only-changed-jest-watch-plugin/example/node_modules/detect-newline/index.js

Jest watch plugin for running either only the modified test (for TDD), or tests of dependant modules

'use strict';
module.exports = function (str) {
	if (typeof str !== 'string') {
		throw new TypeError('Expected a string');
	}

	var newlines = (str.match(/(?:\r?\n)/g) || []);

	if (newlines.length === 0) {
		return null;
	}

	var crlf = newlines.filter(function (el) {
		return el === '\r\n';
	}).length;

	var lf = newlines.length - crlf;

	return crlf > lf ? '\r\n' : '\n';
};

module.exports.graceful = function (str) {
	return module.exports(str) || '\n';
};