Colander

==================

- Added Polish translation, thanks to Jedrzej Nowak.

- Moved to Pylons Project GitHub (https://github.com/Pylons/colander).

- Add tox.ini for testing purposes.

- New API: ``colander.required``. Used as the marker value when a
``missing`` argument is left unspecified.

- Bug fix: if a ``title`` argument which is the empty string or ``None`` is
passed explicitly to a SchemaNode, it is no longer replaced by a title
computed from the name.

- Add SchemaNode.__contains__ to support "name in schema".

- SchemaNode deserialization now unconditionally calls the schema type's
``deserialize`` method to obtain an appstruct before attempting to
validate. Third party schema types should now return ``colander.null`` if
passed a ``colander.null`` value or another logically "empty" value as a
cstruct during ``deserialize``.

==================

- When ``colander.null`` was unpickled, the reference created during
unpickling was *not* a reference to the singleton but rather a new instance
of the ``colander._null`` class. This was unintentional, because lots of
code checks for ``if x is colander.null``, which will fail across pickling
and unpickling. Now the reference created when ``colander.null`` is
pickled is unpickled as the singleton itself.

=================

- SchemaNode constructor now accepts arbitrary keyword arguments. It
sets any unknown values within the ``**kw`` sequence as attributes
of the node object.

- Added Spanish locale: thanks to Douglas Cerna for the translations!

- If you use a schema with deferred ``validator``, ``missing`` or
``default`` attributes, but you use it to perform serialization and
deserialization without calling its ``bind`` method:

- If ``validator`` is deferred, no validation will be performed.

- If ``missing`` is deferred, the field will be considered *required*.

- If ``default`` is deferred, the serialization default will be
assumed to be ``colander.null``.

- Undocumented internal API for all type objects: ``flatten``.
External type objects should now inherit from
``colander.SchemaType`` to get a default implementation.

=================

- Docstring fixes to ``colander.SchemaNode`` (``missing`` is not the
``null`` value when required, it's a special marker value).

- The concept of "schema binding" was added, which allows for a more
declarative-looking spelling of schemas and schema nodes which have
dependencies on values available after the schema has already been
fully constructed. See the new narrative chapter in the
documentation entitled "Schema Binding".

- The interface of ``colander.SchemaNode`` has grown a ``__delitem__``
method. The ``__iter__``, and ``__getitem__`` methods have now also
been properly documented.

==================

- The title of a schema node now defaults to a titleization of the
``name``. Underscores in the ``name`` are replaced with empty
strings and the first letter of every resulting word is capitalized.
Previously the ``name`` was not split on underscores, and the
entirety of the ``name`` was capitalized.

- A method of the ``colander.Invalid`` exception named ``messages``
was added. It returns an iterable of error messages using the
``msg`` attribute of its related exception node. If the ``msg``
attribute is iterable, it is returned. If it is not iterable, a
single-element list containing the ``msg`` value is returned.

==================

- Add an ``colander.SchemaNode.__iter__`` method, which iterates over
the children nodes of a schema node.

- The constructor of a ``colander.SchemaNode`` now accepts a
``widget`` keyword argument, for use by Deform (it is not used
internally).