From 3d3fc8282be218429403d7a4132c08628b4a42bd Mon Sep 17 00:00:00 2001
From: Yves Orton <demerphq@gmail.com>
Date: Mon, 13 Mar 2023 12:30:38 +0100
Subject: [PATCH] Test2::Util - add _env_get() to wrap %ENV access.

A test might lock %ENV, so we should always check for key existence
before reading a key, or the lookup might trigger an exception. This
function wraps the check up and provides a default facility to make
logic that needs to consult %ENV more robust.
---
 lib/Test2/Util.pm | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/lib/Test2/Util.pm b/lib/Test2/Util.pm
index 9ce991ccf..a19e5a219 100644
--- a/lib/Test2/Util.pm
+++ b/lib/Test2/Util.pm
@@ -36,6 +36,8 @@ our @EXPORT_OK = qw{
     try_sig_mask
 
     clone_io
+
+    _env_get
 };
 BEGIN { require Exporter; our @ISA = qw(Exporter) }
 
@@ -43,6 +45,17 @@ BEGIN {
     *IS_WIN32 = ($^O eq 'MSWin32') ? sub() { 1 } : sub() { 0 };
 }
 
+# check for key existence before fetching from %ENV to avoid
+# locked hash issues. If it does not exist, or it does and the
+# value is undefined return $_[1] instead, thus allowing
+# a default value to be supplied if required.
+sub _env_get {
+    my ($key,$default) = @_;
+    my $got = exists($ENV{$key}) ? $ENV{$key} : undef;
+    $got = $default unless defined $got;
+    return $got;
+}
+
 sub _can_thread {
     return 0 unless $] >= 5.008001;
     return 0 unless $Config{'useithreads'};