expects (Mocha::Mock)

        # File lib/mocha/mock.rb, line 38
    38:     def expects(method_name_or_hash, backtrace = nil)
    39:       if method_name_or_hash.is_a?(Hash) then
    40:         method_name_or_hash.each do |method_name, return_value|
    41:           ensure_method_not_already_defined(method_name)
    42:           @expectations.add(Expectation.new(self, method_name, backtrace).returns(return_value))
    43:         end
    44:       else
    45:         ensure_method_not_already_defined(method_name_or_hash)
    46:         @expectations.add(Expectation.new(self, method_name_or_hash, backtrace))
    47:       end
    48:     end