Re: [PATCH 05/10] diff.c: reintroduce diff_flush_patch for all files

From: Junio C Hamano <gitster@pobox.com>
Date: Sep 13, 2016, 00:05 UTC
Message-ID: <xmqqsht4wtns.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <1473572530-25764-6-git-send-email-stefanbeller@gmail.com>

Stefan Beller <stefanbeller@gmail.com> writes:

> From: Stefan Beller <sbeller@google.com>
>
> ---

This shows why 04/10 should have had the overall plan for these two steps. We want a short-and-sweet name "diff-flush-patch" to mean "flush all the queued diff elements" so rename the singleton one from diff-flush-patch to diff-flush-patch-filepair to make room in 04/10 and then introduce the "diff-flush-patch-all" in 05/10.

I just said with the above explanation the changes in 04/10 and 05/10 become undertandable, which is a bit different from being justifiable. "diff_flush_raw()", "diff_flush_stat()", etc. are _all_ about a single filepair. I'd rather see diff_flush_patch() to be also about a single filepair.

It may be helpful to have a helper that calls diff_flush_patch() for all filepairs in the queue, but can't that function get a new name instead? By definition, it will be called much less often than a pair-wise one, so it can afford to have a longer name.

diff_flush_patch_queue() or something, perhaps? I am not sure if it should be diff_flush_queue_patch(), or even

    diff_flush_queue(struct diff_options *o, diff_flush_fn fn);

where diff_flush_fn is

    typedef void (*diff_flush_fn)(struct diff_filepair *p,
    			struct diff_options *o, void *other_data)

that can be used to flush the queue by calling any of these filepair-wise flush functions like diff_flush_{raw,stat,checkdiff,patch}.

This last approach might be overkill, but if you want to try it, you'd need a preparatory step to give an unused "void *other" to diff_flush_{raw,patch,checkdiff} as diff_flush_stat() is an oddball that needs an extra "accumulator" pointer. I actually wonder if that "diffstat" pointer should become part of "struct diff_options", though. Anyway.

Show 38 quoted lines

>  diff.c | 17 ++++++++++++-----
>  1 file changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/diff.c b/diff.c
> index 85fb887..87b1bb2 100644
> --- a/diff.c
> +++ b/diff.c
> @@ -4608,6 +4608,17 @@ void diff_warn_rename_limit(const char *varname, int needed, int degraded_cc)
>  		warning(rename_limit_advice, varname, needed);
>  }
>  
> +static void diff_flush_patch(struct diff_options *o)
> +{
> +	int i;
> +	struct diff_queue_struct *q = &diff_queued_diff;
> +	for (i = 0; i < q->nr; i++) {
> +		struct diff_filepair *p = q->queue[i];
> +		if (check_pair_status(p))
> +			diff_flush_patch_filepair(p, o);
> +	}
> +}
> +
>  void diff_flush(struct diff_options *options)
>  {
>  	struct diff_queue_struct *q = &diff_queued_diff;
> @@ -4702,11 +4713,7 @@ void diff_flush(struct diff_options *options)
>  			}
>  		}
>  
> -		for (i = 0; i < q->nr; i++) {
> -			struct diff_filepair *p = q->queue[i];
> -			if (check_pair_status(p))
> -				diff_flush_patch_filepair(p, options);
> -		}
> +		diff_flush_patch(options);
>  	}
>  
>  	if (output_format & DIFF_FORMAT_CALLBACK)