Re: [PATCH] revision: add --except option

From: Felipe Contreras <felipe.contreras@gmail.com>
Date: Aug 31, 2013, 19:27 UTC
Message-ID: <CAMP44s0D98tggTjQsMn+-03KgSsbrh3nxYfLofpC1gfnJpEPyw@mail.gmail.com>
In-Reply-To: <5220503F.2080608@viscovery.net>

On Fri, Aug 30, 2013 at 2:56 AM, Johannes Sixt <j.sixt@viscovery.net> wrote:

Show 16 quoted lines

> Am 8/30/2013 8:32, schrieb Junio C Hamano:
>> If you have a history where
>>
>>  - branches "master" and "maint" point at commit A;
>>  - branch "next" points at commit B that is a descendant of A; and
>>  - there are tags X and Y pointing at commits that are ahead of B
>>    or behind A
>>
>> i.e.
>>
>>       ----X----A----B----Y
>>
>> what are the desired semantics for these?
>
> I think the simplest were that --except trumps everything and means
> "whatever else I say, do as if I did not mention the following".

Actually, my patch is almost there, I attach the necessary changed below to make everything work. I've added debug prints to show what it's actually doing:

>>  (1) --branches --except maint
>
> => master next

=> master next

>>  (2) --all --not --branches --except maint
>
> => X Y --not master next

=> ^master ^next X Y HEAD

>>  (3) ^master next --except maint
>
> => ^master next

=> ^master next

> (4) Y next --except master next --not --branches
>
> this => Y --not maint
> or this => Y --not maint master next

=> Y

Remember that maint (or rather ^maint) is after --except.

Show 5 quoted lines

> (5) --branches --except ^master
>
> this => maint next
> or this => maint master next ^master
> or error("--except does not allow negated revisions")

=> maint next

Here's the diff:

--- a/revision.c
+++ b/revision.c
@@ -2578,7 +2578,11 @@ void reset_revision_walk(void)
 static int refcmp(const char *a, const char *b)
 {
        a = prettify_refname(a);
+       if (*a == '^')
+               a++;
        b = prettify_refname(b);
+       if (*b == '^')
+               b++;
        return strcmp(a, b);
 }

@@ -2594,13 +2598,14 @@ int prepare_revision_walk(struct rev_info *revs)
        revs->pending.alloc = 0;
        revs->pending.objects = NULL;
        while (--nr >= 0) {
-               struct commit *commit = handle_commit(revs, e->item, e->name);
+               struct commit *commit;
                for (i = 0; i < revs->cmdline.nr; i++) {
                        struct rev_cmdline_entry *ce;
                        ce = &revs->cmdline.rev[i];
                        if ((ce->flags & SKIP) && !refcmp(ce->name, e->name))
                                goto next;
                }
+               commit = handle_commit(revs, e->item, e->name);
                if (commit) {
                        if (!(commit->object.flags & SEEN)) {
                                commit->object.flags |= SEEN;

-- 
Felipe Contreras