-My preferred answer is that it is a constantly rebasing branch topped
-with a series of pseudomerges to make it fast-forwarding.
-
- ------/--A!----/--B3!--%--/--> interchange view
- / / / with debian/ directory
- % % % all upstream changes applied
- / / / 3.0 (quilt) has debian/patches
- / / 3*
- / / /
- 2* 2* 2
- / / /
- 1 1 1 `breakwater' branch, merging baseline
- / / / unmodified upstream code
- ---@-----@--A----@--B--C plus debian/ (but no debian/patches)
- / / / no ref refers to this: we
- --#-----#-------#-----> upstream reconstruct its identity by
- inspecting interchange branch
- Key:
-
- 1,2,3 commits touching upstream files only
- A,B,C commits touching debian/ only
- B3 mixed commit (eg made by an NMUer)
- # upstream releases
-
- -@- anchor merge, takes contents of debian/ from the
- / previous `breakwater' commit and rest from upstream
-
- -/- pseudomerge; contents are identical to
- / parent lower on diagram.
-
- % dgit-generated commit of debian/patches.
- `3.0 (quilt)' only; dropped by rebase tool.
-
- * Maintainer's HEAD was here while they were editing,
- before they said they were done, at which point their
- tools generated [% and] -/- commit[s] to convert to
- the fast-forwarding interchange branch. (Maybe the
- tooling is simply `dgit push'.)
-
- ! NMUer's HEAD was here when they said `dgit push'.
- Rebase branch launderer turns each ! into an
- equivalent *.
-
-
-Looking from the tip of the interchange view, it is I think always
-possible to classify these commits appropriately: pseudomerges are
-fairly obvious (if all three trees are identical, we descend to the
-parent with the most recent commit date), and the `@' special merge is
-the only non-pseudo merge and has a special form.
-
So it would be possible to write a `git-debrebase' tool which would
take (for example) B4, above, and be able to perform functions like:
Maybe some of these operations should automatically edit
debian/changelog.
-The only thing that this can't easily do is permit nonlinear (ie,
-merging) history on the `packaging-only' branch, because upstream
-might contain debian/ files too, so it is not possible to distinguish
-a merge of two `packaging-only' branches from the special merge `@'.
-(Indeed I since upstream might copy debian/ from us, I think it is not
-easy to reliably distinguish the two parents of a `@'. In the most
-exciting edge case, upstream might `git merge' a previous instance of
-our interchange view, but I think even then everything still works.)
Sean Whitton writes ("Re: Feedback on 3.0 source format problems"):
> Does the [breakwater] branch contain debian/ alone?
~ianmdlvl / dgit.git / blobdiff