[PATCH 1/1] RFC: git: update to v2.18.0-rc2

[John Keeping]

On Thu, Jun 14, 2018 at 12:52:25AM +0200, Christian Hesse wrote:
> From: Christian Hesse <mail at eworm.de>
> 
> Update to git version v2.18.0-rc2. Required changes follow upstream commits:
> 
> * Convert find_unique_abbrev* to struct object_id
>   (aab9583f7b5ea5463eb3f653a0b4ecac7539dc94)
> * sha1_file: convert read_sha1_file to struct object_id
>   (b4f5aca40e6f77cbabcbf4ff003c3cf30a1830c8)
> * sha1_file: convert sha1_object_info* to object_id
>   (abef9020e3df87c441c9a3a95f592fce5fa49bb9)
> * object-store: move packed_git and packed_git_mru to object store
>   (a80d72db2a73174b3f22142eb2014b33696fd795)
> * treewide: rename tree to maybe_tree
>   (891435d55da80ca3654b19834481205be6bdfe33)
> 
> The changed data types required some of our own functions to be converted
> to struct object_id:
> 
>   ls_item
>   print_dir
>   print_dir_entry
>   print_object
>   single_tree_cb
>   walk_tree
>   write_tree_link
> 
> And finally we use new upstream functions that were added for
> struct object_id:
> 
>   hashcpy     -> oidcpy
>   sha1_to_hex -> oid_to_hex
> 
> Signed-off-by: Christian Hesse <mail at eworm.de>

With Andy's fix,

Reviewed-by: John Keeping <john at keeping.me.uk>

It looks like our interface to libgit.a is completely converted to
struct object_id after this update!

But we still have a few mentions of sha1 in our code.  Most of this is
sha1 and sha2 in struct cgit_query, but these aren't actually hashes
most of the time, they can be any object reference that Git understands,
so I think we should rename them to ref1 and ref2 (along with has_sha1
-> has_ref).  What do you think?

(ui-blob does require sha1 to be hex, but it's a bit of a special case
anyway and I think it's fine to impose an extra requirement there.)

After that, I think all that's left is parsing.c and there's no reason
to do anything there until we now how newhash will alter the commit and
tag object encodings.