. However, if a developer does do this in a bad
way, then Emacs does produce pretty intrusive "this is probably a bug"
warnings.


> However, we should add comments to viper-cmd.el that document the
> special handling of 'undo' by viper-mode, and how that interacts with
> the core 'undo' functionalities.  We should also comment in simple.el
> that undo-auto-disable-boundaries is used by viper-mode, and document
> that variable in the ELisp manual.  Phillip, can you add these bits to
> the branch, please?


Oh, yeah, sorry forgot the manual. I updated most of the rest last
night. I think that the branch is ready, bar squashing.

Phil