Re: [PATCH] attr: do not mark queried macros as unset
- From
Jeff King <peff@peff.net>
- Date
- Jan 22, 2019, 07:19 UTC
- Message-ID
- <20190122071921.GC28555@sigill.intra.peff.net>
- In-Reply-To
- <CAGZ79kaPXQUY=FN3qusc2PNs=o1EiNarcBejOQKiozMSPvEOYw@mail.gmail.com>
On Fri, Jan 18, 2019 at 02:19:55PM -0800, Stefan Beller wrote:
Show 5 quoted lines
> > I dunno. This is why I submitted the initial patch as the simplest fix. ;) > > > > The first patch is > Reviewed-by: Stefan Beller <sbeller@google.com>
Thanks!
Show 35 quoted lines
> Diffing across both patches, this seems to be the relevant part:
> [...]
>
> ---8<---
> @@ -1111,14 +1116,13 @@ static void collect_some_attrs(const struct
> index_state *istate,
>
> prepare_attr_stack(istate, path, dirlen, &check->stack);
> all_attrs_init(&g_attr_hashmap, check);
> - determine_macros(check->all_attrs, check->stack);
>
> if (check->nr) {
> rem = 0;
> for (i = 0; i < check->nr; i++) {
> int n = check->items[i].attr->attr_nr;
> struct all_attrs_item *item = &check->all_attrs[n];
> - if (item->macro) {
> + if (!item->attr->in_stack) {
> item->value = ATTR__UNSET;
> rem++;
> }
> @@ -1127,6 +1131,8 @@ static void collect_some_attrs(const struct
> index_state *istate,
> return;
> }
>
> + determine_macros(check->all_attrs, check->stack);
> +
> rem = check->all_attrs_nr;
> fill(path, pathlen, basename_offset, check->stack,
> check->all_attrs, rem);
> }
> ---8<---
>
> which I think is correct.Yes, that's the interesting part. I think I've convinced myself, too, that it doesn't do the _wrong_ thing ever. But I think it misses the point of the original, which is that you want common ones like "diff" not to trigger in_stack if nobody has actually used them. And doing that really does mean marking in_stack not just when a macro mentions it (because clearly "binary" is going to mention it for every repo), but waiting to see if anybody mentions that macro.
Which means we must call determine_macros(), and then propagate the macro's in_stack to its expansion (if it's indeed called at all).
I don't think that would be _too_ hard to do. But I also wonder if there's much point. We are trying to avoid fill(), but I think that determine_macros() is of roughly the same complexity (look at all matches of all stacks). I guess it does avoid path_matches(), which is a bit more expensive. And in theory it could be cached for a particular stack top, so the work is amortized across many path lookups (though I think that gets even more tricky).
-Peff