add ssh_extra_args option

Author: dalvizu

doc/source/backends.rst

@@ -66,7 +66,7 @@ This is a pure SSH backend using the ``ssh`` command. Example::
     $ py.test --ssh-config=/path/to/ssh_config --hosts='ssh://server'
     $ py.test --ssh-identity-file=/path/to/key --hosts='ssh://server'
     $ py.test --hosts='ssh://server?timeout=60&controlpersist=120'
-
+    $ py.test --hosts='ssh://server' --ssh-extra-args='-o StrictHostKeyChecking=no'
 
 By default timeout is set to 10 seconds and ControlPersist is set to 60 seconds.
 You can disable persistent connection by passing `controlpersist=0` to the options.

testinfra/plugin.py

@@ -59,6 +59,12 @@ def pytest_addoption(parser):
         dest="ssh_config",
         help="SSH config file",
     )
+    group.addoption(
+        "--ssh-extra-args",
+        action="store",
+        dest="ssh_extra_args",
+        help="SSH extra args",
+    )
     group.addoption(
         "--ssh-identity-file",
         action="store",