Merge pull request #5 from seandstewart/seandstewart/type-alias-type-origin

fix: extract the real `__value__` from a `TypeAliasType` when calling `origin(...)`

Author: seandstewart

src/typelib/py/inspection.py

@@ -115,6 +115,9 @@ def origin(annotation: tp.Any) -> tp.Any:
         a = args(actual)
         actual = a[0] if a else actual
 
+    if istypealiastype(actual):
+        actual = actual.__value__
+
     actual = tp.get_origin(actual) or actual
 
     # provide defaults for generics

tests/unit/py/test_inspection.py

@@ -17,6 +17,7 @@
 import types
 import typing
 import typing as t
+import typing_extensions as te
 import uuid
 from unittest import mock
 
@@ -45,6 +46,7 @@ class MyClass: ...
     user_type=dict(annotation=MyClass, expected=MyClass),
     class_var_subscripted=dict(annotation=t.ClassVar[str], expected=str),
     class_var_unsubsripted=dict(annotation=t.ClassVar, expected=t.ClassVar),
+    type_alias_type=dict(annotation=te.TypeAliasType("T", dict), expected=dict),
 )
 def test_origin(annotation, expected):
     # When