From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Sat, 17 Feb 2018 11:19:57 +0000 (+0000)
Subject: git-debrebase: NOTES: about divergence and merges
X-Git-Tag: archive/debian/5.0~191
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=commitdiff_plain;h=7f492dae0db33085a692ece232936313be7b44c1;ds=inline

git-debrebase: NOTES: about divergence and merges

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---

diff --git a/NOTES.git-debrebase b/NOTES.git-debrebase
index 2f2b1e8c..2fefa91a 100644
--- a/NOTES.git-debrebase
+++ b/NOTES.git-debrebase
@@ -274,3 +274,43 @@ ideally, would make pseudomerge over dgit view
 would need to check that dgit view is actually dgit view of
   ond of our ancestors
 failing that first push will need --overwrite
+
+========================================
+
+divergence, merges:
+
+same problem
+ if merge, look at branches before merge
+ generate new combined branch
+ pseudomerge to overwrite merge
+
+current avaiable strategies:
+
+ maybe launder foreign branch
+
+ if foreign branch is nmuish, can rebase it onto ours
+
+ could merge breakwaters (use analyse to find them)
+ merge breakwaters (assuming same upstream)
+ manually construct new patch queue by inspection of
+  the other two patch queues
+
+ instead of manually constructing patch queue, could use
+  gbp pq export and git merge the patch queues
+  (ie work with interdiffs)
+
+ if upstreams are different and one is ahead
+  simply treat that as "ours" and
+  do the work to import changes from the other
+
+ if upstreams have diverged, can
+  resolve somehow to make new upstream
+  do new-upstream on each branch separately
+  now reduced to previously "solved" problem
+
+ in future, auto patch queue merge algorithm
+  determine next patch to apply
+  there are three versions o..O, l..L, r..R
+  we have already constructed m (previous patch or merged breakwater)
+  try using vector calculus in the implied cube and compute
+   multiple ways to check consistency ?