sphinxext: Warn if namespace or command pattern invalid

Calling the Sphinx extension with an invalid namespace or command
pattern currently results in a silent failure. Correct this oversight by
raising a warning, which will cause a build failure is
'warning-is-error' is enabled.

Change-Id: I63d18c86931d752c3a680e84a69df53bc04e7dfd
Signed-off-by: Stephen Finucane <sfinucan@redhat.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/cliff/sphinxext.py b/cliff/sphinxext.py
index d8468b6..5ec3448 100644
--- a/cliff/sphinxext.py
+++ b/cliff/sphinxext.py
@@ -268,6 +268,15 @@ class AutoprogramCliffDirective(rst.Directive):
                         if fnmatch.fnmatch(x, command_pattern)]
         else:
             commands = manager.commands.keys()
+
+        if not commands:
+            msg = 'No commands found in the "{}" namespace'
+            if command_pattern:
+                msg += ' using the "{}" command name/pattern'
+            msg += ('. Are you sure this is correct and the application being '
+                    'documented is installed?')
+            raise self.warning(msg.format(self.arguments[0], command_pattern))
+
         return dict((name, self._load_command(manager, name))
                     for name in commands)