Re: [PATCH] CONTRIBUTE - writing tests for understanding internals

["Przemysław Wojnowski" <esperanto@cumego.com>]

W dniu 11.11.2015 o 16:40, Eli Zaretskii pisze:
 >> From: Przemysław Wojnowski <esperanto@cumego.com>
 >> Cc: emacs-devel@gnu.org
 >> Date: Wed, 11 Nov 2015 08:45:23 +0100
 >>
 >>> Thanks, but I don't think CONTRIBUTE is the right place for
 >>> motivation-related text.  We should find some other place for that.
 >>
 >> This was not for motivational purposes, but to tell how to learn about
 >> Emacs Internals - like the old part.
 >
 > The style is quite different: where CONTRIBUTE is about information
 > for contributors, the suggested change, with the exception of its
 > first sentence, is a motivational text that has no informational value
 > for contributors.
I tend to agree that my style of writing is different than the rest of
the document and is a place to improve. That's why I've sent it here.

 > More importantly, I disagree with your posit that writing tests is a
 > good way of learning about Emacs internals.
Did you write this based on your experience? I did.

It *is* very good way to learn about a project and, in many companies,
is used to introduce new developers. (I do that every time and after
sometime devs tell me that it is a good introduction, because project
at the beginning were to big and overwhelming to them.)

It's very easy to verify this by writing a few tests to a project you
don't know.

 > Best tests are written by looking at the spec alone,
 > because looking at the implementation will bias you when
 > you write the test.  That's why tests should ideally be
 > written by someone who is not the implementor.
Ideally yes. And new contributors are very close to this ideal, because
they didn't implement the code and have docs as specs.

I submitted a couple of tests to Emacs packages and was writing them
based on available docs (even CLTL2, in case of cl-lib) and I've
learned a lot about those parts.

 >  I'm sure you are
 > familiar with the TDD methodology, whose strong point is precisely
 > that you write tests before implementing anything.
"Reality check:" we already have code base. ;-)

Cheers,
Przemysław