vendor/plugins/rspec/rspec/examples/pure/custom_expectation_matchers.rb

   1 module AnimalSpecHelper
   2   class Eat
   3     def initialize(food)
   4       @food = food
   5     end
   6
   7     def matches?(animal)
   8       @animal = animal
   9       @animal.eats?(@food)
  10     end
  11
  12     def failure_message
  13       "expected #{@animal} to eat #{@food}, but it does not"
  14     end
  15
  16     def negative_failure_message
  17       "expected #{@animal} not to eat #{@food}, but it does"
  18     end
  19   end
  20
  21   def eat(food)
  22     Eat.new(food)
  23   end
  24 end
  25
  26 module Animals
  27   class Animal
  28     def eats?(food)
  29       return foods_i_eat.include?(food)
  30     end
  31   end
  32
  33   class Mouse < Animal
  34     def foods_i_eat
  35       [:cheese]
  36     end
  37   end
  38
  39   describe Mouse do
  40     include AnimalSpecHelper
  41     before(:each) do
  42       @mouse = Animals::Mouse.new
  43     end
  44
  45     it "should eat cheese" do
  46       @mouse.should eat(:cheese)
  47     end
  48
  49     it "should not eat cat" do
  50       @mouse.should_not eat(:cat)
  51     end
  52   end
  53
  54 end