From: Ron Jeffries <ronjeffries@...>
Date: 2001-12-16T04:14:25+09:00
Subject: [ruby-talk:28638] Re: test-first

On Sat, 15 Dec 2001 15:36:04 GMT, Daniel <notdanielt3@gte.net> wrote:

>In the first case, your talking about collision detection. No automated
>test can be devised for that, a person has to look at the screen and
>decide if the ball should have changed directions, or continued on its
>course.

I believe I could write an automated test for collision detection.
What am I missing?
>
>In the second, the computer doesn't know an item is there unless the
>programmer told it, and the programmer doesn't know someone wants to
>pick it up until a tester tries... Now you might say that we can make
>automated tests to ensure that the user can pick up things that the
>programmer told it was "gettable", but making sure that works is
>trivial, so what is the point of writing a test for it?

I have used games that had defects such that things that should be
gettable weren't, and other interactions with the environment that
should be possible were not.

That fact is the point of writing tests for such things. When we don't
test, we get defects. Manual testing can be harder than automated, and
less reliable in repetition, so it is often to be preferred. But some
kind of testing (or equivalent verification) seems to be necessary for
most programmers to produce code that actually works.

Regards,

Ronald E Jeffries
http://www.XProgramming.com
http://www.objectmentor.com