When running the attached test, the class defined like this is not deserialising correctly.
@dataclass_json
@dataclass
class E:
a: list["A"]
The a member is left as a dict instead of getting turned into class A.
I spotted this note in the python docs:
Note
PEP 585 generic types such as list["SomeClass"] will not be implicitly transformed into list[ForwardRef("SomeClass")] and thus will not automatically resolve to list[SomeClass].
Indeed, adding ForwardRef does make it work again, so this might just be a limitation of python. Actually while looking into this, I found that this is already fixed in python 3.11: https://github.com/python/cpython/commit/b465b606049f6f7dd0711cb031fdaa251818741a. I'll create this issue anyway for anyone else that might encounter the same issue in earlier python releases.
Full test code below:
```
from dataclasses import dataclass
from dataclasses_json import dataclass_json
from typing import ForwardRef
@dataclass_json
@dataclass(frozen=True)
class A:
value: int
@dataclass_json
@dataclass
class B:
a: A
@dataclass_json
@dataclass
class C:
a: "A"
@dataclass_json
@dataclass
class D:
a: list[A]
@dataclass_json
@dataclass
class E:
a: list["A"]
@dataclass_json
@dataclass
class F:
a: list[ForwardRef("A")]
if __name__ == "__main__":
import unittest
class Test(unittest.TestCase):
def test_b(self) -> None:
uut = B(A(0))
json = uut.to_json()
parsed = B.from_json(json)
self.assertEqual(type(parsed.a), A)
def test_c(self) -> None:
uut = C(A(0))
json = uut.to_json()
parsed = C.from_json(json)
self.assertEqual(type(parsed.a), A)
def test_d(self) -> None:
uut = D([A(0)])
json = uut.to_json()
parsed = D.from_json(json)
self.assertEqual(type(parsed.a[0]), A)
def test_e(self) -> None:
uut = E([A(0)])
json = uut.to_json()
parsed = E.from_json(json)
self.assertEqual(type(parsed.a[0]), A)
def test_F(self) -> None:
uut = F([A(0)])
json = uut.to_json()
parsed = F.from_json(json)
self.assertEqual(type(parsed.a[0]), A)
unittest.main()
```
When running the attached test, the class defined like this is not deserialising correctly.
The
amember is left as a dict instead of getting turned into classA.I spotted this note in the python docs:
Indeed, adding
ForwardRefdoes make it work again, so this might just be a limitation of python. Actually while looking into this, I found that this is already fixed in python 3.11: https://github.com/python/cpython/commit/b465b606049f6f7dd0711cb031fdaa251818741a. I'll create this issue anyway for anyone else that might encounter the same issue in earlier python releases.Full test code below: