From ab3621678a582e7bde46482cf970ffb6b1ef154d Mon Sep 17 00:00:00 2001
From: Akim Demaille <akim.demaille@gmail.com>
Date: Mon, 14 Oct 2019 07:58:36 +0200
Subject: [PATCH] tests: use a portable 'truncate' implementation

Suggested by Paul Eggert.
https://lists.gnu.org/archive/html/bison-patches/2019-10/msg00044.html

* tests/local.at (AT_DATA_NO_FINAL_EOL): Use dd instead of perl.
---
 tests/local.at | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tests/local.at b/tests/local.at
index a753f13f..5027ec55 100644
--- a/tests/local.at
+++ b/tests/local.at
@@ -57,7 +57,11 @@ m4_define([AT_SETUP_STRIP],
 m4_define([AT_DATA_NO_FINAL_EOL],
 [AT_DATA([$1], [$2
 ])
-AT_PERL_REQUIRE([[-pi -e 'chomp if eof' $1]])
+AT_REQUIRE([
+set x $(LC_ALL=C ls -l '$1') &&
+  size=$][6 &&
+  { test $size -eq 0 || dd obs=1 seek=`expr $size - 1` if=/dev/null of='$1'; }],
+  [], [ignore], [ignore])
 ])