Merge "Allow --help for specific commands"

cinderclient/shell.py

@@ -576,6 +576,12 @@ class OpenStackCinderShell(object):
                                                        do_help, args)
         self.parser = subcommand_parser
 
+        if argv and len(argv) > 1 and '--help' in argv:
+            argv = [x for x in argv if x != '--help']
+            if argv[0] in self.subcommands:
+                self.subcommands[argv[0]].print_help()
+                return 0
+
         if options.help or not argv:
             subcommand_parser.print_help()
             return 0

cinderclient/tests/unit/test_shell.py

@@ -16,6 +16,7 @@ import re
 import sys
 import unittest
 
+import ddt
 import fixtures
 import keystoneauth1.exceptions as ks_exc
 from keystoneauth1.exceptions import DiscoveryFailure
@@ -36,6 +37,7 @@ from cinderclient.tests.unit.fixture_data import keystone_client
 from cinderclient.tests.unit import utils
 
 
+@ddt.ddt
 class ShellTest(utils.TestCase):
 
     FAKE_ENV = {
@@ -132,6 +134,15 @@ class ShellTest(utils.TestCase):
             self.assertThat(help_text,
                             matchers.MatchesRegex(r, re.DOTALL | re.MULTILINE))
 
+    @ddt.data('backup-create --help', '--help backup-create')
+    def test_dash_dash_help_on_subcommand(self, cmd):
+        required = ['.*?^Creates a volume backup.']
+        help_text = self.shell(cmd)
+
+        for r in required:
+            self.assertThat(help_text,
+                            matchers.MatchesRegex(r, re.DOTALL | re.MULTILINE))
+
     def register_keystone_auth_fixture(self, mocker, url):
         mocker.register_uri('GET', url,
                             text=keystone_client.keystone_request_callback)