Find unused dependencies in the src directory (check for the presence of package name). Reads candidates from stdin or the file provided

find-used-deps.sh

#! /bin/bash

# Array of packages that must be kept although unused
must_keep_packages=('react-dom')

# Function to handle checking/printing if a package is unused and removable
function handle_package() {
	local package=$1
	# Skip this package is an important, must-keep package. 
	# Otherwise add it to the unused packages list
	if [[ ${must_keep_packages[@]} =~ $package ]]
	then
		: # No op
	else
		echo $package
	fi
}

# Driver loop
# Inspect unused packages
while read line
do
	grep $line -r src/ > /dev/null || handle_package $line
done < "${1:-/dev/stdin}"