X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=blobdiff_plain;f=NOTES.git-debrebase;h=ca78c9386414aeff95a719b7ca2d37642051194b;hp=4d7cf20f26912c40babad44d646d5832b31612f5;hb=9157ed980b82c0664685e1cf8941c360fb2b11e1;hpb=e6c5fe85824337be49d77f89aa388c82361784e4 diff --git a/NOTES.git-debrebase b/NOTES.git-debrebase index 4d7cf20f..ca78c938 100644 --- a/NOTES.git-debrebase +++ b/NOTES.git-debrebase @@ -1,5 +1,19 @@ +TODO + --anchor option to specify commit(s) to treat as as anchor(s) + + rename "launder" operation to "launder-v0" + + reference docs + git-debrebase(5) data model + git-debrebase(1) command line + tutorial + dgit-maint-debrebase(7) + someone should set branch..mergeOptions to include --ff-only ? + + clean up remains of NOTES and README + + arrange for dgit to automatically stitch on push -# # git-ffqrebase start [BASE] # # records previous HEAD so it can be overwritten # # records base for future git-ffqrebase @@ -8,9 +22,7 @@ # git-ffqrebase finish # git-ffqrebase status [BRANCH] # -# refs/ffqrebase-prev/BRANCH BRANCH may be refs/...; if not it means -# refs/ffqrebase-base/BRANCH refs/heads/BRANCH -# zero, one, or both of these may exist +# refs/ffq-prev/REF relates to refs/REF # # git-debrebase without start, if already started, is willing # to strip pseudomerges provided that they overwrite exactly @@ -36,26 +48,29 @@ overall format [git-debrebase: split mixed commit, debian part] [git-debrebase: split mixed commit, upstream-part] [git-debrebase: convert dgit import, debian changes] -[git-debrebase breakwater: convert dgit import, upstream changes] +[git-debrebase anchor: convert dgit import, upstream changes] [git-debrebase upstream-combine . PIECE[ PIECE...]: new upstream] -[git-debrebase breakwater: new upstream NEW-UPSTREAM-VERSION, merge] +[git-debrebase anchor: new upstream NEW-UPSTREAM-VERSION, merge] [git-debrebase: new upstream NEW-UPSTREAM-VERSION, changelog] -[git-debrebase: gbp2debrebase, drop patches] -[git-debrebase breakwater: declare upstream] +[git-debrebase convert-from-gbp: drop patches] +[git-debrebase anchor: declare upstream] +[git-debrebase pseudomerge: stitch] + +[git-debrebase convert-to-gbp: commit patches] m{^\[git-debrebase (?:\w*-)?upstream combine \.((?: $extra_orig_namepart_re)+)\]} -Every breakwater commit must be a merge. In principle, this is not +Every anchor commit must be a merge. In principle, this is not necessary. After all, we are relying on the - [git-debrebase breakwater: ...] -commit message annotation in "declare" breakwater merges (which -do not have any upstream changes), to distinguish those breakwater + [git-debrebase anchor: ...] +commit message annotation in "declare" anchor merges (which +do not have any upstream changes), to distinguish those anchor merges from ordinary pseudomerges (which we might just try to strip). However, the user is going to be doing git-rebase a lot. We really -don't want them to rewrite a breakwater base commit. git-rebase +don't want them to rewrite an anchor commit. git-rebase trips up on merges, so that is a useful safety catch. @@ -174,6 +189,69 @@ so that the overall result will be series of pseudomerges. ======================================== +So, pm handling specifics: + +strategy is to avoid making needless pseudomerges +pseudomerges that exist will be preserved +(by being included in will-overwrite) + +This is good because the presence of a pseudomerge means we know we +want to keep it; and that allows explicit control over history detail +level. + +It does mean we must avoid making the pseudomerges unnecessarily. +They should be made just before (ideally, part of) dgit push. + +1. git-debrebase [-i etc.] + + should: + check for will-overwrite + if is already a will-overwrite, fine, do no more + if not: + + check our origin branch exists and we are ff from it + if not fail + + check our other might-be-pushed to branches + check we are ff from them + if not fail + + set will-overwrite to something which is ff from + all above branches + + we use our tip, as discussed above + (optionally, can use some other commit which is ff + from all of the above, eg one of them) + +N. git-debrebase [--noop-ok] record-ffq-prev + + does what is described above + +2. git-debrebase [--noop-ok] stitch + + makes pseudomerge with will-overwrite + deletes will-overwrite + + we will teach dgit to do + git-debrebase stitch + +3. git-debrebase push + + like git push only does stitch first + ??? command line parsing! + +4. git-debrebase release + + stiches, finalises changelog, signs tags, pushes everything + for the future, when there is some automatic builder + +will-overwrite for each ref + refs/heads/FOO +is + refs/ffq-prev/FOO + +======================================== + import from gbp [ all this is done now: @@ -193,7 +271,7 @@ import from gbp new breakwater is old HEAD commit to remove d/patches - breakwater pseudomerge with upstream + anchor merge with upstream "rebase" of pq branch, each commit with d/patches stripped ] @@ -202,3 +280,43 @@ 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 ?