Adding an inheriting data model to Node

tests/html/node_model_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.
+
+library node_model_test;
+import 'dart:async';
+import 'dart:html';
+import '../../pkg/unittest/lib/unittest.dart';
+import '../../pkg/unittest/lib/html_config.dart';
+
+Future get nextStep {
+  return new Future.delayed(new Duration());
+}
+
+class ModelTracker {
+  Element element = new DivElement();
+  List models = [];
+
+  ModelTracker() {
+    element.onModelChanged.listen((node) {
+      models.add(node.model);
+    });
+  }
+
+  void append(ModelTracker other) {
+    element.append(other.element);
+  }
+
+  get model => element.model;
+  void set model(value) {
+    element.model = value;
+  }
+
+  void clearModel() {
+    element.clearModel();
+  }
+}
+
+main() {
+  useHtmlConfiguration();
+
+  test('basic top down', () {
+    var a = new DivElement();
+    var b = new SpanElement();
+    var c = new DivElement();
+    var d = new DivElement();
+    var e = new DivElement();
+    var model = {};
+    var model2 = {};
+    var model3 = {};
+
+    document.body.append(a);
+    a.append(b);
+
+    a.model = model;
+    expect(a.model, model);
+    expect(b.model, model);
+
+    b.append(c);
+
+    return nextStep.then((_) {
+      expect(c.model, model);
+
+      d.append(e);
+      c.append(d);
+
+      return nextStep;
+    }).then((_) {
+      expect(e.model, model);
+
+      b.remove();
+      return nextStep;
+    }).then((_) {
+      expect(b.model, isNull);
+      expect(e.model, isNull);
+
+      return nextStep;
+    }).then((_) {
+      a.append(b);
+      a.model = model2;
+
+      return nextStep;
+    }).then((_) {
+      expect(e.model, model2);
+
+      c.model = model3;
+      expect(c.model, model3);
+      expect(b.model, model2);
+      expect(e.model, model3);
+
+      return nextStep;
+    }).then((_) {
+      d.remove();
+      c.append(d);
+
+      return nextStep;
+    }).then((_) {
+      expect(d.model, model3);
+
+      c.clearModel();
+      expect(d.model, model2);
+    });
+  });
+
+  test('changes', () {
+    var a = new ModelTracker();
+    var b = new ModelTracker();
+    var c = new ModelTracker();
+    var d = new ModelTracker();
+
+    var model = {};
+    var cModel = {};
+
+    document.body.append(a.element);
+
+    a.append(b);
+
+    return nextStep.then((_) {
+      expect(a.models, []);
+      expect(b.models.length, 0);
+
+      a.model = model;
+
+      expect(a.models, [model]);
+      expect(b.models, [model]);
+
+      b.append(c);
+      return nextStep;
+    }).then((_) {
+      expect(c.models, [model]);
+
+      c.append(d);
+      return nextStep;
+    }).then((_) {
+      c.model = cModel;
+      expect(b.models, [model]);
+      expect(c.models, [model, cModel]);
+      expect(d.models, [model, cModel]);
+
+      c.clearModel();
+      expect(c.models, [model, cModel, model]);
+      expect(d.models, [model, cModel, model]);
+    });
+  });
+
+  test('bottom up', () {
+    var a = new ModelTracker();
+    var b = new ModelTracker();
+    var c = new ModelTracker();
+    var d = new ModelTracker();
+
+    var aModel = {};
+    var cModel = {};
+
+    c.append(d);
+    c.model = cModel;
+    b.append(c);
+    a.append(b);
+    a.model = aModel;
+    document.body.append(a.element);
+
+    return nextStep.then((_) {
+      expect(a.models, [aModel]);
+      expect(b.models, [aModel]);
+      expect(c.models, [cModel]);
+      expect(d.models, [cModel]);
+    });
+  });
+}