Fixes#966
* As a preallocation optimization, ``list()`` calls ``__len__`` on its
parameter if it's available
* Before Python 2.7.4, WeakSet has a bug[0] where ``len()`` is unsafe: it is
done by iteration and weakrefs may be removed from the underlying set during
the iteration
As a result, the safety feature of listifying a WeakSet to ensure we have
strong refs on all items during iteration may blow up.
Wrapping the weakset in a ``iter()`` makes ``__len__()`` invisible and ensures
we're within the IterationGuard[1].
Which now that I think about it means we *should* be able to safely iterate
weaksets in the first place and may not have needed to listify them...
[0] http://bugs.python.org/issue14159
[1] http://hg.python.org/cpython/file/b6acfbe2bdbe/Lib/_weakrefset.py#l58
A squashed merge is required as the conversion of the apiculture branch from
bzr to git was not correctly done. The git history contains irrelevant blobs
and commits. This branch brings a lot of changes and fixes, too many to list
exhaustively.
- New orm api, objects are now used instead of ids
- Environements to encapsulates cr uid context while maintaining backward compatibility
- Field compute attribute is a new object oriented way to define function fields
- Shared browse record cache
- New onchange protocol
- Optional copy flag on fields
- Documentation update
- Dead code cleanup
- Lots of fixes
Xavier Morel
Raphael Collet