Remove shell module specialcases

Shell is implemented via the command module.  There was a special case
in mod_args to do that.  Make shell into an action plugin to handle that
instead.

Also move the special case for the command nanny into a command module
action plugin.  This is more appropriate as we then do not have to send
a parameter that is only for the command module to every single module.

lib/ansible/module_utils/basic.py

@@ -812,12 +812,11 @@ class AnsibleModule(object):
         self._warnings = []
         self._deprecations = []
         self._clean = {}
-        self._command_warn = True
 
         self.aliases = {}
         self._legal_inputs = ['_ansible_check_mode', '_ansible_no_log', '_ansible_debug', '_ansible_diff', '_ansible_verbosity',
                               '_ansible_selinux_special_fs', '_ansible_module_name', '_ansible_version', '_ansible_syslog_facility',
-                              '_ansible_socket', '_ansible_shell_executable', '_ansible_command_warnings']
+                              '_ansible_socket', '_ansible_shell_executable']
         self._options_context = list()
 
         if add_file_common_args:
@@ -1630,9 +1629,6 @@ class AnsibleModule(object):
             elif k == '_ansible_shell_executable' and v:
                 self._shell = v
 
-            elif k == '_ansible_command_warnings' and v:
-                self._command_warn = v
-
             elif check_invalid_arguments and k not in legal_inputs:
                 unsupported_parameters.add(k)
 

lib/ansible/modules/commands/command.py

@@ -165,7 +165,8 @@ def main():
             executable=dict(),
             creates=dict(type='path'),
             removes=dict(type='path'),
-            warn=dict(type='bool'),
+            # The default for this really comes from the action plugin
+            warn=dict(type='bool', default=True),
             stdin=dict(required=False),
         )
     )
@@ -179,9 +180,6 @@ def main():
     warn = module.params['warn']
     stdin = module.params['stdin']
 
-    if warn is None:
-        warn = module._command_warn
-
     if not shell and executable:
         module.warn("As of Ansible 2.4, the parameter 'executable' is no longer supported with the 'command' module. Not using '%s'." % executable)
         executable = None

lib/ansible/parsing/mod_args.py

@@ -116,21 +116,6 @@ class ModuleArgsParser:
         else:
             return (tokens[0], "")
 
-    def _handle_shell_weirdness(self, action, args):
-        '''
-        given an action name and an args dictionary, return the
-        proper action name and args dictionary.  This mostly is due
-        to shell/command being treated special and nothing else
-        '''
-
-        # the shell module really is the command module with an additional
-        # parameter
-        if action == 'shell':
-            action = 'command'
-            args['_uses_shell'] = True
-
-        return (action, args)
-
     def _normalize_parameters(self, thing, action=None, additional_args=None):
         '''
         arguments can be fuzzy.  Deal with all the forms.
@@ -319,7 +304,4 @@ class ModuleArgsParser:
                                                                                                                                   ", ".join(RAW_PARAM_MODULES)),
                                          obj=self._task_ds)
 
-        # shell modules require special handling
-        (action, args) = self._handle_shell_weirdness(action, args)
-
         return (action, args, delegate_to)

lib/ansible/plugins/action/__init__.py

@@ -612,9 +612,6 @@ class ActionBase(with_metaclass(ABCMeta, object)):
         # make sure all commands use the designated shell executable
         module_args['_ansible_shell_executable'] = self._play_context.executable
 
-        # let command know it should avoid specific warnings
-        module_args['_ansible_command_warnings'] = C.COMMAND_WARNINGS
-
     def _update_connection_options(self, options, variables=None):
         ''' ensures connections have the appropriate information '''
         update = {}

lib/ansible/plugins/action/command.py

@@ -0,0 +1,25 @@
+# Copyright: (c) 2017, Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+from ansible import constants as C
+from ansible.plugins.action import ActionBase
+from ansible.utils.vars import merge_hash
+
+
+class ActionModule(ActionBase):
+
+    def run(self, tmp=None, task_vars=None):
+        self._supports_async = True
+        results = super(ActionModule, self).run(tmp, task_vars)
+
+        # Command module has a special config option to turn off the command nanny warnings
+        if 'warn' not in self._task.args:
+            self._task.args['warn'] = C.COMMAND_WARNINGS
+
+        wrap_async = self._task.async_val and not self._connection.has_native_async
+        results = merge_hash(results, self._execute_module(tmp=tmp, task_vars=task_vars, wrap_async=wrap_async))
+
+        return results

lib/ansible/plugins/action/shell.py

@@ -0,0 +1,25 @@
+# Copyright: (c) 2017, Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+from ansible.plugins.action import ActionBase
+from ansible.utils.vars import merge_hash
+
+
+class ActionModule(ActionBase):
+
+    def run(self, tmp=None, task_vars=None):
+        # Shell module is implemented via command
+        self._task.action = 'command'
+        self._task.args['_uses_shell'] = True
+
+        command_action = self._shared_loader_obj.action_loader.get('command',
+                                                                   task=self._task,
+                                                                   connection=self._connection,
+                                                                   play_context=self._play_context,
+                                                                   loader=self._loader,
+                                                                   templar=self._templar,
+                                                                   shared_loader_obj=self._shared_loader_obj)
+        return command_action.run(task_vars=task_vars)