Re: Merge-base alias for git vc-diff

[joaotavora@gmail.com (João Távora)]

Stefan Monnier <monnier@IRO.UMontreal.CA> writes:

> FWIW, my minibuffer has 1 line and can't grow because it's in
> a minibuffer-only frame.

Kinky :) I don't think a rigid minibuffer is a great idea, but scratch
the multi-line minibuffer approach, just add a C-h shortcut that
displays some contextual help like `save-some-buffers'.

Or add some hint to the beginning of the line, there's plenty of space.

Here's two other ideas:

1. Isn't merge-base suitable for a toggle switch?  Could sth like
   vc-git-prefer-merge-base be useful?  Maybe I'd set that to t, and it
   shows nicely in a checkbox in the VC menu for discoverability.  But I
   like the next idea better.

2. A diff is always a comparison of two revisions, right?  For vc-dir,
   isn't a UI like query-replace's suitable here?  You know, that thing
   where you type the pattern and the replacement interactively in the
   same minibuffer prompt, separated by the arrow.  You can M-p, C-r,
   etc, flawlessly. I really like that UI, it's really intuitive (kudos
   to whoever participated, btw).
    
   So here, instead of pattern and replacement, two revisions.  All one
   would need, apparently, is to turn the arrow into a ".." and make it
   toggleable to "..." with say, C-M-y.  I think it would simplify the
   completion problem: on both sides of the ".." or "..." you just
   complete a revision using whatever system we presumably already have
   in place for that.

João