Re: [PATCH v6 0/5] t: test cleanup stemming from experimentally enabling pipefail

>
> Range-diff against v5:
> 1:  a99a45cb6f ! 1:  3008ce8deb t7700: consolidate code into test_no_missing_in_packs()
>     @@ Commit message
>          Refactor the resulting extraction so that if any git commands fail,
>          their return codes are not silently lost.
>      
>     -    We were using sed to filter lines. Although not incorrect, this is
>     -    exactly what grep is built for. Replace this invocation of sed with grep
>     -    so that we use the correct tool for the job.
>     -
>          Instead of verifying each file of `alt_objects/pack/*.idx` individually
>          in a for-loop, batch them together into one verification step.
>      
>          The original testing construct was O(n^2): it used a grep in a loop to
>          test whether any objects were missing in the packfile. Rewrite this to
>     -    sort the files then use `comm -23` so that finding missing lines from
>     -    the original file is done more efficiently.
>     +    extract the hash using sed or cut, sort the files, then use `comm -23`
>     +    so that finding missing lines from the original file is done more
>     +    efficiently.
>      
>          While we're at it, add a space to `commit_and_pack ()` for style.
>      
>     @@ t/t7700-repack.sh: test_description='git repack works correctly'
>      +	myidx=$(ls -1 .git/objects/pack/*.idx) &&
>      +	test_path_is_file "$myidx" &&
>      +	git verify-pack -v alt_objects/pack/*.idx >orig.raw &&
>     -+	grep "^[0-9a-f]\{40\}" orig.raw | cut -d" " -f1 | sort >orig &&
>     ++	sed -n -e "s/^\([0-9a-f]\{40\}\).*/\1/p" orig.raw | sort >orig &&
>      +	git verify-pack -v $myidx >dest.raw &&
>      +	cut -d" " -f1 dest.raw | sort >dest &&
>      +	comm -23 orig dest >missing &&

> 2:  f79240e937 = 2:  f3a0470edc t7700: consolidate code into test_has_duplicate_object()
> 3:  632a62f6e9 = 3:  c34477a5a9 t7700: replace egrep with grep
> 4:  bf70cc5a0d ! 4:  113f375192 t7700: make references to SHA-1 generic
>     @@ t/t7700-repack.sh: test_description='git repack works correctly'
>       	myidx=$(ls -1 .git/objects/pack/*.idx) &&
>       	test_path_is_file "$myidx" &&
>       	git verify-pack -v alt_objects/pack/*.idx >orig.raw &&
>     --	grep "^[0-9a-f]\{40\}" orig.raw | cut -d" " -f1 | sort >orig &&
>     -+	grep "^$OID_REGEX" orig.raw | cut -d" " -f1 | sort >orig &&
>     +-	sed -n -e "s/^\([0-9a-f]\{40\}\).*/\1/p" orig.raw | sort >orig &&
>     ++	sed -n -e "s/^\($OID_REGEX\).*/\1/p" orig.raw | sort >orig &&