From ac7f3d61827cfec89fb475d3334ca5afc2201b64 Mon Sep 17 00:00:00 2001
From: Mike McQuaid <mike@mikemcquaid.com>
Date: Thu, 9 Jan 2025 12:25:10 +0000
Subject: [PATCH] bin/brew: handle unbound variable.

This can fail when running `bin/brew` under `set -u`.
---
 bin/brew | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bin/brew b/bin/brew
index 294091fe81..0135257ad7 100755
--- a/bin/brew
+++ b/bin/brew
@@ -150,7 +150,7 @@ export_homebrew_env_file() {
     do
       [[ "${line}" = "${VAR}"* ]] && invalid_variable="${VAR}"
     done
-    [[ -n "${invalid_variable}" ]] && continue
+    [[ -n "${invalid_variable:-}" ]] && continue
 
     export "${line?}"
   done <"${env_file}"