test/list_path_observer_test.dart

// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'dart:async';
import 'package:observable/observable.dart';
import 'package:observe/observe.dart';
import 'observe_test_utils.dart';

import 'package:observe/mirrors_used.dart' as mu; // make test smaller.
import 'package:smoke/mirrors.dart';

/// Uses [mu].
main() {
  useMirrors();
  dirtyCheckZone().run(_runTests);
}

_runTests() {
  var list;
  var obs;
  var o1, o2;
  var sub;
  int changes;

  setUp(() {
    list = toObservable([
      o1 = new TestModel()..a = (new TestModel()..b = 1),
      o2 = new TestModel()..a = (new TestModel()..b = 2),
      new TestModel()..a = (new TestModel()..b = 3)
    ]);
    obs = new ListPathObserver(list, 'a.b');
    changes = 0;
    sub = obs.changes.listen((e) {
      changes++;
    });
  });

  tearDown(() {
    sub.cancel();
    list = obs = o1 = o2 = null;
  });

  test('list path observer noticed length changes', () {
    expect(o2.a.b, 2);
    expect(list[1].a.b, 2);
    return _nextMicrotask(null)
        .then((_) {
          expect(changes, 0);
          list.removeAt(1);
        })
        .then(_nextMicrotask)
        .then((_) {
          expect(changes, 1);
          expect(list[1].a.b, 3);
        });
  });

  test('list path observer delivers deep change', () {
    expect(o2.a.b, 2);
    expect(list[1].a.b, 2);
    int changes = 0;
    obs.changes.listen((e) {
      changes++;
    });
    return _nextMicrotask(null)
        .then((_) {
          expect(changes, 0);
          o2.a.b = 4;
        })
        .then(_nextMicrotask)
        .then((_) {
          expect(changes, 1);
          expect(list[1].a.b, 4);
          o1.a = new TestModel()..b = 5;
        })
        .then(_nextMicrotask)
        .then((_) {
          expect(changes, 2);
          expect(list[0].a.b, 5);
        });
  });
}

_nextMicrotask(_) => new Future(() {});

@reflectable
class TestModel extends PropertyChangeNotifier {
  var _a, _b;
  TestModel();

  get a => _a;
  void set a(newValue) {
    _a = notifyPropertyChange(#a, _a, newValue);
  }

  get b => _b;
  void set b(newValue) {
    _b = notifyPropertyChange(#b, _b, newValue);
  }
}