fix ssh cli defaults (#75245) (#76347)

* fix ssh cli defaults

  fixes #75221

(cherry picked from commit e5a2fe4c41)

Co-authored-by: Brian Coca <bcoca@users.noreply.github.com>

changelogs/fragments/fix_cli_ssh_defaults.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - cli defaults for ssh args set to None as '' was bypassing normal default.

lib/ansible/cli/arguments/option_helpers.py

@@ -253,13 +253,13 @@ def add_connect_options(parser):
                                help="connection type to use (default=%s)" % C.DEFAULT_TRANSPORT)
     connect_group.add_argument('-T', '--timeout', default=C.DEFAULT_TIMEOUT, type=int, dest='timeout',
                                help="override the connection timeout in seconds (default=%s)" % C.DEFAULT_TIMEOUT)
-    connect_group.add_argument('--ssh-common-args', default='', dest='ssh_common_args',
+    connect_group.add_argument('--ssh-common-args', default=None, dest='ssh_common_args',
                                help="specify common arguments to pass to sftp/scp/ssh (e.g. ProxyCommand)")
-    connect_group.add_argument('--sftp-extra-args', default='', dest='sftp_extra_args',
+    connect_group.add_argument('--sftp-extra-args', default=None, dest='sftp_extra_args',
                                help="specify extra arguments to pass to sftp only (e.g. -f, -l)")
-    connect_group.add_argument('--scp-extra-args', default='', dest='scp_extra_args',
+    connect_group.add_argument('--scp-extra-args', default=None, dest='scp_extra_args',
                                help="specify extra arguments to pass to scp only (e.g. -l)")
-    connect_group.add_argument('--ssh-extra-args', default='', dest='ssh_extra_args',
+    connect_group.add_argument('--ssh-extra-args', default=None, dest='ssh_extra_args',
                                help="specify extra arguments to pass to ssh only (e.g. -R)")
 
     parser.add_argument_group(connect_group)

lib/ansible/plugins/connection/ssh.py

@@ -83,6 +83,7 @@ DOCUMENTATION = '''
                 version_added: '2.7'
           vars:
               - name: ansible_ssh_common_args
+          default: ''
       ssh_executable:
           default: ssh
           description:
@@ -130,6 +131,7 @@ DOCUMENTATION = '''
             - key: scp_extra_args
               section: ssh_connection
               version_added: '2.7'
+          default: ''
       sftp_extra_args:
           description: Extra exclusive to the ``sftp`` CLI
           vars:
@@ -141,6 +143,7 @@ DOCUMENTATION = '''
             - key: sftp_extra_args
               section: ssh_connection
               version_added: '2.7'
+          default: ''
       ssh_extra_args:
           description: Extra exclusive to the 'ssh' CLI
           vars:
@@ -152,6 +155,7 @@ DOCUMENTATION = '''
             - key: ssh_extra_args
               section: ssh_connection
               version_added: '2.7'
+          default: ''
       retries:
           # constant: ANSIBLE_SSH_RETRIES
           description: Number of attempts to connect.