Function createCSS

core/cb.addons/require-tools/less/lessc.js:6336–6396

(styles, sheet, lastModified)

}

function createCSS(styles, sheet, lastModified) {
    // Strip the query-string
    var href = sheet.href || '';

    // If there is no title set, use the filename, minus the extension
    var id = 'less:' + (sheet.title || extractId(href));

    // If this has already been inserted into the DOM, we may need to replace it
    var oldCss = document.getElementById(id);
    var keepOldCss = false;

    // Create a new stylesheet node for insertion or (if necessary) replacement
    var css = document.createElement('style');
    css.setAttribute('type', 'text/css');
    if (sheet.media) {
        css.setAttribute('media', sheet.media);
    }
    css.id = id;

    if (css.styleSheet) { // IE
        try {
            css.styleSheet.cssText = styles;
        } catch (e) {
            throw new(Error)("Couldn't reassign styleSheet.cssText.");
        }
    } else {
        css.appendChild(document.createTextNode(styles));

        // If new contents match contents of oldCss, don't replace oldCss
        keepOldCss = (oldCss !== null && oldCss.childNodes.length > 0 && css.childNodes.length > 0 &&
            oldCss.firstChild.nodeValue === css.firstChild.nodeValue);
    }

    var head = document.getElementsByTagName('head')[0];

    // If there is no oldCss, just append; otherwise, only append if we need
    // to replace oldCss with an updated stylesheet
    if (oldCss === null || keepOldCss === false) {
        var nextEl = sheet && sheet.nextSibling || null;
        if (nextEl) {
            nextEl.parentNode.insertBefore(css, nextEl);
        } else {
            head.appendChild(css);
        }
    }
    if (oldCss && keepOldCss === false) {
        oldCss.parentNode.removeChild(oldCss);
    }

    // Don't update the local store if the file wasn't modified
    if (lastModified && cache) {
        log('saving ' + href + ' to cache.', logLevel.info);
        try {
            cache.setItem(href, styles);
            cache.setItem(href + ':timestamp', lastModified);
        } catch(e) {
            //TODO - could do with adding more robust error handling
            log('failed to save', logLevel.errors);