Bash Script using a function to test to make sure commands are available. Allows to test for multiple versions of a command

command_chech.sh

#!/usr/bin/env bash

cmd_list=(
  "virtualenv-2.7 virtualenv-2.5 virtualenv"
  "docker docker.io"
)

# Function to check if referenced command exists
cmd_exists() {
  if [ $# -eq 0 ]; then
    echo 'WARNING: No command argument was passed to verify exists'
  fi

  #cmds=($(echo "${1}"))
  cmds=($(printf '%s' "${1}"))
  fail_counter=0
  for cmd in "${cmds[@]}"; do
    command -v "${cmd}" >&/dev/null # portable 'which'
    rc=$?
    if [ "${rc}" != "0" ]; then
      fail_counter=$((fail_counter+1))
    fi
  done

  if [ "${fail_counter}" -ge "${#cmds[@]}" ]; then
    echo "Unable to find one of the required commands [${cmds[*]}] in your PATH"
    return 1
  fi
}

# Verify that referenced commands exist on the system
for cmd in "${cmd_list[@]}"; do
  cmd_exists "${cmd[@]}"
  # shellcheck disable=SC2181
  if [ $? -ne 0 ]; then
    return $?
  fi
done