help for the re-merge case when overwriting tags is the default

[Christian Ehrhardt ]

Hi,
as discussed to log the idea of our talk.
When you have a re-merge tags like new/debian will change - please consider detecting the case and make it work for the most common case.

[Nish Aravamudan (nacc)]

Can you give some notion of the algorithm you are thinking of here?

[Christian Ehrhardt  (paelzer)]

I hope I remember the right case here, I think this was about not needing --force for the common cases.
One of these common cases is
1. doing a merge creating new/debian (and others)
2. a cycle later you'd do "git fetch --all"
3. run "usd merge" to set the tags to the right spot
   This needs --force today, but will become a common case.

In some sens we don't want users to use --force by default.

I haven't tried for a long time, it might even work today?

Pseudo Code:
1. if creating the three tags of "usd merge" check if they are already around
2. if so you know that those will collide
3. prompt to the user of what you found and provide a "<bla>, do you want to set force Y/N"?

If your --force today forces more than those three you might want a softer --force-tags and set that on behalf of step #3 being answered with yes. Also users enabling --force-tags by default is only half as bad as doing so with a more far reaching --force.