Rails test_helper with jnunemaker's matchy and a few handy custom matchers

test_helper.rb

ENV["RAILS_ENV"] = "test"
require File.expand_path(File.dirname(__FILE__) + "/../config/environment")
require 'test_help'

gem 'jnunemaker-matchy', '>= 0.4.0'
require 'matchy'

class ActiveSupport::TestCase  
  self.use_transactional_fixtures = true
  self.use_instantiated_fixtures  = false
  
  fixtures :all
  
  custom_matcher :be_nil do |receiver, matcher, args|
    matcher.positive_failure_message = "Expected #{receiver} to be nil but it wasn't"
    matcher.negative_failure_message = "Expected #{receiver} not to be nil but it was"
    receiver.nil?
  end
  
  custom_matcher :be_valid do |receiver, matcher, args|
    matcher.positive_failure_message = "Expected to be valid but it was invalid #{receiver.errors.inspect}"
    matcher.negative_failure_message = "Expected to be invalid but it was valid #{receiver.errors.inspect}"
    receiver.valid?
  end
  
  custom_matcher :have_error_on do |receiver, matcher, args|
    receiver.valid?
    
    attribute = args[0]
    expected_message = args[1]
    
    if expected_message.nil?
      matcher.positive_failure_message = "#{receiver} had no errors on #{attribute}"
      matcher.negative_failure_message = "#{receiver} had errors on #{attribute} #{receiver.errors.inspect}"
      !receiver.errors.on(attribute).blank?
    else
      actual = receiver.errors.on(attribute)
      matcher.positive_failure_message = %Q(Expected error on #{attribute} to be "#{expected_message}" but was "#{actual}")
      matcher.negative_failure_message = %Q(Expected error on #{attribute} not to be "#{expected_message}" but was "#{actual}")
      actual == expected_message
    end
  end
end