feat(scripts): benchmarks (#2631)

scripts/benchmarks

@@ -0,0 +1,51 @@
+#!/usr/bin/env node
+
+require('@babel/register')
+
+const pkg = require('../package.json')
+const Benchmark = require('benchmark')
+const globby = require('globby')
+const resolve = require('path').resolve
+
+// ===================================================================
+
+function bench (path) {
+  let fn = require(resolve(path))
+  if (typeof fn !== 'function') {
+    fn = fn.default
+  }
+
+  const benchmarks = []
+  function benchmark (name, fn) {
+    benchmarks.push(new Benchmark(name, fn))
+  }
+
+  fn({
+    benchmark: benchmark,
+  })
+
+  benchmarks.forEach(function (benchmark) {
+    console.log(String(benchmark.run()))
+  })
+}
+
+function main () {
+  return globby(
+    pkg.workspaces.map(workspace =>
+      resolve(__dirname, '..', workspace, 'src/**/*.bench.js')
+    )
+  ).then(function (paths) {
+    if (!paths.length) {
+      throw new Error('no files to run')
+    }
+
+    for (let i = 0, n = paths.length; i < n; ++i) {
+      bench(paths[i])
+    }
+  })
+}
+new Promise(function (resolve) {
+  resolve(main())
+}).catch(function (error) {
+  console.log((error != null && (error.stack || error.message)) || error)
+})