Application: gvSIG desktop » gvSIG scripting

"""Check non-iterators returned by __iter__ """

# pylint: disable=too-few-public-methods, missing-docstring, no-self-use

import six

class FirstGoodIterator(object):

    """ yields in iterator. """

    def __iter__(self):

        for index in range(10):

            yield index

class SecondGoodIterator(object):

    """ __iter__ and next """

    def __iter__(self):

        return self

    def __next__(self):

        """ Infinite iterator, but still an iterator """

        return 1

    def next(self):

        """Same as __next__, but for Python 2."""

        return 1

class ThirdGoodIterator(object):

    """ Returns other iterator, not the current instance """

    def __iter__(self):

        return SecondGoodIterator()

class FourthGoodIterator(object):

    """ __iter__ returns iter(...) """

    def __iter__(self):

        return iter(range(10))

class IteratorMetaclass(type):

    def __next__(cls):

        return 1

    def next(cls):

        return 2

@six.add_metaclass(IteratorMetaclass)

class IteratorClass(object):

    """Iterable through the metaclass."""

class FifthGoodIterator(object):

    """__iter__ returns a class which uses an iterator-metaclass."""

    def __iter__(self):

        return IteratorClass

class FileBasedIterator(object):

    def __init__(self, path):

        self.path = path

        self.file = None

    def __iter__(self):

        if self.file is not None:

            self.file.close()

        self.file = open(self.path)

        # self file has two infered values: None and <instance of 'file'>

        # we don't want to emit error in this case

        return self.file

class FirstBadIterator(object):

    """ __iter__ returns a list """

    def __iter__(self): # [non-iterator-returned]

        return []

class SecondBadIterator(object):

    """ __iter__ without next """

    def __iter__(self): # [non-iterator-returned]

        return self

class ThirdBadIterator(object):

    """ __iter__ returns an instance of another non-iterator """

    def __iter__(self): # [non-iterator-returned]

        return SecondBadIterator()

class FourthBadIterator(object):

    """__iter__ returns a class."""

    def __iter__(self): # [non-iterator-returned]

        return ThirdBadIterator