Sometimes your RSpec examples need an easy way to share reusable code. The best way to accomplish this is with Helpers. Helpers are basically regular Ruby methods which you share across examples. To illustrate the benefit of using helpers, let’s consider this code −
class Dog
attr_reader :good_dog, :has_been_walked
def initialize(good_or_not)
@good_dog = good_or_not
@has_been_walked = false
end
def walk_dog
@has_been_walked = true
end
end
describe Dog do
it 'should be able to create and walk a good dog' do
dog = Dog.new(true)
dog.walk_dog
expect(dog.good_dog).to be true
expect(dog.has_been_walked).to be true
end
it 'should be able to create and walk a bad dog' do
dog = Dog.new(false)
dog.walk_dog
expect(dog.good_dog).to be false
expect(dog.has_been_walked).to be true
end
end
This code is clear, but it’s always a good idea to reduce repeated code whenever possible. We can take the above code and reduce some of this repetition with a helper method called create_and_walk_dog().
class Dog
attr_reader :good_dog, :has_been_walked
def initialize(good_or_not)
@good_dog = good_or_not
@has_been_walked = false
end
def walk_dog
@has_been_walked = true
end
end
describe Dog do
def create_and_walk_dog(good_or_bad)
dog = Dog.new(good_or_bad)
dog.walk_dog
return dog
end
it 'should be able to create and walk a good dog' do
dog = create_and_walk_dog(true)
expect(dog.good_dog).to be true
expect(dog.has_been_walked).to be true
end
it 'should be able to create and walk a bad dog' do
dog = create_and_walk_dog(false)
expect(dog.good_dog).to be false
expect(dog.has_been_walked).to be true
end
end
When you run the above code, you will see this output −
.. Finished in 0.002 seconds (files took 0.11401 seconds to load) 2 examples, 0 failures
As you can see, we were able to push the logic for creating and walking a dog object into a Helper which allows our examples to be shorter and cleaner.