benchmark

benchmark provides a standard way of writing and running benchmarks in Dart. Inspired by both benchmark_harness and test.

Writing Benchmarks.

Benchmarks are specified using the top-level benchmark() function:

import 'package:benchmark/benchmark.dart';

void main() {
  benchmark('List.generate(100k)', () {
    List.generate(100000, (i) => i);
  });
}

Benchmarks can be grouped together using the group() function. Each group's description is added to the beginning of its benchmark's descriptions:

import 'package:benchmark/benchmark.dart';

void main() {
  group('List', () {
    benchmark('.generate(100k)', () {
      List.generate(100000, (i) => i);
    });
  });

  group('Map', () {
    benchmark('.unmodifiable(other)', () {
      Map.unmodifiable({
        'value': 1
      });
    }, iterations: 100);
  });
}

Groups at the same level, with the same name, will be merged into one, allowing for different benchmark setups, without losing the overview in the output.

You can use the setUp() and tearDown() functions to share code between benchmarks. The setUp() callback will run before every benchmark in a group, and tearDown() will run after:

import 'package:benchmark/benchmark.dart';

void main() {
  List<int> list;

  setUp(() => list = List.generate(100000, (i) => i));

  tearDown(() => list = null);

  benchmark('List(100k).forEach()', () {
    list.forEach((i) {});
  });
}

You can use the setUpEach() and tearDownEach() functions to share code between iterations of benchmarks. The setUpEach() callback will run before every iteration in a benchmark, and tearDownEach() will run after:

import 'package:benchmark/benchmark.dart';

void main() {
  List<int> list;

  setUpEach(() => list = List.generate(100000, (i) => i));

  tearDownEach(() => list = null);

  benchmark('List(100k).map()', () {
    list.map((i) => '$i');
  });
}

Running benchmarks

benchmark comes with a simple executable to automatically run all your benchmarks:

pub run benchmark

See the --help flag for more information.