if-follow-package/docs/scripts/linenumber.js

if-follow-package is a JavaScript library that provides APIs for managing followers and followings on GitHub. This package allows you to find users who are not following you back, find users who are following you back, unfollow users who are not following

/*global document */
(() => {
    const source = document.getElementsByClassName('prettyprint source linenums');
    let i = 0;
    let lineNumber = 0;
    let lineId;
    let lines;
    let totalLines;
    let anchorHash;

    if (source && source[0]) {
        anchorHash = document.location.hash.substring(1);
        lines = source[0].getElementsByTagName('li');
        totalLines = lines.length;

        for (; i < totalLines; i++) {
            lineNumber++;
            lineId = `line${lineNumber}`;
            lines[i].id = lineId;
            if (lineId === anchorHash) {
                lines[i].className += ' selected';
            }
        }
    }
})();