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)
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)
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)
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)
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
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)
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)
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
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)
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]])
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])
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)
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)
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)
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