Performance tests for iterators.

test/js-perf-test/Iterators/forof.js

+// Copyright 2014 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+new BenchmarkSuite('ForOf', [1000], [
+  new Benchmark('ArrayValues', false, false, 0, ForOf, ForOfArraySetup, ForOfTearDown),
+  new Benchmark('ArrayKeys', false, false, 0, ForOf, ForOfArrayKeysSetup, ForOfTearDown),
+  new Benchmark('ArrayEntries', false, false, 0, ForOf, ForOfArrayEntriesSetup, ForOfTearDown),
+  new Benchmark('Uint8Array', false, false, 0, ForOf, ForOfUint8ArraySetup, ForOfTearDown),
+  new Benchmark('Float64Array', false, false, 0, ForOf, ForOfFloat64ArraySetup, ForOfTearDown),
+  new Benchmark('String', false, false, 0, ForOf, ForOfStringSetup, ForOfTearDown),
+]);
+
+
+var iterable;
+var N = 100;
+var expected, result;
+
+
+function ForOfArraySetupHelper(constructor) {
+  iterable = new constructor(N);
+  for (var i = 0; i < N; i++) iterable[i] = i;
+  expected = N - 1;
+}
+
+
+function ForOfArraySetup() {
+  ForOfArraySetupHelper(Array);
+  // Default iterator is values().
+}
+
+
+function ForOfArrayKeysSetup() {
+  ForOfArraySetupHelper(Array);
+  iterable = iterable.keys();
+}
+
+
+function ForOfArrayEntriesSetup() {
+  ForOfArraySetupHelper(Array);
+  iterable = iterable.entries();
+  expected = [N-1, N-1];
+}
+
+
+function ForOfUint8ArraySetup() {
+  ForOfArraySetupHelper(Uint8Array);
+}
+
+
+function ForOfFloat64ArraySetup() {
+  ForOfArraySetupHelper(Float64Array);
+}
+
+
+function ForOfStringSetup() {
+  iterable = "abcdefhijklmnopqrstuvwxyzABCDEFHIJKLMNOPQRSTUVWXYZ0123456789";
+  expected = "9";
+}
+
+
+function Equals(expected, actual) {
+  if (expected === actual) return true;
+  if (typeof expected !== typeof actual) return false;
+  if (typeof expected !== 'object') return false;
+  for (var k of Object.keys(expected)) {
+    if (!(k in actual)) return false;
+    if (!Equals(expected[k], actual[k])) return false;
+  }
+  for (var k of Object.keys(actual)) {
+    if (!(k in expected)) return false;
+  }
+  return true;
+}
+
+function ForOfTearDown() {
+  iterable = null;
+  if (!Equals(expected, result)) {
+    throw new Error("Bad result: " + result);
+  }
+}
+
+
+function ForOf() {
+  for (var x of iterable) {
+    result = x;
+  }
+}