Class ValueItems

pydantic/v1/utils.py:483–626

Class for more convenient calculation of excluded or included fields on values.

class ValueItems(Representation):
    """
    Class for more convenient calculation of excluded or included fields on values.
    """

    __slots__ = ('_items', '_type')

    def __init__(self, value: Any, items: Union['AbstractSetIntStr', 'MappingIntStrAny']) -> None:
        items = self._coerce_items(items)

        if isinstance(value, (list, tuple)):
            items = self._normalize_indexes(items, len(value))

        self._items: 'MappingIntStrAny' = items

    def is_excluded(self, item: Any) -> bool:
        """
        Check if item is fully excluded.

        :param item: key or index of a value
        """
        return self.is_true(self._items.get(item))

    def is_included(self, item: Any) -> bool:
        """
        Check if value is contained in self._items

        :param item: key or index of value
        """
        return item in self._items

    def for_element(self, e: 'IntStr') -> Optional[Union['AbstractSetIntStr', 'MappingIntStrAny']]:
        """
        :param e: key or index of element on value
        :return: raw values for element if self._items is dict and contain needed element
        """

        item = self._items.get(e)
        return item if not self.is_true(item) else None

    def _normalize_indexes(self, items: 'MappingIntStrAny', v_length: int) -> 'DictIntStrAny':
        """
        :param items: dict or set of indexes which will be normalized
        :param v_length: length of sequence indexes of which will be

        >>> self._normalize_indexes({0: True, -2: True, -1: True}, 4)
        {0: True, 2: True, 3: True}
        >>> self._normalize_indexes({'__all__': True}, 4)
        {0: True, 1: True, 2: True, 3: True}
        """

        normalized_items: 'DictIntStrAny' = {}
        all_items = None
        for i, v in items.items():
            if not (isinstance(v, Mapping) or isinstance(v, AbstractSet) or self.is_true(v)):
                raise TypeError(f'Unexpected type of exclude value for index "{i}" {v.__class__}')
            if i == '__all__':
                all_items = self._coerce_value(v)