utils.py 文件源码

def _get_non_gfk_field(opts, name):
    """
    For historical reasons, the admin app relies on GenericForeignKeys as being
    "not found" by get_field(). This could likely be cleaned up.

    Reverse relations should also be excluded as these aren't attributes of the
    model (rather something like `foo_set`).
    """
    field = opts.get_field(name)
    if (field.is_relation and
            # Generic foreign keys OR reverse relations
            ((field.many_to_one and not field.related_model) or field.one_to_many)):
        raise FieldDoesNotExist()

    # Avoid coercing <FK>_id fields to FK
    if field.is_relation and not field.many_to_many and hasattr(field, 'attname') and field.attname == name:
        raise FieldIsAForeignKeyColumnName()

    return field