#!/bin/bash
#
# make sure indirect expansion for arrays uses the closest-scope instance
# of the resulting variable name

array_1=("PASS")
array_2=("1 foo" "2 foo")

unsafe_fn ()
{
    local array_1=('HELLO')
    local a=("${!1}") b=("${!2}")
    printf '%s;' "${a[@]}" "${b[@]}"
    printf '\n'
}

safe_fn ()
{
    local a=("${!1}") b=("${!2}")
    local array_1=('FAIL')
    printf '%s;' "${a[@]}" "${b[@]}"
    printf '\n'
}

unsafe_fn 'array_1[@]' 'array_2[@]'
safe_fn 'array_1[@]' 'array_2[@]'

echo after: ${array_1[@]}