TT#69200 Use sprintf instead of ad-hoc code to 0 fill digits

Which is also around 300% faster:

                Rate had-hoc sprintf
  had-hoc  3508772/s      --    -75%
  sprintf 14084507/s    301%      --

Change-Id: I5ebce0058473f9de08c381739646a20e42308a8f
(cherry picked from commit 561e36d08c)

debian/control

@@ -4,7 +4,14 @@ Priority: optional
 Maintainer: Sipwise Development Team <support@sipwise.com>
 Build-Depends:
  debhelper-compat (= 12),
+ libdata-uuid-perl <!nocheck>,
+ libdata-validate-ip-perl <!nocheck>,
+ libdate-calc-perl <!nocheck>,
+ libdate-manip-perl <!nocheck>,
  libmodule-build-perl,
+ libnet-address-ip-local-perl <!nocheck>,
+ libsys-cpuaffinity-perl <!nocheck>,
+ libuuid-perl <!nocheck>,
 Standards-Version: 3.9.8
 Homepage: https://www.sipwise.com/
 

lib/NGCP/BulkProcessor/Utils.pm

@@ -440,14 +440,8 @@ sub get_year_month_day {
 
 sub zerofill {
   my ($integer,$digits) = @_;
-  my $numberofzeroes = $digits - length($integer);
-  my $resultstring = $integer;
-  if ($digits > 0) {
-    for (my $i = 0; $i < $numberofzeroes; $i += 1) {
-      $resultstring = "0" . $resultstring;
-    }
-  }
-  return $resultstring;
+
+  return sprintf '%0*d', $digits, $integer;
 }
 
 sub trim {

t/Utils.t

@@ -0,0 +1,30 @@
+#!/usr/bin/perl
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+use strict;
+use warnings;
+
+use Test::More tests => 4;
+
+require_ok('NGCP::BulkProcessor::Utils');
+
+NGCP::BulkProcessor::Utils->import(qw(
+    zerofill
+));
+
+# zerofill()
+is(zerofill(0, 4), '0000');
+is(zerofill(25, 4), '0025');
+is(zerofill(1000, 4), '1000');