module Pact::JsonWarning

def check_for_active_support_json
  @already_warned ||= false
  # Active support clobbers the as_json methods defined in the json/add directory of the json gem.
  # These methods are required to serialize and deserialize the Regexp and Symbol classes properly.
  # You can potentially fix this by making sure the json gem is required AFTER the active_support/json gem
  # OR if you don't use the json part of activesupport you could only require the parts of active support you really need
  # OR you can only use strings in your pacts.
  # Good luck.
  # If someone knows how to make sure the pact gem uses the json gem as_json methods when activesupport/json is used in the calling code,
  # without breaking the calling code, which may depend on activesupport/json... then please fix this.
  # Note: we can probably do this in Ruby 2.0 with refinements, but for now, we're all stuck on 1.9 :(
  unless @already_warned
    unless Regexp.new('').as_json.is_a?(Hash)
      Logger.new($stderr).warn("It appears you are using ActiveSupport json in your project. You are now in rubygems hell. Please see Pact::JsonWarning for more info.")
      @already_warned = true
    end
  end
end