gh-136285: Improve pickle protocol testing in test_interpreters

Lib/concurrent/interpreters/__init__.py

@@ -146,12 +146,8 @@ def __del__(self):
         self._decref()
 
     # for pickling:
-    def __getnewargs__(self):
-        return (self._id,)
-
-    # for pickling:
-    def __getstate__(self):
-        return None
+    def __reduce__(self):
+        return (type(self), (self._id,))
 
     def _decref(self):
         if not self._ownsref:

Lib/concurrent/interpreters/_queues.py

@@ -129,12 +129,8 @@ def __hash__(self):
         return hash(self._id)
 
     # for pickling:
-    def __getnewargs__(self):
-        return (self._id,)
-
-    # for pickling:
-    def __getstate__(self):
-        return None
+    def __reduce__(self):
+        return (type(self), (self._id,))
 
     def _set_unbound(self, op, items=None):
         assert not hasattr(self, '_unbound')

Lib/test/support/channels.py

@@ -105,12 +105,8 @@ def __eq__(self, other):
         return other._id == self._id
 
     # for pickling:
-    def __getnewargs__(self):
-        return (int(self._id),)
-
-    # for pickling:
-    def __getstate__(self):
-        return None
+    def __reduce__(self):
+        return (type(self), (int(self._id),))
 
     @property
     def id(self):

Lib/test/test_interpreters/test_api.py

@@ -412,7 +412,7 @@ def test_equality(self):
 
     def test_pickle(self):
         interp = interpreters.create()
-        for protocol in range(2, pickle.HIGHEST_PROTOCOL + 1):
+        for protocol in range(pickle.HIGHEST_PROTOCOL + 1):
             with self.subTest(protocol=protocol):
                 data = pickle.dumps(interp, protocol)
                 unpickled = pickle.loads(data)

Lib/test/test_interpreters/test_channels.py

@@ -120,12 +120,13 @@ def test_equality(self):
         self.assertNotEqual(ch1, ch2)
 
     def test_pickle(self):
-        ch, _ = channels.create()
-        for protocol in range(2, pickle.HIGHEST_PROTOCOL + 1):
-            with self.subTest(protocol=protocol):
-                data = pickle.dumps(ch, protocol)
-                unpickled = pickle.loads(data)
-                self.assertEqual(unpickled, ch)
+        recv, send = channels.create()
+        for ch in [recv, send]:
+            for protocol in range(pickle.HIGHEST_PROTOCOL + 1):
+                with self.subTest(ch=ch, protocol=protocol):
+                    data = pickle.dumps(ch, protocol)
+                    unpickled = pickle.loads(data)
+                    self.assertEqual(unpickled, ch)
 
 
 class TestSendChannelAttrs(TestBase):
@@ -154,7 +155,7 @@ def test_equality(self):
 
     def test_pickle(self):
         _, ch = channels.create()
-        for protocol in range(2, pickle.HIGHEST_PROTOCOL + 1):
+        for protocol in range(pickle.HIGHEST_PROTOCOL + 1):
             with self.subTest(protocol=protocol):
                 data = pickle.dumps(ch, protocol)
                 unpickled = pickle.loads(data)

Lib/test/test_interpreters/test_queues.py

@@ -188,7 +188,7 @@ def test_equality(self):
 
     def test_pickle(self):
         queue = queues.create()
-        for protocol in range(2, pickle.HIGHEST_PROTOCOL + 1):
+        for protocol in range(pickle.HIGHEST_PROTOCOL + 1):
             with self.subTest(protocol=protocol):
                 data = pickle.dumps(queue, protocol)
                 unpickled = pickle.loads(data)