Re: [PATCH 00/17] Clean up how fetch_pack() handles the heads list

On 08/23/2012 10:31 PM, Jeff King wrote:

I think part of the confusion of this code is that inside the loop over
the refs it is sometimes checking aspects of the ref, and sometimes
checking invariants of the loop (like args.fetch_all). Splitting it into
separate loops makes it easier to see what is going on, like the patch
below (on top of Michael's series).

I'm not sure if it ends up being more readable, since the generic "cut
down this linked list" function has to operate through callbacks with a
void pointer. On the other hand, that function could also be used
elsewhere.
[...]

Despite requiring a bit more boilerplate, I think that your change makes
the logic clearer.

*If* we want to switch to using callbacks, then we can get even more
bang for the buck, as in the attached patch (which applies on top of my
patch v2).  Beyond your suggestion, this patch:

* Inlines your filter_refs() into everything_local(), because (a) it's
short and (b) the policy work implemented there logically belongs
higher-up in the call chain.

* Renames your filter_refs_callback() to filter_refs().

* Moves the initialization of the filter_by_name_data structure
(including sorting and de-duping) all the way up to fetch_pack(), and
passes a filter_by_name_data* (rather than (nr_heads, heads)) down to
the callees.

If you like this change, let me know and I'll massage it into a
digestible patch series.

Michael
-- 
Michael Haggerty
mhagger@alum.mit.edu
http://softwareswirl.blogspot.com/