In RSpec, how can one pass an instance variable to an example block?

I am using some spec_helper.rb methods to generate RSpec examples and one of them is dependent on data from another one.

Example spec_helper.rb:

def it_should_be_big(objects)
  @tested_objects ||= []

  objects.each do |obj|
    it "should be big (#{obj.name})" do
      obj.should be_big
    end
  end

  @tested_objects += objects
end

def it_should_be_small(objects)
  @tested_objects ||= []

  objects.each do |obj|
    it "should be small (#{obj.name})" do
      obj.should be_small
    end
  end

  @tested_objects += objects
end

def it_should_have_tested_for_all_objects
  it "should test for all objects" do
    @tested_objects ||= []

    (all_objects - @tested_objects).should == []

    @tested_objects = []
  end
end开发者_如何学JAVA

Example something_spec.rb:

describe "something" do
  it_should_be_big(some_objects)
  it_should_be_small(some_other_objects)

  it_should_have_tested_for_all_objects
end

I know the code does not make much sense but it follows the actual code where it matters (the @tested_objects variable).

When I run the specs, it can't find the @tested_objects variable (I guess it uses another variable space for inside the example blocks). Is there a way to pass the variable to inside the example block of the final helper method?

RSpec 2.5, Rails 3.0.4, Ruby 1.8.7

Depending on the situation you may want before or share_examples_for.

workaround: it seems that only local variables are seen by the it. Then you can try this:

def it_should_have_tested_for_all_objects
  @tested_objects ||= []

  tested_objects = @tested_objects
  it "should test for all objects" do
    (all_objects - tested_objects).should == []
  end

  @tested_objects = []
end