I am using guard with minitest, and everything works great except growl notifications don't work.

Gemfile

gem 'growl'
gem 'guard'
gem 'guard-minitest'
gem 'json'
gem 'minitest'
gem 'rack-test'
gem 'ruby_gntp'
gem 'sinatra'

Guardfile

guard :minitest do
  watch(%r{^spec/(.*)_spec\.rb$})
  watch(%r{^spec/test_helper.rb$})
  watch('beacons_app.rb') { "spec/beacons_app_spec.rb" }
end

notification :gntp

(NOTE: I have tried putting the "notification" line at the top of the file as well)

If I run bundle exec guard notifiers gntp shows as available:

  +-------------------+-----------+------+--------+-------------+
  | Name              | Available | Used | Option | Value       |
  +-------------------+-----------+------+--------+-------------+
  | gntp              | ✔         | ✔    | title  | "Notiffany" |
  |                   |           |      | sticky | false       |
  +-------------------+-----------+------+--------+-------------+
  | growl             | ✘         | ✘    |        |             |
  +-------------------+-----------+------+--------+-------------+
  | terminal_notifier | ✘         | ✘    |        |             |
  +-------------------+-----------+------+--------+-------------+
  | libnotify         | ✘         | ✘    |        |             |
  +-------------------+-----------+------+--------+-------------+
  | notifysend        | ✘         | ✘    |        |             |
  +-------------------+-----------+------+--------+-------------+
  | notifu            | ✘         | ✘    |        |             |
  +-------------------+-----------+------+--------+-------------+
  | emacs             | ✘         | ✘    |        |             |
  +-------------------+-----------+------+--------+-------------+
  | tmux              | ✘         | ✘    |        |             |
  +-------------------+-----------+------+--------+-------------+
  | terminal_title    | ✔         | ✔    | title  | "Notiffany" |
  +-------------------+-----------+------+--------+-------------+
  | file              | ✘         | ✘    |        |             |
  +-------------------+-----------+------+--------+-------------+

Growl is running and working (I can send to it successfully using growlnotify at the command line).

And when I run bundle exec guard, my tests run fine, and file changes trigger the tests to rerun in the terminal, as expected. But no growl notifications.

How can I make them work?

UPDATE

This was caused by a bug in guard-minitest, and it has now been fixed: https://github.com/guard/guard-minitest/commit/35ba44c2df7d25b8c3631be2571d3f1411e64185

hmmm, my first guess would be that guard is not enabled in your growl settings:

have you checked your growl preferences?

I would also check http://www.rubydoc.info/github/guard/guard/Guard/Notifier/Growl to ensure you have correct config options. if that doesn't work, open an issue at https://github.com/guard/guard-minitest/issues

Update: looks like this was a bug in guard-minitest https://github.com/guard/guard-minitest/issues/126