Source code for azure.core._enum_meta

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from enum import EnumMeta


class CaseInsensitiveEnumMeta(EnumMeta):
    """Enum metaclass to allow for interoperability with case-insensitive strings.

    Consuming this metaclass in an SDK should be done in the following manner:

    .. code-block:: python

        from enum import Enum
        from six import with_metaclass
        from azure.core import CaseInsensitiveEnumMeta

        class MyCustomEnum(with_metaclass(CaseInsensitiveEnumMeta, str, Enum)):
            FOO = 'foo'
            BAR = 'bar'

    """

    def __getitem__(cls, name):
        # disabling pylint bc of pylint bug https://github.com/PyCQA/astroid/issues/713
        return super(CaseInsensitiveEnumMeta, cls).__getitem__(name.upper())  # pylint: disable=no-value-for-parameter

    def __getattr__(cls, name):
        """Return the enum member matching `name`
        We use __getattr__ instead of descriptors or inserting into the enum
        class' __dict__ in order to support `name` and `value` being both
        properties for enum members (which live in the class' __dict__) and
        enum members themselves.
        """
        try:
            return cls._member_map_[name.upper()]
        except KeyError:
            raise AttributeError(name)