Add Dismissable unit tests

examples/widgets/card_collection.dart

@@ -64,7 +64,7 @@ class CardCollectionApp extends App {
     });
   }
 
-  String dismissDirectionText(DismissDirection direction) {
+  String _dismissDirectionText(DismissDirection direction) {
     String s = direction.toString();
     return "dismiss ${s.substring(s.indexOf('.') + 1)}";
   }
@@ -85,7 +85,7 @@ class CardCollectionApp extends App {
         icon: icon,
         onPressed: () { changeDismissDirection(direction); },
         child: new Row([
-          new Flexible(child: new Text(dismissDirectionText(direction))),
+          new Flexible(child: new Text(_dismissDirectionText(direction))),
           new Radio(
             value: direction,
             onChanged: changeDismissDirection,
@@ -116,7 +116,7 @@ class CardCollectionApp extends App {
       left: new IconButton(icon: "navigation/menu", onPressed: _handleOpenDrawer),
       center: new Text('Swipe Away'),
       right: [
-        new Text(dismissDirectionText(_dismissDirection))
+        new Text(_dismissDirectionText(_dismissDirection))
       ]
     );
   }

sky/unit/test/widget/dismissable_test.dart

@@ -5,70 +5,201 @@ import 'package:test/test.dart';
 import '../engine/mock_events.dart';
 import 'widget_tester.dart';
 
+const double itemExtent = 100.0;
+ScrollDirection scrollDirection = ScrollDirection.vertical;
+DismissDirection dismissDirection = DismissDirection.horizontal;
+List<int> dismissedItems = [];
+
+void handleOnResized(item) {
+  expect(dismissedItems.contains(item), isFalse);
+}
+
+void handleOnDismissed(item) {
+  expect(dismissedItems.contains(item), isFalse);
+  dismissedItems.add(item);
+}
+
+Widget buildDismissableItem(int item) {
+  return new Dismissable(
+    key: new ValueKey<int>(item),
+    direction: dismissDirection,
+    onDismissed: () { handleOnDismissed(item); },
+    onResized: () { handleOnResized(item); },
+    child: new Container(
+      width: itemExtent,
+      height: itemExtent,
+      child: new Text(item.toString())
+    )
+  );
+}
+
+Widget widgetBuilder() {
+  return new Container(
+    padding: const EdgeDims.all(10.0),
+    child: new ScrollableList<int>(
+      items: [0, 1, 2, 3, 4],
+      itemBuilder: buildDismissableItem,
+      scrollDirection: scrollDirection,
+      itemExtent: itemExtent
+    )
+  );
+}
+
+void dismissItem(WidgetTester tester, int item, { DismissDirection gestureDirection }) {
+  assert(gestureDirection != DismissDirection.horizontal);
+  assert(gestureDirection != DismissDirection.vertical);
+
+  Widget itemWidget = tester.findText(item.toString());
+  expect(itemWidget, isNotNull);
+
+  Point downLocation;
+  Point upLocation;
+  switch(gestureDirection) {
+    case DismissDirection.left:
+      // Note: getTopRight() returns a point that's just beyond
+      // itemWidget's right edge and outside the Dismissable event
+      // listener's bounds.
+      downLocation = tester.getTopRight(itemWidget) + const Offset(-0.1, 0.0);
+      upLocation = tester.getTopLeft(itemWidget);
+      break;
+    case DismissDirection.right:
+      downLocation = tester.getTopLeft(itemWidget);
+      upLocation = tester.getTopRight(itemWidget);
+      break;
+    case DismissDirection.up:
+      // Note: getBottomLeft() returns a point that's just below
+      // itemWidget's bottom edge and outside the Dismissable event
+      // listener's bounds.
+      downLocation = tester.getBottomLeft(itemWidget) + const Offset(0.0, -0.1);
+      upLocation = tester.getTopLeft(itemWidget);
+      break;
+    case DismissDirection.down:
+      downLocation = tester.getTopLeft(itemWidget);
+      upLocation = tester.getBottomLeft(itemWidget);
+      break;
+  }
+
+  TestPointer pointer = new TestPointer(5);
+  tester.dispatchEvent(pointer.down(downLocation), downLocation);
+  tester.dispatchEvent(pointer.move(upLocation), downLocation);
+  tester.dispatchEvent(pointer.up(), downLocation);
+
+  double t0 = 0.0;
+  new FakeAsync().run((async) {
+    tester.pumpFrame(widgetBuilder, t0); // start the resize animation
+    tester.pumpFrame(widgetBuilder, t0 + 1000.0); // finish the resize animation
+    async.elapse(new Duration(seconds: 1));
+    tester.pumpFrame(widgetBuilder, t0 + 2000.0); // dismiss
+    async.elapse(new Duration(seconds: 1));
+  });
+}
+
 void main() {
-  test('Horizontal drag triggers dismiss', () {
+  test('Horizontal drag triggers dismiss scrollDirection=vertical', () {
+    WidgetTester tester = new WidgetTester();
+    scrollDirection = ScrollDirection.vertical;
+    dismissDirection = DismissDirection.horizontal;
+    dismissedItems = [];
+
+    tester.pumpFrame(widgetBuilder);
+    expect(dismissedItems, isEmpty);
+
+    dismissItem(tester, 0, gestureDirection: DismissDirection.right);
+    expect(tester.findText('0'), isNull);
+    expect(dismissedItems, equals([0]));
+
+    dismissItem(tester, 1, gestureDirection: DismissDirection.left);
+    expect(tester.findText('1'), isNull);
+    expect(dismissedItems, equals([0, 1]));
+  });
+
+  test('Vertical drag triggers dismiss scrollDirection=horizontal', () {
+    WidgetTester tester = new WidgetTester();
+    scrollDirection = ScrollDirection.horizontal;
+    dismissDirection = DismissDirection.vertical;
+    dismissedItems = [];
+
+    tester.pumpFrame(widgetBuilder);
+    expect(dismissedItems, isEmpty);
+
+    dismissItem(tester, 0, gestureDirection: DismissDirection.up);
+    expect(tester.findText('0'), isNull);
+    expect(dismissedItems, equals([0]));
+
+    dismissItem(tester, 1, gestureDirection: DismissDirection.down);
+    expect(tester.findText('1'), isNull);
+    expect(dismissedItems, equals([0, 1]));
+  });
+
+  test('drag-left with DismissDirection.left triggers dismiss', () {
+    WidgetTester tester = new WidgetTester();
+    scrollDirection = ScrollDirection.vertical;
+    dismissDirection = DismissDirection.left;
+    dismissedItems = [];
+
+    tester.pumpFrame(widgetBuilder);
+    expect(dismissedItems, isEmpty);
+
+    dismissItem(tester, 0, gestureDirection: DismissDirection.right);
+    expect(tester.findText('0'), isNotNull);
+    expect(dismissedItems, isEmpty);
+
+    dismissItem(tester, 0, gestureDirection: DismissDirection.left);
+    expect(tester.findText('0'), isNull);
+    expect(dismissedItems, equals([0]));
+  });
+
+  test('drag-right with DismissDirection.right triggers dismiss', () {
+    WidgetTester tester = new WidgetTester();
+    scrollDirection = ScrollDirection.vertical;
+    dismissDirection = DismissDirection.right;
+    dismissedItems = [];
+
+    tester.pumpFrame(widgetBuilder);
+    expect(dismissedItems, isEmpty);
+
+    dismissItem(tester, 0, gestureDirection: DismissDirection.left);
+    expect(tester.findText('0'), isNotNull);
+    expect(dismissedItems, isEmpty);
+
+    dismissItem(tester, 0, gestureDirection: DismissDirection.right);
+    expect(tester.findText('0'), isNull);
+    expect(dismissedItems, equals([0]));
+  });
+
+  test('drag-up with DismissDirection.up triggers dismiss', () {
+    WidgetTester tester = new WidgetTester();
+    scrollDirection = ScrollDirection.horizontal;
+    dismissDirection = DismissDirection.up;
+    dismissedItems = [];
+
+    tester.pumpFrame(widgetBuilder);
+    expect(dismissedItems, isEmpty);
+
+    dismissItem(tester, 0, gestureDirection: DismissDirection.down);
+    expect(tester.findText('0'), isNotNull);
+    expect(dismissedItems, isEmpty);
+
+    dismissItem(tester, 0, gestureDirection: DismissDirection.up);
+    expect(tester.findText('0'), isNull);
+    expect(dismissedItems, equals([0]));
+  });
+
+  test('drag-down with DismissDirection.down triggers dismiss', () {
     WidgetTester tester = new WidgetTester();
-    TestPointer pointer = new TestPointer(5);
-
-    const double itemHeight = 50.0;
-    List<int> dismissedItems = [];
-
-    void handleOnResized(item) {
-      expect(dismissedItems.contains(item), isFalse);
-    }
-
-    void handleOnDismissed(item) {
-      expect(dismissedItems.contains(item), isFalse);
-      dismissedItems.add(item);
-    }
-
-    Widget buildDismissableItem(int item) {
-      return new Dismissable(
-        key: new ValueKey<int>(item),
-        onDismissed: () { handleOnDismissed(item); },
-        onResized: () { handleOnResized(item); },
-        child: new Container(
-          height: itemHeight,
-          child: new Text(item.toString())
-        )
-      );
-    }
-
-    Widget builder() {
-      return new Container(
-        padding: const EdgeDims.all(10.0),
-        child: new ScrollableList<int>(
-          items: [0, 1, 2, 3, 4, 5],
-          itemBuilder: buildDismissableItem,
-          scrollDirection: ScrollDirection.vertical,
-          itemExtent: itemHeight
-        )
-      );
-    }
-
-    tester.pumpFrame(builder);
-    Widget item3 = tester.findText("3");
-    expect(item3, isNotNull);
+    scrollDirection = ScrollDirection.horizontal;
+    dismissDirection = DismissDirection.down;
+    dismissedItems = [];
+
+    tester.pumpFrame(widgetBuilder);
     expect(dismissedItems, isEmpty);
 
-    // Gesture: press-drag-release from the Dismissable's top-left corner
-    // to its top-right corner. Triggers the resize animation which concludes
-    // by calling onDismissed().
-    Point downLocation = tester.getTopLeft(item3);
-    Point upLocation = tester.getTopRight(item3);
-    tester.dispatchEvent(pointer.down(downLocation), downLocation);
-    tester.dispatchEvent(pointer.move(upLocation), upLocation);
-    tester.dispatchEvent(pointer.up(), upLocation);
-
-    new FakeAsync().run((async) {
-      tester.pumpFrame(builder); // start the resize animation
-      tester.pumpFrame(builder, 1000.0); // finish the resize animation
-      async.elapse(new Duration(seconds: 1));
-      tester.pumpFrame(builder, 2000.0); // dismiss
-      async.elapse(new Duration(seconds: 1));
-      expect(dismissedItems, equals([3]));
-      expect(tester.findText("3"), isNull);
-    });
+    dismissItem(tester, 0, gestureDirection: DismissDirection.up);
+    expect(tester.findText('0'), isNotNull);
+    expect(dismissedItems, isEmpty);
 
+    dismissItem(tester, 0, gestureDirection: DismissDirection.down);
+    expect(tester.findText('0'), isNull);
+    expect(dismissedItems, equals([0]));
   });
 }

sky/unit/test/widget/widget_tester.dart

@@ -76,25 +76,31 @@ class WidgetTester {
     });
   }
 
-  Point getCenter(Widget widget) {
+  Point _getWidgetPoint(Widget widget, Function sizeToPoint) {
     assert(widget != null);
     RenderBox box = widget.renderObject as RenderBox;
     assert(box != null);
-    return box.localToGlobal(box.size.center(Point.origin));
+    return box.localToGlobal(sizeToPoint(box.size));
+  }
+
+  Point getCenter(Widget widget) {
+    return _getWidgetPoint(widget, (Size size) => size.center(Point.origin));
   }
 
   Point getTopLeft(Widget widget) {
-    assert(widget != null);
-    RenderBox box = widget.renderObject as RenderBox;
-    assert(box != null);
-    return box.localToGlobal(Point.origin);
+    return _getWidgetPoint(widget, (_) => Point.origin);
   }
 
   Point getTopRight(Widget widget) {
-    assert(widget != null);
-    RenderBox box = widget.renderObject as RenderBox;
-    assert(box != null);
-    return box.localToGlobal(box.size.topRight(Point.origin));
+    return _getWidgetPoint(widget, (Size size) => size.topRight(Point.origin));
+  }
+
+  Point getBottomLeft(Widget widget) {
+    return _getWidgetPoint(widget, (Size size) => size.bottomLeft(Point.origin));
+  }
+
+  Point getBottomRight(Widget widget) {
+    return _getWidgetPoint(widget, (Size size) => size.bottomRight(Point.origin));
   }
 
   HitTestResult _hitTest(Point location) => SkyBinding.instance.hitTest(location);