Fix annotated refs when using future annotations for plain classes (#10)

Author: giograno

src/py_avro_schema/_schemas.py

@@ -1156,8 +1156,13 @@ def __init__(self, py_type: Type, namespace: Optional[str] = None, options: Opti
         super().__init__(py_type, namespace=namespace, options=options)
         py_type = _type_from_annotated(py_type)
 
+        # Try to get resolved type hints, but fall back to raw annotations if there are unresolved forward refs
+        try:
+            type_hints = get_type_hints(py_type, include_extras=True)
+        except NameError:
+            type_hints = py_type.__annotations__
         self.py_fields: list[tuple[str, type]] = []
-        for k, v in py_type.__annotations__.items():
+        for k, v in type_hints.items():
             self.py_fields.append((k, v))
         # We store __init__ parameters with default values. They can be used as defaults for the record.
         self.signature_fields = {

tests/models/__init__.py

@@ -0,0 +1,9 @@
+from __future__ import annotations
+
+Name = str
+
+
+class PyClass:
+    """For testing imports with future annotations"""
+
+    name: Name

tests/models/forward.py

@@ -143,3 +143,20 @@ class PyType:
 
     expected = {"fields": [{"name": "details", "type": "string"}], "name": "PyType", "type": "record"}
     assert_schema(PyType, expected)
+
+
+def test_type_aliases():
+    Name = str
+
+    class PyClass:
+        name: Name
+
+    expected = {"fields": [{"name": "name", "type": "string"}], "name": "PyClass", "type": "record"}
+    assert_schema(PyClass, expected)
+
+
+def test_type_aliases_future():
+    from tests.models.forward import PyClass
+
+    expected = {"fields": [{"name": "name", "type": "string"}], "name": "PyClass", "type": "record"}
+    assert_schema(PyClass, expected)