Add counter snippet

test/counter/counter.js

@@ -0,0 +1,12 @@
+const counter = (selector, start, end, step = 1, duration = 2000) => {
+let current = start,
+_step = (end - start) * step < 0 ? -step : step,
+timer = setInterval(() => {
+current += _step;
+document.querySelector(selector).innerHTML = current;
+if (current >= end) document.querySelector(selector).innerHTML = end;
+if (current >= end) clearInterval(timer);
+}, Math.abs(Math.floor(duration / (end - start))));
+return timer;
+};
+module.exports = counter;