Question

I have an instance method in String class who call the Array instance method “shuffle”. In order for me to test the method using RSpec, I want to stub it.

vowels = %w(a e i o u y)
vowels.shuffle

I tried:

Array.stub(:shuffle).and_return(%w(a e i o u y))
[].stub(:shuffle).and_return(%w(a e i o u y))

But none work 🙁 I am missing something here ? Mocking maybe ? But what should I mock then…

Thank you.

Answer 1

Use any_instance. For example:

describe "any_instance.stub" do
  it "returns the specified value on any instance of the class" do
    Array.any_instance.stub(:shuffle).and_return(%w(a e i o u y))

    o = Array.new
    o.shuffle.should eq(%w(a e i o u y))
  end
end

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