Adding @flow to the top of Javascript multiple files

add_flow.sh

#!/bin/bash
# Based on http://stackoverflow.com/questions/151677/tool-for-adding-license-headers-to-source-files

for i in src/*.js src/*/*.js src/*/*/*.js src/*/*/*/*.js src/*/*/*/*/*.js
do
  if ! grep -q @flow $i
  then
    (echo -e $"/**\n * @format\n * @flow\n */\n") > flowificator
    cat flowificator $i >$i.new && mv $i.new $i
    rm flowificator
  fi
done

instruction.md

This shell script will add @format and @flow to the top of all .js files that are inside src folder. Keep this shell file at the root of your project

Make a file executable in Terminal on Mac

Shell scripts must be executable files in order to run. You can use the chmod command to indicate that the text file is executable.

1. In the Terminal app on your Mac. Enter the chmod command. For example:

chmod 755 YourScriptName.sh

2. After making the shell script file executable, you can run it by entering its pathname. For example:

./YourScriptName.sh