Add more tests

Author: aisk

Lib/multiprocessing/shared_memory.py

@@ -37,6 +37,10 @@
 else:
     _SHM_NAME_PREFIX = 'wnsm_'
 
+if _USE_POSIX and hasattr(_posixshmem, "shm_rename"):
+    from _posixshmem import SHM_RENAME_EXCHANGE
+    from _posixshmem import SHM_RENAME_NOREPLACE
+
 
 def _make_filename():
     "Create a random filename for the shared memory object."
@@ -255,9 +259,6 @@ def unlink(self):
                 resource_tracker.unregister(self._name, "shared_memory")
 
     if _USE_POSIX and hasattr(_posixshmem, "shm_rename"):
-        from _posixshmem import SHM_RENAME_EXCHANGE
-        from _posixshmem import SHM_RENAME_NOREPLACE
-
         def rename(self, newname, flags=0):
             """Renames a shared memory block.
 

Lib/test/_test_multiprocessing.py

@@ -4376,7 +4376,7 @@ def test_shared_memory_recreate(self):
             self.addCleanup(shm2.unlink)
             self.assertEqual(shm2._name, names[1])
 
-    @unittest.skipUnless(hasattr(shared_memory, "rename"),
+    @unittest.skipUnless(hasattr(shared_memory.SharedMemory, "rename"),
                          "requires SharedMomery.rename")
     def test_shared_memory_rename(self):
         name1 = self._new_shm_name('testrename01_tsmb')
@@ -4387,6 +4387,30 @@ def test_shared_memory_rename(self):
         sms.rename(name2)
         self.assertEqual(sms.name, name2)
 
+    @unittest.skipUnless(hasattr(shared_memory.SharedMemory, "rename"),
+                         "requires SharedMomery.rename")
+    def test_shared_memory_rename_noreplace(self):
+        name1 = self._new_shm_name('testrename01_tsmb')
+        name2 = self._new_shm_name('testrename02_tsmb')
+        sms1 = shared_memory.SharedMemory(name1, create=True, size=512)
+        sms2 = shared_memory.SharedMemory(name2, create=True, size=512)
+        self.addCleanup(sms1.unlink)
+        self.addCleanup(sms2.unlink)
+
+        with self.assertRaises(FileExistsError):
+            sms1.rename(name2, flags=shared_memory.SHM_RENAME_NOREPLACE)
+
+    @unittest.skipUnless(hasattr(shared_memory.SharedMemory, "rename"),
+                         "requires SharedMomery.rename")
+    def test_shared_memory_rename_exchange(self):
+        name1 = self._new_shm_name('testrename01_tsmb')
+        name2 = self._new_shm_name('testrename02_tsmb')
+        sms1 = shared_memory.SharedMemory(name1, create=True, size=512)
+        sms2 = shared_memory.SharedMemory(name2, create=True, size=512)
+        self.addCleanup(sms2.unlink)
+
+        sms1.rename(name2, flags=shared_memory.SHM_RENAME_EXCHANGE)
+
     def test_invalid_shared_memory_creation(self):
         # Test creating a shared memory segment with negative size
         with self.assertRaises(ValueError):