Re: [PATCH 23/29] blame: create entry prepend function

[Junio C Hamano <gitster@pobox.com>]

Jeff Smith <whydoubt@gmail.com> writes:

> Create function that populates a blame_entry and prepends it to a list.
>
> Signed-off-by: Jeff Smith <whydoubt@gmail.com>
> ---
>  builtin/blame.c | 25 +++++++++++++++----------
>  1 file changed, 15 insertions(+), 10 deletions(-)
>
> diff --git a/builtin/blame.c b/builtin/blame.c
> index fd41551..29771b7 100644
> --- a/builtin/blame.c
> +++ b/builtin/blame.c
> @@ -2643,6 +2643,20 @@ void setup_scoreboard(struct blame_scoreboard *sb, const char *path, struct blam
>  		*orig = o;
>  }
>  
> +struct blame_entry *blame_entry_prepend(struct blame_entry *head,
> +					long start, long end,
> +					struct blame_origin *o)
> +{
> +	struct blame_entry *new_head = xcalloc(1, sizeof(struct blame_entry));

We have a slight tendency to favour sizeof(*pointer_to_thing) over
sizeof(type_of_thing), which is why the original is written that
way.  The tendency is so slight that if this were a new code, I do
not think we mind it written either way, but a patch whose goal is
to move existing code around does not have a justification to change
between the two.

> +	new_head->lno = start;
> +	new_head->num_lines = end - start;
> +	new_head->suspect = o;
> +	new_head->s_lno = start;
> +	new_head->next = head;

On the other hand, naming the variables that receive start/end
anything but start/end was a stupidity in the original code (I can
badmouth the original because it is all my code ;-).  Thanks for
fixing the sloppy naming.

> +	blame_origin_incref(o);
> +	return new_head;
> +}
> +
>  int cmd_blame(int argc, const char **argv, const char *prefix)
>  {
>  	struct rev_info revs;
> @@ -2885,16 +2899,7 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
>  
>  	for (range_i = ranges.nr; range_i > 0; --range_i) {
>  		const struct range *r = &ranges.ranges[range_i - 1];
> -		long bottom = r->start;
> -		long top = r->end;
> -		struct blame_entry *next = ent;
> -		ent = xcalloc(1, sizeof(*ent));
> -		ent->lno = bottom;
> -		ent->num_lines = top - bottom;
> -		ent->suspect = o;
> -		ent->s_lno = bottom;
> -		ent->next = next;
> -		blame_origin_incref(o);
> +		ent = blame_entry_prepend(ent, r->start, r->end, o);
>  	}
>  
>  	o->suspects = ent;