From c1ffe80d61d1b4a71c33128023894a33738f9776 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Skytt=C3=A4?= <ville.skytta@iki.fi>
Date: Mon, 1 Apr 2024 21:45:05 +0000
Subject: [PATCH] fix: bash completion fallback in `nounset` mode

With the shell in `nounset` mode, the intended fallback to filename
completion provokes an error:

```
$ cargo foo <TAB>bash: !opt_var: unbound variable
```
---
 src/etc/cargo.bashcomp.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/etc/cargo.bashcomp.sh b/src/etc/cargo.bashcomp.sh
index c0ba62752c0..dad16dd99e3 100644
--- a/src/etc/cargo.bashcomp.sh
+++ b/src/etc/cargo.bashcomp.sh
@@ -154,7 +154,7 @@ _cargo()
 				else
 					local opt_var=opt__${cmd//-/_}
 				fi
-				if [[ -z "${!opt_var}" ]]; then
+				if [[ -z "${!opt_var-}" ]]; then
 					# Fallback to filename completion.
 					_filedir
 				else