tests/test-graft-interrupted.t

windows: degrade to py2 behavior when reading a non-symlink as a symlink

While waiting for the push to hg-committed in WSL to complete, I ran a
`phabimport` from Windows and got this traceback:

    $ hg phabimport 11313
    ** Unknown exception encountered with possibly-broken third-party extension "mercurial_keyring" (version N/A)
    ** which supports versions unknown of Mercurial.
    ** Please disable "mercurial_keyring" and try your action again.
    ** If that fixes the bug please report it to https://foss.heptapod.net/mercurial/mercurial_keyring/issues
    ** Python 3.9.5 (default, May  6 2021, 17:29:31) [MSC v.1928 64 bit (AMD64)]
    ** Mercurial Distributed SCM (version 5.9rc1+hg32.0e2f5733563d)
    ** Extensions loaded: absorb, blackbox, evolve 10.3.3, extdiff, fastannotate, fix, mercurial_keyring, mq, phabblocker 20210126, phabricator, rebase, show, strip, topic 0.22.3
    Traceback (most recent call last):
      File "mercurial.lock", line 279, in _trylock
      File "mercurial.vfs", line 202, in makelock
      File "mercurial.util", line 2147, in makelock
    FileExistsError: [WinError 183] Cannot create a file when that file already exists: b'hp-omen:78348' -> b'C:\\Users\\Matt\\hg/.hg/store/lock'

    During handling of the above exception, another exception occurred:

    Traceback (most recent call last):
      File "<string>", line 24, in <module>
      File "mercurial.dispatch", line 144, in run
      File "mercurial.dispatch", line 250, in dispatch
      File "mercurial.dispatch", line 294, in _rundispatch
      File "mercurial.dispatch", line 470, in _runcatch
      File "mercurial.dispatch", line 480, in _callcatch
      File "mercurial.scmutil", line 153, in callcatch
      File "mercurial.dispatch", line 460, in _runcatchfunc
      File "mercurial.dispatch", line 1273, in _dispatch
      File "mercurial.dispatch", line 918, in runcommand
      File "mercurial.dispatch", line 1285, in _runcommand
      File "mercurial.dispatch", line 1271, in <lambda>
      File "mercurial.util", line 1886, in check
      File "mercurial.util", line 1886, in check
      File "hgext.mq", line 4239, in mqcommand
      File "mercurial.util", line 1886, in check
      File "mercurial.util", line 1886, in check
      File "hgext.phabricator", line 314, in inner
      File "hgext.phabricator", line 2222, in phabimport
      File "hgext.phabricator", line 2123, in readpatch
      File "hgext.phabricator", line 2199, in _write
      File "mercurial.localrepo", line 2956, in lock
      File "mercurial.localrepo", line 2918, in _lock
      File "mercurial.lock", line 152, in trylock
      File "mercurial.lock", line 283, in _trylock
      File "mercurial.lock", line 314, in _readlock
      File "mercurial.vfs", line 221, in readlock
      File "mercurial.util", line 2163, in readlock
      File "mercurial.windows", line 619, in readlink
    ValueError: not a symbolic link

Both exceptions look accurate (the file exists, and the Windows side can't read
WSL side symlinks).  I didn't try to reproduce this entirely within the Windows
side, but we can do better than a cryptic stacktrace.  With this change, the
same scenario results in this abort:

    abort: C:\Users\Matt\hg/.hg/store/lock: The file cannot be accessed by the system

When both the `push` and `phabimport` are done on the Windows side, it prints a
message about waiting for the lock, and successfully applies the patch after the
push completes.

I'm not sure if there's enough info to be able to convert the abort into the
wait scenario.  As it stands now, we don't support symlinks on Windows, which
requires either a UAC Administrator level process or an opt-in in developer
mode, and there are several places where the new symlink on Windows support in
py3 was explicitly disabled in order to get tests to pass quicker.

Differential Revision: https://phab.mercurial-scm.org/D11333

#testcases abortcommand abortflag

#if abortflag
  $ cat >> $HGRCPATH <<EOF
  > [alias]
  > abort = graft --abort
  > EOF
#endif


Testing the reading of old format graftstate file with newer mercurial

  $ hg init oldgraft
  $ cd oldgraft
  $ for ch in a b c; do echo foo > $ch; hg add $ch; hg ci -Aqm "added "$ch; done;
  $ hg log -GT "{rev}:{node|short} {desc}\n"
  @  2:8be98ac1a569 added c
  |
  o  1:80e6d2c47cfe added b
  |
  o  0:f7ad41964313 added a
  
  $ hg up 0
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo bar > b
  $ hg add b
  $ hg ci -m "bar to b"
  created new head
  $ hg graft -r 1 -r 2
  grafting 1:80e6d2c47cfe "added b"
  merging b
  warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

Writing the nodes in old format to graftstate

  $ hg log -r 1 -r 2 -T '{node}\n' > .hg/graftstate
  $ echo foo > b
  $ hg resolve -m
  (no more unresolved files)
  continue: hg graft --continue
  $ hg graft --continue
  grafting 1:80e6d2c47cfe "added b"
  grafting 2:8be98ac1a569 "added c"

Testing that --user is preserved during conflicts and value is reused while
running `hg graft --continue`

  $ hg log -G
  @  changeset:   5:711e9fa999f1
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     added c
  |
  o  changeset:   4:e5ad7353b408
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     added b
  |
  o  changeset:   3:9e887f7a939c
  |  parent:      0:f7ad41964313
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     bar to b
  |
  | o  changeset:   2:8be98ac1a569
  | |  user:        test
  | |  date:        Thu Jan 01 00:00:00 1970 +0000
  | |  summary:     added c
  | |
  | o  changeset:   1:80e6d2c47cfe
  |/   user:        test
  |    date:        Thu Jan 01 00:00:00 1970 +0000
  |    summary:     added b
  |
  o  changeset:   0:f7ad41964313
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     added a
  

  $ hg up '.^^'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ hg graft -r 1 -r 2 --user batman
  grafting 1:80e6d2c47cfe "added b"
  merging b
  warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ echo wat > b
  $ hg resolve -m
  (no more unresolved files)
  continue: hg graft --continue

  $ hg graft --continue
  grafting 1:80e6d2c47cfe "added b"
  grafting 2:8be98ac1a569 "added c"

  $ hg log -Gr 3::
  @  changeset:   7:11a36ffaacf2
  |  tag:         tip
  |  user:        batman
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     added c
  |
  o  changeset:   6:76803afc6511
  |  parent:      3:9e887f7a939c
  |  user:        batman
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     added b
  |
  | o  changeset:   5:711e9fa999f1
  | |  user:        test
  | |  date:        Thu Jan 01 00:00:00 1970 +0000
  | |  summary:     added c
  | |
  | o  changeset:   4:e5ad7353b408
  |/   user:        test
  |    date:        Thu Jan 01 00:00:00 1970 +0000
  |    summary:     added b
  |
  o  changeset:   3:9e887f7a939c
  |  parent:      0:f7ad41964313
  ~  user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     bar to b
  
Test that --date is preserved and reused in `hg graft --continue`

  $ hg up '.^^'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg graft -r 1 -r 2 --date '1234560000 120'
  grafting 1:80e6d2c47cfe "added b"
  merging b
  warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ echo foobar > b
  $ hg resolve -m
  (no more unresolved files)
  continue: hg graft --continue
  $ hg graft --continue
  grafting 1:80e6d2c47cfe "added b"
  grafting 2:8be98ac1a569 "added c"

  $ hg log -Gr '.^^::.'
  @  changeset:   9:1896b76e007a
  |  tag:         tip
  |  user:        test
  |  date:        Fri Feb 13 21:18:00 2009 -0002
  |  summary:     added c
  |
  o  changeset:   8:ce2b4f1632af
  |  parent:      3:9e887f7a939c
  |  user:        test
  |  date:        Fri Feb 13 21:18:00 2009 -0002
  |  summary:     added b
  |
  o  changeset:   3:9e887f7a939c
  |  parent:      0:f7ad41964313
  ~  user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     bar to b
  
Test that --log is preserved and reused in `hg graft --continue`

  $ hg up '.^^'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg graft -r 1 -r 2 --log
  grafting 1:80e6d2c47cfe "added b"
  merging b
  warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ echo foobar > b
  $ hg resolve -m
  (no more unresolved files)
  continue: hg graft --continue

  $ hg graft --continue
  grafting 1:80e6d2c47cfe "added b"
  grafting 2:8be98ac1a569 "added c"

  $ hg log -GT "{rev}:{node|short} {desc}" -r '.^^::.'
  @  11:30c1050a58b2 added c
  |  (grafted from 8be98ac1a56990c2d9ca6861041b8390af7bd6f3)
  o  10:ec7eda2313e2 added b
  |  (grafted from 80e6d2c47cfe5b3185519568327a17a061c7efb6)
  o  3:9e887f7a939c bar to b
  |
  ~

  $ cd ..

Testing the --stop flag of `hg graft` which stops the interrupted graft

  $ hg init stopgraft
  $ cd stopgraft
  $ for ch in a b c d; do echo $ch > $ch; hg add $ch; hg ci -Aqm "added "$ch; done;

  $ hg log -G
  @  changeset:   3:9150fe93bec6
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     added d
  |
  o  changeset:   2:155349b645be
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     added c
  |
  o  changeset:   1:5f6d8a4bf34a
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     added b
  |
  o  changeset:   0:9092f1db7931
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     added a
  
  $ hg up '.^^'
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved

  $ echo foo > d
  $ hg ci -Aqm "added foo to d"

  $ hg graft --stop
  abort: no interrupted graft found
  [20]

  $ hg graft -r 3
  grafting 3:9150fe93bec6 "added d"
  merging d
  warning: conflicts while merging d! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ hg graft --stop --continue
  abort: cannot specify both --stop and --continue
  [10]

  $ hg graft --stop -U
  abort: cannot specify both --stop and --user
  [10]
  $ hg graft --stop --rev 4
  abort: cannot specify both --stop and --rev
  [10]
  $ hg graft --stop --log
  abort: cannot specify both --stop and --log
  [10]

  $ hg graft --stop
  stopped the interrupted graft
  working directory is now at a0deacecd59d

  $ hg diff

  $ hg log -Gr '.'
  @  changeset:   4:a0deacecd59d
  |  tag:         tip
  ~  parent:      1:5f6d8a4bf34a
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     added foo to d
  
  $ hg graft -r 2 -r 3
  grafting 2:155349b645be "added c"
  grafting 3:9150fe93bec6 "added d"
  merging d
  warning: conflicts while merging d! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ hg graft --stop
  stopped the interrupted graft
  working directory is now at 75b447541a9e

  $ hg diff

  $ hg log -G -T "{rev}:{node|short} {desc}"
  @  5:75b447541a9e added c
  |
  o  4:a0deacecd59d added foo to d
  |
  | o  3:9150fe93bec6 added d
  | |
  | o  2:155349b645be added c
  |/
  o  1:5f6d8a4bf34a added b
  |
  o  0:9092f1db7931 added a
  
  $ cd ..

Testing the --abort flag for `hg graft` which aborts and rollback to state
before the graft

  $ hg init abortgraft
  $ cd abortgraft
  $ for ch in a b c d; do echo $ch > $ch; hg add $ch; hg ci -Aqm "added "$ch; done;

  $ hg up '.^^'
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved

  $ echo x > x
  $ hg ci -Aqm "added x"
  $ hg up '.^'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo foo > c
  $ hg ci -Aqm "added foo to c"

  $ hg log -GT "{rev}:{node|short} {desc}"
  @  5:36b793615f78 added foo to c
  |
  | o  4:863a25e1a9ea added x
  |/
  | o  3:9150fe93bec6 added d
  | |
  | o  2:155349b645be added c
  |/
  o  1:5f6d8a4bf34a added b
  |
  o  0:9092f1db7931 added a
  
  $ hg up 9150fe93bec6
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg abort
  abort: no interrupted graft to abort (abortflag !)
  abort: no operation in progress (abortcommand !)
  [20]

when stripping is required
  $ hg graft -r 4 -r 5
  grafting 4:863a25e1a9ea "added x"
  grafting 5:36b793615f78 "added foo to c" (tip)
  merging c
  warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ hg graft --continue --abort
  abort: cannot specify both --abort and --continue
  [10]

  $ hg graft --abort --stop
  abort: cannot specify both --abort and --stop
  [10]

  $ hg graft --abort --currentuser
  abort: cannot specify both --abort and --user
  [10]

  $ hg graft --abort --edit
  abort: cannot specify both --abort and --edit
  [10]

#if abortcommand
when in dry-run mode
  $ hg abort --dry-run
  graft in progress, will be aborted
#endif

  $ hg abort
  graft aborted
  working directory is now at 9150fe93bec6
  $ hg log -GT "{rev}:{node|short} {desc}"
  o  5:36b793615f78 added foo to c
  |
  | o  4:863a25e1a9ea added x
  |/
  | @  3:9150fe93bec6 added d
  | |
  | o  2:155349b645be added c
  |/
  o  1:5f6d8a4bf34a added b
  |
  o  0:9092f1db7931 added a
  
when stripping is not required
  $ hg graft -r 5
  grafting 5:36b793615f78 "added foo to c" (tip)
  merging c
  warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ hg abort
  graft aborted
  working directory is now at 9150fe93bec6
  $ hg log -GT "{rev}:{node|short} {desc}"
  o  5:36b793615f78 added foo to c
  |
  | o  4:863a25e1a9ea added x
  |/
  | @  3:9150fe93bec6 added d
  | |
  | o  2:155349b645be added c
  |/
  o  1:5f6d8a4bf34a added b
  |
  o  0:9092f1db7931 added a
  
when some of the changesets became public

  $ hg graft -r 4 -r 5
  grafting 4:863a25e1a9ea "added x"
  grafting 5:36b793615f78 "added foo to c" (tip)
  merging c
  warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ hg log -GT "{rev}:{node|short} {desc}"
  @  6:6ec71c037d94 added x
  |
  | %  5:36b793615f78 added foo to c
  | |
  | | o  4:863a25e1a9ea added x
  | |/
  o |  3:9150fe93bec6 added d
  | |
  o |  2:155349b645be added c
  |/
  o  1:5f6d8a4bf34a added b
  |
  o  0:9092f1db7931 added a
  
  $ hg phase -r 6 --public

  $ hg abort
  cannot clean up public changesets 6ec71c037d94
  graft aborted
  working directory is now at 6ec71c037d94

when we created new changesets on top of existing one

  $ hg up '.^^'
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo y > y
  $ hg ci -Aqm "added y"
  $ echo z > z
  $ hg ci -Aqm "added z"

  $ hg up 3
  1 files updated, 0 files merged, 3 files removed, 0 files unresolved
  $ hg log -GT "{rev}:{node|short} {desc}"
  o  8:637f9e9bbfd4 added z
  |
  o  7:123221671fd4 added y
  |
  | o  6:6ec71c037d94 added x
  | |
  | | o  5:36b793615f78 added foo to c
  | | |
  | | | o  4:863a25e1a9ea added x
  | | |/
  | @ |  3:9150fe93bec6 added d
  |/ /
  o /  2:155349b645be added c
  |/
  o  1:5f6d8a4bf34a added b
  |
  o  0:9092f1db7931 added a
  
  $ hg graft -r 8 -r 7 -r 5
  grafting 8:637f9e9bbfd4 "added z" (tip)
  grafting 7:123221671fd4 "added y"
  grafting 5:36b793615f78 "added foo to c"
  merging c
  warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ cd ..
  $ hg init pullrepo
  $ cd pullrepo
  $ cat >> .hg/hgrc <<EOF
  > [phases]
  > publish=False
  > EOF
  $ hg pull ../abortgraft --config phases.publish=False
  pulling from ../abortgraft
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 11 changesets with 9 changes to 8 files (+4 heads)
  new changesets 9092f1db7931:6b98ff0062dd (6 drafts)
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg up 9
  5 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo w > w
  $ hg ci -Aqm "added w" --config phases.publish=False

  $ cd ../abortgraft
  $ hg pull ../pullrepo
  pulling from ../pullrepo
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  new changesets 311dfc6cf3bf (1 drafts)
  (run 'hg heads .' to see heads, 'hg merge' to merge)

  $ hg abort
  new changesets detected on destination branch, can't strip
  graft aborted
  working directory is now at 6b98ff0062dd

  $ cd ..

============================
Testing --no-commit option:|
============================

  $ hg init nocommit
  $ cd nocommit
  $ echo a > a
  $ hg ci -qAma
  $ echo b > b
  $ hg ci -qAmb
  $ hg up -q 0
  $ echo c > c
  $ hg ci -qAmc
  $ hg log -GT "{rev}:{node|short} {desc}\n"
  @  2:d36c0562f908 c
  |
  | o  1:d2ae7f538514 b
  |/
  o  0:cb9a9f314b8b a
  

Check reporting when --no-commit used with non-applicable options:

  $ hg graft 1 --no-commit -e
  abort: cannot specify both --no-commit and --edit
  [10]

  $ hg graft 1 --no-commit --log
  abort: cannot specify both --no-commit and --log
  [10]

  $ hg graft 1 --no-commit -D
  abort: cannot specify both --no-commit and --currentdate
  [10]

Test --no-commit is working:
  $ hg graft 1 --no-commit
  grafting 1:d2ae7f538514 "b"

  $ hg log -GT "{rev}:{node|short} {desc}\n"
  @  2:d36c0562f908 c
  |
  | o  1:d2ae7f538514 b
  |/
  o  0:cb9a9f314b8b a
  

  $ hg diff
  diff -r d36c0562f908 b
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +b

Prepare wrdir to check --no-commit is resepected after --continue:

  $ hg up -qC
  $ echo A>a
  $ hg ci -qm "A in file a"
  $ hg up -q 1
  $ echo B>a
  $ hg ci -qm "B in file a"
  $ hg log -GT "{rev}:{node|short} {desc}\n"
  @  4:2aa9ad1006ff B in file a
  |
  | o  3:09e253b87e17 A in file a
  | |
  | o  2:d36c0562f908 c
  | |
  o |  1:d2ae7f538514 b
  |/
  o  0:cb9a9f314b8b a
  

  $ hg graft 3 --no-commit
  grafting 3:09e253b87e17 "A in file a"
  merging a
  warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

Resolve conflict:
  $ echo A>a
  $ hg resolve --mark
  (no more unresolved files)
  continue: hg graft --continue

  $ hg graft --continue
  grafting 3:09e253b87e17 "A in file a"
  $ hg log -GT "{rev}:{node|short} {desc}\n"
  @  4:2aa9ad1006ff B in file a
  |
  | o  3:09e253b87e17 A in file a
  | |
  | o  2:d36c0562f908 c
  | |
  o |  1:d2ae7f538514 b
  |/
  o  0:cb9a9f314b8b a
  
  $ hg diff
  diff -r 2aa9ad1006ff a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -B
  +A

  $ hg up -qC

Check --no-commit is resepected when passed with --continue:

  $ hg graft 3
  grafting 3:09e253b87e17 "A in file a"
  merging a
  warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

Resolve conflict:
  $ echo A>a
  $ hg resolve --mark
  (no more unresolved files)
  continue: hg graft --continue

  $ hg graft --continue --no-commit
  grafting 3:09e253b87e17 "A in file a"
  $ hg diff
  diff -r 2aa9ad1006ff a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -B
  +A

  $ hg log -GT "{rev}:{node|short} {desc}\n"
  @  4:2aa9ad1006ff B in file a
  |
  | o  3:09e253b87e17 A in file a
  | |
  | o  2:d36c0562f908 c
  | |
  o |  1:d2ae7f538514 b
  |/
  o  0:cb9a9f314b8b a
  
  $ hg up -qC

Test --no-commit when graft multiple revisions:
When there is conflict:
  $ hg graft -r "2::3" --no-commit
  grafting 2:d36c0562f908 "c"
  grafting 3:09e253b87e17 "A in file a"
  merging a
  warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
  abort: unresolved conflicts, can't continue
  (use 'hg resolve' and 'hg graft --continue')
  [1]

  $ echo A>a
  $ hg resolve --mark
  (no more unresolved files)
  continue: hg graft --continue
  $ hg graft --continue
  grafting 3:09e253b87e17 "A in file a"
  $ hg diff
  diff -r 2aa9ad1006ff a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -B
  +A
  diff -r 2aa9ad1006ff c
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +c

  $ hg log -GT "{rev}:{node|short} {desc}\n"
  @  4:2aa9ad1006ff B in file a
  |
  | o  3:09e253b87e17 A in file a
  | |
  | o  2:d36c0562f908 c
  | |
  o |  1:d2ae7f538514 b
  |/
  o  0:cb9a9f314b8b a
  
  $ hg up -qC

When there is no conflict:
  $ echo d>d
  $ hg add d -q
  $ hg ci -qmd
  $ hg up 3 -q
  $ hg log -GT "{rev}:{node|short} {desc}\n"
  o  5:baefa8927fc0 d
  |
  o  4:2aa9ad1006ff B in file a
  |
  | @  3:09e253b87e17 A in file a
  | |
  | o  2:d36c0562f908 c
  | |
  o |  1:d2ae7f538514 b
  |/
  o  0:cb9a9f314b8b a
  

  $ hg graft -r 1 -r 5 --no-commit
  grafting 1:d2ae7f538514 "b"
  grafting 5:baefa8927fc0 "d" (tip)
  $ hg diff
  diff -r 09e253b87e17 b
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +b
  diff -r 09e253b87e17 d
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/d	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +d
  $ hg log -GT "{rev}:{node|short} {desc}\n"
  o  5:baefa8927fc0 d
  |
  o  4:2aa9ad1006ff B in file a
  |
  | @  3:09e253b87e17 A in file a
  | |
  | o  2:d36c0562f908 c
  | |
  o |  1:d2ae7f538514 b
  |/
  o  0:cb9a9f314b8b a
  
  $ cd ..