Monkey patch subscriber to test that only one subscriber per method is added.

Methods
C
O
Class Public methods
clear()

Source: show | on GitHub 

# File activesupport/test/subscriber_test.rb, line 9
def self.clear
  @@events = []
end
Instance Public methods
open_party(event)

Source: show | on GitHub 

# File activesupport/test/subscriber_test.rb, line 13
def open_party(event)
  events << event
end