The problem of rspec predicate matchers

predicate_matchers.rb

require 'rspec/core'

class VeryImportantQuestions
  def self.really?(answer)
    answer == 'Yes. I am telling you.'
  end

  def self.really_really?(answer)
    answer == 'Yes. I am telling you.' ? 42 : nil
  end
end

describe "really?" do
  context "using rspec predicate matchers" do
    context "if someone is telling you" do
      it "should be really really the case and return true" do
        VeryImportantQuestions.really?('Yes. I am telling you.').should be_true
      end
    end
    context "if someone is not sure" do
      it "should return false" do
        VeryImportantQuestions.really?('I am not sure.').should be_false
      end
    end
  end
end

describe "really_really?" do
  context "using rspec predicate matchers" do
    context "if someone is telling you" do
      it "should be really really the case and return true" do
        VeryImportantQuestions.really_really?('Yes. I am telling you.').should be_true
      end
    end
    context "if someone is not sure" do
      it "should return false" do
        VeryImportantQuestions.really_really?('I am not sure.').should be_false
      end
    end
  end

  context "spec'ing the actual output of the method fails" do
    context "if someone is telling you" do
      it "should be really really the case and return true" do
        VeryImportantQuestions.really_really?('Yes. I am telling you.').should == true
      end
    end
    context "if someone is not sure" do
      it "should return false" do
        VeryImportantQuestions.really_really?('I am not sure.').should == false
      end
    end
  end
end