pkg/observe/test/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 'package:observe/observe.dart';
import 'package:unittest/unittest.dart';
import 'observe_test_utils.dart';

// This file contains code ported from:
// https://github.com/rafaelw/ChangeSummary/blob/master/tests/test.js

main() {
  group('PathObserver', observePathTests);
}

observePath(obj, path) => new PathObserver(obj, path);

observePathTests() {
  observeTest('Degenerate Values', () {
    expect(observePath(null, '').value, null);
    expect(observePath(123, '').value, 123);
    expect(observePath(123, 'foo.bar.baz').value, null);

    // shouldn't throw:
    observePath(123, '').changes.listen((_) {}).cancel();
    observePath(null, '').value = null;
    observePath(123, '').value = 42;
    observePath(123, 'foo.bar.baz').value = 42;

    var foo = {};
    expect(observePath(foo, '').value, foo);

    foo = new Object();
    expect(observePath(foo, '').value, foo);

    expect(observePath(foo, 'a/3!').value, null);
  });

  observeTest('get value at path ObservableBox', () {
    var obj = new ObservableBox(new ObservableBox(new ObservableBox(1)));

    expect(observePath(obj, '').value, obj);
    expect(observePath(obj, 'value').value, obj.value);
    expect(observePath(obj, 'value.value').value, obj.value.value);
    expect(observePath(obj, 'value.value.value').value, 1);

    obj.value.value.value = 2;
    expect(observePath(obj, 'value.value.value').value, 2);

    obj.value.value = new ObservableBox(3);
    expect(observePath(obj, 'value.value.value').value, 3);

    obj.value = new ObservableBox(4);
    expect(observePath(obj, 'value.value.value').value, null);
    expect(observePath(obj, 'value.value').value, 4);
  });


  observeTest('get value at path ObservableMap', () {
    var obj = toObservable({'a': {'b': {'c': 1}}});

    expect(observePath(obj, '').value, obj);
    expect(observePath(obj, 'a').value, obj['a']);
    expect(observePath(obj, 'a.b').value, obj['a']['b']);
    expect(observePath(obj, 'a.b.c').value, 1);

    obj['a']['b']['c'] = 2;
    expect(observePath(obj, 'a.b.c').value, 2);

    obj['a']['b'] = toObservable({'c': 3});
    expect(observePath(obj, 'a.b.c').value, 3);

    obj['a'] = toObservable({'b': 4});
    expect(observePath(obj, 'a.b.c').value, null);
    expect(observePath(obj, 'a.b').value, 4);
  });

  observeTest('set value at path', () {
    var obj = toObservable({});
    observePath(obj, 'foo').value = 3;
    expect(obj['foo'], 3);

    var bar = toObservable({ 'baz': 3 });
    observePath(obj, 'bar').value = bar;
    expect(obj['bar'], bar);

    observePath(obj, 'bar.baz.bat').value = 'not here';
    expect(observePath(obj, 'bar.baz.bat').value, null);
  });

  observeTest('set value back to same', () {
    var obj = toObservable({});
    var path = observePath(obj, 'foo');
    var values = [];
    path.changes.listen((_) { values.add(path.value); });

    path.value = 3;
    expect(obj['foo'], 3);
    expect(path.value, 3);

    observePath(obj, 'foo').value = 2;
    performMicrotaskCheckpoint();
    expect(path.value, 2);
    expect(observePath(obj, 'foo').value, 2);

    observePath(obj, 'foo').value = 3;
    performMicrotaskCheckpoint();
    expect(path.value, 3);

    performMicrotaskCheckpoint();
    expect(values, [2, 3]);
  });

  observeTest('Observe and Unobserve - Paths', () {
    var arr = toObservable({});

    arr['foo'] = 'bar';
    var fooValues = [];
    var fooPath = observePath(arr, 'foo');
    var fooSub = fooPath.changes.listen((_) {
      fooValues.add(fooPath.value);
    });
    arr['foo'] = 'baz';
    arr['bat'] = 'bag';
    var batValues = [];
    var batPath = observePath(arr, 'bat');
    var batSub = batPath.changes.listen((_) {
      batValues.add(batPath.value);
    });

    performMicrotaskCheckpoint();
    expect(fooValues, ['baz']);
    expect(batValues, []);

    arr['foo'] = 'bar';
    fooSub.cancel();
    arr['bat'] = 'boo';
    batSub.cancel();
    arr['bat'] = 'boot';

    performMicrotaskCheckpoint();
    expect(fooValues, ['baz']);
    expect(batValues, []);
  });

  observeTest('Path Value With Indices', () {
    var model = toObservable([]);
    var path = observePath(model, '0');
    path.changes.listen(expectAsync1((_) {
      expect(path.value, 123);
    }));
    model.add(123);
  });

  group('ObservableList', () {
    observeTest('isNotEmpty', () {
      var model = new ObservableList();
      var path = observePath(model, 'isNotEmpty');
      expect(path.value, false);

      var future = path.changes.first.then((_) {
        expect(path.value, true);
      });
      model.add(123);

      return future;
    });

    observeTest('isEmpty', () {
      var model = new ObservableList();
      var path = observePath(model, 'isEmpty');
      expect(path.value, true);

      var future = path.changes.first.then((_) {
        expect(path.value, false);
      });
      model.add(123);

      return future;
    });
  });

  for (var createModel in [() => new TestModel(), () => new WatcherModel()]) {
    observeTest('Path Observation - ${createModel().runtimeType}', () {
      var model = createModel()..a =
          (createModel()..b = (createModel()..c = 'hello, world'));

      var path = observePath(model, 'a.b.c');
      var lastValue = null;
      var sub = path.changes.listen((_) { lastValue = path.value; });

      model.a.b.c = 'hello, mom';

      expect(lastValue, null);
      performMicrotaskCheckpoint();
      expect(lastValue, 'hello, mom');

      model.a.b = createModel()..c = 'hello, dad';
      performMicrotaskCheckpoint();
      expect(lastValue, 'hello, dad');

      model.a = createModel()..b =
          (createModel()..c = 'hello, you');
      performMicrotaskCheckpoint();
      expect(lastValue, 'hello, you');

      model.a.b = 1;
      performMicrotaskCheckpoint();
      expect(lastValue, null);

      // Stop observing
      sub.cancel();

      model.a.b = createModel()..c = 'hello, back again -- but not observing';
      performMicrotaskCheckpoint();
      expect(lastValue, null);

      // Resume observing
      sub = path.changes.listen((_) { lastValue = path.value; });

      model.a.b.c = 'hello. Back for reals';
      performMicrotaskCheckpoint();
      expect(lastValue, 'hello. Back for reals');
    });
  }

  observeTest('observe map', () {
    var model = toObservable({'a': 1});
    var path = observePath(model, 'a');

    var values = [path.value];
    var sub = path.changes.listen((_) { values.add(path.value); });
    expect(values, [1]);

    model['a'] = 2;
    performMicrotaskCheckpoint();
    expect(values, [1, 2]);

    sub.cancel();
    model['a'] = 3;
    performMicrotaskCheckpoint();
    expect(values, [1, 2]);
  });

  observeTest('errors thrown from getter/setter', () {
    var model = new ObjectWithErrors();
    var observer = new PathObserver(model, 'foo');

    expect(() => observer.value, throws);
    expect(model.getFooCalled, 1);

    expect(() { observer.value = 123; }, throws);
    expect(model.setFooCalled, [123]);
  });

  observeTest('object with noSuchMethod', () {
    var model = new NoSuchMethodModel();
    var observer = new PathObserver(model, 'foo');

    expect(observer.value, 42);
    observer.value = 'hi';
    expect(model._foo, 'hi');
    expect(observer.value, 'hi');

    expect(model.log, [#foo, const Symbol('foo='), #foo]);

    // These shouldn't throw
    observer = new PathObserver(model, 'bar');
    expect(observer.value, null, reason: 'path not found');
    observer.value = 42;
    expect(observer.value, null, reason: 'path not found');
  });

  observeTest('object with indexer', () {
    var model = new IndexerModel();
    var observer = new PathObserver(model, 'foo');

    expect(observer.value, 42);
    expect(model.log, ['[] foo']);
    model.log.clear();

    observer.value = 'hi';
    expect(model.log, ['[]= foo hi']);
    expect(model._foo, 'hi');

    expect(observer.value, 'hi');

    // These shouldn't throw
    model.log.clear();
    observer = new PathObserver(model, 'bar');
    expect(observer.value, null, reason: 'path not found');
    expect(model.log, ['[] bar']);
    model.log.clear();

    observer.value = 42;
    expect(model.log, ['[]= bar 42']);
    model.log.clear();
  });
}

class ObjectWithErrors {
  int getFooCalled = 0;
  List setFooCalled = [];
  @reflectable get foo {
    getFooCalled++;
    (this as dynamic).bar;
  }
  @reflectable set foo(value) {
    setFooCalled.add(value);
    (this as dynamic).bar = value;
  }
}

class NoSuchMethodModel {
  var _foo = 42;
  List log = [];

  // TODO(ahe): Remove @reflectable from here (once either of
  // http://dartbug.com/15408 or http://dartbug.com/15409 are fixed).
  @reflectable noSuchMethod(Invocation invocation) {
    final name = invocation.memberName;
    log.add(name);
    if (name == #foo && invocation.isGetter) return _foo;
    if (name == const Symbol('foo=')) {
      _foo = invocation.positionalArguments[0];
      return null;
    }
    return super.noSuchMethod(invocation);
  }
}

class IndexerModel {
  var _foo = 42;
  List log = [];

  operator [](index) {
    log.add('[] $index');
    if (index == 'foo') return _foo;
  }

  operator []=(index, value) {
    log.add('[]= $index $value');
    if (index == 'foo') _foo = value;
  }
}

@reflectable
class TestModel extends ChangeNotifier {
  var _a, _b, _c;

  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);
  }

  get c => _c;

  void set c(newValue) {
    _c = notifyPropertyChange(#c, _c, newValue);
  }
}

class WatcherModel extends Observable {
  // TODO(jmesserly): dart2js does not let these be on the same line:
  // @observable var a, b, c;
  @observable var a;
  @observable var b;
  @observable var c;

  WatcherModel();
}