Re: Autotesting (was Re: RFC: Increment and Decrement)

[Eric McDonald <mcdonald at phy dot cmich dot edu>]

On Thu, 24 Jun 2004, Jim Kingdon wrote:

> > I thought that I would probably have to figure out how to instantiate
> > a Lisp stream buffer [. . . etc etc etc and so on]
> 
> Ah yes, but unfortunately for your excuse, this part was written years
> ago by Stan.  There's a function in lisp.c called
> read_form_from_string which has all I needed to write a simple test
> (which I have now checked in).

I see. Thanks for popping the excuse bubble, __I guess. :-)
I will followup with some more tests, hopefully in the next few 
days.

> I'm not sure it affects the lisp.c code, but in general, yeah, these
> kinds of global "crucial data structures and variables" are the bane
> of unit testing.  There are basically two solutions: (1) make the code
> more modular, so it is easier to just set up the part you are testing,
> or (2) as part of the test code, have a bunch of helper methods which
> do various kinds of setup.

I agree with both solutions, and this is pretty much what has been 
lurking in the back of my head, regarding what likely needed to be 
done for better autotesting.

> Generally speaking, I had in mind moving towards a situation where
> each unit test blows away any state which might confuse it, and then
> sets up what it needs to run.

Yes, I completely agree with this goal.

Eric