49cd69511d14d041a2504f60d5775b8febcd8274 - clock

commit	49cd69511d14d041a2504f60d5775b8febcd8274	[log] [tgz]
author	Devon Carew <devoncarew@google.com>	Wed Jun 15 13:34:09 2022 -0700
committer	GitHub <noreply@github.com>	Wed Jun 15 13:34:09 2022 -0700
tree	43605a6a217632b01658220f76ebb4829dd58818
parent	a75eb69c8e939e2e7eab70e4728da3bcf004e717 [diff]
parent	a73ef13c5be333c823a9a06d9faccac55ed4a8b9 [diff]

tree: 43605a6a217632b01658220f76ebb4829dd58818

README.md

This package provides a Clock class which encapsulates the notion of the “current time” and provides easy access to points relative to the current time. Different Clocks can have a different notion of the current time, and the default top-level clock's notion can be swapped out to reliably test timing-dependent code.

For example, you can use clock in your libraries like this:

// run_with_timing.dart
import 'package:clock/clock.dart';

/// Runs [callback] and prints how long it took.
T runWithTiming<T>(T Function() callback) {
  var stopwatch = clock.stopwatch()..start();
  var result = callback();
  print('It took ${stopwatch.elapsed}!');
  return result;
}

...and then test your code using the fake_async package, which automatically overrides the current clock:

// run_with_timing_test.dart
import 'run_with_timing.dart';

import 'package:fake_async/fake_async.dart';
import 'package:test/test.dart';

void main() {
  test('runWithTiming() prints the elapsed time', () {
    FakeAsync().run((async) {
      expect(() {
        runWithTiming(() {
          async.elapse(Duration(seconds: 10));
        });
      }, prints('It took 0:00:10.000000!'));
    });
  });
}