Edit an apps shared preference entire file from a bash script (using run-as & sed)

edit-pref-file.sh

#!/usr/bin/env bash

# IMPORTANT:
# make sure to edit the variables below to make the script work for you and your app

package="my.package.com"
filename="sharedprefs.xml"

line=$(adb exec-out run-as "$package" cat "/data/data/$package/shared_prefs/$filename")
echo "$line" > /tmp/editpreffile.txt
$EDITOR /tmp/editpreffile.txt
newval=$(cat /tmp/editpreffile.txt)
echo "-${newval}-"
adb exec-out run-as "$package" sed -Ei -e "1s/.*/____/g" -e "/^_/!d" -e "s|____|${newval}|g" "/data/data/$package/shared_prefs/$filename"