[REF] tools: rename extras into tools

tools/benchmarks/shared/utils.js

@@ -0,0 +1,49 @@
+//------------------------------------------------------------------------------
+// Generating demo data
+//------------------------------------------------------------------------------
+const AUTHORS = ["Aaron", "David", "Vincent"];
+const CONTENT = [
+  "Lorem ipsum dolor sit amet",
+  "Sed ut perspiciatis unde omnis iste natus error sit voluptatem",
+  "Excepteur sint occaecat cupidatat non proident"
+];
+
+function chooseRandomly(array) {
+  const index = Math.floor(Math.random() * array.length);
+  return array[index];
+}
+
+let nextId = 1;
+export function buildData(n = 1000) {
+  const data = [];
+  for (let i = 0; i < n; i++) {
+      let id = nextId++;
+    data.push({
+      id: id,
+      author: chooseRandomly(AUTHORS),
+      msg: `${id}: ${chooseRandomly(CONTENT)}`,
+      likes: 0
+    });
+  }
+  return data;
+}
+
+//------------------------------------------------------------------------------
+// Measuring helpers
+//------------------------------------------------------------------------------
+let startTime;
+let lastMeasure;
+export function startMeasure(descr) {
+  startTime = performance.now();
+  lastMeasure = descr;
+}
+export function stopMeasure() {
+  let last = lastMeasure;
+  if (lastMeasure) {
+    window.setTimeout(function() {
+      lastMeasure = null;
+      const stop = performance.now();
+      console.log(`[${last}] took  ${Number(stop - startTime).toFixed()}ms`);
+    }, 0);
+  }
+}