#user_test.rb def test_full_name assert_equal 'John Doe', full_name('John', nil, 'Doe'), "nil middle initial" assert_equal 'John H. Doe', full_name('John', 'H', 'Doe'), "H middle initial" assert_equal 'John Doe', full_name('John', '', 'Doe'), "blank middle initial" end def full_name(first, middle, last) User.new(:first_name => first, :middle_initial => middle, :last_name => last).full_name end