# HG changeset patch
# User Martin von Zweigbergk <martinvonz@google.com>
# Date 1578694940 28800
# Node ID 9c9cfecd46000948f442c7585594dedeef5d663a
# Parent  b42ce825308eabb85e874dbff630d6ce7ae537b5
rebase: don't use rebased node as dirstate p2 (BC)

When rebasing a node, we currently use the rebased node as p2 in the
dirstate until just before we commit it (we then change to the desired
parents). This p2 is visible to the user when the rebase gets
interrupted because of merge conflicts. That can be useful to the user
as a reminder of which commit is currently being rebased, but I
believe it's incorrect for a few reasons:

 * I think the dirstate parents should be the ones that will be set
   when the commit is created.

 * I think having two parents means that you're merging those two
   commits, but when rebasing, you're generally grafting, not merging.

 * When rebasing a merge commit, we should use the two desired parents
   as dirstate parents (and we clearly can't have the rebased node as
   a third dirstate parent).

 * `hg graft` (and `hg update --merge`) sets only one parent and `hg
   rebase` should be consistent with that.

I realize that this is a somewhat large user-visible change, but I
think it's worth it because it will simplify things quite a bit.

Differential Revision: https://phab.mercurial-scm.org/D7827

diff -r b42ce825308e -r 9c9cfecd4600 hgext/rebase.py
--- a/hgext/rebase.py	Fri Jan 10 14:17:56 2020 -0800
+++ b/hgext/rebase.py	Fri Jan 10 14:22:20 2020 -0800
@@ -618,6 +618,7 @@
                         repo,
                         rev,
                         p1,
+                        p2,
                         base,
                         self.collapsef,
                         dest,
@@ -642,10 +643,6 @@
                 newnode = self._concludenode(rev, p1, p2, editor)
             else:
                 # Skip commit if we are collapsing
-                if self.inmemory:
-                    self.wctx.setbase(repo[p1])
-                else:
-                    repo.setparents(repo[p1].node())
                 newnode = None
             # Update the state
             if newnode is not None:
@@ -1468,7 +1465,7 @@
         return newnode
 
 
-def rebasenode(repo, rev, p1, base, collapse, dest, wctx):
+def rebasenode(repo, rev, p1, p2, base, collapse, dest, wctx):
     """Rebase a single revision rev on top of p1 using base as merge ancestor"""
     # Merge phase
     # Update to destination and merge it with local
@@ -1502,6 +1499,7 @@
         labels=[b'dest', b'source'],
         wc=wctx,
     )
+    wctx.setparents(p1ctx.node(), repo[p2].node())
     if collapse:
         copies.graftcopies(wctx, ctx, repo[dest])
     else:
diff -r b42ce825308e -r 9c9cfecd4600 relnotes/next
--- a/relnotes/next	Fri Jan 10 14:17:56 2020 -0800
+++ b/relnotes/next	Fri Jan 10 14:22:20 2020 -0800
@@ -21,6 +21,11 @@
 
 == Backwards Compatibility Changes ==
 
+ * When `hg rebase` pauses for merge conflict resolution, the working
+   copy will no longer have the rebased node as a second parent. You
+   can use the new `conflictparents()` revset for finding the other
+   parent during a conflict.
+
 
 == Internal API Changes ==
 
diff -r b42ce825308e -r 9c9cfecd4600 tests/test-rebase-abort.t
--- a/tests/test-rebase-abort.t	Fri Jan 10 14:17:56 2020 -0800
+++ b/tests/test-rebase-abort.t	Fri Jan 10 14:22:20 2020 -0800
@@ -236,7 +236,7 @@
   [1]
 
   $ hg tglog
-  @  4:draft 'C1'
+  %  4:draft 'C1'
   |
   o  3:draft 'B bis'
   |
diff -r b42ce825308e -r 9c9cfecd4600 tests/test-rebase-collapse.t
--- a/tests/test-rebase-collapse.t	Fri Jan 10 14:17:56 2020 -0800
+++ b/tests/test-rebase-collapse.t	Fri Jan 10 14:22:20 2020 -0800
@@ -712,7 +712,7 @@
   |
   | @  2: 82b8abf9c185 'D'
   | |
-  @ |  1: f899f3910ce7 'B'
+  % |  1: f899f3910ce7 'B'
   |/
   o  0: 4a2df7238c3b 'A'
   
@@ -736,7 +736,7 @@
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
   $ hg tglog
-  @  3: 63668d570d21 'C'
+  %  3: 63668d570d21 'C'
   |
   | @  2: 82b8abf9c185 'D'
   | |
diff -r b42ce825308e -r 9c9cfecd4600 tests/test-rebase-conflicts.t
--- a/tests/test-rebase-conflicts.t	Fri Jan 10 14:17:56 2020 -0800
+++ b/tests/test-rebase-conflicts.t	Fri Jan 10 14:22:20 2020 -0800
@@ -456,15 +456,14 @@
   warning: conflicts while merging conflict! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
-The current parents are not 7 and 8 even though that's what we're merging
   $ hg tglog
   @  8:draft 'E'
   |
-  | o  7:draft 'D'
+  | @  7:draft 'D'
   |/
   o  6:draft 'C'
   |
-  | @    5:draft 'F'
+  | %    5:draft 'F'
   | |\
   | | o  4:draft 'E'
   | | |
diff -r b42ce825308e -r 9c9cfecd4600 tests/test-rebase-interruptions.t
--- a/tests/test-rebase-interruptions.t	Fri Jan 10 14:17:56 2020 -0800
+++ b/tests/test-rebase-interruptions.t	Fri Jan 10 14:22:20 2020 -0800
@@ -294,7 +294,7 @@
   $ hg tglogp
   @  7: 401ccec5e39f secret 'C'
   |
-  | @  6: a0b2430ebfb8 secret 'F'
+  | o  6: a0b2430ebfb8 secret 'F'
   | |
   o |  5: 45396c49d53b public 'B'
   | |
@@ -345,7 +345,7 @@
   $ hg tglogp
   @  7: 401ccec5e39f secret 'C'
   |
-  | @  6: a0b2430ebfb8 secret 'F'
+  | o  6: a0b2430ebfb8 secret 'F'
   | |
   o |  5: 45396c49d53b public 'B'
   | |
@@ -395,7 +395,7 @@
   $ hg tglogp
   @  7: 401ccec5e39f secret 'C'
   |
-  | @  6: a0b2430ebfb8 secret 'F'
+  | o  6: a0b2430ebfb8 secret 'F'
   | |
   o |  5: 45396c49d53b public 'B'
   | |
diff -r b42ce825308e -r 9c9cfecd4600 tests/test-rebase-obsolete.t
--- a/tests/test-rebase-obsolete.t	Fri Jan 10 14:17:56 2020 -0800
+++ b/tests/test-rebase-obsolete.t	Fri Jan 10 14:22:20 2020 -0800
@@ -1795,19 +1795,15 @@
   $ hg log -G
   @  2:b18e25de2cf5 D
   |
-  | @  1:2ec65233581b B (pruned using prune)
-  |/
   o  0:426bada5c675 A
   
   $ hg summary
   parent: 2:b18e25de2cf5 tip
    D
-  parent: 1:2ec65233581b  (obsolete)
-   B
   branch: default
-  commit: 2 modified, 1 unknown, 1 unresolved (merge)
+  commit: 1 modified, 1 added, 1 unknown, 1 unresolved
   update: (current)
-  phases: 3 draft
+  phases: 2 draft
   rebase: 0 rebased, 2 remaining (rebase --continue)
 
   $ hg rebase --abort
diff -r b42ce825308e -r 9c9cfecd4600 tests/test-rebase-parameters.t
--- a/tests/test-rebase-parameters.t	Fri Jan 10 14:17:56 2020 -0800
+++ b/tests/test-rebase-parameters.t	Fri Jan 10 14:22:20 2020 -0800
@@ -481,11 +481,9 @@
   $ hg summary
   parent: 1:56daeba07f4b 
    c2
-  parent: 2:e4e3f3546619 tip
-   c2b
   branch: default
-  commit: 1 modified, 1 unresolved (merge)
-  update: (current)
+  commit: 1 unresolved (clean)
+  update: 1 new changesets, 2 branch heads (merge)
   phases: 3 draft
   rebase: 0 rebased, 1 remaining (rebase --continue)
 
diff -r b42ce825308e -r 9c9cfecd4600 tests/test-rebase-transaction.t
--- a/tests/test-rebase-transaction.t	Fri Jan 10 14:17:56 2020 -0800
+++ b/tests/test-rebase-transaction.t	Fri Jan 10 14:22:20 2020 -0800
@@ -114,7 +114,7 @@
   |
   | @  4: Z
   | |
-  @ |  3: C
+  % |  3: C
   | |
   | o  2: Y
   | |
@@ -123,9 +123,9 @@
   o  0: A
   
   $ hg st
-  M C
   M conflict
   A B
+  A C
   ? conflict.orig
   $ echo resolved > conflict
   $ hg resolve -m