[PATCH 2 of 2 v2] rebase: add flag to require destination

[David Soria Parra]

On Tue, Mar 14, 2017 at 05:56:16PM -0700, Ryan McElroy wrote:
> # HG changeset patch
> # User Ryan McElroy <rmcelroy at fb.com>
> # Date 1489538624 25200
> #      Tue Mar 14 17:43:44 2017 -0700
> # Node ID 8d8b783803f43d5e2d86916c39e9554139752fe6
> # Parent  2dc26c57e60e7e7bf46a276e8a498a9746bd9271
> rebase: add flag to require destination
> 

This looks good to me. I was wondering if we want to provide separate knobs for
these commands which might lead to config overhead or provide more comprehensive
"ui" improvement knobs such as "commands.requiredest" to move people to a better
model in logical steps.

e.g. I am a user who likes a slightly enhanced user experience. ui.compat= is a
bit too much for me, but update destinations is a good idea. Do i have to find
all places where we use destinations to update or do I want to select a logical
step?

I personally think while fine granualar steps are nice, I'd probably lean
towards logical steps as it provides a more consistent behavior for users (e.g.
assume an extension Y that we don't know of can opt into using
"commands.requiredest", which at the moment it cannot unless it depends on
"commands.update.requiredest" which is missleading.