Description of problem:

Tab key does not work while listing the hammer sub-commands

How reproducible:

100%

Is this issue a regression from an earlier version:

Yes

Actual behavior:
After pressing the Tab key to list the hammer sub-commands, It does not prompt/lists sub-commands

Expected behavior:
After pressing the Tab key to list the hammer sub-commands, It should prompt/lists sub-commands

Business Impact / Additional info:

NA