looping array inside shell script with a different user using HEREDOC doesnt work

Question

I want to perform the set of actions inside a different user while running my script, so i am using HEREDOC to perform such actions, but no matter alternatives i try, i cannot able to reference my values in loop inside the HEREDOC.

In this case it prints the first line and exits.

#!/bin/bash
func () {
test=("$@")
sudo su - someuser <<- EOF
    echo "${test[*]}"
    for i in "${test[@]}" ; do
        echo "$i"
    done
EOF
}
arrVar=("AC" "TV" "Mobile" "Fridge" "Oven" "Blender")
arrVar+=("hello.   why would it fail now      with spaces then")
func "$arrVar"  ###### Tried this as well "${arrVar[@]}"

prints the output as like this:

[root@ip-10-9-1-1 ~]# ./test.sh
AC

it works fine just fine if i remove the HEREDOC and run as currentUser, but i need to run this as Different User.

EDIT: @roaima answer looks to be promising , but i had to access lot of outside variables, hence passing them as below wouldn't scale well enough for me.

sudo -u someuser bash -c ' ' -- "lot" "of" "variables" "$@"

so i came to this question in the first place using arrays over strings because of the IFS being not respected inside HEREDOC, perhaps i will get better answer if i post my original issue.

so here it it is:

cp="/usr/bin/cp"
rm="/usr/bin/rm"
mv="/usr/bin/mv"
exec_operations () {
echo "Executing operations: $@"
operations=$@
date=$(date +%Y-%m-%d-%H-%M-%S)
sudo su - someuser <<- EOF
IFS=";"
for operation in $operations ; do
    echo "Performing the following $operation with $cp, $rm & $mv"
done
unset IFS

EOF
}
text="cp /tmp/text.txt something/;cp /tmp/text2.txt something/;"
exec_operations "$text"

Answer 1

Your invocation func "$arrVar" passes in a string rather than an array. The string happens to correspond to the first element of the array, which is why you see just the first value in your loop (there is only one value).

Use this instead

func "${arrVar[@]}"

You also need to be aware that the unquoted heredoc symbol EOF means that the enclosure is treated as being in double quotes. This in turn means that any reference to a variable such as $i will be evaluated as part of the heredoc, and not as part of its execution. Double quotes will be handled also as part of the expansion, not the execution. Your sudo su (ugh) construct will therefore see something like this:

echo 'AC TV Mobile Fridge Oven Blender hello.   why would it fail now      with spaces then'
for i in 'AC TV Mobile Fridge Oven Blender hello.   why would it fail now      with spaces then' ; do
    echo ''
done

Something like this should work for you instead. I've extended your example to respond to your revised question asking how to pass in extra variables:

#!/bin/bash
func () {
    sudo -u someuser bash -c '
        date=$1; shift
        test=("$@")
        echo "${test[*]}"
        for i in "${test[@]}"
        do
            echo "$date: $i"
        done
    ' -- "$@"
}
arrVar=("AC" "TV" "Mobile" "Fridge" "Oven" "Blender")
arrVar+=("hello.   why would it fail now      with spaces then")
date=$(date --utc +'%Y-%m-%d %H:%M')
func "$date" "${arrVar[@]}"