tests: demonstrate how continuing rebase after upgrade can result in merge

If the user starts a rebase with an hg version before 9c9cfecd4600
(rebase: don't use rebased node as dirstate p2 (BC), 2020-01-10) and
then runs into conflicts, they will be dropped out to the shell with
the rebased node set as the dirstate's second parent. If they then
upgrade to a later hg version, it will respect the dirstate's parents
and will create a merge commit even if the user was rebasing a
non-merge commit.

Differential Revision: https://phab.mercurial-scm.org/D8355

tests/test-rebase-interruptions.t

@@ -1,480 +1,545 b''
   $ cat >> $HGRCPATH <<EOF
   > [extensions]
   > rebase=
   > 
   > [phases]
   > publish=False
   > 
   > [alias]
   > tglog = log -G --template "{rev}: {node|short} '{desc}' {branches}\n"
   > tglogp = log -G --template "{rev}: {node|short} {phase} '{desc}' {branches}\n"
   > EOF
 
 
   $ hg init a
   $ cd a
 
   $ echo A > A
   $ hg ci -Am A
   adding A
 
   $ echo B > B
   $ hg ci -Am B
   adding B
 
   $ echo C >> A
   $ hg ci -m C
 
   $ hg up -q -C 0
 
   $ echo D >> A
   $ hg ci -m D
   created new head
 
   $ echo E > E
   $ hg ci -Am E
   adding E
 
   $ cd ..
 
 
 Changes during an interruption - continue:
 
   $ hg clone -q -u . a a1
   $ cd a1
 
   $ hg tglog
   @  4: ae36e8e3dfd7 'E'
   |
   o  3: 46b37eabc604 'D'
   |
   | o  2: 965c486023db 'C'
   | |
   | o  1: 27547f69f254 'B'
   |/
   o  0: 4a2df7238c3b 'A'
   
 Rebasing B onto E:
 
   $ hg rebase -s 1 -d 4
   rebasing 1:27547f69f254 "B"
   rebasing 2:965c486023db "C"
   merging A
   warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
 
 Force a commit on C during the interruption:
 
   $ hg up -q -C 2 --config 'extensions.rebase=!'
 
   $ echo 'Extra' > Extra
   $ hg add Extra
   $ hg ci -m 'Extra' --config 'extensions.rebase=!'
 
 Force this commit onto secret phase
 
   $ hg phase --force --secret 6
 
   $ hg tglogp
   @  6: deb5d2f93d8b secret 'Extra'
   |
   | o  5: 45396c49d53b draft 'B'
   | |
   | o  4: ae36e8e3dfd7 draft 'E'
   | |
   | o  3: 46b37eabc604 draft 'D'
   | |
   o |  2: 965c486023db draft 'C'
   | |
   o |  1: 27547f69f254 draft 'B'
   |/
   o  0: 4a2df7238c3b draft 'A'
   
 Resume the rebasing:
 
   $ hg rebase --continue
   already rebased 1:27547f69f254 "B" as 45396c49d53b
   rebasing 2:965c486023db "C"
   merging A
   warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
 
 Solve the conflict and go on:
 
   $ echo 'conflict solved' > A
   $ rm A.orig
   $ hg resolve -m A
   (no more unresolved files)
   continue: hg rebase --continue
 
   $ hg rebase --continue
   already rebased 1:27547f69f254 "B" as 45396c49d53b
   rebasing 2:965c486023db "C"
   warning: orphaned descendants detected, not stripping 27547f69f254, 965c486023db
 
   $ hg tglogp
   o  7: d2d25e26288e draft 'C'
   |
   | o  6: deb5d2f93d8b secret 'Extra'
   | |
   o |  5: 45396c49d53b draft 'B'
   | |
   @ |  4: ae36e8e3dfd7 draft 'E'
   | |
   o |  3: 46b37eabc604 draft 'D'
   | |
   | o  2: 965c486023db draft 'C'
   | |
   | o  1: 27547f69f254 draft 'B'
   |/
   o  0: 4a2df7238c3b draft 'A'
   
   $ cd ..
 
 
 Changes during an interruption - abort:
 
   $ hg clone -q -u . a a2
   $ cd a2
 
   $ hg tglog
   @  4: ae36e8e3dfd7 'E'
   |
   o  3: 46b37eabc604 'D'
   |
   | o  2: 965c486023db 'C'
   | |
   | o  1: 27547f69f254 'B'
   |/
   o  0: 4a2df7238c3b 'A'
   
 Rebasing B onto E:
 
   $ hg rebase -s 1 -d 4
   rebasing 1:27547f69f254 "B"
   rebasing 2:965c486023db "C"
   merging A
   warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
 
 Force a commit on B' during the interruption:
 
   $ hg up -q -C 5 --config 'extensions.rebase=!'
 
   $ echo 'Extra' > Extra
   $ hg add Extra
   $ hg ci -m 'Extra' --config 'extensions.rebase=!'
 
   $ hg tglog
   @  6: 402ee3642b59 'Extra'
   |
   o  5: 45396c49d53b 'B'
   |
   o  4: ae36e8e3dfd7 'E'
   |
   o  3: 46b37eabc604 'D'
   |
   | o  2: 965c486023db 'C'
   | |
   | o  1: 27547f69f254 'B'
   |/
   o  0: 4a2df7238c3b 'A'
   
 Abort the rebasing:
 
   $ hg rebase --abort
   warning: new changesets detected on destination branch, can't strip
   rebase aborted
 
   $ hg tglog
   @  6: 402ee3642b59 'Extra'
   |
   o  5: 45396c49d53b 'B'
   |
   o  4: ae36e8e3dfd7 'E'
   |
   o  3: 46b37eabc604 'D'
   |
   | o  2: 965c486023db 'C'
   | |
   | o  1: 27547f69f254 'B'
   |/
   o  0: 4a2df7238c3b 'A'
   
   $ cd ..
 
 Changes during an interruption - abort (again):
 
   $ hg clone -q -u . a a3
   $ cd a3
 
   $ hg tglogp
   @  4: ae36e8e3dfd7 draft 'E'
   |
   o  3: 46b37eabc604 draft 'D'
   |
   | o  2: 965c486023db draft 'C'
   | |
   | o  1: 27547f69f254 draft 'B'
   |/
   o  0: 4a2df7238c3b draft 'A'
   
 Rebasing B onto E:
 
   $ hg rebase -s 1 -d 4
   rebasing 1:27547f69f254 "B"
   rebasing 2:965c486023db "C"
   merging A
   warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
 
 Change phase on B and B'
 
   $ hg up -q -C 5 --config 'extensions.rebase=!'
   $ hg phase --public 1
   $ hg phase --public 5
   $ hg phase --secret -f 2
 
   $ hg tglogp
   @  5: 45396c49d53b public 'B'
   |
   o  4: ae36e8e3dfd7 public 'E'
   |
   o  3: 46b37eabc604 public 'D'
   |
   | o  2: 965c486023db secret 'C'
   | |
   | o  1: 27547f69f254 public 'B'
   |/
   o  0: 4a2df7238c3b public 'A'
   
 Abort the rebasing:
 
   $ hg rebase --abort
   warning: can't clean up public changesets 45396c49d53b
   rebase aborted
 
   $ hg tglogp
   @  5: 45396c49d53b public 'B'
   |
   o  4: ae36e8e3dfd7 public 'E'
   |
   o  3: 46b37eabc604 public 'D'
   |
   | o  2: 965c486023db secret 'C'
   | |
   | o  1: 27547f69f254 public 'B'
   |/
   o  0: 4a2df7238c3b public 'A'
   
 Test rebase interrupted by hooks
 
   $ hg up 2
   1 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ echo F > F
   $ hg add F
   $ hg ci -m F
 
   $ cd ..
 
+Continue rebase after upgrading from an hg version before 9c9cfecd4600:
+
+  $ hg clone -q -u . a a4
+  $ cd a4
+
+  $ hg tglog
+  @  4: ae36e8e3dfd7 'E'
+  |
+  o  3: 46b37eabc604 'D'
+  |
+  | o  2: 965c486023db 'C'
+  | |
+  | o  1: 27547f69f254 'B'
+  |/
+  o  0: 4a2df7238c3b 'A'
+  
+  $ hg rebase -s 1 -d 4
+  rebasing 1:27547f69f254 "B"
+  rebasing 2:965c486023db "C"
+  merging A
+  warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
+  unresolved conflicts (see hg resolve, then hg rebase --continue)
+  [1]
+  $ hg tglog
+  @  5: 45396c49d53b 'B'
+  |
+  o  4: ae36e8e3dfd7 'E'
+  |
+  o  3: 46b37eabc604 'D'
+  |
+  | %  2: 965c486023db 'C'
+  | |
+  | o  1: 27547f69f254 'B'
+  |/
+  o  0: 4a2df7238c3b 'A'
+  
+Simulate having run the above with an older hg version by manually setting
+two dirstate parents. We should not get a merge commit when we continue.
+  $ hg debugsetparents 5 2
+  $ echo 'conflict solved' > A
+  $ hg resolve -m A
+  (no more unresolved files)
+  continue: hg rebase --continue
+  $ hg rebase --continue
+  already rebased 1:27547f69f254 "B" as 45396c49d53b
+  rebasing 2:965c486023db "C"
+  warning: orphaned descendants detected, not stripping 27547f69f254, 965c486023db
+BROKEN: we should not have a merge commit here
+  $ hg tglog
+  o    6: 567335b578a0 'C'
+  |\
+  | o  5: 45396c49d53b 'B'
+  | |
+  | @  4: ae36e8e3dfd7 'E'
+  | |
+  | o  3: 46b37eabc604 'D'
+  | |
+  o |  2: 965c486023db 'C'
+  | |
+  o |  1: 27547f69f254 'B'
+  |/
+  o  0: 4a2df7238c3b 'A'
+  
+  $ cd ..
+
 (precommit version)
 
   $ cp -R a3 hook-precommit
   $ cd hook-precommit
   $ hg rebase --source 2 --dest 5 --tool internal:other --config 'hooks.precommit=hg status | grep "M A"'
   rebasing 2:965c486023db "C"
   M A
   rebasing 6:a0b2430ebfb8 "F" (tip)
   abort: precommit hook exited with status 1
   [255]
   $ hg tglogp
   @  7: 401ccec5e39f secret 'C'
   |
   | o  6: a0b2430ebfb8 secret 'F'
   | |
   o |  5: 45396c49d53b public 'B'
   | |
   o |  4: ae36e8e3dfd7 public 'E'
   | |
   o |  3: 46b37eabc604 public 'D'
   | |
   | o  2: 965c486023db secret 'C'
   | |
   | o  1: 27547f69f254 public 'B'
   |/
   o  0: 4a2df7238c3b public 'A'
   
   $ hg rebase --continue
   already rebased 2:965c486023db "C" as 401ccec5e39f
   rebasing 6:a0b2430ebfb8 "F"
   saved backup bundle to $TESTTMP/hook-precommit/.hg/strip-backup/965c486023db-aa6250e7-rebase.hg
   $ hg tglogp
   @  6: 6e92a149ac6b secret 'F'
   |
   o  5: 401ccec5e39f secret 'C'
   |
   o  4: 45396c49d53b public 'B'
   |
   o  3: ae36e8e3dfd7 public 'E'
   |
   o  2: 46b37eabc604 public 'D'
   |
   | o  1: 27547f69f254 public 'B'
   |/
   o  0: 4a2df7238c3b public 'A'
   
   $ cd ..
 
 (pretxncommit version)
 
   $ cp -R a3 hook-pretxncommit
   $ cd hook-pretxncommit
   $ hg rebase --source 2 --dest 5 --tool internal:other \
   >     --config 'hooks.tonative.pretxncommit=True' --config 'hooks.pretxncommit=hg log -r $HG_NODE | grep "summary:     C"'
   rebasing 2:965c486023db "C"
   summary:     C
   rebasing 6:a0b2430ebfb8 "F" (tip)
   transaction abort!
   rollback completed
   abort: pretxncommit hook exited with status 1
   [255]
   $ hg tglogp
   @  7: 401ccec5e39f secret 'C'
   |
   | o  6: a0b2430ebfb8 secret 'F'
   | |
   o |  5: 45396c49d53b public 'B'
   | |
   o |  4: ae36e8e3dfd7 public 'E'
   | |
   o |  3: 46b37eabc604 public 'D'
   | |
   | o  2: 965c486023db secret 'C'
   | |
   | o  1: 27547f69f254 public 'B'
   |/
   o  0: 4a2df7238c3b public 'A'
   
   $ hg rebase --continue
   already rebased 2:965c486023db "C" as 401ccec5e39f
   rebasing 6:a0b2430ebfb8 "F"
   saved backup bundle to $TESTTMP/hook-pretxncommit/.hg/strip-backup/965c486023db-aa6250e7-rebase.hg
   $ hg tglogp
   @  6: 6e92a149ac6b secret 'F'
   |
   o  5: 401ccec5e39f secret 'C'
   |
   o  4: 45396c49d53b public 'B'
   |
   o  3: ae36e8e3dfd7 public 'E'
   |
   o  2: 46b37eabc604 public 'D'
   |
   | o  1: 27547f69f254 public 'B'
   |/
   o  0: 4a2df7238c3b public 'A'
   
   $ cd ..
 
 (pretxnclose version)
 
   $ cp -R a3 hook-pretxnclose
   $ cd hook-pretxnclose
   $ hg rebase --source 2 --dest 5 --tool internal:other --config 'hooks.pretxnclose=hg log -r tip | grep "summary:     C"'
   rebasing 2:965c486023db "C"
   summary:     C
   rebasing 6:a0b2430ebfb8 "F" (tip)
   transaction abort!
   rollback completed
   abort: pretxnclose hook exited with status 1
   [255]
   $ hg tglogp
   @  7: 401ccec5e39f secret 'C'
   |
   | o  6: a0b2430ebfb8 secret 'F'
   | |
   o |  5: 45396c49d53b public 'B'
   | |
   o |  4: ae36e8e3dfd7 public 'E'
   | |
   o |  3: 46b37eabc604 public 'D'
   | |
   | o  2: 965c486023db secret 'C'
   | |
   | o  1: 27547f69f254 public 'B'
   |/
   o  0: 4a2df7238c3b public 'A'
   
   $ hg rebase --continue
   already rebased 2:965c486023db "C" as 401ccec5e39f
   rebasing 6:a0b2430ebfb8 "F"
   saved backup bundle to $TESTTMP/hook-pretxnclose/.hg/strip-backup/965c486023db-aa6250e7-rebase.hg
   $ hg tglogp
   @  6: 6e92a149ac6b secret 'F'
   |
   o  5: 401ccec5e39f secret 'C'
   |
   o  4: 45396c49d53b public 'B'
   |
   o  3: ae36e8e3dfd7 public 'E'
   |
   o  2: 46b37eabc604 public 'D'
   |
   | o  1: 27547f69f254 public 'B'
   |/
   o  0: 4a2df7238c3b public 'A'
   
   $ cd ..
 
 Make sure merge state is cleaned up after a no-op rebase merge (issue5494)
   $ hg init repo
   $ cd repo
   $ echo a > a
   $ hg commit -qAm base
   $ echo b >> a
   $ hg commit -qm b
   $ hg up '.^'
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ echo c >> a
   $ hg commit -qm c
   $ hg rebase -s 1 -d 2 --noninteractive
   rebasing 1:fdaca8533b86 "b"
   merging a
   warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
   $ echo a > a
   $ echo c >> a
   $ hg resolve --mark a
   (no more unresolved files)
   continue: hg rebase --continue
   $ hg rebase --continue
   rebasing 1:fdaca8533b86 "b"
   note: not rebasing 1:fdaca8533b86 "b", its destination already has all its changes
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/fdaca8533b86-7fd70513-rebase.hg
   $ hg resolve --list
   $ test -d .hg/merge
   [1]
 Now try again with --collapse
   $ hg unbundle -q .hg/strip-backup/fdaca8533b86-7fd70513-rebase.hg
   $ hg rebase -s 2 -d 1 --noninteractive --collapse
   rebasing 2:fdaca8533b86 "b" (tip)
   merging a
   warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
   $ echo a > a
   $ echo c >> a
   $ hg resolve --mark a
   (no more unresolved files)
   continue: hg rebase --continue
   $ hg rebase --continue
   rebasing 2:fdaca8533b86 "b" (tip)
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/fdaca8533b86-7fd70513-rebase.hg
   $ hg resolve --list
   $ test -d .hg/merge
   [1]