Subject: Re: [PATCH] [GSOC] ref-filter: solve bugs caused by enumeration

From: Junio C Hamano <[email-masked]>
Date: Fri, 07 May 2021 13:49:47 +0900

ZheNing Hu <[email-masked]> writes:

> But I am afraid that the cost we paid for string matching here is too high,

If that is truly the concern (I do not know without measuring),
perhaps we should add a member next to the union to say which one of
the union members is valid, so that you can say

    if (atom->atom_type == ATOM_TYPE_REMOTE_REF &&
        atom->u.remote_ref.push)

(introduce an enum and define ATOM_TYPE_* after the member in the
union).

That would help futureproofing the code even further, as a new
synonym of "push" introduced laster [*] would not invalidate the check you are
adding there.

[Footnote]

* remote_ref_atom_parser() in the future may begin like so:

-	if (!strcmp(atom->name, "push") || starts_with(atom->name, "push:"))
+	if (!strcmp(atom->name, "push") || starts_with(atom->name, "push:") ||
+           !strcmp(atom->name, "a-synonym-for-push"))
		atom->u.remote_ref.push = 1;