[PATCH 4/1] t3920: replace two cats with a tee

["René Scharfe" <l.s.r@web.de>]

Use tee(1) to replace two calls of cat(1) for writing files with
different line endings.  That's shorter and spawns less processes.

It has a small, but measurable performance impact on my Windows machine.
Here are the numbers before:

   $ (cd t && hyperfine.exe -w3 "sh.exe t3920-crlf-messages.sh")
   Benchmark 1: sh.exe t3920-crlf-messages.sh
     Time (mean ± σ):      5.705 s ±  0.047 s    [User: 0.000 s, System: 0.001 s]
     Range (min … max):    5.632 s …  5.772 s    10 runs

... and with this patch:

   $ (cd t && hyperfine.exe -w3 "sh.exe t3920-crlf-messages.sh")
   Benchmark 1: sh.exe t3920-crlf-messages.sh
     Time (mean ± σ):      5.616 s ±  0.021 s    [User: 0.001 s, System: 0.002 s]
     Range (min … max):    5.577 s …  5.644 s    10 runs

Signed-off-by: René Scharfe <l.s.r@web.de>
---
 t/t3920-crlf-messages.sh | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/t/t3920-crlf-messages.sh b/t/t3920-crlf-messages.sh
index 4fc9fa9cad..1f64ce565f 100755
--- a/t/t3920-crlf-messages.sh
+++ b/t/t3920-crlf-messages.sh
@@ -9,8 +9,7 @@ LIB_CRLF_BRANCHES=""

 create_crlf_ref () {
 	branch="$1" &&
-	cat >.crlf-orig-$branch.txt &&
-	cat .crlf-orig-$branch.txt | append_cr >.crlf-message-$branch.txt &&
+	tee .crlf-orig-$branch.txt | append_cr >.crlf-message-$branch.txt &&
 	grep 'Subject' .crlf-orig-$branch.txt | tr '\n' ' ' | sed 's/[ ]*$//' | tr -d '\n' >.crlf-subject-$branch.txt &&
 	grep 'Body' .crlf-orig-$branch.txt | append_cr >.crlf-body-$branch.txt &&
 	LIB_CRLF_BRANCHES="${LIB_CRLF_BRANCHES} ${branch}" &&
--
2.38.1.windows.1