Running this spec raises an ArgumentError: wrong number of arguments (2 for 0) at line 9.

message_test.rb

require "rubygems"
require "minitest/autorun"

describe "#let" do
  describe "problematic names" do
    let(:message) { "It is my message" }

    it "is not accessible" do
      message.must_equal "It is my message"
    end
  end
end