test_common: avoid uninitialized warning on readlink

Of course, waiting for inotify to become active can't rely on
inotify, so we need to do a busy loop here, instead...

diff --git a/lib/PublicInbox/TestCommon.pm b/lib/PublicInbox/TestCommon.pm
index 943dd2fa9d111c85f1222a9e853264af20bb4205..ecf7a261b6f485447dce78ca6f10fd74660f4201 100644 (file)
--- a/lib/PublicInbox/TestCommon.pm
+++ b/lib/PublicInbox/TestCommon.pm
@@ -378,7 +378,7 @@ sub wait_for_tail {
                my @ino;
                do {
                        @ino = grep {
-                               readlink($_) =~ /\binotify\b/
+                               (readlink($_) // '') =~ /\binotify\b/
                        } glob("/proc/$tail_pid/fd/*");
                } while (!@ino && time <= $end and tick);
                return if !@ino;