How to silence `Shell` (ruby stdlib) `notify` feature?

Question

require 'shell'
sh = Shell.new
sh.verbose = false
sh.debug = false
print sh.system('date')

Expected output

Wed Nov 10 13:08:09 EST 2021

Observed output

shell(#<Th:0x00007fd016064058 run>): /bin/date
Wed Nov 10 13:08:09 EST 2021

The unwanted line comes from Shell::CommandProcessor#notify

Answer 1

After some investigation there seems to be a confusing design flaw (or feature?) in Shell . Initally it seems you should be able to mutate verbose and debug on an instance of Shell , but it turns out the root notify method itself lives in the class , not the instance.

Hence instance level settings will only have limited effect, as the class method Shell.notify will be unaware of instance settings.

Solution - use class-level settings instead:

Shell.verbose = false
Shell.debug   = false

Output will now be only:

Wed Nov 10 13:08:09 EST 2021