From f649a18a75b164b88072774418c318360dfa3267 Mon Sep 17 00:00:00 2001
From: Zane Duffield <zduffield@integradev.com.au>
Date: Wed, 14 Jan 2026 11:20:55 +1100
Subject: [PATCH] Fix array expansion errors on unknown parameter names

When unexpected parameters are passed to cmdarg, the shell (bash 5.1.8)
spits out some error messages about bad array subscripts, for example

> cmdarg.sh: line 333: CMDARG_FLAGS: bad array subscript
> cmdarg.sh: line 334: CMDARG_FLAGS: bad array subscript
> cmdarg.sh: line 340: CMDARG: bad array subscript

This occurs because the array is being indexed by a null value, so to
prevent it we must guard all such uses with a check.
---
 cmdarg.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/cmdarg.sh b/cmdarg.sh
index d909948..cee3f35 100644
--- a/cmdarg.sh
+++ b/cmdarg.sh
@@ -326,7 +326,7 @@ function cmdarg_parse
                 ${CMDARG_ERROR_BEHAVIOR} 1
             fi
 
-        if [[ $is_equals_arg -eq 1 ]]; then
+        if [[ $is_equals_arg -eq 1 && -n "$opt" ]]; then
             if [[ ${CMDARG_FLAGS[$opt]} -eq ${CMDARG_FLAG_REQARG} ]] || \
                 [[ ${CMDARG_FLAGS[$opt]} -eq ${CMDARG_FLAG_OPTARG} ]]; then
                 optarg=$1
@@ -334,7 +334,7 @@ function cmdarg_parse
             fi
         fi
 
-        if [ ${CMDARG["${opt}"]+abc} ]; then
+        if [ -n "$opt" ] && [ ${CMDARG["${opt}"]+abc} ]; then
             cmdarg_set_opt "${CMDARG[$opt]}" "$optarg"
             local rc=$?
             failed=$((failed + $rc))