make sure subcommand help prints more useful help message..

ui/medashare/cli.py

@@ -1421,6 +1421,9 @@ def main():
 	subparsers = parser.add_subparsers(title='subcommands',
 	    description='valid subcommands', help='additional help')
 
+	parser_help = subparsers.add_parser('help', help='get help')
+	parser_help.set_defaults(func=lambda *args: (parser.print_help(), sys.exit(0)))
+
 	parser_gi = subparsers.add_parser('genident', help='generate identity')
 	parser_gi.add_argument('tagvalue', nargs='+',
 	    help='add the arg as metadata for the identity, tag=[value]')
@@ -2259,6 +2262,31 @@ class _TestCases(unittest.TestCase):
 			self.assertEqual(s, str(pathpref / '.medashare_store.sqlite3'))
 			self.assertEqual(c, str(pathpref / '.medashare_cache.pasn1'))
 
+	def test_help(self):
+		# that subcommand help is the same as --help
+
+		with mock.patch('sys.stdout', io.StringIO()) as stdout, \
+		    mock.patch('sys.argv', [ 'progname', '--help', ]) as argv:
+			with self.assertRaises(SystemExit) as cm:
+				main()
+
+				# XXX - Minor hack till other tests fixed
+				sys.exit(0)
+
+			dashhelp = stdout.getvalue()
+
+		with mock.patch('sys.stdout', io.StringIO()) as stdout, \
+		    mock.patch('sys.argv', [ 'progname', 'help', ]) as argv:
+			with self.assertRaises(SystemExit) as cm:
+				main()
+
+				# XXX - Minor hack till other tests fixed
+				sys.exit(0)
+
+			subhelp = stdout.getvalue()
+
+		self.assertEqual(dashhelp, subhelp)
+
 	#@unittest.skip('temp')
 	def test_cmds(self):
 		cmds = sorted(self.fixtures.glob('cmd.*.json'))