PYTHON-3160 Fix MMAPv1 tests (#914)

Author: ShaneHarvey

test/sessions/driver-sessions-dirty-session-errors.json

@@ -448,7 +448,6 @@
           "name": "insertOne",
           "object": "collection0",
           "arguments": {
-            "session": "session0",
             "document": {
               "_id": 2
             }

test/test_session.py

@@ -183,12 +183,11 @@ def test_implicit_sessions_checkout(self):
         # "To confirm that implicit sessions only allocate their server session after a
         # successful connection checkout" test from Driver Sessions Spec.
         succeeded = False
+        lsid_set = set()
         failures = 0
         for _ in range(5):
             listener = EventListener()
-            client = rs_or_single_client(
-                event_listeners=[listener], maxPoolSize=1, retryWrites=True
-            )
+            client = rs_or_single_client(event_listeners=[listener], maxPoolSize=1)
             cursor = client.db.test.find({})
             ops: List[Tuple[Callable, List[Any]]] = [
                 (client.db.test.find_one, [{"_id": 1}]),
@@ -225,16 +224,15 @@ def thread_target(op, *args):
                 thread.join()
                 self.assertIsNone(thread.exc)
             client.close()
-            lsid_set = set()
+            lsid_set.clear()
             for i in listener.results["started"]:
                 if i.command.get("lsid"):
                     lsid_set.add(i.command.get("lsid")["id"])
             if len(lsid_set) == 1:
                 succeeded = True
             else:
                 failures += 1
-        print(failures)
-        self.assertTrue(succeeded)
+        self.assertTrue(succeeded, lsid_set)
 
     def test_pool_lifo(self):
         # "Pool is LIFO" test from Driver Sessions Spec.

test/unified_format.py

@@ -766,11 +766,30 @@ def setUp(self):
     def maybe_skip_test(self, spec):
         # add any special-casing for skipping tests here
         if client_context.storage_engine == "mmapv1":
-            if "Dirty explicit session is discarded" in spec["description"]:
+            if (
+                "Dirty explicit session is discarded" in spec["description"]
+                or "Dirty implicit session is discarded" in spec["description"]
+            ):
                 raise unittest.SkipTest("MMAPv1 does not support retryWrites=True")
         elif "Client side error in command starting transaction" in spec["description"]:
             raise unittest.SkipTest("Implement PYTHON-1894")
 
+        # Some tests need to be skipped based on the operations they try to run.
+        for op in spec["operations"]:
+            name = op["name"]
+            if name == "count":
+                self.skipTest("PyMongo does not support count()")
+            if name == "listIndexNames":
+                self.skipTest("PyMongo does not support list_index_names()")
+            if client_context.storage_engine == "mmapv1":
+                if name == "createChangeStream":
+                    self.skipTest("MMAPv1 does not support change streams")
+                if name == "withTransaction" or name == "startTransaction":
+                    self.skipTest("MMAPv1 does not support document-level locking")
+            if not client_context.test_commands_enabled:
+                if name == "failPoint" or name == "targetedFailPoint":
+                    self.skipTest("Test commands must be enabled to use fail points")
+
     def process_error(self, exception, spec):
         is_error = spec.get("isError")
         is_client_error = spec.get("isClientError")