[mypyc] Fix is_native_ref_expr for class attrs.

Author: jhance

mypyc/irbuild/builder.py

@@ -979,17 +979,13 @@ def _analyze_iterable_item_type(self, expr: Expression) -> Type:
 
     def is_native_module(self, module: str) -> bool:
         """Is the given module one compiled by mypyc?"""
-        return module in self.mapper.group_map
+        return self.mapper.is_native_module(module)
 
     def is_native_ref_expr(self, expr: RefExpr) -> bool:
-        if expr.node is None:
-            return False
-        if "." in expr.node.fullname:
-            return self.is_native_module(expr.node.fullname.rpartition(".")[0])
-        return True
+        return self.mapper.is_native_ref_expr(expr)
 
     def is_native_module_ref_expr(self, expr: RefExpr) -> bool:
-        return self.is_native_ref_expr(expr) and expr.kind == GDEF
+        return self.mapper.is_native_module_ref_expr(expr)
 
     def is_synthetic_type(self, typ: TypeInfo) -> bool:
         """Is a type something other than just a class we've created?"""

mypyc/irbuild/mapper.py

@@ -217,7 +217,12 @@ def is_native_ref_expr(self, expr: RefExpr) -> bool:
         if expr.node is None:
             return False
         if "." in expr.node.fullname:
-            return self.is_native_module(expr.node.fullname.rpartition(".")[0])
+            cur = expr.node.fullname
+            while "." in cur:
+                cur = cur.rpartition(".")[0]
+                if self.is_native_module(cur):
+                    return True
+            return False
         return True
 
     def is_native_module_ref_expr(self, expr: RefExpr) -> bool:

mypyc/test-data/run-classes.test

@@ -2594,3 +2594,15 @@ def test_class_final_attribute_inherited() -> None:
     assert C().b == 2
     assert B().c == 3
     assert C().c == 3
+
+[case testClassWithFinalAttributeAccess]
+from typing import Final
+
+class C:
+    a: Final = {'x': 'y'}
+    b: Final = C.a
+
+def test_final_attribute() -> None:
+    assert C.a['x'] == 'y'
+    assert C.b['x'] == 'y'
+    assert C.a is C.b