Set additional bash options and group together

install.sh

@@ -1,8 +1,15 @@
 #!/usr/bin/env bash
-set -o pipefail
+
+# Setup script environment
+set -o errexit  #Exit immediately if a pipeline returns a non-zero status
+set -o errtrace #Trap ERR from shell functions, command substitutions, and commands from subshell
+set -o nounset  #Treat unset variables as an error
+set -o pipefail #Pipe will exit with last non-zero status if applicable
 shopt -s expand_aliases
 alias die='EXIT=$? LINE=$LINENO error_exit'
 trap die ERR
+trap cleanup EXIT
+
 function error_exit() {
     REASON=$1
     MSG="\e[91mERROR: \e[93m$EXIT@"
@@ -19,7 +26,6 @@ function cleanup() {
     popd >/dev/null
     rm -rf $TMP
 }
-trap cleanup EXIT
 TMP=`mktemp -d`
 pushd $TMP >/dev/null