[PATCH 1 of 4 V2] obsolete: track node versions

[Durham Goode]

On 3/30/17 11:28 AM, Durham Goode wrote:
>
> 1. Never hide a commit during hg pull. Only hide commits when the user
> does an action (strip/rebase/amend/histedit/evolve)
>
> 2. Auto rebase uses "visible successors" instead of "latest successor"

To elaborate on how I see this obs cycle series affecting this proposal, 
I think the end result of this proposal is that obs versioning won't 
matter anymore.  Or at the very least versioning only becomes a rough 
heuristic to suggest to the user which visible successor is likely to be 
their desired auto rebase destination.

But, this series would be a fast way to introduce the concept of 
unhiding into core, which would let us start developing user experiences 
that benefit from unhiding, until we have truly separate hidden storage. 
So if we think my proposal is a good idea and where we want to be in the 
long run, I think we take this obscycle series, and don't worry about 
date being an imperfect heuristic since it won't matter in the long run. 
And we don't worry about the edge cases where it's unclear if X should 
be visible or Y, because in the future visibility will only ever be 
changed by explicit user action, and never by deducing it from obsmarker.