bzr does not work with python2.6

[Felix Möller]

I am trying to use bzr on openSUSE but it does not work at all. The problem is probably my python version. I have

$ python --version
Python 2.6b3

I have tried bzr 1.6.1 and 1.7rc1.

Initially they both fail with:
$ ../install/bin/bzr init
/home/fm/bzr-1.6.1/install/lib/python2.6/site-packages/bzrlib/lazy_import.py:195:
DeprecationWarning: the sha module is deprecated; use the hashlib module
instead
  module = __import__(module_python_path, scope, scope, [])
bzr: ERROR: exceptions.TypeError: object.__init__() takes no parameters

After:
--- /home/fm/bzr-1.6.1/install/lib/python2.6/site-packages/bzrlib/transport/__init__.py 2008-09-12 20:09:55.000000000 +0200
+++ ../build/lib.linux-i686-2.6/bzrlib/transport/__init__.py 2008-09-05 22:12:59.000000000 +0200
@@ -293,7 +293,7 @@
     _bytes_to_read_before_seek = 0

     def __init__(self, base):
- super(Transport, self).__init__()
+ super(Transport, self).__init__(base=base)
         self.base = base

     def _translate_error(self, e, path, raise_generic=True):

this error is gone.

After that I get
fm@macbook:~/bzr-1.6.1/dir> ../install/bin/bzr ci
/home/fm/bzr-1.6.1/install/lib/python2.6/site-packages/bzrlib/lazy_import.py:195: DeprecationWarning: the sha module is deprecated; use the hashlib module instead
  module = __import__(module_python_path, scope, scope, [])
/home/fm/bzr-1.6.1/install/lib/python2.6/site-packages/bzrlib/lazy_import.py:195: DeprecationWarning: the md5 module is deprecated; use hashlib instead
  module = __import__(module_python_path, scope, scope, [])
Committing to: /home/fm/bzr-1.6.1/dir/
bzr: ERROR: exceptions.ImportError: cannot import name U32

This is caused by http://svn.python.org/view/python/trunk/Lib/gzip.py?rev=61821&r1=61813&r2=61821 ...

So what is the solution for that?

[John A Meinel (jameinel)]

Thanks for reporting this. I'll put up some patches for it. We don't really *need* U32, though I'm surprised they deleted the function completely.

I don't know that this will fix everything, but if you want to keep trying, it would be nice to try and get bzr to work with python 2.6. I don't think the changes will make 1.7 final, but we can try and get something nicer for 1.8.

[John A Meinel (jameinel)]

For now, I've put together the attached patch

[Felix Möller (felix-derklecks)]

Thanks for the quick patch, now I get:

fm@macbook:~/bzr-1.7rc1/dir> ../install/bin/bzr init
/home/fm/bzr-1.7rc1/install/lib/python2.6/site-packages/bzrlib/lazy_import.py:195: DeprecationWarning: the sha module is deprecated; use the hashlib module instead
  module = __import__(module_python_path, scope, scope, [])
bzr: ERROR: exceptions.ImportError: failed to load bzrlib.repofmt.weaverepo.RepositoryFormat7: cannot import name LOWU32

Traceback (most recent call last):
  File "install/lib/python2.6/site-packages/bzrlib/commands.py", line 857, in run_bzr_catch_errors
  File "install/lib/python2.6/site-packages/bzrlib/commands.py", line 797, in run_bzr
  File "install/lib/python2.6/site-packages/bzrlib/commands.py", line 499, in run_argv_aliases
  File "install/lib/python2.6/site-packages/bzrlib/builtins.py", line 1340, in run
  File "install/lib/python2.6/site-packages/bzrlib/info.py", line 346, in show_bzrdir_info
  File "install/lib/python2.6/site-packages/bzrlib/info.py", line 361, in show_component_info
  File "install/lib/python2.6/site-packages/bzrlib/info.py", line 449, in describe_format
  File "install/lib/python2.6/site-packages/bzrlib/bzrdir.py", line 2768, in make_bzrdir
  File "install/lib/python2.6/site-packages/bzrlib/bzrdir.py", line 2720, in helper
  File "install/lib/python2.6/site-packages/bzrlib/bzrdir.py", line 2705, in _load
ImportError: failed to load bzrlib.repofmt.weaverepo.RepositoryFormat7: cannot import name LOWU32

[Felix Möller (felix-derklecks)]

I think you might be wrong with your U32. Have a look at http://svn.python.org/view/python/trunk/Lib/gzip.py?rev=61646&view=markup ...

I have created a new patch for the U32 issue and added LOWU32 too.

[Vincent Ladeuil (vila)]

It's quite old but:
https://code.launchpad.net/~vila/bzr/bzr.python26

was my last attempt to run bzr with python-2.6.

I needed it to test the ssl module, which has since been provided for python-2.5 and 2.4 (as a separate package though).

Anyway, on 2007-11-20 (date of the last commit), I said:

    Ugly bug marking, but test suite passing for python2.6. Since 2.6
    is still developed investigating now seems a waste.

I'd be happy to resurrect it.

[Felix Möller (felix-derklecks)]

Hi vila,

Looking at http://www.python.org/dev/peps/pep-0361/ it seems like python will be released in one month. The current openSUSE factory version already contains python 2.6 ...

python 2.6 RC 1 is due today so I think it is not a moving target anymore. I would be happy to test a patch from you.

Thanks

[Vincent Ladeuil (vila)]

    Felix> Looking at http://www.python.org/dev/peps/pep-0361/ it
    Felix> seems like python will be released in one month. The
    Felix> current openSUSE factory version already contains
    Felix> python 2.6 ...

    Felix> python 2.6 RC 1 is due today so I think it is not a moving target
    Felix> anymore.

Sure, my comment was made in November 2007...

    Felix> I would be happy to test a patch from you.

I'm looking into it but there are test failures and errors (with
a checkout of lp:python which is said to be what python-2.6 will
be):

Ran 13225 tests in 828.796s

FAILED (failures=33, errors=35, known_failure_count=8)
839 tests skipped
Missing feature 'FTPServer' skipped 94 tests.
Missing feature 'Internally performed glob expansion' skipped 5 tests.
Missing feature '_winreg' skipped 2 tests.
Missing feature 'attrib Windows command-line tool' skipped 1 tests.
Missing feature 'bzrlib._btree_serializer_c' skipped 1 tests.
Missing feature 'bzrlib._dirstate_helpers_c' skipped 23 tests.
Missing feature 'bzrlib._knit_load_data_c' skipped 25 tests.
Missing feature 'bzrlib._patiencediff_c' skipped 11 tests.
Missing feature 'bzrlib._readdir_pyx' skipped 1 tests.
Missing feature 'bzrlib._walkdirs_win32' skipped 9 tests.
Missing feature 'case-insensitive filesystem' skipped 1 tests.
tests failed

I've merged a recent bzr .dev and setup a new branch
(lp:~vila/bzr/py26bzr).

Your patch for U32 is correct (I did the same before seeing
yours).

But the behavior of __init__ has changed in an apparently very
subtle way which bites bzr hard.

Basically you can't apply your first patch (related to
super(Transport, self).__init__) because with python 2.5:

- it's not illegal to call object.__init__ with parameters

- it seems to call the next available __init__ when multiple
  inheritance is used.

In python 2.6, it fails to call object.__init__ if parameters are
specified but if you delete the parameters the call to __init__
for the next base class is wrong.

And that's only the first failing test. So in the short term,
you'd better look at how openSuse can tie python-2.5 as a
dependency for bzr.

bzr currently requires python 2.4 or 2.5, obviously we *will*
support 2.6, but we don't right now.

[Vincent Ladeuil (vila)]

Applying the patch attached to http://bugs.python.org/issue3879, and using at least revno 2943 from the lp:~vila/bzr/py26bzr/ makes the test suite pass.

[Vincent Ladeuil (vila)]

Note that since python-2.6 final has not been released, this branch should be considered as a work in progress.

[Vincent Ladeuil (vila)]

There was one remaining failure fixed by revno 2945 on lp:~vila/bzr/py26bzr.

There are also some deprecation warnings which seems minor enough to leave as is, waiting for a final version of python-2.6.

In the mean time, I intend to polish the patches a bit and submit them for review.

Also note that the patches were built againt a python-2.6RC1, no tests have been conducted against priori beta versions.