Re: Recommendation for consistent update on invoke of "sha1_to_hex()"

[Jeff King <peff@peff.net>]

On Fri, Jan 05, 2018 at 11:26:01AM +0800, 牛旭 wrote:

> By mining historical patches, we suggest that invokes of sha1_to_hex()
> should be replaced with that of oid_to_hex(). One example for
> recommendation and corresponding patch are listed as follows. 

Note that these two functions take different types. If you only have a
"const unsigned char *", then you must use sha1_to_hex(). If you have a
"struct object_id", then you should be using oid_to_hex(). If there are
sites which do:

  sha1_to_hex(oid.hash)

those should be converted to use oid_to_hex(). I think there's a
coccinelle rule for this, though, so there shouldn't be any lingering
calls like that.

Of course the ultimate goal is for every function to use oid_to_hex().
But that's much bigger than a single-line change, since groups of
dependent functions need to be converted (try "git log
--author=carlson" to see example patches).

> One example of missed spot:
> 1  void assert_sha1_type(const unsigned char *sha1, enum 
>   object_type expect)
> 2 {
> 3  enum object_type type = sha1_object_info(sha1, NULL);
> 4  if (type < 0)
> 5   die("%s is not a valid object",sha1_to_hex(sha1));
> 6  if (type != expect)
> 7   die("%s is not a valid '%s' object", sha1_to_hex(sha1),
> 8  typename(expect));
> 9 }

So this is an example that doesn't convert easily. The function has only
the bare pointer, so you'd have to change its parameter list (and
therefore all of its callers).

-Peff