X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;ds=sidebyside;f=README.git-debrebase;h=12e2a65c6bedf4840d3a5b0d896648a2e10a531c;hb=1152570de57130d5b32e8edfa10af1bbc892f2a0;hp=cf0034558137b4c18288310b51b2f559d2d69023;hpb=639956a322235edc152f609e966e2cc56905d40d;p=dgit.git diff --git a/README.git-debrebase b/README.git-debrebase index cf003455..12e2a65c 100644 --- a/README.git-debrebase +++ b/README.git-debrebase @@ -1,93 +1,36 @@ -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 - ---p-----p--A----p--B--C--> plus debian/ (but no debian/patches) - / / / - --#-----#-------#-----> upstream - - 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 - - -p- special 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 `p' 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: * Strip pseudomerges: Rewrite the current branch so it contains no - pseudomerges, turning ...B3 into ...p-A-1-2-B3. (This should - make a note, in your .git/ somewhere, of the latest pseudomerge to - be deleted.) + pseudomerges, turning ...B3 into ...@-A-1-2-B3. (This should + make a note, in your .git/ somewhere, of the original branch + tip so that it can be overwritten with a pseudomerge.) * Cleanup branch: Reorganise the current branch so that the debian/ - changes come first, turning -p-A-1-2-B3 into ...p-A-B-1-2-3. + changes come first, turning -@-A-1-2-B3 into ...@-A-B-1-2-3. * New upstream rebase: Start rebasing onto a new upstream version, - turning ...#...p-A-B-1-2-3 into ...#'.A-B-p'-1-2. This would be a - wrapper around git-rebase, which prepares p' and then tries to - rebase 1 2 onto p'. So if you ask for an interactive rebase p' - doesn't appear in your commit list. + turning ...#..@-A-B-1-2-3 into (...#..@-A-B-|...#'-)@'-1-2. This + would be a wrapper around git-rebase, which prepares @' and then + tries to rebase 1 2 onto @'. So if you ask for an interactive + rebase @' doesn't appear in your commit list. - Note that the rebasing of p into p' cannot fail because p' simply + Note that the construction of @' cannot fail because @' simply copies debian/ from B and and everything else from #'. (Rebasing A and B is undesirable. We want the debian/ files to be non-rebasing so we can `git log' and get the packaging history.) * Record pseudomerge. This is like "committing" your patch queue. - The LH parent is taken from the previous strip pseudomerge. (We - should probably check that this is consistent with what we see in - debian/changelog, but that is not a sufficient check.) + The LH parent is taken from the previously recorded tip. (We could + perhaps check that this is consistent with what we see in + debian/changelog, but that is not a sufficient check so the + recorded tip check is primary.) 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 `p'. -(Indeed I since upstream might copy debian/ from us, I think it is not -easy to reliably distinguish the two parents of a `p'. 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? @@ -101,81 +44,5 @@ would get if you untarred the origs and the debian.tar.gz, and then deleted all the patches without applying them. - -Consider a non-dgit NMU followed by a dgit NMU: - - - - interchange --/--B3!--%--/----E---> - / / - % 4 - / 3 - / 2 - / 1 - 2* &_ - / /| \ - 1 0 00 =XBCD - / - / - --p--A---> breakwater - / - --#--------> upstream - - - Key: - - =XBC% dgit tarball import of .debian.tar.gz containing - Debian packaging including changes B C and patches - - 0 dgit tarball import of upstream tarball - - 00 dgit tarball import of supplementary upstream tarball - - &_ dgit nearly-breakwater import - - &' git-debrebase converted import - - D' git-debrebase converted debian/ changes import - -Want to transform this into: - - I. No new upstream version (0 + 00 eq #) - - --/--B3!--%--/------D--------------/--> - / / / - % 4 4 - / 3 3 - / 2 2 - / 1 1 - 2* &_ / - / /| \ / - 1 0 00 =XBC% / - / / - / / - --p--A-----B-----------------------C--D---> - / - --#-----------------------------------------> - - - II. New upstream (0 + 00 neq #) - - interchange - - --/--B3!--%--/------E--------------/--> - / / / - % 4 4 - / 3 3 - / 2 2 - / 1 1 - 2* &_ / - / /| \ / - 1 0 00 =XBC% / - / / - / / - --p--A-----B--------------------p--C--D---> - / / - --#----------------------- - - / - - -----> - / - &' - /| - 0 00 +dgit import handling +--------------------