Bug 10462: (follow-up) remove some undefined variable warning noise

Signed-off-by: Galen Charlton <gmc@esilibrary.com>

diff --git a/C4/Breeding.pm b/C4/Breeding.pm
index 55069db..9527f0f 100644 (file)
--- a/C4/Breeding.pm
+++ b/C4/Breeding.pm
@@ -443,7 +443,8 @@ sub _add_rowdata {
 }
 
 sub _isbn_replace {
-    my ($isbn)= @_;
+    my ($isbn) = @_;
+    return unless defined $isbn;
     $isbn =~ s/ |-|\.//g;
     $isbn =~ s/\|/ \| /g;
     $isbn =~ s/\(/ \(/g;