define_example_attribute.feature

Feature: Define example attribute

In order to streamline process
As an RSpec user
I want to easily define helper methods that act as a variable assignment

It is fairly common to start with a local variable in one example, use the same
local variable in the next, and then extract the declaration of that variable
to before(:each). This requires converting the locals to instance variables.

This feature streamlines the process by defining a helper method so you can extract
the duplication without having to change other references to the same variables
to @instance_variables.

Scenario:
  Given a file named "counter_spec.rb" with:
  """
  require 'spec/autorun'

  class Counter
    def initialize
      @count = 0
    end
    def count
      @count += 1
    end
  end

  describe Counter do
    let(:counter) { Counter.new }
    it "returns 1 the first time" do
      counter.count.should == 1
    end
    it "returns 2 the second time because the counter itself is cached by the 'assign' method" do
      counter.count
      counter.count.should == 2
    end
  end
  """
  When I run "spec counter_spec.rb"
  Then the stdout should include "2 examples, 0 failures"