def test_isinstance(self):
@dataclass
class ExampleDataclass:
int_field: int
T = TypeVar("T")
positive_test_cases = [
(1, int),
("Hello, world", str),
({
"key": "Value"
}, dict),
({
"key": "Value"
}, Dict),
({
"key": "Value"
}, Dict[str, str]),
({
"key": 1
}, Dict[str, int]),
({
1: 2
}, Dict[T, T][int]),
(ExampleDataclass(1), ExampleDataclass),
(ExampleDataclass(1), dataclass),
]
for obj, type_ in positive_test_cases:
with self.subTest(obj=obj, type_=type_):
self.assertTrue(isinstance(obj, type_))
negative_test_cases = [
(1, str),
("Hello, world", int),
({
"key": "Value"
}, Dict[str, int]),
({
"key": "Value"
}, Dict[int, str]),
({
"key": 1
}, Dict[str, str]),
({
1: 2
}, Dict[T, T][str]),
(ExampleDataclass, dataclass),
(ExampleDataclass, ExampleDataclass),
]
for obj, type_ in negative_test_cases:
with self.subTest(obj=obj, type_=type_):
self.assertFalse(isinstance(obj, type_))
def bson_int_deserializer(cls, obj):
"""
Mongo implicitly converts ints to floats
Attempt to coerce back
Fail if coercion lossy
"""
if isinstance(obj, cls):
return obj
try:
coerced_obj = cls(obj)
except:
coerced_obj = None
if coerced_obj == obj:
return coerced_obj
raise DeserializationError("Cannot deserialize {} {!r} to type {}".format(
type(obj).__name__, obj, cls.__name__))