示例#1
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def test_is_instance_basetypes1():
    """
        Checks that values which should be instances of
        basic types are actually recognised as instances.
    """
    values = {
        bool: True,
        int: 1,
        float: 1.0,
        complex: 1.0j,
        str: "hello",
        bytes: b"hello",
        bytearray: bytearray(b"hello"),
        memoryview: memoryview(b"hello"),
        list: ["hello", 0],
        tuple: ("hello", 0),
        range: range(15),
        slice: slice(15),
        set: set(["hello", 0]),
        frozenset: frozenset(["hello", 0]),
        dict: {
            "str": "hello",
            "int": 0
        },
        type: str,
        None: None,
        Decimal: Decimal('1.0'),
    }
    for t, obj in values.items():
        assert is_instance(obj, t, failure_callback=failure_callback)
        assert is_instance(obj, Any, failure_callback=failure_callback)
示例#2
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def test_is_instance_namedtuple():
    """ Tests `is_instance` on namedtuples. """
    class NamedTupleExample1T(NamedTuple):
        # pylint:disable=all
        name: str
        value: int

    class NamedTupleExample2T(NamedTuple):
        # pylint:disable=all
        name: str
        value: int

    class ClassExampleT:
        # pylint:disable=all
        name: str
        value: int

        def __init__(self, name, value):
            self.name = name
            self.value = value

    t1 = NamedTupleExample1T("t1", 1)
    t2 = NamedTupleExample2T("t2", 1)
    c = ClassExampleT("c", 1)
    assert is_instance(t1,
                       NamedTupleExample1T,
                       failure_callback=failure_callback)
    assert not is_instance(
        t2, NamedTupleExample1T, failure_callback=failure_callback)
    assert not is_instance(
        c, NamedTupleExample1T, failure_callback=failure_callback)
    assert not is_instance(t1._replace(value="1"),
                           NamedTupleExample1T,
                           failure_callback=failure_callback)
示例#3
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def test_is_instance_optional():
    type_dict = {**BASE_TYPES, **COLLECTION_TYPES}
    for t in type_dict:
        if t in (Ellipsis, NotImplemented):
            continue
        assert is_instance(None, Optional[t])
        assert is_instance(type_dict[t], Optional[t])
def test_is_typed_dict_basic():
    """
        Tests that `typing.TypedDict` are identified correctly,
        while classes and `dict` are not.
    """
    class A(TypedDict):
        # pylint:disable=all
        name: List[str]
        value: Union[int, float]

    assert is_typed_dict(A, failure_callback=failure_callback)
    a = {"name": ["hi"], "value": 1.1}
    assert is_instance(a, A, failure_callback=failure_callback)
    a = {"name": 0, "value": 1.1}  # type:ignore
    assert not is_instance(a, A, failure_callback=failure_callback)
    a = {"name": ["hi"], "value": 1.1}

    class B:
        # pylint:disable=all
        name: List[str]

        def __init__(self, name: List[str]):
            self.name = name

    assert not is_typed_dict(0, failure_callback=failure_callback)
    assert not is_typed_dict(B, failure_callback=failure_callback)
    assert not is_typed_dict(dict, failure_callback=failure_callback)
    b = B(["hi"])
    assert not is_instance(b, A, failure_callback=failure_callback)
示例#5
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def test_is_instance_list():
    """ Tests `is_instance` on lists. """
    assert is_instance([], List[int], failure_callback=failure_callback)
    assert is_instance([0, 1, 2], List[int], failure_callback=failure_callback)
    assert not is_instance(
        (0, 1, 2), List[int], failure_callback=failure_callback)
    assert not is_instance(
        [0, 1, "2"], List[int], failure_callback=failure_callback)
    assert is_instance([0, 1, "2"],
                       List[Union[int, str]],
                       failure_callback=failure_callback)
示例#6
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def test_misc():
    assert is_instance(None, None)
    assert is_typecheckable(None)
    assert is_typecheckable(...)
    assert is_typecheckable(NotImplemented)
    assert is_typecheckable(Literal["s", 0, 1.2])
    try:
        assert is_instance("hi", "bye")
        assert False
    except TypeError:
        assert True
示例#7
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def _test_types(type_dict, inherit_dict):
    for t in type_dict:
        for s in type_dict:
            if t == s:
                assert is_instance(type_dict[s], t)
            elif s in inherit_dict and t in inherit_dict[s]:
                assert is_instance(type_dict[s], t)
            else:
                assert not is_instance(type_dict[s], t)
    for t in type_dict:
        assert is_instance(type_dict[t], object)
        assert is_instance(type_dict[t], Any)
示例#8
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def test_is_instance_tuple1():
    """ Tests `is_instance` on variadic tuples. """
    assert is_instance(tuple(),
                       Tuple[int, ...],
                       failure_callback=failure_callback)
    assert is_instance((0, 1, 2),
                       Tuple[int, ...],
                       failure_callback=failure_callback)
    assert not is_instance(
        [0, 1, 2], Tuple[int, ...], failure_callback=failure_callback)
    assert not is_instance(
        (0, 1, "2"), Tuple[int, ...], failure_callback=failure_callback)
    assert is_instance((0, 1, "2"),
                       Tuple[Union[int, str], ...],
                       failure_callback=failure_callback)
示例#9
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def to_json_obj(obj: Any, t: Any) -> Any:
    """ Converts an json encodable type to a json standard type. """
    # pylint:disable=invalid-name,too-many-return-statements,too-many-branches
    if not is_json_encodable(t):
        raise TypeError("Type %s is not json-encodable." % str(t))
    if not is_instance(obj, t):
        raise TypeError("Object %s is not of type %s" % (str(obj), str(t)))
    if t in JSON_BASE_TYPES:
        return obj
    if t in (None, type(None), ...):
        return None
    if is_namedtuple(t):
        field_types = getattr(t, "_field_types")
        json_dict = OrderedDict()  # type:ignore
        for field in field_types:
            json_dict[field] = to_json_obj(getattr(obj, field),
                                           field_types[field])
        return json_dict
    if hasattr(t, "__origin__") and hasattr(t, "__args__"):  # generics
        if t.__origin__ is Union:
            for s in t.__args__:
                if is_instance(obj, s):
                    return to_json_obj(obj, s)
            raise AssertionError(_UNREACHABLE_ERROR_MSG)  # pragma: no cover
        if t.__origin__ is Literal:
            return obj
        if t.__origin__ in (list, set, frozenset, deque):
            return [to_json_obj(x, t.__args__[0]) for x in obj]
        if t.__origin__ is tuple:
            if len(t.__args__) == 2 and t.__args__[1] is ...:  # pylint:disable=no-else-return
                return [to_json_obj(x, t.__args__[0]) for x in obj]
            else:
                return [
                    to_json_obj(x, t.__args__[i]) for i, x in enumerate(obj)
                ]
        if t.__origin__ in (dict, Mapping):
            return {
                field: to_json_obj(obj[field], t.__args__[1])
                for field in obj
            }
        if t.__origin__ is OrderedDict:
            new_ordered_dict = OrderedDict()  # type:ignore
            for field in obj:
                new_ordered_dict[field] = to_json_obj(obj[field],
                                                      t.__args__[1])
            return new_ordered_dict
    raise AssertionError(_UNREACHABLE_ERROR_MSG)  # pragma: no cover
示例#10
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def test_is_instance_typed_dict():
    """ Tests `is_instance` on namedtuples. """
    class NamedTupleExample1T(TypedDict, total=True):
        # pylint:disable=all
        name: str
        value: int

    class NamedTupleExample2T(TypedDict, total=False):
        # pylint:disable=all
        name: str = "hello"
        value: int

    class ClassExampleT(NamedTuple):
        # pylint:disable=all
        name: str
        value: int

    t1 = {"name": "t1", "value": 1}
    t2 = {"value": 1}
    t3 = {"name": "t3"}
    t4 = {"name": "t4", "value": "blah"}
    c = ClassExampleT("c", 1)
    assert is_instance(t1,
                       NamedTupleExample1T,
                       failure_callback=failure_callback)
    assert is_instance(t1,
                       NamedTupleExample2T,
                       failure_callback=failure_callback)
    assert not is_instance(
        t2, NamedTupleExample1T, failure_callback=failure_callback)
    assert is_instance(t2,
                       NamedTupleExample2T,
                       failure_callback=failure_callback)
    assert not is_instance(
        t3, NamedTupleExample1T, failure_callback=failure_callback)
    assert is_instance(t3,
                       NamedTupleExample2T,
                       failure_callback=failure_callback)
    assert not is_instance(
        t4, NamedTupleExample1T, failure_callback=failure_callback)
    assert not is_instance(
        t4, NamedTupleExample2T, failure_callback=failure_callback)
    assert not is_instance(
        c, NamedTupleExample1T, failure_callback=failure_callback)
    assert not is_instance(
        c, NamedTupleExample2T, failure_callback=failure_callback)
示例#11
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def test_is_instance_literal():
    type_dict = {**BASE_TYPES, **COLLECTION_TYPES}
    for t in type_dict:
        for s in type_dict:
            assert is_instance(type_dict[t], Literal[type_dict[t],
                                                     type_dict[s]])
            assert is_instance(type_dict[s], Literal[type_dict[t],
                                                     type_dict[s]])
    for t in type_dict:
        for s in type_dict:
            for u in type_dict:
                assert is_instance(
                    type_dict[t], Literal[type_dict[t], type_dict[s],
                                          type_dict[u]])
                assert is_instance(
                    type_dict[s], Literal[type_dict[t], type_dict[s],
                                          type_dict[u]])
                assert is_instance(
                    type_dict[u], Literal[type_dict[t], type_dict[s],
                                          type_dict[u]])
示例#12
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def test_is_instance_union():
    type_dict = {**BASE_TYPES, **COLLECTION_TYPES}
    for t in type_dict:
        if t in (Ellipsis, NotImplemented):
            continue
        for s in type_dict:
            if s in (Ellipsis, NotImplemented):
                continue
            assert is_instance(type_dict[t], Union[t, s])
            assert is_instance(type_dict[s], Union[t, s])
    for t in type_dict:
        if t in (Ellipsis, NotImplemented):
            continue
        for s in type_dict:
            if s in (Ellipsis, NotImplemented):
                continue
            for u in type_dict:
                if u in (Ellipsis, NotImplemented):
                    continue
                assert is_instance(type_dict[t], Union[t, s, u])
                assert is_instance(type_dict[s], Union[t, s, u])
                assert is_instance(type_dict[u], Union[t, s, u])
示例#13
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def test_is_namedtuple_basic():
    """
        Tests that `typing.NamedTuple` are identified correctly,
        while classes, `tuple` and `namedtuple` are not.
    """
    class A(NamedTuple):
        # pylint:disable=all
        name: List[str]
        value: Union[int, float]

    assert is_namedtuple(A, failure_callback=failure_callback)
    a = A(["hi"], 1.1)
    assert is_instance(a, A, failure_callback=failure_callback)
    a = A(0, 1.1)  # type:ignore
    assert not is_instance(a, A, failure_callback=failure_callback)
    a = A(["hi"], 1.1)

    class B:
        # pylint:disable=all
        name: List[str]

        def __init__(self, name: List[str]):
            self.name = name

    class Btuple(tuple):
        # pylint:disable=all
        name: List[str]

        def __init__(self, name: List[str]):
            self.name = name

    assert not is_namedtuple(0, failure_callback=failure_callback)
    assert not is_namedtuple(B, failure_callback=failure_callback)
    assert not is_namedtuple(Btuple, failure_callback=failure_callback)
    b = B(["hi"])
    assert not is_instance(b, A, failure_callback=failure_callback)
    C = namedtuple("C", ["name", "value"])
    assert not is_namedtuple(C, failure_callback=failure_callback)
示例#14
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def test_is_instance_union():
    """ Tests `is_instance` on unions and optional types. """
    assert is_instance(True, Optional[bool], failure_callback=failure_callback)
    assert is_instance(None, Optional[bool], failure_callback=failure_callback)
    assert not is_instance(
        "hi", Optional[bool], failure_callback=failure_callback)
    assert is_instance(1, Union[int, str], failure_callback=failure_callback)
    assert is_instance("hi",
                       Union[int, str],
                       failure_callback=failure_callback)
    assert not is_instance(
        range(15), Union[int, str], failure_callback=failure_callback)
示例#15
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def test_is_instance_literal():
    """ Tests `is_instance` on literal types. """
    assert is_instance("hi",
                       Literal["hi", 1, 2.5],
                       failure_callback=failure_callback)
    assert is_instance(1,
                       Literal["hi", 1, 2.5],
                       failure_callback=failure_callback)
    assert is_instance(2.5,
                       Literal["hi", 1, 2.5],
                       failure_callback=failure_callback)
    assert not is_instance(
        "hello", Literal["hi", 1, 2.5], failure_callback=failure_callback)
    assert not is_instance(
        2, Literal["hi", 1, 2.5], failure_callback=failure_callback)
    assert not is_instance(
        1.5, Literal["hi", 1, 2.5], failure_callback=failure_callback)
示例#16
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def from_json_obj(obj: Any, t: Type, cast_decimal: bool = True) -> Any:
    """
        Decodes a JSON object `obj` into an instance of a typecheckable type `t`.
        This method raises `TypeError` if type `t` is not JSON encodable according to `typing_json.encoding.is_json_encodable`.
        This method also raises `TypeError` if `obj` is not a valid JSON encoding for an instance of type `t`.

        Currently, this method acts as follows on an JSON object `obj` and a JSON-encodable type `t`:

        - if `t` is one of the JSON basic types `bool`, `float`, `str`, `NoneType`, `obj` must be an instance of the type an is returned unchanged;
        - if `t` is of the JSON basic type `int` and the `cast_decimal` parameter is set to `False`, `obj` must be an instance of `int` and is returned unchanged;
        - it `t` is of the JSON basic type `int` and the `cast_decimal` parameter is set to `True` (its default value), `obj` can be either an instance of `int`, in which case it is returned unchanged, or an instance of `decimal.Decimal` encoding an integer, in which case `int(obj)` is returned;
        - if `t` is of the JSON basic type `float` and the `cast_decimal` parameter is set to `False`, `obj` must be an instance of `int` or `float`, and `float(obj)` is returned;
        - it `t` is of the JSON basic type `float` and the `cast_decimal` parameter is set to `True` (its default value), `obj` can be either an instance of `int`, `float` or `decimal.Decimal`, in which case `float(obj)` is returned;
        - if `t` is `None`, used as an alias for `NoneType`, `obj` must be `None` and is returned unchanged;
        - if `t` is `decimal.Decimal` and the `cast_decimal` parameter is set to `False`, `obj` must be either a `decimal.Decimal`, an `int` or a `str` encoding a valid decimal, in which case `decimal.Decimal(obj)` is returned;
        v- if `t` is `decimal.Decimal` and the `cast_decimal` parameter is set to `True`, `obj` must be either a `decimal.Decimal`, an `int`, a `float` or a `str` encoding a valid decimal, in which case `decimal.Decimal(obj)` is returned;
        - if `t` is an enumeration, `obj` must be a key in the dictionary `t.__members__` of names for the enumeration constants, in which case `t.__members__[obj]` is returned;
        - if `t` is a namedtuple (according to `typing_json.typechecking.is_namedtuple`), see below;
        - if `t` is a namedtuple (according to `typing_json.typechecking.is_typed_dict`), see below;
        - if `t` is `typing.Union` or `typing.Optional`, try to decoded `obj` using the generic type arguments one after the other, until a suitable one is found;
        - if `t` is `typing_extensions.Literal`, check that `obj` is one of the literals and return it unaltered;
        - if `t` is `typing.List`, check that `obj` is a list and return a list with recursively JSON-decoded elements of `obj` in it;
        - if `t` is `typing.Tuple`, check that `obj` is a list and return a tuple with recursively JSON-decoded elements of `obj` in it;
        - if `t` is `typing.Deque`, check that `obj` is a list and return a deque with recursively JSON-decoded elements of `obj` in it;
        - if `t` is `typing.Set`, check that `obj` is a list and return a set with recursively JSON-decoded elements of `obj` in it;
        - if `t` is `typing.FrozenSet`, check that `obj` is a list and return a frozenset with recursively JSON-decoded elements of `obj` in it;
        - if `t` is `typing.Dict` or `typing.Mapping`, check that `obj` is a dict and return a dict with recursively JSON-decoded keys and values from `obj` (first parsing the keys from strings in all those cases where `typing_json.encoding.to_json_obj` would have stringified them);
        - if `t` is `typing.OrderedDict`, check that `obj` is a `collections.OrderedDict` and return a `collections.OrderedDict` with recursively JSON-decoded keys and values from `obj` (first parsing the keys from strings in all those cases where `typing_json.encoding.to_json_obj` would have stringified them);

        If `t` is a namedtuple (according to `typing_json.typechecking.is_namedtuple`), `obj` must be a dictionary (not necessarily ordered, although namedtuple are JSON-encoded as such).
        The keys for the dictionary must form a subset of all field names for the namedtuple `t`, including at least all names of fields without default value.
        An instance of `t` is then constructed (and returned) by assigning to fields having names in the dictionary the JSON decoding of the corresponding values in the dictionary, and to all other fields the default values specified by `t`.

        As an exception to the above rule, decoding of namedtuples is allowed from lists of values, in the same order as the namedtuple fields they are to be assigned to.
        Missing values are allowed at the end and are filled with default field values.
        No excess values are allowed.
        This is to support the default `json` library behaviour on namedtuples, encoded as lists of field values.

        If `t` is a typed dict (according to `typing_json.typechecking.is_typed_dict`), `obj` must be a dictionary (not necessarily ordered).
        The keys for the dictionary must form a subset of all keys for the typed dict `t`; if `t` is total, then all keys must be presend.
        An instance of `t` is then constructed (and returned) by assigning to keys having names in the dictionary the JSON decoding of the corresponding values in the dictionary.

        (Version 0.1.3)
    """
    # pylint: disable = too-many-branches, too-many-statements, too-many-return-statements
    trace: List[str] = []

    def failure_callback(message: str) -> None:
        trace.append(message)

    if not is_json_encodable(t, failure_callback=failure_callback):
        # Argument `t` must be JSON encodable.
        raise TypeError("Type %s is not json-encodable. Trace:\n%s" %
                        (str(t), "\n".join(trace)))
    if t in JSON_BASE_TYPES:
        # JSON basic types are returned unaltered, with the exception of casting `Decimal` to `int`/`float` if `cast_decimal` is `True`.
        if t == int and cast_decimal and isinstance(
                obj, Decimal) and obj == obj.to_integral_value():
            return int(obj)
        if t == float and cast_decimal and isinstance(obj, Decimal):
            return float(obj)
        if t == float and isinstance(
                obj, int) and obj is not True and obj is not False:
            return float(obj)
        if not is_instance(obj, t, cast_decimal=cast_decimal):
            raise TypeError("Object %s is not of json basic type t=%s." %
                            (short_str(obj), str(t)))
        return obj
    if t in (None, type(None)):
        # The only value of `NoneType` is `None`, which is returned unaltered.
        if obj is not None:
            raise TypeError("Object %s is not None (t=%s)." %
                            (short_str(obj), str(t)))
        return None
    if t == Decimal:
        # Instances of `decimal.Decimal` are decoded from `int` or `string`, as well as from `float` if `cast_decimal` is `True`
        try:
            if isinstance(
                    obj,
                (int, str, Decimal)) and obj is not True and obj is not False:
                return Decimal(obj)
            if cast_decimal and isinstance(
                    obj, float) and obj is not True and obj is not False:
                return Decimal(obj)
        except InvalidOperation:
            ...
        raise TypeError("Object %s is not decimal.Decimal (t=%s)." %
                        (short_str(obj), str(t)))
    if isinstance(t, EnumMeta):
        # For enumerations, use the `t.__members__` dictionary to convert the string name into an enumeration value.
        if not isinstance(obj, str):
            raise TypeError("Object %s is not a string (t=%s)." %
                            (short_str(obj), str(t)))
        if obj not in t.__members__:  # type: ignore
            raise TypeError(
                "Object %s is not the string of a value of the enum (t=%s)." %
                (short_str(obj), str(t)))
        return t.__members__[obj]  # type: ignore # pylint:disable=protected-access
    if is_namedtuple(t):
        fields = getattr(t, "_fields")
        field_types = getattr(t, "_field_types")
        field_defaults = getattr(t, "_field_defaults")
        return _from_json_obj_namedtuple(obj,
                                         t,
                                         fields,
                                         field_types,
                                         field_defaults,
                                         cast_decimal=cast_decimal)
    if is_typed_dict(t):
        # Typed dicts are encoded as ordered dictionaries, with their fields as keys and the JSON-encoded field values as corresponding values.
        field_types = getattr(t, "__annotations__")
        total = getattr(t, "__total__")
        if not isinstance(obj, (dict, OrderedDict)):
            raise TypeError("Object %s is not dict or OrderedDict (t=%s)." %
                            (short_str(obj), str(t)))
        converted_dict = dict()  # type:ignore
        for field, field_type in field_types.items():
            if total and field not in obj:
                raise TypeError(
                    "Key %s missing from object %s (typed dict is total, t=%s)"
                    % (field, short_str(obj), str(t)))
            if field in obj:
                converted_dict[field] = from_json_obj(
                    obj[field], field_type, cast_decimal=cast_decimal)
        for field in obj:
            if field not in field_types:
                raise TypeError(
                    "Extra field %s found when decoding object. (t=%s)." %
                    (field, str(t)))
        return converted_dict
    if hasattr(t, "__origin__") and hasattr(t, "__args__"):
        # `typing` generics
        if t.__origin__ is Union:
            # For `typing.Union` (and `typing.Optional`), attempt to decode the value using the generic type arguments in sequence
            for s in t.__args__:
                try:
                    return_val = from_json_obj(obj,
                                               s,
                                               cast_decimal=cast_decimal)
                    # assert is_instance(return_val, t, cast_decimal=cast_decimal)
                    return return_val
                except TypeError:
                    continue
            raise TypeError(
                "Object %s is not convertible to any of the types in %s." %
                (short_str(obj), str(t)))
        if t.__origin__ is Literal:
            # for `typing_extensions.Literal`, check that the object is an instance of `t` and then return it unaltered
            trace = []
            if not is_instance(obj,
                               t,
                               failure_callback=failure_callback,
                               cast_decimal=cast_decimal):
                raise TypeError("Object %s is not allowed (t=%s). Trace:\n%s" %
                                (short_str(obj), str(t), "\n".join(trace)))
            return obj
        if t.__origin__ is list:
            # for `typing.List`, expect a list and return a list with recursively JSON-decoded elements
            if not isinstance(obj, list):
                raise TypeError("Object %s is not list (t=%s)." %
                                (short_str(obj), str(t)))
            return_val = list(
                _from_json_obj_iterator(obj,
                                        t.__args__[0],
                                        cast_decimal=cast_decimal))
            # assert is_instance(return_val, t, cast_decimal=cast_decimal)
            return return_val
        if t.__origin__ is deque:
            # for `typing.Deque`, expect a list and return a deque with recursively JSON-decoded elements
            if not isinstance(obj, list):
                raise TypeError("Object %s is not list (t=%s)." %
                                (short_str(obj), str(t)))
            return_val = deque(
                _from_json_obj_iterator(obj,
                                        t.__args__[0],
                                        cast_decimal=cast_decimal))
            # assert is_instance(return_val, t, cast_decimal=cast_decimal)
            return return_val
        if t.__origin__ is set:
            # for `typing.Set`, expect a list and return a set with recursively JSON-decoded elements
            if not isinstance(obj, list):
                raise TypeError("Object %s is not list (t=%s)." %
                                (short_str(obj), str(t)))
            return_val = set(
                _from_json_obj_iterator(obj,
                                        t.__args__[0],
                                        cast_decimal=cast_decimal))
            # assert is_instance(return_val, t, cast_decimal=cast_decimal)
            return return_val
        if t.__origin__ is frozenset:
            # for `typing.FrozenSet`, expect a list and return a frozenset with recursively JSON-decoded elements
            if not isinstance(obj, list):
                raise TypeError("Object %s is not list (t=%s)." %
                                (short_str(obj), str(t)))
            return_val = frozenset(
                _from_json_obj_iterator(obj,
                                        t.__args__[0],
                                        cast_decimal=cast_decimal))
            # assert is_instance(return_val, t, cast_decimal=cast_decimal)
            return return_val
        if t.__origin__ is tuple:
            # for `typing.Tuple`, expect a list and return a tuple with recursively JSON-decoded elements
            if not isinstance(obj, list):
                raise TypeError("Object %s is not list (t=%s)." %
                                (short_str(obj), str(t)))
            if len(t.__args__) == 2 and t.__args__[1] is ...:  # pylint:disable=no-else-return
                return_val = tuple(
                    _from_json_obj_iterator(obj,
                                            t.__args__[0],
                                            cast_decimal=cast_decimal))
                # assert is_instance(return_val, t, cast_decimal=cast_decimal)
                return return_val
            else:
                if len(obj) != len(t.__args__):
                    raise TypeError("List %s is of incorrect length (t=%s)." %
                                    (short_str(obj), str(t)))
                return_val = tuple(
                    from_json_obj(x, t.__args__[i], cast_decimal=cast_decimal)
                    for i, x in enumerate(obj))
                # assert is_instance(return_val, t, cast_decimal=cast_decimal)
                return return_val
        if t.__origin__ in (dict, Mapping):
            # for `typing.Dict` and `typing.Mapping`, expect a dict and return a dict with recursively JSON-decoded values and keys (parsing keys from strings in all those cases where they would have been stringified)
            if not isinstance(obj, (dict, OrderedDict)):
                raise TypeError(
                    "Object %s is not dict or OrderedDict (t=%s)." %
                    (short_str(obj), str(t)))
            converted_dict = dict()  # type:ignore
            for field in obj:
                if t.__args__[0] in JSON_BASE_TYPES:
                    if not is_instance(
                            field, t.__args__[0], cast_decimal=cast_decimal):
                        raise TypeError(
                            "Object key %s is not of json basic type %s (t=%s)."
                            % (field, str(t.__args__[0]), str(t)))
                    converted_field = field
                elif isinstance(t.__args__[0], EnumMeta) or hasattr(
                        t.__args__[0],
                        "__origin__") and t.__args__[0].__origin__ is Literal:
                    converted_field = from_json_obj(field,
                                                    t.__args__[0],
                                                    cast_decimal=cast_decimal)
                else:
                    converted_field = from_json_obj(json.loads(field),
                                                    t.__args__[0],
                                                    cast_decimal=cast_decimal)
                converted_dict[converted_field] = from_json_obj(
                    obj[field], t.__args__[1], cast_decimal=cast_decimal)
            # assert is_instance(converted_dict, t, cast_decimal=cast_decimal)
            return converted_dict
        if t.__origin__ is OrderedDict:
            # for `typing.OrderedDict`, expect a `collections.OrderedDict` and return an ordered dict with recursively JSON-decoded values and keys (parsing keys from strings in all those cases where they would have been stringified)
            if not isinstance(obj, OrderedDict):
                raise TypeError("Object %s is not OrderedDict (t=%s)." %
                                (short_str(obj), str(t)))
            converted_dict = OrderedDict()  # type:ignore
            for field in obj:
                if t.__args__[0] in JSON_BASE_TYPES:
                    if not isinstance(field, t.__args__[0]):
                        raise TypeError(
                            "Object key %s not of json basic type %s (t=%s)." %
                            (field, str(t.__args__[0]), str(t)))
                    converted_field = field
                elif isinstance(t.__args__[0], EnumMeta) or hasattr(
                        t.__args__[0],
                        "__origin__") and t.__args__[0].__origin__ is Literal:
                    converted_field = from_json_obj(field,
                                                    t.__args__[0],
                                                    cast_decimal=cast_decimal)
                else:
                    converted_field = from_json_obj(json.loads(field),
                                                    t.__args__[0],
                                                    cast_decimal=cast_decimal)
                converted_dict[converted_field] = from_json_obj(
                    obj[field], t.__args__[1], cast_decimal=cast_decimal)
            # assert is_instance(converted_dict, t, cast_decimal=cast_decimal)
            return converted_dict
    raise AssertionError(_UNREACHABLE_ERROR_MSG)  # pragma: no cover