Leave sanitize-commit's $target undefined when no branch is given

It was previously unconditionally set, either to false or to the
branch passed on the command line; but code tests it using
defined($target), which was thus always true. Apparently the intent
was to leave it undefined when no branch was given.

Exposed by configuring my local repositories for picked modules to
have with-pickbot enabled. This script is used as post-commit hook,
passing only one argument, without the extra arguments the Qt Sanity
bot on Gerrit passes, notably the one that supplies $target's value.
The with-pickbot code thus got exercised in a new way, leading to a
bogus warning.

Change-Id: If4e035300d6017a7398e995be96e3dee2a0969ed
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Reviewed-by: Daniel Smith <Daniel.Smith@qt.io>

1 files changed, 2 insertions, 2 deletions

diff --git a/git-hooks/sanitize-commit b/git-hooks/sanitize-commit
index cc757ae..b84e1ab 100755
--- a/git-hooks/sanitize-commit
+++ b/git-hooks/sanitize-commit
@@ -1,5 +1,5 @@
 #! /usr/bin/perl
-# Copyright (C) 2017 The Qt Company Ltd.
+# Copyright (C) 2022 The Qt Company Ltd.
 # Copyright (C) 2014 Petroules Corporation.
 # Contact: http://www.qt.io/licensing/
 #
@@ -23,7 +23,7 @@ my $sha1 = $ARGV[0];
 my $gerrit_rest = ($#ARGV >= 1 && $ARGV[1] eq "gerrit-rest");
 my $strict = $gerrit_rest || ($#ARGV >= 1 && $ARGV[1] eq "strict");
 my $instance = ($#ARGV >= 2) ? $ARGV[2] : "default";
-my $target = $#ARGV == 3 && $ARGV[3];
+my $target = $#ARGV == 3 ? $ARGV[3] : undef;
 
 my $repo = getcwd();
 $repo =~ s,/?\.git$,,;