port polymer data binding tests

pkg/polymer/test/unbind_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 polymer.test.unbind_test;
+
+import 'dart:async' show Future;
+import 'dart:html';
+
+@MirrorsUsed(targets: const [Polymer], override: 'polymer.test.unbind_test')
+import 'dart:mirrors' show reflect, reflectClass, MirrorSystem, MirrorsUsed;
+
+import 'package:polymer/polymer.dart';
+import 'package:polymer/platform.dart' as Platform;
+import 'package:unittest/unittest.dart';
+import 'package:unittest/html_config.dart';
+
+@CustomTag('x-test')
+class XTest extends PolymerElement {
+  @observable var foo = '';
+  @observable var bar;
+
+  bool forceReady = true;
+  bool fooWasChanged = false;
+  var validBar;
+
+  factory XTest() => new Element.tag('x-test');
+  XTest.created() : super.created();
+
+  ready() {}
+
+  fooChanged() {
+    fooWasChanged = true;
+  }
+
+  barChanged() {
+    validBar = bar;
+  }
+
+  bool get isBarValid => validBar == bar;
+}
+
+main() {
+  initPolymer();
+  useHtmlConfiguration();
+
+  setUp(() => Polymer.onReady);
+
+  test('unbind', unbindTests);
+}
+
+Future testAsync(List<Function> tests, int delayMs, [List args]) {
+  if (tests.length == 0) return new Future.value();
+  // TODO(jmesserly): CustomElements.takeRecords();
+  return new Future.delayed(new Duration(milliseconds: delayMs), () {
+    if (args == null) args = [];
+    var lastArgs = Function.apply(tests.removeAt(0), args);
+    return testAsync(tests, delayMs, lastArgs);
+  });
+}
+
+// TODO(sorvell): In IE, the unbind time is indeterminate, so wait an
+// extra beat.
+delay(x) => new Future.delayed(new Duration(milliseconds: 50), () => x);
+
+// TODO(jmesserly): fix this when it's easier to get a private symbol.
+final unboundSymbol = reflectClass(Polymer).variables.keys
+    .firstWhere((s) => MirrorSystem.getName(s) == '_unbound');
+
+_unbound(node) => reflect(node).getField(unboundSymbol).reflectee;
+
+unbindTests() {
+  var xTest = document.query('x-test');
+  xTest.foo = 'bar';
+  Platform.flush();
+
+  return delay(null).then((_) {
+    expect(_unbound(xTest), null, reason:
+        'element is bound when inserted');
+    expect(xTest.fooWasChanged, true, reason:
+        'element is actually bound');
+    xTest.remove();
+  }).then(delay).then((_) {
+    expect(_unbound(xTest), true, reason:
+        'element is unbound when removed');
+    return new XTest();
+  }).then(delay).then((node) {
+    expect(_unbound(node), null, reason:
+        'element is bound when not inserted');
+    node.foo = 'bar';
+    Platform.flush();
+    return node;
+  }).then(delay).then((node) {
+    expect(node.fooWasChanged, true, reason: 'node is actually bound');
+    var n = new XTest();
+    n.cancelUnbindAll();
+    return n;
+  }).then(delay).then((node) {
+    expect(_unbound(node), null, reason:
+        'element is bound when cancelUnbindAll is called');
+    node.unbindAll();
+    expect(_unbound(node), true, reason:
+        'element is unbound when unbindAll is called');
+    var n = new XTest()..id = 'foobar!!!';
+    document.body.append(n);
+    return n;
+  }).then(delay).then((node) {
+    expect(_unbound(node), null, reason:
+        'element is bound when manually inserted');
+    node.remove();
+    return node;
+  }).then(delay).then((node) {
+    expect(_unbound(node), true, reason:
+        'element is unbound when manually removed is called');
+  });
+}