fix: add fallback for unbound variables in bash3

bin/install

@@ -41,16 +41,16 @@ nodebuild_wrapped() {
 
 install_canon_version() {
   local install_type="$1" version="$2" install_path="$3"
-  local nodebuild_args=()
+  local args=()
 
   if [ "$install_type" = ref ]; then
-    nodebuild_args+=(-c)
+    args+=(-c)
   fi
 
   try_to_update_nodebuild
 
   NODE_BUILD_BUILD_PATH="$ASDF_DOWNLOAD_PATH" NODE_BUILD_CACHE_PATH="$ASDF_DOWNLOAD_PATH" \
-    nodebuild_wrapped "${nodebuild_args[@]-}" "$version" "$install_path"
+    nodebuild_wrapped ${args+"${args[@]}"} "$version" "$install_path"
 }
 
 

lib/commands/command-nodebuild.bash

@@ -22,7 +22,7 @@ if [[ "${ASDF_NODEJS_CONCURRENCY-}" =~ ^[0-9]+$ ]]; then
 fi
 
 nodebuild="${ASDF_NODEJS_NODEBUILD:-$ASDF_NODEJS_NODEBUILD_HOME/bin/node-build}" 
-nodebuild_args=()
+args=()
 
 if ! [ -x "$nodebuild" ]; then
   printf "Binary for node-build not found\n"
@@ -35,7 +35,7 @@ if ! [ -x "$nodebuild" ]; then
 fi
 
 if [ "${ASDF_NODEJS_VERBOSE_INSTALL-}" ]; then
-  nodebuild_args+=(-v)
+  args+=(-v)
 fi
 
-exec "$nodebuild" "${nodebuild_args[@]-}" "$@"
+exec "$nodebuild" ${args+"${args[@]}"} "$@"