oamg · pirat89 · Aug 23, 2022 · Jul 22, 2022 · Aug 22, 2022
diff --git a/leapp/cli/__init__.py b/leapp/cli/__init__.py
@@ -1,11 +1,12 @@
-
 import os
 import pkgutil
 import socket
 import sys
+import textwrap
 
 from leapp import VERSION
 from leapp.cli import commands
+from leapp.exceptions import UnknownCommandError
 from leapp.utils.clicmd import command
 
 
@@ -40,4 +41,16 @@ def main():
 
     os.environ['LEAPP_HOSTNAME'] = socket.getfqdn()
     _load_commands(cli.command)
-    cli.command.execute('leapp version {}'.format(VERSION))
+    try:
+        cli.command.execute('leapp version {}'.format(VERSION))
+    except UnknownCommandError as e:
+        bad_cmd = (
+            "Command \"{CMD}\" is unknown.\nMost likely there is a typo in the command or particular "
+            "leapp repositories that provide this command are not present on the system.\n"
+            "You can try to install the missing content e.g. by the following
8000
 command: "
+            "`dnf install 'leapp-command({CMD})'`")
+        if e.requested.startswith('-'):
+            # A quick ack not to confuse users with install a leapp-command(--some-wrong-argument) suggestion
+            bad_cmd = "No such argument {CMD}"
+        print(bad_cmd.format(CMD=e.requested))
+        sys.exit(1)
diff --git a/leapp/exceptions.py b/leapp/exceptions.py
@@ -102,6 +102,12 @@ class CommandDefinitionError(LeappError):
     pass
 
 
+class UnknownCommandError(LeappError):
+    def __init__(self, command):
+        super().__init__('Unknown command: {}'.format(command))
+        self.requested = command
+
+
 class LeappRuntimeError(LeappError):
     pass
 

diff --git a/leapp/utils/clicmd.py b/leapp/utils/clicmd.py
@@ -1,12 +1,12 @@
 import functools
 import os
 import sys
-
-from argparse import ArgumentParser, _SubParsersAction, RawDescriptionHelpFormatter
+from argparse import (ArgumentParser, RawDescriptionHelpFormatter,
+                      _SubParsersAction)
 
 import six
-
-from leapp.exceptions import CommandDefinitionError, UsageError, CommandError
+from leapp.exceptions import (CommandDefinitionError, CommandError,
+                              UnknownCommandError, UsageError)
 
 
 class _LeappArgumentParser(ArgumentParser):
@@ -23,6 +23,7 @@ class _LeappHelpFormatter(RawDescriptionHelpFormatter):
     """
     Capitalizes section headings in the help output
     """
+
     def start_section(self, heading):
         return super(_LeappHelpFormatter, self).start_section(heading.capitalize())
 
@@ -38,6 +39,7 @@ class _SubParserActionOverride(_SubParsersAction):
 
     The additional code will not be executed if python 2.7.9 or higher is found.
     """
+
     def __call__(self, parser, namespace, values, option_string=None):
         super(_SubParserActionOverride, self).__call__(parser, namespace, values, option_string)
         if sys.version_info >= (2, 7, 9):
@@ -54,6 +56,7 @@ class Command(object):
     """
     Command implements a convenient command-based argument parsing the framework.
     """
+
     def __init__(self, name, target=None, help='', description=None):  # noqa; pylint: disable=redefined-builtin
         """
         :param name: Name of the sub command
@@ -100,8 +103,10 @@ def execute(self, version):
         args, leftover = parser.parse_known_args()
         if leftover:
             cmdname = args.prog.split()[-1]
-            # NOTE(ivasilev) No vetting of cmdname is necessary here as unless a proper leapp subcommand was
-            # invocated parser.parse_known_args() would have thrown an exception
+            if cmdname not in self._sub_commands:
+                cmdname = leftover[0]
+            if cmdname not in self._sub_commands:
+                raise UnknownCommandError(cmdname)
             self._sub_commands[cmdname].parser.error(leftover)
         args.func(args)