quick script to log packages that are registered in your package.json but not explicitly called in your code

unused-dependencies.js

/* eslint-disable */

/**
 * Approximately list packages that are
 * registered in your package json but
 * not used in your code
 *
 */


// === config start === //

// the files to read to determine actual
// used packages
var fileGlob = '{gulpfile.js,gulp/**/*.js}';

// the package.json keys to use to determine
// registered dependencies
var registeredIn = ['devDependencies'];

// any packages you would want to exclude
// from the final list
var excludePackages = [];

// package json
var packageJSON = require('./package.json');

// === config end === //


var readGlob = require('read-glob-promise');

function matchRequires(packages, content) {
	var matches = content.match(/require\(('|")[a-z0-9\-_\\/]+('|")\)/gi);
	return matches ? packages.concat(matches) : packages;
}

function unique(req, index, packages) {
	return packages.indexOf(req) === index;
}

function trimRequire(req) {
	return req.replace(/(require\()|('|")|\)/gi, '');
}

function alphabetically(a, b) {
	if (a < b) return -1;
	if (a > b) return 1;
	return 0;
}

function registeredDeps(pckgJson, keys) {
	return keys
		.reduce(function (packages, key) {
			return pckgJson[key]
				? packages.concat(Object.keys(pckgJson[key]))
				: packages;
		}, []);
}

function log(message) {
	return function (packages) {
		console.log('===>', packages.length, message, '\n', JSON.stringify(packages, null, 2));
		return packages;
	};
}

function exclude(excluded) {
	return function (pckg) {
		return 0 > excluded.indexOf(pckg);
	}
}

readGlob(fileGlob, 'utf8')
	.then(function (contents) {
		return contents
			.reduce(matchRequires, [])
			.filter(unique)
			.map(trimRequire)
			.sort(alphabetically);
	})
	.then(log('used packages:'))
	.then(function (usedPackages) {
		return registeredDeps(packageJSON, registeredIn)
			.filter(exclude(usedPackages))
			.filter(exclude(excludePackages));
	})
	.then(log('registered but not explicitly used packages:'))
	.catch(function (err) {
		console.error(err);
	});

just add to project root and run npm i read-glob-promise then customize the config part of the script and then run node unused-dependencies.
you should see the output in your console