Subject: Re: [PATCH 1/6] Add docstrings for lookup_replace_object() and do_lookup_replace_object()

From: Junio C Hamano <[email-masked]>
Date: Fri, 21 Feb 2014 10:21:20 -0800

Michael Haggerty <[email-masked]> writes:

> Signed-off-by: Michael Haggerty <[email-masked]>
> ---
>  cache.h | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
>
> diff --git a/cache.h b/cache.h
> index dc040fb..0ecd1c8 100644
> --- a/cache.h
> +++ b/cache.h
> @@ -788,13 +788,29 @@ static inline void *read_sha1_file(const unsigned char *sha1, enum object_type *
>  {
>  	return read_sha1_file_extended(sha1, type, size, LOOKUP_REPLACE_OBJECT);
>  }
> +
> +/*
> + * If a replacement for object sha1 has been set up, return the
> + * replacement object's name (replaced recursively, if necessary).
> + * The return value is either sha1 or a pointer to a
> + * permanently-allocated value.  This function always respects replace
> + * references, regardless of the value of check_replace_refs.
> + */
>  extern const unsigned char *do_lookup_replace_object(const unsigned char *sha1);
> +
> +/*
> + * If object sha1 should be replaced, return the replacement object's
> + * name.  This function is similar to do_lookup_replace_object(),
> + * except that it when object replacement is suppressed, it always
> + * returns its argument unchanged.
> + */
>  static inline const unsigned char *lookup_replace_object(const unsigned char *sha1)
>  {
>  	if (!read_replace_refs)
>  		return sha1;
>  	return do_lookup_replace_object(sha1);
>  }
> +
>  static inline const unsigned char *lookup_replace_object_extended(const unsigned char *sha1, unsigned flag)
>  {
>  	if (!(flag & LOOKUP_REPLACE_OBJECT))

The above description is good, but after reading e1111cef (inline
lookup_replace_object() calls, 2011-05-15) that introduced this
ugliness, I have to wonder if do_lookup_replace(), which nobody
except lookup_replace_object() ever calls, is better removed from
the public API, making lookup_replace_object() an extern definition.

We do name functions that are purely helpers that are internal
implementation detals of the API as "do_blah", but exporting that
kind of name as if that is part of the API people are expected to
call feels very wrong.