ZuluPro/myblog

Prism.hooks.add('after-highlight', function (env) {
    // works only for <code> wrapped inside <pre data-line-numbers> (not inline)
    var pre = env.element.parentNode;
    if (!pre || !/pre/i.test(pre.nodeName) || pre.className.indexOf('line-numbers') === -1) {
        return;
    }

    var linesNum = (1 + env.code.split('\n').length);
    var lineNumbersWrapper;

    var lines = new Array(linesNum);
    lines = lines.join('<span></span>');

    lineNumbersWrapper = document.createElement('span');
    lineNumbersWrapper.className = 'line-numbers-rows';
    lineNumbersWrapper.innerHTML = lines;

    if (pre.hasAttribute('data-start')) {
        pre.style.counterReset = 'linenumber ' + (parseInt(pre.getAttribute('data-start'), 10) - 1);
    }

    env.element.appendChild(lineNumbersWrapper);

});