Subject: Re: What's cooking in git.git (Apr 2013, #05; Mon, 15)

From: Junio C Hamano <[email-masked]>
Date: Wed, 17 Apr 2013 16:56:30 -0700

Felipe Contreras <[email-masked]> writes:

> And how do you know this will be part of the 1%? You don't. How many
> times have you tracked regressions in transport helper's import/export
> functionality? How many times in remote-hg? How many times has
> *anybody* done so?

The last point makes it all the more important to have a good
history [*1*]. An area that no developer rarely touches with a little
user base can stay dormant for a long time, and when people do need
to hunt for an ancient bug or to enhance the existing feature to
support a new use case without breaking the old use case, the
original author may not be around, lost interest, or no longer uses
his own creation.

The code left behind tells us what the author thought was the best
way to solve his problem, but it does not clearly define what the
problem he tried to solve was, within what constraint he had to find
a solution for it, and why he thought that the solution was the best
(or sometimes "only") one.  Log and in-code comments are to explain
such things that are beyond how the code works and what it does.

[Footnote]

*1* In this message, I am not judging if the depth of your writing
    for the particular change is deep enough. It depends on how well
    the reader knows the area, and there is no single right answer
    to that question.
    
    Incidentally that is why we tend to err on the more descriptive
    side. The next person your commit will help may not know the
    area as well as you do and has to figure things out on his
    own. You are helping him by being descriptive.