After bzr pump, "next" pipelines have a broken dirstate (got IndexError: list index out of range)

[Natalia Bidart]

The following scenario makes it possible to reproduce the IndexError:

# branch lp:bzr-pipeline
nessita@dali:~/projects/test$ bzr branch lp:bzr-pipeline trunk
Branched 214 revisions.

# create a light weight checkout of trunk
nessita@dali:~/projects/test$ bzr checkout --lightweight trunk/ current

# create a pipeline to work with in the light checkout
nessita@dali:~/projects/test$ cd current/
nessita@dali:~/projects/test/current$ bzr pipes
* trunk
nessita@dali:~/projects/test/current$ bzr switch -b part-1
Tree is up to date at revision 214.
Switched to branch: /home/nessita/projects/test/part-1/

# make some modifications to commands.py and commit those changes
nessita@dali:~/projects/test/current$ bzr ci -m 'Some pep8 fixes.'
Committing to: /home/nessita/projects/test/part-1/
modified check-release.py
modified commands.py
Committed revision 215.

# push the changes somewhere
nessita@dali:~/projects/test/current$ bzr push lp:~nataliabidart/+junk/test-part-1
Created new branch.

# add a pipe
nessita@dali:~/projects/test/current$ bzr add-pipe part-2
Tree is up to date at revision 215.
Created and switched to pipe "part-2".

# make some modifications to loom.py and commit them
nessita@dali:~/projects/test/current$ bzr ci -m 'Some other pep8 fixes.'
Committing to: /home/nessita/projects/test/part-2/
modified loom.py
Committed revision 216.

# go to the previous pipe
nessita@dali:~/projects/test/current$ bzr switch-pipe :prev
Switched from "part-2" to "part-1".

# make some extra modifications to commands.py and commit
nessita@dali:~/projects/test/current$ bzr ci -m 'Fixed all pep8 errors in command.py.'
Committing to: /home/nessita/projects/test/part-1/
modified commands.py
Committed revision 216.

# push the latest changes
nessita@dali:~/projects/test/current$ bzr push
Using saved push location: bzr+ssh://bazaar.launchpad.net/~nataliabidart/+junk/test-part-1/
Pushed up to revision 216.

# pump the changes to the next pipe
nessita@dali:~/projects/test/current$ bzr pump

# switch to the next pipe
nessita@dali:~/projects/test/current$ bzr switch-pipe :next
Switched from "part-1" to "part-2".
nessita@dali:~/projects/test/current$ bzr log --limit 1 --line
217: Natalia B. Bidart 2012-07-30 [merge] Merged part-1 into part-2.

# boom, dirstate is broken
nessita@dali:~/projects/test/current$ bzr st
bzr: ERROR: exceptions.IndexError: list index out of range

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 920, in exception_to_return_code
    return the_callable(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 1131, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 673, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 695, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 136, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 166, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 1148, in ignore_pipe
    result = func(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/builtins.py", line 420, in run
    classify=not no_classify)
  File "/usr/lib/python2.7/dist-packages/bzrlib/status.py", line 175, in show_tree_status
    classify=classify)
  File "/usr/lib/python2.7/dist-packages/bzrlib/status.py", line 75, in report_changes
    want_unversioned=want_unversioned)
  File "/usr/lib/python2.7/dist-packages/bzrlib/tree.py", line 103, in changes_from
    want_unversioned=want_unversioned,
  File "/usr/lib/python2.7/dist-packages/bzrlib/decorators.py", line 155, in read_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/tree.py", line 1050, in compare
    want_unversioned=want_unversioned)
  File "/usr/lib/python2.7/dist-packages/bzrlib/delta.py", line 129, in _compare_trees
    want_unversioned=want_unversioned):
  File "_dirstate_helpers_pyx.pyx", line 1465, in bzrlib._dirstate_helpers_pyx.ProcessEntryC.__next__
  File "_dirstate_helpers_pyx.pyx", line 1577, in bzrlib._dirstate_helpers_pyx.ProcessEntryC._iter_next
  File "_dirstate_helpers_pyx.pyx", line 1155, in bzrlib._dirstate_helpers_pyx.ProcessEntryC._process_entry
IndexError: list index out of range

You can report this problem to Bazaar's developers by running
    apport-bug /var/crash/bzr.1000.2012-07-30T15:07.crash
if a bug-reporting window does not automatically appear.
nessita@dali:~/projects/test/current$

[Natalia Bidart (nataliabidart)]

Is worth noting that running:

nessita@dali:~/projects/test/current$ bzr repair-workingtree --force

fixes the error, until next bzr pump is run in previous pipes.

[Martin Packman (gz)]

Minimised version of those instructions:

bzr init trunk
bzr commit --unchanged -m"r1 in trunk" trunk
bzr checkout --lightweight trunk current
cd current
bzr pipes
bzr switch -b part-1
bzr add-pipe part-2
bzr commit --unchanged -m"r2 in part-2"
bzr switch-pipe :prev
bzr commit --unchanged -m"r2 in part-1"
bzr pump
bzr switch-pipe :next
bzr st

[Alberto Donato (ack)]

This happens with versions in Zesty too