[Zope-dev] Object schema field validation

29 Nov 2009

      I stumbled upon a problem with Object schema field validation. The problem occurs, e.g., if the the Object field's schema itself contains a Choice field with a dynamically computed vocabulary. For the latter to validate correctly the field must be bound to the instance. But the Object field validation code in zope.schema._fields._validate_fields validates the attributes of the Object field instance without binding them first:

def _validate_fields(schema, value, errors=None):
    ...
            try:
                attribute = schema[name]
                if IField.providedBy(attribute):
                    # validate attributes that are fields
                    attribute.validate(getattr(value, name))
            except ValidationError, error:
                ...

Replacing the line

    attribute.validate(getattr(value, name))

with

    field = attribute.bind(value)
    field.validate(getattr(value, name))

fixes the problem.

Looks like a bug to me.

Regards,
Markus Kemmerling