performance.now for https://github.com/rrweb-io/rrweb/pull/464

gistfile1.txt

var xxxtime = 0;
var xxxcount = 0;
var yyytime = 0;
var yyycount = 0;

var rrwebRecord = (function () {

[...snip...]

                        if (m.attributeName === 'style') {
                            /// yyycount, yyytime, xxxcount, xxxtime are globals initialised to zero at top of file
                            yyycount += 1;
                            yyytime -= performance.now();
                            var old = _this.doc.createElement('span');
                            old.setAttribute('style', m.oldValue);
                            if (item.attributes['style'] === undefined) {
                                item.attributes['style'] = {};
                            }
                            for (var i = 0; i < target.style.length; i++) {
                                var pname = target.style[i];
                                var newValue = target.style.getPropertyValue(pname);
                                var newPriority = target.style.getPropertyPriority(pname);
                                if (newValue != old.style.getPropertyValue(pname) ||
                                    newPriority != old.style.getPropertyPriority(pname)) {
                                    if (newPriority == '') {
                                        item.attributes['style'][pname] = newValue;
                                    }
                                    else {
                                        item.attributes['style'][pname] = [newValue, newPriority];
                                    }
                                }
                            }
                            for (var i = 0; i < old.style.length; i++) {
                                var pname = old.style[i];
                                if (target.style.getPropertyValue(pname) === '' ||
                                    !target.style.getPropertyValue(pname)) {
                                    item.attributes['style'][pname] = false;
                                }
                            }
                            yyytime += performance.now();
                            console.log('YYY', yyytime / yyycount, yyytime, yyycount);

                            xxxcount += 1;
                            xxxtime -= performance.now();
                            item.attributes[m.attributeName+'xxx'] = transformAttribute(_this.doc, m.target.tagName, m.attributeName, value);
                            xxxtime += performance.now();
                            console.log('XXX', xxxtime / xxxcount, xxxtime, xxxcount);
                            console.log('Slower', yyytime / xxxtime);
                        }