Oops, make the test only run on Python 3.9+

tests/test_core.py

@@ -1,28 +1,33 @@
 from dataclasses import dataclass
 import pytest
-from typing import Optional, Set
+from typing import Optional, Set, List
 
 from dataclasses_json import dataclass_json
+import sys
 
 
-@dataclass_json
-@dataclass
-class Config:
- options: list["Option"]
+# This test exists *only* to demonstrate a bug on Python 3.9+
+# It uses syntax that is not valid on earlier versions of Python!
+if sys.version_info >= (3, 9):
+ @dataclass_json
+ @dataclass
+ class Config:
+ options: list["Option"]
 
-@dataclass_json
-@dataclass
-class Option:
- label: str
+ @dataclass_json
+ @dataclass
+ class Option:
+  label: str
 
-@dataclass_json
-@dataclass
-class ConfigWithoutStringOptions:
- options: list[Option]
+ @dataclass_json
+ @dataclass
+ class ConfigWithoutStringOptions:
+  options: list[Option]
 
 
 
 
+@pytest.mark.skipif(sys.version_info < (3, 9), reason="requires generic types for bug")
 class TestWarning:
  def test_warns_about_nondeterministic_resolution(self):
  with pytest.warns(UserWarning, match="Assuming hint Option resolves to .*"):