Exploration into how Rspec could provide some of its nice syntactical features

rspec_magic.rb

require 'ostruct'

class Object
  def expect(value)
    @expector = Expector.new(value)
  end

  def eq(val)
    [:==, val]
  end

  def method_missing(meth, *args)
    match = /^be_(.*)/.match(meth)
    if match
      real_method = "#{match[1]}?".to_sym
      [real_method]
    else
      super
    end
  end

  class Expector < Struct.new(:expected_value)
    def to(expectation_args)
      results expected_value.send(*expectation_args)
    end

    def not_to(expectation_args)
      results !expected_value.send(*expectation_args)
    end

    private

    def results(bool)
      puts (bool ? 'PASS!' : 'FAIL!')
    end
  end
end

happy_obj = OpenStruct.new(happy?: true, happiness: 5)
expect(happy_obj).to be_happy            # => PASS!
expect(happy_obj).not_to be_happy        # => FAIL!
expect(happy_obj.happiness).to eq 5      # => PASS!
expect(happy_obj.happiness).to eq 4      # => FAIL!
expect(happy_obj.happiness).not_to eq 4  # => PASS!
expect(happy_obj.happiness).not_to eq 5  # => FAIL!