Re: Collaborative conflict resolution feature request

On Mon, Jun 15, 2020 at 10:32 AM Chris Torek [off-list ref] wrote:

I've thought about this (some) myself in the past.  It seems to me that what
is needed is the ability to pass the complete unmerged state on.

A few further thoughts:

 * Given one or more saved merges and either a clean state or an
   ongoing merge, we need a tool to combine these.  There are a lot of
   corner cases here but in general, if merge X has file F in conflict and
   merge Y has file F resolved, we can take the resolution from Y.

 * Partial merges (in the work-tree copy of a file) that are not yet added
   may be the trickiest.  A simple heuristic would be to look for the
   conflict markers and see if one work-tree copy has a resolution
   where another work-tree copy has a conflict.  Or, though this is
   harder, use the ours/theirs copies in the saved index trees to find
   actual conflicted regions and compare this to the work-tree copy
   to find resolved regions.

 * There is also an obvious question about what to do when combining
   two different proposed resolutions where the stage-zero and/or
   work-tree copies of the files don't match.

None of these preclude the basic ability to save and restore—and of
course transport, through fetch/push—the unmerged state, which I think
is the required enabling technology.  The ideas above are more for
combining parallel merge efforts.  If it's acceptable for dev A to merge
his/her part and pass the result to dev B, who merges theirs, and so
on, the above is not required.

Chris