git-debrebase: notes re psuedomerges

[dgit.git] / NOTES.git-debrebase

diff --git a/NOTES.git-debrebase b/NOTES.git-debrebase
index 6510c6ec0c294ec554e61e9d1bec8f5dcb2620bd..0310f968dea2a2b0a085b4d40f17236318d54972 100644 (file)
--- a/NOTES.git-debrebase
+++ b/NOTES.git-debrebase
@@ -30,21 +30,35 @@
 =========
 
 special commit tags
+overall format
+  [git-debrebase[ COMMIT-TYPE [ ARGS...]]: PROSE, MORE PROSE]
 
-[git-debrebase split mixed commit: debian part]
-[git-debrebase split mixed commit: upstream part]
-[git-debrebase convert dgit import: debian changes]
-[git-debrebase convert dgit import: upstream changes]
+[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 new-upstream combine . [PIECES...]]
-[git-debrebase new-upstream breakwater NEW-UPSTREAM-VERSION]
-[git-debrebase new-upstream changelog NEW-UPSTREAM-VERSION]
+[git-debrebase upstream-combine . PIECE[ PIECE...]: new upstream]
+[git-debrebase breakwater: new upstream NEW-UPSTREAM-VERSION, merge]
+[git-debrebase: new upstream NEW-UPSTREAM-VERSION, changelog]
 
-[git-debrebase gbp2debrebase drop-patches]
-[git-debrebase declare-upstream breakwater]
+[git-debrebase: gbp2debrebase, drop patches]
+[git-debrebase breakwater: declare upstream]
 
 m{^\[git-debrebase (?:\w*-)?upstream combine \.((?: $extra_orig_namepart_re)+)\]}
 
+Every breakwater 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
+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
+trips up on merges, so that is a useful safety catch.
+
+
 =========
 
 workflow
@@ -160,8 +174,39 @@ so that the overall result will be series of pseudomerges.
 
 ========================================
 
+So, pm handling specifics:
+
+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
+        either 1. one of them or, if there is no maximal one,
+        2. our tip
+
+        ? optionally, according to config always take tip anyway
+
+2. git-debrebase stitch
+
+    makes pseudomerge with will-overwrite
+    deletes will-overwrite
+
+========================================
+
 import from gbp
 
+[ all this is done now:
  inputs:
    current HEAD (patches-unapplied),
      this is going to be the base of the old breakwater
@@ -180,9 +225,13 @@ import from gbp
        commit to remove d/patches
        breakwater pseudomerge with upstream
        "rebase" of pq branch, each commit with d/patches stripped
+]
 
 what about dgit view branch ?
 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
+
+should this be called import or gbp2debrebase as it is now ?
+gbp uses "import" oddly but I'm tempted to use it normally here.