DRIVERS-3130 Test wait queue timeout errors do not clear the pool (#1768)

Author: ShaneHarvey

source/client-side-operations-timeout/tests/waitQueueTimeout.json

@@ -0,0 +1,105 @@
+description: "WaitQueueTimeoutError does not clear the pool"
+
+schemaVersion: "1.9"
+
+runOnRequirements:
+  - minServerVersion: "4.4"
+    topologies: ["single", "replicaset", "sharded"]
+
+createEntities:
+  - client:
+      id: &failPointClient failPointClient
+      useMultipleMongoses: false
+  - client:
+      id: &client client
+      uriOptions:
+        maxPoolSize: 1
+        appname: &appname waitQueueTimeoutErrorTest
+      useMultipleMongoses: false
+      observeEvents:
+        - commandStartedEvent
+        - poolClearedEvent
+  - database:
+      id: &database database
+      client: *client
+      databaseName: &databaseName test
+
+tests:
+  - description: "WaitQueueTimeoutError does not clear the pool"
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *failPointClient
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+              failCommands: ["ping"]
+              blockConnection: true
+              blockTimeMS: 500
+              appName: *appname
+      # Start thread.
+      - name: createEntities
+        object: testRunner
+        arguments:
+          entities:
+            - thread:
+                id: &thread0 thread0
+      - name: runOnThread
+        object: testRunner
+        arguments:
+          thread: *thread0
+          operation:
+            name: runCommand
+            object: *database
+            arguments:
+              command: { ping: 1 }
+              commandName: ping
+      # Wait for the thread to checkout the only connection (maxPoolSize=1).
+      - name: waitForEvent
+        object: testRunner
+        arguments:
+          client: *client
+          event:
+            commandStartedEvent:
+              commandName: ping
+          count: 1
+      # Run another command with a short timeout to make it likely to get a WaitQueueTimeoutError.
+      - name: runCommand
+        object: *database
+        arguments:
+          timeoutMS: 100
+          command: { hello: 1 }
+          commandName: hello
+        expectError:
+          isTimeoutError: true
+      - name: waitForThread
+        object: testRunner
+        arguments:
+          thread: *thread0
+      # Run another command with no timeout to ensure the pool is not cleared.
+      - name: runCommand
+        object: *database
+        arguments:
+          command: { hello: 1 }
+          commandName: hello
+
+    expectEvents:
+      - client: *client
+        eventType: command
+        events:
+          - commandStartedEvent:
+              commandName: ping
+              databaseName: *databaseName
+              command:
+                ping: 1
+          - commandStartedEvent:
+              commandName: hello
+              databaseName: *databaseName
+              command:
+                hello: 1
+      # No poolClearedEvent.
+      - client: *client
+        eventType: cmap
+        events: []