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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import '../common.dart';
const int _kNumIterations = 1000;
const int _kNumWarmUp = 100;
void main() {
assert(false, "Don't run benchmarks in debug mode! Use 'flutter run --release'.");
// Warm up lap
for (int i = 0; i < _kNumWarmUp; i += 1) {
sumIterable(generateIterableSyncStar());
sumIterable(generateIterableList());
sumIterable(Iterable<int>.generate(100, generate));
}
final Stopwatch watch = Stopwatch();
watch.start();
for (int i = 0; i < _kNumIterations; i += 1) {
sumIterable(generateIterableSyncStar());
}
final int traverseIterableSyncStar = watch.elapsedMicroseconds;
watch
..reset()
..start();
for (int i = 0; i < _kNumIterations; i += 1) {
sumIterable(generateIterableList());
}
final int traverseIterableList = watch.elapsedMicroseconds;
watch
..reset()
..start();
for (int i = 0; i < _kNumIterations; i += 1) {
sumIterable(Iterable<int>.generate(100, generate));
}
final int traverseIterableGenerated = watch.elapsedMicroseconds;
watch
..reset()
..start();
final BenchmarkResultPrinter printer = BenchmarkResultPrinter();
const double scale = 1000.0 / _kNumIterations;
printer.addResult(
description: 'traverseIterableSyncStar',
value: traverseIterableSyncStar * scale,
unit: 'ns per iteration',
name: 'traverseIterableSyncStar_iteration',
);
printer.addResult(
description: 'traverseIterableList',
value: traverseIterableList * scale,
unit: 'ns per iteration',
name: 'traverseIterableList_iteration',
);
printer.addResult(
description: 'traverseIterableGenerated',
value: traverseIterableGenerated * scale,
unit: 'ns per iteration',
name: 'traverseIterableGenerated_iteration',
);
printer.printToStdout();
}
int generate(int index) => index;
// Generate an Iterable using a sync* method.
Iterable<int> generateIterableSyncStar() sync* {
for (int i = 0; i < 100; i++) {
yield i;
}
}
// Generate an Iterable using a List.
Iterable<int> generateIterableList() {
final List<int> items = <int>[];
for (int i = 0; i < 100; i++) {
items.add(i);
}
return items;
}
int sumIterable(Iterable<int> values) {
int result = 0;
for (final int value in values) {
result += value;
}
return result;
}