Re: What's cooking in git.git (Jan 2024, #01; Tue, 2)

> On Tue, Jan 02, 2024 at 05:02:35PM -0800, Junio C Hamano wrote:
>
>> * jk/t1006-cat-file-objectsize-disk (2023-12-21) 1 commit
>>   (merged to 'next' on 2023-12-28 at d82812e636)
>>  + t1006: add tests for %(objectsize:disk)
>>
>>  Test update.
>>
>>  Will merge to 'master'.
>>  source: <20231221094722.GA570888@coredump.intra.peff.net>
>
> It looks like this is the original version. I posted a v2 that took
> René's suggestion to swap out the awk for shell, but it got overlooked.
> I'm happy enough either way, but if we want to salvage that effort,
> here's a patch which could go on top:
>
> -- >8 --
> From: René Scharfe <l.s.r@web.de>
> Subject: [PATCH] t1006: prefer shell loop to awk for packed object sizes
>
> To compute the expected on-disk size of packed objects, we sort the
> output of show-index by pack offset and then compute the difference
> between adjacent entries using awk. This works but has a few readability
> problems:
>
>   1. Reading the index in pack order means don't find out the size of an
>      oid's entry until we see the _next_ entry. So we have to save it to
>      print later.
>
>      We can instead iterate in reverse order, so we compute each oid's
>      size as we see it.
>
>   2. Since the awk invocation is inside a text_expect block, we can't
>      easily use single-quotes to hold the script. So we use
>      double-quotes, but then have to escape the dollar signs in the awk
>      script.
>
>      We can swap this out for a shell loop instead (which is made much
>      easier by the first change).
>
> Signed-off-by: Jeff King <peff@peff.net>
> ---
> I gave René authorship since this was his cleverness, but obviously I
> wrote the commit message. Giving an explicit signoff would be nice,
> though.

>
>  t/t1006-cat-file.sh | 14 ++++++++------
>  1 file changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/t/t1006-cat-file.sh b/t/t1006-cat-file.sh
> index 0c2eafae65..5ea3326128 100755
> --- a/t/t1006-cat-file.sh
> +++ b/t/t1006-cat-file.sh
> @@ -1117,14 +1117,16 @@ test_expect_success 'cat-file %(objectsize:disk) with --batch-all-objects' '
>  		while read idx
>  		do
>  			git show-index <"$idx" >idx.raw &&
> -			sort -n <idx.raw >idx.sorted &&
> +			sort -nr <idx.raw >idx.sorted &&
>  			packsz=$(test_file_size "${idx%.idx}.pack") &&
>  			end=$((packsz - rawsz)) &&
> -			awk -v end="$end" "
> -			  NR > 1 { print oid, \$1 - start }
> -			  { start = \$1; oid = \$2 }
> -			  END { print oid, end - start }
> -			" idx.sorted ||
> +			while read start oid rest
> +			do
> +				size=$((end - start)) &&
> +				end=$start &&
> +				echo "$oid $size" ||
> +				return 1
> +			done <idx.sorted ||
>  			return 1
>  		done
>  	} >expect.raw &&