# File test/unit/assertions.rb, line 88 def assert_instance_of(klass, object, message="") _wrap_assertion do assert_equal(Class, klass.class, "assert_instance_of takes a Class as its first argument") full_message = build_message(message, object, klass, object.class) do |arg1, arg2, arg3| "<#{arg1}> expected to be an instance of\n" + "<#{arg2}> but was\n" + "<#{arg3}>" end assert_block(full_message) { klass == object.class } end end