Re: git history tracking across renames (and emacs support)

[Ted Zlatanov]

On Tue, 10 Jul 2018 18:36:23 +0300 Eli Zaretskii <address@hidden> wrote: 

>> From: Ted Zlatanov <address@hidden>

>> I would appreciate that too. If I need to know what functions were
>> modified, I look at the diff, which Git makes trivial.
>> 
>> Is there any chance of evolving the commit message formatting
>> requirements to lower the friction of making a commit and reduce
>> redundancy?

EZ> IMO, what you'd like to have will actually _raise_ the friction
EZ> (i.e. will be harder to provide) for many contributors, according to
EZ> my experience of reviewing quite a few patches.

I really don't think the current format is easy for anyone, especially
new developers. It's also essentially repeating the headers from the
diff.

Anecdotally, every time I want to make a larger commit with a lot of
items, it feels to me like paperwork for its own sake and takes up a
long time.

Let's take a recent example.

commit 2fde6275b69fd113e78243790bf112bbdd2fe2bf
Author: Basil L. Contovounesios <address@hidden>
Date:   Mon Jul 9 18:46:33 2018 -0700

    Add predicate proper-list-p
    
    For discussion, see emacs-devel thread starting at
    https://lists.gnu.org/archive/html/emacs-devel/2018-04/msg00460.html.
    
    * lisp/subr.el (proper-list-p): New function.
    Implementation suggested by Paul Eggert <address@hidden> in
    https://lists.gnu.org/archive/html/emacs-devel/2018-06/msg00138.html.
    * doc/lispref/lists.texi (List Elements):
    * etc/NEWS: Document proper-list-p.
    * lisp/org/ob-core.el (org-babel-insert-result):
    * lisp/emacs-lisp/byte-opt.el (byte-optimize-if):
    * lisp/emacs-lisp/cl-macs.el (cl--make-usage-args): Use proper-list-p.
    * lisp/emacs-lisp/ert.el (ert--proper-list-p): Remove.
    Replaced by proper-list-p in lisp/subr.el.
    (ert--explain-equal-rec): Use proper-list-length.
    * lisp/format.el (format-proper-list-p): Remove.
    Replaced by proper-list-p in lisp/subr.el.
    (format-annotate-single-property-change): Use proper-list-p.
    * test/lisp/emacs-lisp/ert-tests.el (ert-test-proper-list-p):
    Move from here...
    * test/lisp/subr-tests.el (subr-tests--proper-list-length):
    ...to here, mutatis mutandis.

Here's one way to write it more concisely and make it more readable,
keeping in mind that the diff is part of the same log and is thus going
to be right below the explanation, and Git usually already *knows* which
files and functions have been modified. I'd much rather read the second
version.

commit 2fde6275b69fd113e78243790bf112bbdd2fe2bf
Author: Basil L. Contovounesios <address@hidden>
Date:   Mon Jul 9 18:46:33 2018 -0700

    Adds and documents the new predicate function proper-list-p

    Factors out several one-off implementations of the same functionality.
    For discussion, see emacs-devel thread starting at
    https://lists.gnu.org/archive/html/emacs-devel/2018-04/msg00460.html.

    Implementation suggested by Paul Eggert <address@hidden> in
    https://lists.gnu.org/archive/html/emacs-devel/2018-06/msg00138.html.