From 5a52015232f6c9611c5519400afd5cd58fd9021a Mon Sep 17 00:00:00 2001
From: Tatsuhiko Miyagawa <tmiyagawa@fastly.com>
Date: Thu, 14 Sep 2023 14:41:20 -0700
Subject: [PATCH] use ref to avoid calling overloaded methods. Fix #697

---
 lib/Plack/Middleware/StackTrace.pm | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/Plack/Middleware/StackTrace.pm b/lib/Plack/Middleware/StackTrace.pm
index 9c02c109c..d0821e53c 100644
--- a/lib/Plack/Middleware/StackTrace.pm
+++ b/lib/Plack/Middleware/StackTrace.pm
@@ -55,7 +55,8 @@ sub call {
         $trace = $caught_trace if $caught_trace;
     }
 
-    if ($trace && ($caught || ($self->force && ref $res eq 'ARRAY' && $res->[0] == 500)) ) {
+    # Use ref $trace to avoid calling as_string twice when it's not necessary
+    if (ref $trace && ($caught || ($self->force && ref $res eq 'ARRAY' && $res->[0] == 500)) ) {
         my $text = $trace->as_string;
         my $html = $trace->as_html;
         $env->{'plack.stacktrace.text'} = $text;