need empty list on windows

Author: minrk

ipyparallel/tests/test_ssh.py

@@ -29,15 +29,18 @@ def ssh_config(ssh_key, request):
     c.Cluster.controller_ip = '0.0.0.0'
     c.Cluster.engine_launcher_class = request.param
     engine_set_cfg = c[f"{request.param}EngineSetLauncher"]
+    engine_set_cfg.ssh_args = []
     if not windows:
-        engine_set_cfg.ssh_args = [
-            "-o",
-            "UserKnownHostsFile=/dev/null",
-            "-o",
-            "StrictHostKeyChecking=no",
-            "-i",
-            ssh_key,
-        ]
+        engine_set_cfg.ssh_args.extend(
+            [
+                "-o",
+                "UserKnownHostsFile=/dev/null",
+                "-o",
+                "StrictHostKeyChecking=no",
+                "-i",
+                ssh_key,
+            ]
+        )
     engine_set_cfg.scp_args = list(engine_set_cfg.ssh_args)  # copy
     if windows:
         engine_set_cfg.remote_python = "python"