Re: [PATCH 2/2] [GSOC] interpret-trailer: easy parse trailer value

[ZheNing Hu <adlternative@gmail.com>]

Junio C Hamano <gitster@pobox.com> 于2021年3月21日周日 下午9:57写道：
>
> ZheNing Hu <adlternative@gmail.com> writes:
>
> > Do you think this is appropriate?
> >
> > @@ -370,5 +370,15 @@ int parse_buffer_signed_by_header(const char *buffer,
> >                                   struct strbuf *payload,
> >                                   struct strbuf *signature,
> >                                   const struct git_hash_algo *algop);
> > +/*
> > + * Calling `find_author_by_nickname` to find the "author <email>" pair
> > + * in the most recent commit which matches "--author=name".
> > + *
> > + * Note that `find_author_by_nickname` is not reusable, because it haven't
> > + * reset flags for parsed objects. The only safe way to use
> > `find_author_by_nickname`
> > + * (without rewriting the revision traversal machinery) is to spawn a
> > + * subprocess and do find_author_by_nickname() in it.
> > + */
>
> Telling people not to add any new caller is good, but everything
> after "because" does not make sense to me.
>
> I do not think calling find_author_by_nickname() in a subprocess
> alone would not help somebody who wants to do this, either.  We'd be
> doing a moral equivalent of that call, but the result has to be
> communicated back to the parent process,
>

What I am thinking about here is that `commit --trailer` itself jumps to a
sub-process to do this, but this does depend on the fact that
`interpret-trailers`
 itself does not have a traversal, and indeed should not be arbitrarily call it.

> In the longer term, we'd probably want to have a pre-computed table
> of contributors, like we have precomputed files for reachability
> bitmaps, commit DAG topology, and such, but that is obviously far
> outside of the scope of this series.
>

Indeed this will be a very big project. But `.mailmap` always makes me
feel similar.

> > +const char *find_author_by_nickname(const char *name);