Re: next bugfix release?

[Eric M. Ludlam]

On Thu, 2009-08-20 at 11:02 +0200, Lennart Borgman wrote:
> On Thu, Aug 20, 2009 at 1:16 AM, Nick Roberts<address@hidden> wrote:
> >  > Yes.  It's one of these @dfn{wallpaper paste} bugs, where when you press
> >  > an area of wallpaper firmly to the wall, the paste under it pops up
> >  > another bit of wallpaper somewhere else.  It's going to be a horrible bug
> >  > to fix.  Indeed, it may not be fixable, in the sense of doing the Right
> >  > Thing under every reasonable circumstance.
> >
> > Such 'bubbles', usually called regressions, might be less likely to appear
> > if, as Cyd suggested, there was a CC mode equivalent of compilation.txt.
> > I can't find this post now, so apologies if it reached a logical conclusion.
> > It might also be harder to implement than compilation.txt, as expressions
> > are probably not as self contained, but some kind of testuite seems 
> > essential
> > to prevent these issues from recurring.
> 
> 
> Is not some kind of unit tests what we want here?
> 
> Adding a unit test for at least every serious and difficult bug seems
> to me the right thing to do.
> 
> 
> There are some unit tests frameworks on EmacsWiki. I have one modified
> version of one of these in nXhtml. And CEDET has some unit tests
> (which I have not looked at but I have run the test suite).

Just as another vote for testing, CEDET floundered for a long time with
performance and accuracy issues (say from 1996 through 2007 or so) until
I started adding test suites.  Ever since, I've been able to do sweeping
changes to the underpinnings for performance, bugs or new features, and
know that everything still works by running a single "make" command.
Every user reported bug I fix gets a new test in one of the pre-existing
test suites as I work on the bug, and several folks on the mailing list
now are very good at providing test snippets for me, keeping maintenance
and overhead low.

I highly recommend doing the same for any complex task in Emacs.

Eric