Move test to test_types.py

Author: ByteFlowing1337

Lib/test/test_free_threading/test_genericalias.py

@@ -1,9 +1,12 @@
 import unittest
+import threading
 from typing import TypeVar
 from test.support import threading_helper
 
 threading_helper.requires_working_threading(module=True)
 
+NTHREADS = 10
+
 
 class TestGenericAlias(unittest.TestCase):
     def test_parameters_race(self):
@@ -28,6 +31,24 @@ def refresh():
             *[refresh for _ in range(2)],
         ])
 
+    def test_shared_generic_alias_iter(self):
+        # See https://github.com/python/cpython/issues/154043
+        def worker(it, barrier):
+            barrier.wait()
+            try:
+                next(it)
+            except StopIteration:
+                pass
+                bar = threading.Barrier(NTHREADS)
+
+        bar = threading.Barrier(NTHREADS)
+        number_of_iterations = 50
+        for _ in range(number_of_iterations):
+            shared = iter(list[int])
+            threading_helper.run_concurrently(
+                worker_func=worker, nthreads=NTHREADS, args=(shared, bar)
+            )
+
 
 if __name__ == "__main__":
     unittest.main()