Method not available on this version
This method is only available on newer versions.
The first available version (v2_6_3) is shown here.
banner()
protected
The banner for this
class. You can customize it if you are invoking the thor class by another
ways which is not the Bundler::Thor::Runner.
# File lib/bundler/vendor/thor/lib/thor/group.rb, line 238
def banner
"#{basename} #{self_command.formatted_usage(self, false)}"
end