bug#23785: Emacs 25: 'Undo' overdoes things.

[Phillip Lord]

"Phillip Lord" <phillip.lord@russet.org.uk> writes:

> On Sat, June 18, 2016 8:52 pm, Stefan Monnier wrote:
>>> My concern is not with the behavior the proposed change intends to get
>>> us, the concern is with the unintended consequences of the change.  At
>>> this late stage, I'd like to keep the risk of unintended consequences to
>>> the minimum, unless we want this change so badly we agree to extend the
>>> pretesting by another month or two.
>>
>> Yes, that's the other side of the coin, indeed.
>
> So many possibilities!


So, final patch possibility -- this one, I think directly fixes the
problem -- it ensures that the changes in the buffer result in an
undoable change.

It's probably less efficient (cause the undo-list will be created, then
dumped), but is the most minimal change.

My suggestion: this patch goes to Emacs-25. And the previous patch
(which automatically adds an undo boundary to current-buffer regardless
of changes), goes to master.

Phil