Adds a lot of missing IsWidget support, especially for UiBinder. Addresses http://code.google.com/p/google-web-toolkit/issues/detail?id=5879 Review by rjrjr@google.com http://gwt-code-reviews.appspot.com/1295806 Review by: sbrubaker@google.com git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@9744 8db76d5a-ed1c-0410-87a9-c151d255dfc7

diff --git a/user/src/com/google/gwt/uibinder/elementparsers/HasTreeItemsParser.java b/user/src/com/google/gwt/uibinder/elementparsers/HasTreeItemsParser.java
index 6151afa..18bca99 100644
--- a/user/src/com/google/gwt/uibinder/elementparsers/HasTreeItemsParser.java
+++ b/user/src/com/google/gwt/uibinder/elementparsers/HasTreeItemsParser.java

@@ -19,6 +19,7 @@
 import com.google.gwt.core.ext.typeinfo.JClassType;
 import com.google.gwt.uibinder.rebind.UiBinderWriter;
 import com.google.gwt.uibinder.rebind.XMLElement;
+import com.google.gwt.user.client.ui.IsWidget;
 import com.google.gwt.user.client.ui.TreeItem;
 import com.google.gwt.user.client.ui.Widget;
 
@@ -34,6 +35,7 @@
     // Prepare base types.
     JClassType itemType = writer.getOracle().findType(TreeItem.class.getName());
     JClassType widgetType = writer.getOracle().findType(Widget.class.getName());
+    JClassType isWidgetType = writer.getOracle().findType(IsWidget.class.getName());
 
     // Parse children.
     for (XMLElement child : elem.consumeChildElements()) {
@@ -46,8 +48,8 @@
         continue;
       }
 
-      // Widget+
-      if (widgetType.isAssignableFrom(childType)) {
+      // Widget+ or IsWidget+
+      if (widgetType.isAssignableFrom(childType) || isWidgetType.isAssignableFrom(childType)) {
         String childFieldName = writer.parseElementToField(child);
         writer.addStatement("%1$s.addItem(%2$s);", fieldName, childFieldName);
         continue;

diff --git a/user/src/com/google/gwt/user/client/ui/AbsolutePanel.java b/user/src/com/google/gwt/user/client/ui/AbsolutePanel.java
index 66bb445..9fe27ca 100644
--- a/user/src/com/google/gwt/user/client/ui/AbsolutePanel.java
+++ b/user/src/com/google/gwt/user/client/ui/AbsolutePanel.java

@@ -117,6 +117,15 @@
     insert(w, beforeIndex);
     verifyPositionNotStatic(w);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #add(Widget,int,int)
+   */
+  public void add(IsWidget w, int left, int top) {
+    this.add(w.asWidget(),left,top);
+  }
 
   /**
    * Gets the position of the left outer border edge of the widget relative to

diff --git a/user/src/com/google/gwt/user/client/ui/CaptionPanel.java b/user/src/com/google/gwt/user/client/ui/CaptionPanel.java
index 5fda0ff..647bc79 100644
--- a/user/src/com/google/gwt/user/client/ui/CaptionPanel.java
+++ b/user/src/com/google/gwt/user/client/ui/CaptionPanel.java

@@ -31,7 +31,7 @@
  * the upper left corner of the border. This is an implementation of the
  * fieldset HTML element.
  */
-public class CaptionPanel extends Composite implements HasWidgets {
+public class CaptionPanel extends Composite implements HasWidgets.ForIsWidget {
   /**
    * Implementation class without browser-specific hacks.
    */
@@ -165,6 +165,15 @@
   public void add(Widget w) {
     ((SimplePanel) getWidget()).add(w);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #add(Widget)
+   */
+  public void add(IsWidget w) {
+    this.add(asWidgetOrNull(w));
+  }
 
   /**
    * Removes the content widget.
@@ -220,6 +229,15 @@
   public boolean remove(Widget w) {
     return ((SimplePanel) getWidget()).remove(w);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #remove(Widget)
+   */
+  public boolean remove(IsWidget w) {
+    return this.remove(asWidgetOrNull(w));
+  }
 
   /**
    * Sets the caption for the panel using an HTML fragment. Pass in empty string

diff --git a/user/src/com/google/gwt/user/client/ui/CellPanel.java b/user/src/com/google/gwt/user/client/ui/CellPanel.java
index 4c238fc..43be0b1 100644
--- a/user/src/com/google/gwt/user/client/ui/CellPanel.java
+++ b/user/src/com/google/gwt/user/client/ui/CellPanel.java

@@ -110,6 +110,15 @@
       td.setPropertyString("height", height);
     }
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setCellHeight(Widget,String)
+   */
+  public void setCellHeight(IsWidget w, String height) {
+    this.setCellHeight(w.asWidget(), height);
+  }
 
   /**
    * Sets the horizontal alignment of the given widget within its cell.
@@ -125,6 +134,16 @@
       setCellHorizontalAlignment(td, align);
     }
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setCellHorizontalAlignment(Widget,HorizontalAlignmentConstant)
+   */
+  public void setCellHorizontalAlignment(IsWidget w,
+      HorizontalAlignmentConstant align) {
+    this.setCellHorizontalAlignment(w.asWidget(), align);
+  }
 
   /**
    * Sets the vertical alignment of the given widget within its cell.
@@ -139,6 +158,15 @@
       setCellVerticalAlignment(td, align);
     }
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setCellVerticalAlignment(Widget,VerticalAlignmentConstant)
+   */
+  public void setCellVerticalAlignment(IsWidget w, VerticalAlignmentConstant align) {
+    this.setCellVerticalAlignment(w.asWidget(),align);
+  }
 
   /**
    * Sets the width of the cell associated with the given widget, related to the
@@ -153,6 +181,15 @@
       td.setPropertyString("width", width);
     }
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setCellWidth(Widget,String)
+   */
+  public void setCellWidth(IsWidget w, String width) {
+    this.setCellWidth(w.asWidget(), width);
+  }
 
   /**
    * Sets the amount of spacing between this panel's cells.

diff --git a/user/src/com/google/gwt/user/client/ui/DisclosurePanel.java b/user/src/com/google/gwt/user/client/ui/DisclosurePanel.java
index a140939..506ef09 100644
--- a/user/src/com/google/gwt/user/client/ui/DisclosurePanel.java
+++ b/user/src/com/google/gwt/user/client/ui/DisclosurePanel.java

@@ -81,7 +81,7 @@
  */
 @SuppressWarnings("deprecation")
 public final class DisclosurePanel extends Composite implements
-    FiresDisclosureEvents, HasWidgets, HasAnimation,
+    FiresDisclosureEvents, HasWidgets.ForIsWidget, HasAnimation,
     HasOpenHandlers<DisclosurePanel>, HasCloseHandlers<DisclosurePanel> {
   interface DefaultImages extends ClientBundle {
     @ImageOptions(flipRtl = true)
@@ -456,6 +456,15 @@
           "A DisclosurePanel can only contain two Widgets.");
     }
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #add(Widget)
+   */
+  public void add(IsWidget w) {
+    this.add(asWidgetOrNull(w));
+  }
 
   public HandlerRegistration addCloseHandler(
       CloseHandler<DisclosurePanel> handler) {
@@ -538,6 +547,15 @@
     }
     return false;
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #remove(Widget)
+   */
+  public boolean remove(IsWidget w) {
+    return this.remove(asWidgetOrNull(w));
+  }
 
   /**
    * Removes an event handler from the panel.

diff --git a/user/src/com/google/gwt/user/client/ui/DockLayoutPanel.java b/user/src/com/google/gwt/user/client/ui/DockLayoutPanel.java
index a07d933..fcf6dab 100644
--- a/user/src/com/google/gwt/user/client/ui/DockLayoutPanel.java
+++ b/user/src/com/google/gwt/user/client/ui/DockLayoutPanel.java

@@ -161,6 +161,15 @@
   }
 
   /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #addEast(Widget,double)
+   */
+  public void addEast(IsWidget widget, double size) {
+    this.addEast(widget.asWidget(), size);
+  }
+  
+  /**
    * Adds a widget to the end of the line. In LTR mode, the widget is added to
    * the east. In RTL mode, the widget is added to the west.
    *
@@ -191,6 +200,15 @@
   public void addNorth(Widget widget, double size) {
     insert(widget, Direction.NORTH, size, null);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #addNorth(Widget,double)
+   */
+  public void addNorth(IsWidget widget, double size) {
+    this.addNorth(widget.asWidget(), size);
+  }
 
   /**
    * Adds a widget to the south edge of the dock.
@@ -201,6 +219,15 @@
   public void addSouth(Widget widget, double size) {
     insert(widget, Direction.SOUTH, size, null);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #addSouth(Widget,double)
+   */
+  public void addSouth(IsWidget widget, double size) {
+    this.addSouth(widget.asWidget(), size);
+  }
 
   /**
    * Adds a widget to the west edge of the dock.
@@ -211,6 +238,15 @@
   public void addWest(Widget widget, double size) {
     insert(widget, Direction.WEST, size, null);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #addWest(Widget,double)
+   */
+  public void addWest(IsWidget widget, double size) {
+    this.addWest(widget.asWidget(), size);
+  }
 
   public void animate(int duration) {
     animate(duration, null);

diff --git a/user/src/com/google/gwt/user/client/ui/DockPanel.java b/user/src/com/google/gwt/user/client/ui/DockPanel.java
index f6e1cce..952d60e 100644
--- a/user/src/com/google/gwt/user/client/ui/DockPanel.java
+++ b/user/src/com/google/gwt/user/client/ui/DockPanel.java

@@ -196,7 +196,16 @@
     // Adopt.
     adopt(widget);
   }
-
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #add(Widget,DockLayoutConstant)
+   */
+  public void add(IsWidget widget, DockLayoutConstant direction) {
+   this.add(widget.asWidget(), direction);
+  }
+  
   public HorizontalAlignmentConstant getHorizontalAlignment() {
     return horzAlign;
   }

diff --git a/user/src/com/google/gwt/user/client/ui/HTMLPanel.java b/user/src/com/google/gwt/user/client/ui/HTMLPanel.java
index 2240ac7..e2a5091 100644
--- a/user/src/com/google/gwt/user/client/ui/HTMLPanel.java
+++ b/user/src/com/google/gwt/user/client/ui/HTMLPanel.java

@@ -201,6 +201,16 @@
   }
   
   /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #addAndReplaceElement(Widget,Element)
+   */
+  public void addAndReplaceElement(IsWidget widget,
+      com.google.gwt.user.client.Element toReplace) {
+    this.addAndReplaceElement(widget.asWidget(),toReplace);
+  }
+  
+  /**
    * Adds a child widget to the panel, replacing the HTML element specified by a
    * given id.
    * 
@@ -218,6 +228,15 @@
   }
   
   /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #addAndReplaceElement(Widget,String)
+   */
+  public void addAndReplaceElement(IsWidget widget, String id) {
+    this.addAndReplaceElement(widget.asWidget(), id);
+  }
+  
+  /**
    * Finds an {@link Element element} within this panel by its id.
    * 
    * This method uses

diff --git a/user/src/com/google/gwt/user/client/ui/HTMLTable.java b/user/src/com/google/gwt/user/client/ui/HTMLTable.java
index 5155ffe..6a0d499 100644
--- a/user/src/com/google/gwt/user/client/ui/HTMLTable.java
+++ b/user/src/com/google/gwt/user/client/ui/HTMLTable.java

@@ -1114,6 +1114,15 @@
       adopt(widget);
     }
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setWidget(int,int,Widget)
+   */
+  public void setWidget(int row, int column, IsWidget widget) {
+    this.setWidget(row, column, asWidgetOrNull(widget));
+  }
 
   /**
    * Bounds checks that the cell exists at the specified location.

diff --git a/user/src/com/google/gwt/user/client/ui/HasTreeItems.java b/user/src/com/google/gwt/user/client/ui/HasTreeItems.java
index d8caf16..cb7ba1e 100644
--- a/user/src/com/google/gwt/user/client/ui/HasTreeItems.java
+++ b/user/src/com/google/gwt/user/client/ui/HasTreeItems.java

@@ -22,7 +22,14 @@
  * {@link com.google.gwt.user.client.ui.TreeItem items} and can operate them.
  */
 public interface HasTreeItems {
-  
+
+  /**
+   * Extends this interface with convenience methods to handle {@link IsWidget}.
+   */
+  interface ForIsWidget extends HasTreeItems {
+    TreeItem addItem(IsWidget w);
+  }
+
   /**
    * Adds a simple tree item containing the specified html.
    * 
@@ -37,7 +44,7 @@
    * @param item the item to be added
    */
   void addItem(TreeItem item);
-  
+
   /**
    * Adds an item wrapped by specified {@link IsTreeItem}.
    * 
@@ -52,7 +59,7 @@
    * @return the new item
    */
   TreeItem addItem(Widget widget);
-  
+
   /**
    * Adds a simple tree item containing the specified text.
    * 
@@ -67,7 +74,7 @@
    * @param item the item to be removed
    */
   void removeItem(TreeItem item);
-  
+
   /**
    * Removes an item.
    * 

diff --git a/user/src/com/google/gwt/user/client/ui/LayoutPanel.java b/user/src/com/google/gwt/user/client/ui/LayoutPanel.java
index 52f2ebb..4662c7a 100644
--- a/user/src/com/google/gwt/user/client/ui/LayoutPanel.java
+++ b/user/src/com/google/gwt/user/client/ui/LayoutPanel.java

@@ -231,6 +231,16 @@
   }
 
   /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setWidgetBottomHeight(Widget,double, Unit, double, Unit)
+   */
+  public void setWidgetBottomHeight(IsWidget child, double bottom,
+      Unit bottomUnit, double height, Unit heightUnit) {
+    this.setWidgetBottomHeight(child.asWidget(), bottom, bottomUnit, height, heightUnit);
+  }
+  
+  /**
    * Sets the child widget's horizontal position within its layer.
    * 
    * @param child
@@ -257,6 +267,16 @@
     getLayer(child).setLeftRight(left, leftUnit, right, rightUnit);
     animate(0);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setWidgetLeftRight(Widget,double, Unit, double, Unit)
+   */
+  public void setWidgetLeftRight(IsWidget child, double left, Unit leftUnit,
+      double right, Unit rightUnit) {
+    this.setWidgetLeftRight(child.asWidget(), left, leftUnit, right, rightUnit);
+  }
 
   /**
    * Sets the child widget's left and width values.
@@ -273,6 +293,16 @@
     getLayer(child).setLeftWidth(left, leftUnit, width, widthUnit);
     animate(0);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setWidgetLeftWidth(Widget,double, Unit, double, Unit)
+   */
+  public void setWidgetLeftWidth(IsWidget child, double left, Unit leftUnit,
+      double width, Unit widthUnit) {
+    this.setWidgetLeftWidth(child.asWidget(), left, leftUnit, width, widthUnit);
+  }
 
   /**
    * Sets the child widget's right and width values.
@@ -289,6 +319,16 @@
     getLayer(child).setRightWidth(right, rightUnit, width, widthUnit);
     animate(0);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setWidgetRightWidth(Widget,double, Unit, double, Unit)
+   */
+  public void setWidgetRightWidth(IsWidget child, double right, Unit rightUnit,
+      double width, Unit widthUnit) {
+    this.setWidgetRightWidth(child.asWidget(), right, rightUnit, width, widthUnit);
+  }
 
   /**
    * Sets the child widget's top and bottom values.
@@ -305,6 +345,16 @@
     getLayer(child).setTopBottom(top, topUnit, bottom, bottomUnit);
     animate(0);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setWidgetTopBottom(Widget,double, Unit, double, Unit)
+   */
+  public void setWidgetTopBottom(IsWidget child, double top, Unit topUnit,
+      double bottom, Unit bottomUnit) {
+    this.setWidgetTopBottom(child.asWidget(), top, topUnit, bottom, bottomUnit);
+  }
 
   /**
    * Sets the child widget's top and height values.
@@ -321,6 +371,16 @@
     getLayer(child).setTopHeight(top, topUnit, height, heightUnit);
     animate(0);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #setWidgetTopHeight(Widget,double, Unit, double, Unit)
+   */
+  public void setWidgetTopHeight(IsWidget child, double top, Unit topUnit,
+      double height, Unit heightUnit) {
+    this.setWidgetTopHeight(child.asWidget(), top, topUnit, height, heightUnit);
+  }
 
   /**
    * Sets the child widget's vertical position within its layer.

diff --git a/user/src/com/google/gwt/user/client/ui/StackLayoutPanel.java b/user/src/com/google/gwt/user/client/ui/StackLayoutPanel.java
index 9ea1e6a..1f03c78 100644
--- a/user/src/com/google/gwt/user/client/ui/StackLayoutPanel.java
+++ b/user/src/com/google/gwt/user/client/ui/StackLayoutPanel.java

@@ -179,6 +179,15 @@
   public void add(final Widget widget, String header, boolean asHtml, double headerSize) {
     insert(widget, header, asHtml, headerSize, getWidgetCount());
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #add(Widget,String,boolean,double)
+   */
+  public void add(final IsWidget widget, String header, boolean asHtml, double headerSize) {
+    this.add(widget.asWidget(), header, asHtml, headerSize);
+  }
 
   /**
    * Adds a child widget to this stack, along with a widget representing the
@@ -204,6 +213,15 @@
     insert(widget, header, headerSize, getWidgetCount());
   }
 
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #add(Widget,Widget,double)
+   */
+  public void add(final IsWidget widget, IsWidget header, double headerSize) {
+    this.add(widget.asWidget(), header.asWidget(), headerSize);
+  }
+  
   public HandlerRegistration addBeforeSelectionHandler(
       BeforeSelectionHandler<Integer> handler) {
     return addHandler(handler, BeforeSelectionEvent.getType());

diff --git a/user/src/com/google/gwt/user/client/ui/Tree.java b/user/src/com/google/gwt/user/client/ui/Tree.java
index 5745374..a032a38 100644
--- a/user/src/com/google/gwt/user/client/ui/Tree.java
+++ b/user/src/com/google/gwt/user/client/ui/Tree.java

@@ -89,7 +89,7 @@
  * </p>
  */
 @SuppressWarnings("deprecation")
-public class Tree extends Widget implements HasTreeItems, HasWidgets, 
+public class Tree extends Widget implements HasTreeItems.ForIsWidget, HasWidgets.ForIsWidget, 
     SourcesTreeEvents, HasFocus, HasAnimation, HasAllKeyHandlers,
     HasAllFocusHandlers, HasSelectionHandlers<TreeItem>,
     HasOpenHandlers<TreeItem>, HasCloseHandlers<TreeItem>, SourcesMouseEvents,
@@ -303,6 +303,15 @@
   public void add(Widget widget) {
     addItem(widget);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #add(Widget)
+   */
+  public void add(IsWidget w) {
+    this.add(asWidgetOrNull(w));
+  }
 
   public HandlerRegistration addBlurHandler(BlurHandler handler) {
     return addDomHandler(handler, BlurEvent.getType());
@@ -371,6 +380,15 @@
   public TreeItem addItem(Widget widget) {
     return root.addItem(widget);
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #addItem(Widget)
+   */
+  public TreeItem addItem(IsWidget w) {
+    return this.addItem(asWidgetOrNull(w));
+  }
 
   /**
    * @deprecated Use {@link #addKeyDownHandler}, {@link #addKeyUpHandler} and
@@ -679,6 +697,15 @@
     item.setWidget(null);
     return true;
   }
+  
+  /**
+   * Overloaded version for IsWidget.
+   * 
+   * @see #remove(Widget)
+   */
+  public boolean remove(IsWidget w) {
+    return this.remove(w.asWidget());
+  }
 
   /**
    * @deprecated Use the {@link HandlerRegistration#removeHandler} method on the

diff --git a/user/test/com/google/gwt/layout/client/LayerFriend.java b/user/test/com/google/gwt/layout/client/LayerFriend.java
new file mode 100644
index 0000000..6090a3b
--- /dev/null
+++ b/user/test/com/google/gwt/layout/client/LayerFriend.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2011 Google Inc.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.google.gwt.layout.client;
+
+import com.google.gwt.dom.client.Style.Unit;
+import com.google.gwt.layout.client.Layout.Layer;
+
+/**
+ * A helper class to gain access to the package protected internals of a
+ * {@link Layout.Layer} from other packages. For testing purposes.
+ * 
+ */
+public class LayerFriend {
+
+  private Layer layer;
+
+  public LayerFriend(Layer layer) {
+    this.layer = layer;
+  }
+  
+  public double getTop() {
+    return layer.top;
+  }
+  
+  public Unit getTopUnit() {
+    return layer.topUnit;
+  }
+  
+  public double getBottom() {
+    return layer.bottom;
+  }
+  
+  public Unit getBottomUnit() {
+    return layer.bottomUnit;
+  }
+  
+  public double getRight() {
+    return layer.right;
+  }
+  
+  public Unit getRightUnit() {
+    return layer.rightUnit;
+  }
+  
+  public double getLeft() {
+    return layer.left;
+  }
+  
+  public Unit getLeftUnit() {
+    return layer.leftUnit;
+  }
+  
+  public double getHeight() {
+    return layer.height;
+  }
+  
+  public Unit getHeightUnit() {
+    return layer.heightUnit;
+  }
+  
+  public double getWidth() {
+    return layer.width;
+  }
+  
+  public Unit getWidthUnit() {
+    return layer.widthUnit;
+  }
+
+}

diff --git a/user/test/com/google/gwt/uibinder/elementparsers/HasTreeItemsParserTest.java b/user/test/com/google/gwt/uibinder/elementparsers/HasTreeItemsParserTest.java
index 10c311f..692e1a2 100644
--- a/user/test/com/google/gwt/uibinder/elementparsers/HasTreeItemsParserTest.java
+++ b/user/test/com/google/gwt/uibinder/elementparsers/HasTreeItemsParserTest.java

@@ -85,6 +85,18 @@
     assertStatements("fieldName.addItem(<g:Button text='1'>);",
         "fieldName.addItem(<g:Button text='2'>);");
   }
+  
+  public void test_IsWidget() throws Exception {
+    StringBuffer b = new StringBuffer();
+    b.append("<g:Tree>");
+    b.append("  <g:IsWidget />");
+    b.append("  <g:IsWidget />");
+    b.append("</g:Tree>"); 
+    // parse
+    tester.parse(b.toString());
+    assertStatements("fieldName.addItem(<g:IsWidget>);",
+        "fieldName.addItem(<g:IsWidget>);");
+  }
 
   public void test_WidgetItemMix() throws Exception {
     StringBuffer b = new StringBuffer();

diff --git a/user/test/com/google/gwt/uibinder/test/UiJavaResources.java b/user/test/com/google/gwt/uibinder/test/UiJavaResources.java
index 5d218e9..22678eb 100644
--- a/user/test/com/google/gwt/uibinder/test/UiJavaResources.java
+++ b/user/test/com/google/gwt/uibinder/test/UiJavaResources.java

@@ -300,6 +300,18 @@
       return code;
     }
   };
+  public static final MockJavaResource IS_WIDGET = new MockJavaResource(
+      "com.google.gwt.user.client.ui.IsWidget") {
+    @Override
+    protected CharSequence getContent() {
+      StringBuffer code = new StringBuffer();
+      code.append("package com.google.gwt.user.client.ui;\n");
+      code.append("public interface IsWidget  {\n");
+      code.append("  Widget asWidget();\n");
+      code.append("}\n");
+      return code;
+    }
+  };
   public static final MockJavaResource LABEL = new MockJavaResource(
       "com.google.gwt.user.client.ui.Label") {
     @Override
@@ -635,6 +647,7 @@
     rtn.add(GWT_EVENT);
     rtn.add(IMAGE);
     rtn.add(IMAGE_RESOURCE);
+    rtn.add(IS_WIDGET);
     rtn.add(HANDLER_REGISTRATION);
     rtn.add(HAS_CLICK_HANDLERS);
     rtn.add(HAS_HORIZONTAL_ALIGNMENT);

diff --git a/user/test/com/google/gwt/user/client/ui/AbsolutePanelTest.java b/user/test/com/google/gwt/user/client/ui/AbsolutePanelTest.java
index 966fcda..fb07d8f 100644
--- a/user/test/com/google/gwt/user/client/ui/AbsolutePanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/AbsolutePanelTest.java

@@ -16,6 +16,7 @@
 package com.google.gwt.user.client.ui;
 
 import com.google.gwt.dom.client.Document;
+import com.google.gwt.dom.client.Element;
 import com.google.gwt.junit.DoNotRunWith;
 import com.google.gwt.junit.Platform;
 import com.google.gwt.user.client.Window;
@@ -31,7 +32,7 @@
    * would throw an {@link IndexOutOfBoundsException}.
    */
   public void testDoubleAdd() {
-    AbsolutePanel absolutePanel = new AbsolutePanel();
+    AbsolutePanel absolutePanel = createPanel();
     Label label = new Label("label");
 
     absolutePanel.add(label, 10, 10);
@@ -39,13 +40,40 @@
   }
 
   /**
-   * Failed in all modes with absolute positioning.
-   * TODO: (flin) File a new HtmlUnit bug.
+   * Ensures that add(Widget, int, int) adds the Widget as its child.
+   */
+  public void testAdd() {
+    AbsolutePanel absolutePanel = createPanel();
+    Label label = new Label("foo");
+
+    absolutePanel.add(label, 10, 10);
+
+    assertLogicalPaternity(absolutePanel, label);
+    assertPhysicalPaternity(absolutePanel, label);
+  }
+
+  /**
+   * Ensures that add(IsWidget, int, int) adds the Widget as its child.
+   */
+  public void testAddAsIsWidget() {
+    AbsolutePanel absolutePanel = createPanel();
+    Label label = new Label("foo");
+
+    // IsWidget cast to call the overloaded version
+    absolutePanel.add((IsWidget) label, 10, 10);
+
+    assertLogicalPaternity(absolutePanel, label);
+    assertPhysicalPaternity(absolutePanel, label);
+  }
+
+  /**
+   * Failed in all modes with absolute positioning. TODO: (flin) File a new
+   * HtmlUnit bug.
    */
   @DoNotRunWith(Platform.HtmlUnitBug)
   public void testPositioning() {
     // Make an absolute panel with a label at (3, 7).
-    AbsolutePanel abs = new AbsolutePanel();
+    AbsolutePanel abs = createPanel();
     abs.setSize("128px", "128px");
     Label lbl = new Label("foo");
     abs.add(lbl, 3, 7);
@@ -73,7 +101,8 @@
     int absY = lbl.getAbsoluteTop() - Document.get().getBodyOffsetTop();
     assertEquals(3, x);
     assertEquals(7, y);
-    assertEquals("absX should be 103. This will fail in WebKit if run headless", 
+    assertEquals(
+        "absX should be 103. This will fail in WebKit if run headless",
         3 + 100, absX);
     assertEquals(7 + 200, absY);
   }
@@ -82,4 +111,35 @@
   protected AbsolutePanel createPanel() {
     return new AbsolutePanel();
   }
+
+  /**
+   * Asserts that <b>panel</b> is the logical parent of <b>expectedChild</b>.
+   * 
+   * @param panel the parent panel
+   * @param expectedChild the expected child of <b>panel</b>
+   */
+  private void assertLogicalPaternity(ComplexPanel panel, Widget expectedChild) {
+    assertSame("The parent and the panel must be the same", panel,
+        expectedChild.getParent());
+    assertTrue("The child must be in the childen collection of the panel",
+        panel.getChildren().contains(expectedChild));
+  }
+
+  /**
+   * Asserts that <b>expectedFirstChild</b> is the first physical child of
+   * <b>panel</b>.
+   * 
+   * @param panel the parent panel
+   * @param expectedFirstChild the expected first child of <b>panel</b>
+   */
+  private void assertPhysicalPaternity(ComplexPanel panel,
+      Widget expectedFirstChild) {
+    Element panelElement = panel.getElement();
+    Element childElement = expectedFirstChild.getElement();
+    assertSame("The parent's Element of the child must be the panel's Element",
+        panelElement, childElement.getParentElement());
+    assertSame(
+        "The child's Element must be first child of the panel's Element",
+        childElement, panelElement.getFirstChildElement());
+  }
 }

diff --git a/user/test/com/google/gwt/user/client/ui/AbstractCellPanelTest.java b/user/test/com/google/gwt/user/client/ui/AbstractCellPanelTest.java
index 55f5ebe..f98c5c5 100644
--- a/user/test/com/google/gwt/user/client/ui/AbstractCellPanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/AbstractCellPanelTest.java

@@ -22,19 +22,30 @@
  * 
  * @param <T> the panel type
  */
-public abstract class AbstractCellPanelTest<T extends CellPanel> extends PanelTestBase<T> {
+public abstract class AbstractCellPanelTest<T extends CellPanel> extends
+    PanelTestBase<T> {
 
   @Override
   public String getModuleName() {
     return "com.google.gwt.user.DebugTest";
   }
 
+  /**
+   * Test {@link CellPanel#getWidgetTd(Widget)}.
+   */
   public void testGetWidgetTd() {
     CellPanel panel = createCellPanel();
     Widget w = panel.getWidget(0);
     assertEquals(w.getElement().getParentElement(), panel.getWidgetTd(w));
   }
 
+  /**
+   * Tests
+   * {@link CellPanel#setCellVerticalAlignment(Widget, com.google.gwt.user.client.ui.HasVerticalAlignment.VerticalAlignmentConstant)}
+   * and
+   * {@link CellPanel#setCellHorizontalAlignment(Widget, com.google.gwt.user.client.ui.HasHorizontalAlignment.HorizontalAlignmentConstant)}
+   * .
+   */
   public void testSetCellAlignment() {
     CellPanel panel = createCellPanel();
     Widget w = panel.getWidget(0);
@@ -49,6 +60,39 @@
     assertEquals("right", td.getPropertyString("align"));
   }
 
+  /**
+   * Tests
+   * {@link CellPanel#setCellVerticalAlignment(IsWidget, com.google.gwt.user.client.ui.HasVerticalAlignment.VerticalAlignmentConstant)}
+   * and
+   * {@link CellPanel#setCellHorizontalAlignment(IsWidget, com.google.gwt.user.client.ui.HasHorizontalAlignment.HorizontalAlignmentConstant)}
+   * .
+   */
+  public void testSetCellAlignmentAsIsWidget() {
+    CellPanel panel = createCellPanel();
+    Widget w = panel.getWidget(0);
+    Element td = panel.getWidgetTd(w);
+
+    // setCellVerticalAlignment
+    // IsWidget cast to call the overloaded version
+    panel.setCellVerticalAlignment((IsWidget) w,
+        HasVerticalAlignment.ALIGN_BOTTOM);
+    assertEquals("bottom", td.getStyle().getProperty("verticalAlign"));
+
+    // setCellHorizontalAlignment
+    // IsWidget reference to call the overloaded version
+    panel.setCellHorizontalAlignment((IsWidget) w,
+        HasHorizontalAlignment.ALIGN_RIGHT);
+    assertEquals("right", td.getPropertyString("align"));
+  }
+
+  /**
+   * Ensures that
+   * {@link CellPanel#setCellVerticalAlignment(Widget, com.google.gwt.user.client.ui.HasVerticalAlignment.VerticalAlignmentConstant)}
+   * and
+   * {@link CellPanel#setCellHorizontalAlignment(Widget, com.google.gwt.user.client.ui.HasHorizontalAlignment.HorizontalAlignmentConstant)}
+   * don't throw an Exception when the Widget argument is not a child of the
+   * panel.
+   */
   public void testSetCellAlignmentForNonChildWidget() {
     CellPanel panel = createCellPanel();
     Widget w = new Label("Not a chid");
@@ -60,6 +104,30 @@
     panel.setCellHorizontalAlignment(w, HasHorizontalAlignment.ALIGN_RIGHT);
   }
 
+  /**
+   * Ensures that
+   * {@link CellPanel#setCellVerticalAlignment(IsWidget, com.google.gwt.user.client.ui.HasVerticalAlignment.VerticalAlignmentConstant)}
+   * and
+   * {@link CellPanel#setCellHorizontalAlignment(IsWidget, com.google.gwt.user.client.ui.HasHorizontalAlignment.HorizontalAlignmentConstant)}
+   * don't throw an Exception when the IsWidget argument is not a child of the
+   * panel.
+   */
+  public void testSetCellAlignmentForNonChildWidgetAsIsWidget() {
+    CellPanel panel = createCellPanel();
+    // IsWidget reference to call the overloaded version
+    IsWidget w = new Label("Not a chid");
+
+    // setCellVerticalAlignment should not throw an error
+    panel.setCellVerticalAlignment(w, HasVerticalAlignment.ALIGN_BOTTOM);
+
+    // setCellHorizontalAlignment should not throw an error
+    panel.setCellHorizontalAlignment(w, HasHorizontalAlignment.ALIGN_RIGHT);
+  }
+
+  /**
+   * Tests {@link CellPanel#setCellHeight(Widget, String)} and
+   * {@link CellPanel#setCellWidth(Widget, String)}.
+   */
   public void testSetCellSize() {
     CellPanel panel = createCellPanel();
     Widget w = panel.getWidget(0);
@@ -74,6 +142,31 @@
     assertEquals(200, td.getPropertyInt("width"));
   }
 
+  /**
+   * Tests {@link CellPanel#setCellHeight(IsWidget, String)} and
+   * {@link CellPanel#setCellWidth(IsWidget, String)}.
+   */
+  public void testSetCellSizeAsIsWidget() {
+    CellPanel panel = createCellPanel();
+    Widget w = panel.getWidget(0);
+    Element td = panel.getWidgetTd(w);
+
+    // setCellHeight
+    // IsWidget cast to call the overloaded version
+    panel.setCellHeight((IsWidget) w, "100px");
+    assertEquals(100, td.getPropertyInt("height"));
+
+    // setCellWidth
+    // IsWidget cast to call the overloaded version
+    panel.setCellWidth((IsWidget) w, "200px");
+    assertEquals(200, td.getPropertyInt("width"));
+  }
+
+  /**
+   * Ensures that {@link CellPanel#setCellHeight(Widget, String)} and
+   * {@link CellPanel#setCellWidth(Widget, String)} don't throw an Exception
+   * when the Widget argument is not a child of the panel.
+   */
   public void testSetCellSizeForNonChildWidget() {
     CellPanel panel = createCellPanel();
     Widget w = new Label("Not a chid");
@@ -86,6 +179,24 @@
   }
 
   /**
+   * Ensures that {@link CellPanel#setCellHeight(IsWidget, String)} and
+   * {@link CellPanel#setCellWidth(IsWidget, String)} don't throw an Exception
+   * when the IsWidget argument is not a child of the panel.
+   */
+  public void testSetCellSizeForNonChildWidgetAsIsWidget() {
+    CellPanel panel = createCellPanel();
+    Widget w = new Label("Not a chid");
+
+    // setCellHeight should not throw an error
+    // IsWidget cast to call the overloaded version
+    panel.setCellHeight((IsWidget) w, "100px");
+
+    // setCellWidth should not throw an error
+    // IsWidget cast to call the overloaded version
+    panel.setCellWidth((IsWidget) w, "200px");
+  }
+
+  /**
    * Create a populated {@link CellPanel}.
    * 
    * @return the {@link CellPanel}

diff --git a/user/test/com/google/gwt/user/client/ui/CaptionPanelTest.java b/user/test/com/google/gwt/user/client/ui/CaptionPanelTest.java
index 13d195b..357b7a8 100644
--- a/user/test/com/google/gwt/user/client/ui/CaptionPanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/CaptionPanelTest.java

@@ -32,11 +32,38 @@
     return "com.google.gwt.user.User";
   }
 
+  /**
+   * Tests {@link CaptionPanel#add(IsWidget)}.
+   */
+  public void testAddAsIsWidget() {
+    CaptionPanel panel = createEmptyCaptionPanel();
+    Widget widget = new Label("foo");
+    
+    // IsWidget cast to call the overloaded version
+    panel.add((IsWidget) widget);
+    
+    assertSame(widget,panel.getContentWidget());
+  }
+  
+  /**
+   * Ensures that {@link CaptionPanel#add(IsWidget)} does <b>NOT</b> fail
+   * when the IsWidget argument is <code>null</code>. Not that this is
+   * a great thing, but it works in the add(Widget) case so...
+   */
+  public void testAddNullAsIsWidget() {
+    CaptionPanel panel = createEmptyCaptionPanel();
+    // IsWidget reference to call the overloaded version
+    IsWidget widget = null;
+    
+    panel.add(widget);
+    // ta da...
+  }
+
   public void testHasWidgets() {
     WidgetAdder adder = new HasWidgetsTester.DefaultWidgetAdder();
 
     // With no caption.
-    HasWidgetsTester.testAll(new CaptionPanel(), adder, false);
+    HasWidgetsTester.testAll(createEmptyCaptionPanel(), adder, false);
 
     // With a text caption.
     HasWidgetsTester.testAll(new CaptionPanel("some text"), adder, false);
@@ -75,45 +102,47 @@
     }
   }
 
-// TODO(bruce): re-active when we ensure that assertions are enabled during unit test runs
-//  /**
-//   * When the caption is null, it needs to be actually removed from the DOM (to
-//   * compensate for browser bugs). This formulation requires no widget to have
-//   * been set first.
-//   */
-//  public void testCaptionAssertsAgainstNull() {
-//    // Ctor.
-//    {
-//      try {
-//        new CaptionPanel(null);
-//        fail("Should've asserted!");
-//      } catch (AssertionError e) {
-//        // good to make it here
-//      }
-//    }
-//
-//    // Setter/HTML.
-//    {
-//      try {
-//        CaptionPanel panel = new CaptionPanel("stuff");
-//        panel.setCaptionHTML(null);
-//        fail("Should've asserted!");
-//      } catch (AssertionError e) {
-//        // good to make it here
-//      }
-//    }
-//
-//    // Setter/Text.
-//    {
-//      try {
-//        CaptionPanel panel = new CaptionPanel("stuff");
-//        panel.setCaptionText(null);
-//        fail("Should've asserted!");
-//      } catch (AssertionError e) {
-//        // good to make it here
-//      }
-//    }
-//  }
+  // TODO(bruce): re-active when we ensure that assertions are enabled during
+  // unit test runs
+  // /**
+  // * When the caption is null, it needs to be actually removed from the DOM
+  // (to
+  // * compensate for browser bugs). This formulation requires no widget to have
+  // * been set first.
+  // */
+  // public void testCaptionAssertsAgainstNull() {
+  // // Ctor.
+  // {
+  // try {
+  // new CaptionPanel(null);
+  // fail("Should've asserted!");
+  // } catch (AssertionError e) {
+  // // good to make it here
+  // }
+  // }
+  //
+  // // Setter/HTML.
+  // {
+  // try {
+  // CaptionPanel panel = new CaptionPanel("stuff");
+  // panel.setCaptionHTML(null);
+  // fail("Should've asserted!");
+  // } catch (AssertionError e) {
+  // // good to make it here
+  // }
+  // }
+  //
+  // // Setter/Text.
+  // {
+  // try {
+  // CaptionPanel panel = new CaptionPanel("stuff");
+  // panel.setCaptionText(null);
+  // fail("Should've asserted!");
+  // } catch (AssertionError e) {
+  // // good to make it here
+  // }
+  // }
+  // }
 
   public void testCtorAsHtmlFlag() {
     String s = "this is <b>not</b> null";
@@ -152,7 +181,7 @@
   }
 
   public void testDefaultCaptionIsEmptyString() {
-    CaptionPanel panel = new CaptionPanel();
+    CaptionPanel panel = createEmptyCaptionPanel();
     assertEquals("", panel.getCaptionText());
     assertEquals("", panel.getCaptionHTML());
     // Wigets may be supported in the future.
@@ -161,7 +190,7 @@
   }
 
   public void testGetSetHTMLCaption() {
-    CaptionPanel panel = new CaptionPanel();
+    CaptionPanel panel = createEmptyCaptionPanel();
     panel.setCaptionHTML("<b>bold</b>");
     assertEqualsIgnoreCase("<b>bold</b>", panel.getCaptionHTML());
     assertEquals("bold", panel.getCaptionText());
@@ -169,7 +198,7 @@
 
   public void testGetSetTextCaption() {
     String s = "this is <b>not</b> null";
-    CaptionPanel panel = new CaptionPanel();
+    CaptionPanel panel = createEmptyCaptionPanel();
     panel.setCaptionText(s);
     assertEquals(s, panel.getCaptionText());
     assertNotEquals(s, panel.getCaptionHTML());
@@ -297,14 +326,18 @@
 
   public void testSafeHtmlConstructor() {
     CaptionPanel panel = new CaptionPanel(SafeHtmlUtils.fromSafeConstant(html));
-    
+
     assertEquals(html, panel.getCaptionHTML().toLowerCase());
   }
 
   public void testSetCaptionSafeHtml() {
     CaptionPanel panel = new CaptionPanel("hiworld");
     panel.setCaptionHTML(SafeHtmlUtils.fromSafeConstant(html));
-    
+
     assertEquals(html, panel.getCaptionHTML().toLowerCase());
   }
+
+  private CaptionPanel createEmptyCaptionPanel() {
+    return new CaptionPanel();
+  }
 }

diff --git a/user/test/com/google/gwt/user/client/ui/DisclosurePanelTest.java b/user/test/com/google/gwt/user/client/ui/DisclosurePanelTest.java
index 106ec14..aac9f35 100644
--- a/user/test/com/google/gwt/user/client/ui/DisclosurePanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/DisclosurePanelTest.java

@@ -61,6 +61,32 @@
     };
     t.schedule(450);
   }
+  
+  /**
+   * Tests {@link DisclosurePanel#add(IsWidget)}.
+   */
+  public void testAddAsIsWidget() {
+    DisclosurePanel panel = createEmptyDisclourePanel();
+    Widget widget = new Label("foo");
+
+    // IsWidget cast to call the overloaded version
+    panel.add((IsWidget) widget);
+
+    assertSame(widget, panel.getContent());
+  }
+
+  /**
+   * Ensures that {@link DisclosurePanel#add(IsWidget)} does <b>NOT</b> throws a
+   * {@link NullPointerException} when the IsWidget argument is
+   * <code>null</code>. Stupid, but it's what add(Widget) does.
+   */
+  public void testAddNullAsIsWidget() {
+    DisclosurePanel panel = createEmptyDisclourePanel();
+    IsWidget widget = null;
+    
+    panel.add(widget);
+    // ta da...
+  }
 
   public void testAttachDetachOrder() {
     HasWidgetsTester.testAll(new DisclosurePanel(),
@@ -82,20 +108,21 @@
 
   public void testEvents() {
     final DisclosurePanel panel = createTestPanel();
-    assertEquals(1, panel.getHandlerManager().getHandlerCount(CloseEvent.getType()));
+    assertEquals(1,
+        panel.getHandlerManager().getHandlerCount(CloseEvent.getType()));
     panel.addCloseHandler(new CloseHandler<DisclosurePanel>() {
 
       public void onClose(CloseEvent<DisclosurePanel> event) {
         // for now nothing.
       }
     });
-    assertEquals(2, panel.getHandlerManager().getHandlerCount(CloseEvent.getType()));
+    assertEquals(2,
+        panel.getHandlerManager().getHandlerCount(CloseEvent.getType()));
   }
 
   /**
    * Test to ensure that event handler dispatch function appropriately.
    */
-  @SuppressWarnings("deprecation")
   public void testEventHandlers() {
 
     final boolean[] aDidFire = new boolean[2];
@@ -127,8 +154,10 @@
     panel.addEventHandler(handleA);
     panel.addEventHandler(handleB);
     // There is one to begin with.
-    assertEquals(3, panel.getHandlerManager().getHandlerCount(CloseEvent.getType()));
-    assertEquals(3, panel.getHandlerManager().getHandlerCount(OpenEvent.getType()));
+    assertEquals(3,
+        panel.getHandlerManager().getHandlerCount(CloseEvent.getType()));
+    assertEquals(3,
+        panel.getHandlerManager().getHandlerCount(OpenEvent.getType()));
 
     panel.setOpen(true);
     // We expect onOpen to fire and onClose to not fire.
@@ -145,8 +174,10 @@
     aDidFire[OPEN] = bDidFire[CLOSE] = false;
 
     panel.removeEventHandler(handleB);
-    assertEquals(2, panel.getHandlerManager().getHandlerCount(OpenEvent.getType()));
-    assertEquals(2, panel.getHandlerManager().getHandlerCount(CloseEvent.getType()));
+    assertEquals(2,
+        panel.getHandlerManager().getHandlerCount(OpenEvent.getType()));
+    assertEquals(2,
+        panel.getHandlerManager().getHandlerCount(CloseEvent.getType()));
 
     panel.setOpen(true);
     panel.setOpen(false);
@@ -169,6 +200,39 @@
     content.removeFromParent();
     assertNull(panel.getContent());
   }
+  
+  /**
+   * Tests {@link DisclosurePanel#remove(IsWidget)}.
+   */
+  public void testRemoveAsIsWidget() {
+    DisclosurePanel panel = createEmptyDisclourePanel();
+    Widget widget = new Label("foo");
+    panel.setContent(widget);
+    assertSame(widget,panel.getContent());
+    
+    boolean wasPresent = panel.remove((IsWidget) widget);
+    
+    assertTrue(wasPresent);
+    assertNull(panel.getContent());
+  }
+  
+  /**
+   * Ensures that {@link DisclosurePanel#remove(IsWidget)} does <b>NOT</b> throws a
+   * {@link NullPointerException} when the IsWidget argument is
+   * <code>null</code>, for consistency with remove(Widget) brain damage.
+   */
+  public void testRemoveNullAsIsWidget() {
+    DisclosurePanel panel = createEmptyDisclourePanel();
+    // IsWidget reference to call the overload version
+    IsWidget widget = null;
+    
+    panel.remove(widget);
+    // ta da...
+  }
+
+  private DisclosurePanel createEmptyDisclourePanel() {
+    return new DisclosurePanel();
+  }
 
   private DisclosurePanel createTestPanel() {
     DisclosurePanel panel = new DisclosurePanel("Test Subject", false);

diff --git a/user/test/com/google/gwt/user/client/ui/DockLayoutPanelTest.java b/user/test/com/google/gwt/user/client/ui/DockLayoutPanelTest.java
index d53e7db..a751b7a 100644
--- a/user/test/com/google/gwt/user/client/ui/DockLayoutPanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/DockLayoutPanelTest.java

@@ -1,12 +1,12 @@
 /*
  * Copyright 2010 Google Inc.
- *
+ * 
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
  * use this file except in compliance with the License. You may obtain a copy of
  * the License at
- *
+ * 
  * http://www.apache.org/licenses/LICENSE-2.0
- *
+ * 
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
@@ -25,10 +25,9 @@
 
   public void testGetResolvedDirection() {
     DockLayoutPanel panel = createDockLayoutPanel();
-    assertEquals(
-        Direction.WEST, panel.getResolvedDirection(Direction.LINE_START));
-    assertEquals(
-        Direction.EAST, panel.getResolvedDirection(Direction.LINE_END));
+    assertEquals(Direction.WEST,
+        panel.getResolvedDirection(Direction.LINE_START));
+    assertEquals(Direction.EAST, panel.getResolvedDirection(Direction.LINE_END));
   }
 
   public void testAddLineEnd() {
@@ -45,6 +44,122 @@
     assertEquals(Direction.LINE_START, panel.getWidgetDirection(widget));
   }
 
+  /**
+   * Tests {@link DockLayoutPanel#addEast(Widget, double)}.
+   */
+  public void testAddEast() {
+    DockLayoutPanel panel = createDockLayoutPanel();
+    Widget widget = new Label();
+
+    panel.addEast(widget, 10);
+
+    assertWidgetDirection(panel, widget, Direction.EAST);
+    assertLogicalPaternity(panel, widget);
+    assertPhysicalPaternity(panel, widget);
+  }
+
+  /**
+   * Tests {@link DockLayoutPanel#addEast(IsWidget, double)}.
+   */
+  public void testAddEastAsIsWidget() {
+    DockLayoutPanel panel = createDockLayoutPanel();
+    Widget widget = new Label();
+
+    // IsWidget cast to call the overloaded version
+    panel.addEast((IsWidget) widget, 10);
+
+    assertWidgetDirection(panel, widget, Direction.EAST);
+    assertLogicalPaternity(panel, widget);
+    assertPhysicalPaternity(panel, widget);
+  }
+
+  /**
+   * Tests {@link DockLayoutPanel#addNorth(Widget, double)}.
+   */
+  public void testAddNorth() {
+    DockLayoutPanel panel = createDockLayoutPanel();
+    Widget widget = new Label();
+
+    panel.addNorth(widget, 10);
+
+    assertWidgetDirection(panel, widget, Direction.NORTH);
+    assertLogicalPaternity(panel, widget);
+    assertPhysicalPaternity(panel, widget);
+  }
+
+  /**
+   * Tests {@link DockLayoutPanel#addNorth(IsWidget, double)}.
+   */
+  public void testAddNorthAsIsWidget() {
+    DockLayoutPanel panel = createDockLayoutPanel();
+    Widget widget = new Label();
+
+    // IsWidget cast to call the overloaded version
+    panel.addNorth((IsWidget) widget, 10);
+
+    assertWidgetDirection(panel, widget, Direction.NORTH);
+    assertLogicalPaternity(panel, widget);
+    assertPhysicalPaternity(panel, widget);
+  }
+
+  /**
+   * Tests {@link DockLayoutPanel#addSouth(Widget, double)}.
+   */
+  public void testAddSouth() {
+    DockLayoutPanel panel = createDockLayoutPanel();
+    Widget widget = new Label();
+
+    panel.addSouth(widget, 10);
+
+    assertWidgetDirection(panel, widget, Direction.SOUTH);
+    assertLogicalPaternity(panel, widget);
+    assertPhysicalPaternity(panel, widget);
+  }
+
+  /**
+   * Tests {@link DockLayoutPanel#addSouth(IsWidget, double)}.
+   */
+  public void testAddSouthAsIsWidget() {
+    DockLayoutPanel panel = createDockLayoutPanel();
+    Widget widget = new Label();
+
+    // IsWidget cast to call the overloaded version
+    panel.addSouth((IsWidget) widget, 10);
+
+    assertWidgetDirection(panel, widget, Direction.SOUTH);
+    assertLogicalPaternity(panel, widget);
+    assertPhysicalPaternity(panel, widget);
+  }
+
+  /**
+   * Tests {@link DockLayoutPanel#addWest(Widget, double)}.
+   */
+  public void testAddWest() {
+    DockLayoutPanel panel = createDockLayoutPanel();
+    Widget widget = new Label();
+
+    panel.addWest(widget, 10);
+
+    assertWidgetDirection(panel, widget, Direction.WEST);
+    assertLogicalPaternity(panel, widget);
+    assertPhysicalPaternity(panel, widget);
+  }
+
+  /**
+   * Tests {@link DockLayoutPanel#addWest(IsWidget, double)}.
+   */
+  public void testAddWestAsIsWidget() {
+    DockLayoutPanel panel = createDockLayoutPanel();
+    Widget widget = new Label();
+
+    // IsWidget cast to call the overloaded version
+    panel.addWest((IsWidget) widget, 10);
+
+    assertWidgetDirection(panel, widget, Direction.WEST);
+    assertLogicalPaternity(panel, widget);
+    assertPhysicalPaternity(panel, widget);
+  }
+
   public void testInsertLineEnd() {
     DockLayoutPanel panel = createDockLayoutPanel();
     Widget widget = new Label();
@@ -62,4 +177,52 @@
   protected DockLayoutPanel createDockLayoutPanel() {
     return new DockLayoutPanel(Unit.PX);
   }
+
+  /**
+   * Asserts that <b>panel</b> is the logical parent of <b>expectedChild</b>.
+   * 
+   * @param panel the parent panel
+   * @param expectedChild the expected child of <b>panel</b>
+   */
+  private void assertLogicalPaternity(ComplexPanel panel, Widget expectedChild) {
+    assertSame("The parent and the panel must be the same", panel,
+        expectedChild.getParent());
+    assertTrue("The child must be in the childen collection of the panel",
+        panel.getChildren().contains(expectedChild));
+  }
+
+  /**
+   * Asserts that <b>expectedFirstChild</b> is the first physical child of
+   * <b>panel</b>.
+   * 
+   * @param panel the parent panel
+   * @param expectedFirstChild the expected first child of <b>panel</b>
+   */
+  private void assertPhysicalPaternity(DockLayoutPanel panel,
+      Widget expectedFirstChild) {
+    assertSame(
+        "The parent's Element of the child must be the panel's container Element",
+        expectedFirstChild.getElement().getParentElement(),
+        panel.getWidgetContainerElement(expectedFirstChild));
+    assertSame(
+        "The child's Element must be first child of the panel's container Element",
+        panel.getWidgetContainerElement(expectedFirstChild).getFirstChildElement(),
+        expectedFirstChild.getElement());
+  }
+
+  /**
+   * Asserts that the {@link DockLayoutPanel.Direction} of <b>widget</b> in
+   * <b>panel</b> is <b>expectedDirection</b>.
+   * 
+   * @param panel the panel containing <b>widget</b>
+   * @param widget the widget being tested
+   * @param expectedDirection the expected direction
+   */
+  private void assertWidgetDirection(DockLayoutPanel panel, Widget widget,
+      DockLayoutPanel.Direction expectedDirection) {
+    assertEquals("The direction of the widget in the panel should be "
+        + expectedDirection, expectedDirection,
+        panel.getWidgetDirection(widget));
+  }
+
 }

diff --git a/user/test/com/google/gwt/user/client/ui/DockPanelTest.java b/user/test/com/google/gwt/user/client/ui/DockPanelTest.java
index 85bf22b..b271f60 100644
--- a/user/test/com/google/gwt/user/client/ui/DockPanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/DockPanelTest.java

@@ -22,6 +22,7 @@
 /**
  * Tests the DockPanel widget.
  */
+@SuppressWarnings("deprecation")
 public class DockPanelTest extends GWTTestCase {
 
   static class Adder implements HasWidgetsTester.WidgetAdder {
@@ -113,6 +114,16 @@
     assertTrue(((DockPanel.LayoutData) l4.getLayoutData()).direction == DockPanel.NORTH);
   }
 
+  public void testAddAsIsWidget() {
+    DockPanel panel = createDockPanel();
+    Widget widget = new Label("foo");
+    
+    panel.add(widget, DockPanel.NORTH);
+    
+    assertLogicalPaternity(panel,widget);
+    assertPhysicalPaternity(panel,widget);
+  }
+  
   public void testAttachDetachOrder() {
     HasWidgetsTester.testAll(new DockPanel(), new Adder(), true);
   }
@@ -160,4 +171,35 @@
     UIObjectTest.assertDebugId("myDock-center",
         DOM.getParent(center.getElement()));
   }
+
+  /**
+   * Asserts that <b>panel</b> is the logical parent of <b>expectedChild</b>.
+   * 
+   * @param panel the parent panel
+   * @param expectedChild the expected child of <b>panel</b>
+   */
+  private void assertLogicalPaternity(DockPanel panel, Widget expectedChild) {
+    assertSame("The parent and the panel must be the same", panel,
+        expectedChild.getParent());
+    assertTrue("The child must be in the childen collection of the panel",
+        panel.getChildren().contains(expectedChild));
+  }
+  
+  /**
+   * Asserts that <b>expectedChild</b> is the first physical child of
+   * <b>parent</b>.
+   * 
+   * @param parent the parent panel
+   * @param expectedChild the expected child of <b>panel</b>
+   */
+  private void assertPhysicalPaternity(Widget parent,
+      Widget expectedChild) {
+    Element panelElement = parent.getElement();
+    Element childElement = expectedChild.getElement();
+    assertTrue("The parent's Element of the child must be the panel's Element", DOM.isOrHasChild(panelElement, childElement));
+  }
+
+  private DockPanel createDockPanel() {
+    return new DockPanel();
+  }
 }

diff --git a/user/test/com/google/gwt/user/client/ui/HTMLPanelTest.java b/user/test/com/google/gwt/user/client/ui/HTMLPanelTest.java
index 94f63ae..6df56dc 100644
--- a/user/test/com/google/gwt/user/client/ui/HTMLPanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/HTMLPanelTest.java

@@ -1,12 +1,12 @@
 /*
  * Copyright 2008 Google Inc.
- *
+ * 
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
  * use this file except in compliance with the License. You may obtain a copy of
  * the License at
- *
+ * 
  * http://www.apache.org/licenses/LICENSE-2.0
- *
+ * 
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
@@ -79,10 +79,11 @@
    */
   public void testAddToElement() {
     Label labelA = new Label("A"), labelB = new Label("B");
-    HTMLPanel p = new HTMLPanel("<div class=\"a\"></div><div class=\"b\"></div>");
+    HTMLPanel p = new HTMLPanel(
+        "<div class=\"a\"></div><div class=\"b\"></div>");
     Element first = p.getElement().getFirstChildElement();
     Element second = first.getNextSiblingElement();
-    
+
     p.add(labelA, first);
     p.add(labelB, second);
     // Ensure that both Label's have the correct parent.
@@ -92,10 +93,10 @@
 
   /**
    * This is meant to catch an issue created by a faulty optimization. To
-   * optimize add() when the HTMLPanel is unattached, we would originally
-   * move its element to a hidden div so that getElementById() would work.
-   * Unfortunately, we didn't move it back to its original parent, causing
-   * a problem in the case described in this test.
+   * optimize add() when the HTMLPanel is unattached, we would originally move
+   * its element to a hidden div so that getElementById() would work.
+   * Unfortunately, we didn't move it back to its original parent, causing a
+   * problem in the case described in this test.
    */
   public void testAddPartiallyAttached() {
     SimplePanel sp = new SimplePanel();
@@ -145,68 +146,108 @@
   }
 
   /**
-   * Ensures that addAndReplaceChild() puts the widget in exactly the right place in the DOM.
+   * Ensures that {@link HTMLPanel#addAndReplaceChild(Widget,String)} puts the
+   * widget in exactly the right place in the DOM.
    */
   public void testAddAndReplaceElement() {
-    HTMLPanel hp = new HTMLPanel("<div id='parent'>foo<span id='placeholder'></span>bar</div>");
-
+    HTMLPanel hp = new HTMLPanel(
+        "<div id='parent'>foo<span id='placeholder'></span>bar</div>");
     Button button = new Button("my button");
+
     hp.addAndReplaceElement(button, "placeholder");
 
-    assertEquals("parent", button.getElement().getParentElement().getId());
-
-    Node prev = button.getElement().getPreviousSibling();
-    assertEquals("foo", prev.getNodeValue());
-
-    Node next = button.getElement().getNextSibling();
-    assertEquals("bar", next.getNodeValue());
+    assertParentId(button, "parent");
+    assertIsBetweenSiblings(button, "foo", "bar");
   }
 
   /**
-   * Ensures that addAndReplaceChild() puts the widget in exactly the right place in the DOM.
+   * Ensures that
+   * {@link HTMLPanel#addAndReplaceElement(Widget, com.google.gwt.user.client.Element)}
+   * puts the widget in exactly the right place in the DOM.
    */
   @SuppressWarnings("deprecation")
   public void testAddAndReplaceElementForUserElement() {
-
-    HTMLPanel hp = new HTMLPanel("<div id='parent'>foo<span id='placeholder'></span>bar</div>");
-
+    HTMLPanel hp = new HTMLPanel(
+        "<div id='parent'>foo<span id='placeholder'></span>bar</div>");
     RootPanel.get().add(hp);
     com.google.gwt.user.client.Element placeholder = hp.getElementById("placeholder");
-
     Button button = new Button("my button");
+
     hp.addAndReplaceElement(button, placeholder);
 
-    assertEquals("parent", button.getElement().getParentElement().getId());
-
-    Node prev = button.getElement().getPreviousSibling();
-    assertEquals("foo", prev.getNodeValue());
-
-    Node next = button.getElement().getNextSibling();
-    assertEquals("bar", next.getNodeValue());
+    assertParentId(button, "parent");
+    assertIsBetweenSiblings(button, "foo", "bar");
   }
 
   /**
-   * Ensures that addAndReplaceChild() puts the widget in exactly the right place in the DOM.
+   * Ensures that overloaded version of
+   * {@link HTMLPanel#addAndReplaceElement(IsWidget, com.google.gwt.user.client.Element)}
+   * for IsWidget puts the widget in exactly the right place in the DOM.
    */
-  public void testAddAndReplaceElementForElement() {
-    HTMLPanel hp = new HTMLPanel("<div id='parent'>foo<span id='placeholder'></span>bar</div>");
-
+  public void testAddAndReplaceElementForUserElementAsIsWidget() {
+    HTMLPanel hp = new HTMLPanel(
+        "<div id='parent'>foo<span id='placeholder'></span>bar</div>");
     RootPanel.get().add(hp);
-    Element placeholder = hp.getElementById("placeholder");
-
+    com.google.gwt.user.client.Element placeholder = hp.getElementById("placeholder");
     Button button = new Button("my button");
-    hp.addAndReplaceElement(button, placeholder);
+    // IsWidget reference to call the overloaded version
+    IsWidget isWidget = button;
 
-    assertEquals("parent", button.getElement().getParentElement().getId());
+    hp.addAndReplaceElement(isWidget, placeholder);
 
-    Node prev = button.getElement().getPreviousSibling();
-    assertEquals("foo", prev.getNodeValue());
-
-    Node next = button.getElement().getNextSibling();
-    assertEquals("bar", next.getNodeValue());
+    assertParentId(button, "parent");
+    assertIsBetweenSiblings(button, "foo", "bar");
   }
 
   /**
+   * Ensures that {@link HTMLPanel#addAndReplaceElement(Widget, Element)} puts
+   * the widget in exactly the right place in the DOM.
+   */
+  public void testAddAndReplaceElementForElement() {
+    HTMLPanel hp = new HTMLPanel(
+        "<div id='parent'>foo<span id='placeholder'></span>bar</div>");
+    RootPanel.get().add(hp);
+    Element placeholder = hp.getElementById("placeholder");
+    Button button = new Button("my button");
+
+    hp.addAndReplaceElement(button, placeholder);
+
+    assertParentId(button, "parent");
+    assertIsBetweenSiblings(button, "foo", "bar");
+  }
+
+  /**
+   * Tests {@link HTMLPanel#addAndReplaceElement(Widget, String)}.
+   */
+  public void testAddAndReplaceElementById() {
+    HTMLPanel hp = new HTMLPanel(
+        "<div id='parent'>foo<span id='placeholder'></span>bar</div>");
+    RootPanel.get().add(hp);
+    Button button = new Button("my button");
+
+    hp.addAndReplaceElement(button, "placeholder");
+
+    assertParentId(button, "parent");
+    assertIsBetweenSiblings(button, "foo", "bar");
+  }
+  
+  /**
+   * Tests {@link HTMLPanel#addAndReplaceElement(IsWidget, String)}.
+   */
+  public void testAddAndReplaceElementByIdAsIsWidget() {
+    HTMLPanel hp = new HTMLPanel(
+        "<div id='parent'>foo<span id='placeholder'></span>bar</div>");
+    RootPanel.get().add(hp);
+    Button button = new Button("my button");
+
+    // IsWidget cast to call the overloaded version
+    hp.addAndReplaceElement((IsWidget) button, "placeholder");
+
+    assertParentId(button, "parent");
+    assertIsBetweenSiblings(button, "foo", "bar");
+  }
+  
+  /**
    * Tests table root tag.
    */
   public void testCustomRootTagAsTable() {
@@ -274,7 +315,7 @@
   public void testSafeHtml() {
     TestTemplates templates = GWT.create(TestTemplates.class);
     SafeHtml table = templates.tableTemplate("Hello");
-    
+
     HTMLPanel hp = new HTMLPanel(table);
     InlineLabel label = new InlineLabel("World");
     hp.addAndReplaceElement(label, "labelHere");
@@ -296,4 +337,30 @@
     assertEquals("div", parent.getTagName().toLowerCase());
     assertEquals("table", firstChild.getTagName().toLowerCase());
   }
+
+  /**
+   * Asserts that the widget w is between the given previous and next nodes.
+   * 
+   * @param w the widget
+   * @param previous the expected previous node string representation of the
+   *          widget
+   * @param next the expected next node string representation of the widget
+   */
+  private void assertIsBetweenSiblings(Widget w, String previous, String next) {
+    Node prevNode = w.getElement().getPreviousSibling();
+    assertEquals(previous, prevNode.getNodeValue());
+
+    Node nextNode = w.getElement().getNextSibling();
+    assertEquals(next, nextNode.getNodeValue());
+  }
+
+  /**
+   * Asserts that the parent id of the widget is the given one.
+   * 
+   * @param w the widget
+   * @param expected the expected parent id of w
+   */
+  private void assertParentId(Widget w, String expected) {
+    assertEquals(expected, w.getElement().getParentElement().getId());
+  }
 }

diff --git a/user/test/com/google/gwt/user/client/ui/HTMLTableTestBase.java b/user/test/com/google/gwt/user/client/ui/HTMLTableTestBase.java
index ef021e8..ce44b5a 100644
--- a/user/test/com/google/gwt/user/client/ui/HTMLTableTestBase.java
+++ b/user/test/com/google/gwt/user/client/ui/HTMLTableTestBase.java

@@ -229,6 +229,47 @@
     assertEquals(columnGroup, formatter.columnGroup);
   }
 
+  /**
+   * Tests {@link HTMLTable#setWidget(int, int, Widget)}.
+   */
+  public void testSetWidget() {
+    HTMLTable t = getTable(2, 2);
+    Widget widget = new Label("foo");
+
+    t.setWidget(1, 1, widget);
+
+    assertLogicalPaternity(t, widget);
+    assertPhysicalPaternityInPosition(t, widget, 1, 1);
+  }
+
+  /**
+   * Tests {@link HTMLTable#setWidget(int, int, IsWidget)}.
+   */
+  public void testSetWidgetAsIsWidget() {
+    HTMLTable t = getTable(2, 2);
+    Widget widget = new Label("foo");
+
+    // IsWidget cast to call the overloaded version
+    t.setWidget(1, 1, (IsWidget) widget);
+
+    assertLogicalPaternity(t, widget);
+    assertPhysicalPaternityInPosition(t, widget, 1, 1);
+  }
+
+  /**
+   * Ensures that {@link HTMLTable#setWidget(int, int, IsWidget)} does
+   * <b>NOT</b> throws a {@link NullPointerException} when the Widget argument
+   * is <code>null</code>, for compatibility with setWidget(Widget) foolishness
+   */
+  public void testSetNullWidgetAsIsWidget() {
+    HTMLTable t = getTable(2, 2);
+    // IsWidget reference to call the overloaded version
+    IsWidget widget = null;
+
+    t.setWidget(1, 1, widget);
+    // ta da...
+  }
+
   public void testSettingCellAttributes() {
     // These tests simple test for errors while setting these fields. The
     // Patient sample under the survey project has the visual part of the test.
@@ -292,4 +333,16 @@
     t.getRowFormatter().setStyleName(3, "newStyle");
     assertEquals("newStyle", t.getRowFormatter().getStyleName(3));
   }
+
+  private void assertPhysicalPaternityInPosition(HTMLTable parent,
+      Widget child, int row, int column) {
+    assertSame("The child should be in te given position", child,
+        parent.getWidget(row, column));
+  }
+
+  private void assertLogicalPaternity(HTMLTable parent, Widget child) {
+    Iterator<Widget> iterator = parent.iterator();
+    assertTrue(iterator.hasNext());
+    assertSame(child, iterator.next());
+  }
 }

diff --git a/user/test/com/google/gwt/user/client/ui/LayoutPanelTest.java b/user/test/com/google/gwt/user/client/ui/LayoutPanelTest.java
index 6ac4e96..a8e63ce 100644
--- a/user/test/com/google/gwt/user/client/ui/LayoutPanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/LayoutPanelTest.java

@@ -15,12 +15,15 @@
  */
 package com.google.gwt.user.client.ui;
 
+import com.google.gwt.core.client.Scheduler;
+import com.google.gwt.core.client.Scheduler.ScheduledCommand;
 import com.google.gwt.dom.client.Document;
 import com.google.gwt.dom.client.Style.Unit;
+import com.google.gwt.layout.client.LayerFriend;
+import com.google.gwt.layout.client.Layout;
 import com.google.gwt.layout.client.Layout.AnimationCallback;
 import com.google.gwt.layout.client.Layout.Layer;
 import com.google.gwt.user.client.Command;
-import com.google.gwt.user.client.DeferredCommand;
 
 /**
  * Tests for {@link LayoutPanel}. Note that this only tests LayoutPanel-specific
@@ -33,6 +36,7 @@
    * Tests for a bug in LayoutCommand, which caused an animate() call, just
    * before an unnecessary forceLayout(), to get stuck. See issue 4360.
    */
+  @SuppressWarnings("deprecation")
   public void testRedundantForceLayout() {
     final LayoutPanel p = new LayoutPanel();
     Label l = new Label("foo");
@@ -42,7 +46,8 @@
     p.forceLayout();
 
     delayTestFinish(5000);
-    DeferredCommand.addCommand(new Command() {
+    // Fully qualified to avoid the deprecation warning in the import section
+    com.google.gwt.user.client.DeferredCommand.addCommand(new Command() {
       public void execute() {
         p.animate(100, new AnimationCallback() {
           public void onLayout(Layer layer, double progress) {
@@ -62,6 +67,7 @@
    * cropped up on IE7 as a result of CSS expressions used in PopupImplIE6, as
    * described in issue 4532.
    */
+  @SuppressWarnings("deprecation")
   public void testWeirdPopupInteraction() {
     assertTrue(Document.get().isCSS1Compat());
 
@@ -73,7 +79,8 @@
     popup.center();
 
     delayTestFinish(2000);
-    DeferredCommand.addCommand(new Command() {
+    // Fully qualified to avoid the deprecation warning in the import section
+    com.google.gwt.user.client.DeferredCommand.addCommand(new Command() {
       public void execute() {
         int offsetWidth = lp.getOffsetWidth();
         int offsetHeight = lp.getOffsetHeight();
@@ -83,4 +90,415 @@
       }
     });
   }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetBottomHeight(Widget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetBottomHeight() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    layoutPanel.setWidgetBottomHeight(label, 1.5, Unit.EM, 2.0, Unit.EM);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().bottom(1.5).bottomUnit(Unit.EM).height(2.0).heightUnit(
+            Unit.EM));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetBottomHeight(IsWidget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetBottomHeightAsIsWidget() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    // IsWidget cast to call the overloaded version
+    layoutPanel.setWidgetBottomHeight((IsWidget) label, 10.0, Unit.PX, 15.0,
+        Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().bottom(10.0).bottomUnit(Unit.PX).height(15.0).heightUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetLeftRight(Widget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetLeftRight() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    layoutPanel.setWidgetLeftRight(label, 10.0, Unit.PX, 20.0, Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().left(10.0).leftUnit(Unit.PX).right(20.0).rightUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetLeftRight(IsWidget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetLeftRightAsIsWidget() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    // IsWidget cast to call the overloaded version
+    layoutPanel.setWidgetLeftRight((IsWidget) label, 10.0, Unit.PX, 15.0,
+        Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().left(10.0).leftUnit(Unit.PX).right(15.0).rightUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetLeftWidth(Widget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetLeftWidth() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    layoutPanel.setWidgetLeftWidth(label, 10.0, Unit.PX, 20.0, Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().left(10.0).leftUnit(Unit.PX).width(20.0).widthUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetLeftWidth(IsWidget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetLeftWidthAsIsWidget() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    // IsWidget cast to call the overloaded version
+    layoutPanel.setWidgetLeftWidth((IsWidget) label, 10.0, Unit.PX, 15.0,
+        Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().left(10.0).leftUnit(Unit.PX).width(15.0).widthUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetRightWidth(Widget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetRightWidth() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    layoutPanel.setWidgetRightWidth(label, 10.0, Unit.PX, 20.0, Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().right(10.0).rightUnit(Unit.PX).width(20.0).widthUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetRightWidth(IsWidget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetRightWidthAsIsWidget() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    // IsWidget cast to call the overloaded version
+    layoutPanel.setWidgetRightWidth((IsWidget) label, 10.0, Unit.PX, 15.0,
+        Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().right(10.0).rightUnit(Unit.PX).width(15.0).widthUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetTopBottom(Widget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetTopBottom() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    layoutPanel.setWidgetTopBottom(label, 10.0, Unit.PX, 20.0, Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().top(10.0).topUnit(Unit.PX).bottom(20.0).bottomUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetTopBottom(IsWidget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetTopBottomAsIsWidget() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    // IsWidget cast to call the overloaded version
+    layoutPanel.setWidgetTopBottom((IsWidget) label, 10.0, Unit.PX, 15.0,
+        Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().top(10.0).topUnit(Unit.PX).bottom(15.0).bottomUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetTopHeight(Widget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetTopHeight() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    layoutPanel.setWidgetTopHeight(label, 10.0, Unit.PX, 20.0, Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().top(10.0).topUnit(Unit.PX).height(20.0).heightUnit(
+            Unit.PX));
+  }
+
+  /**
+   * Tests
+   * {@link LayoutPanel#setWidgetTopHeight(IsWidget, double, Unit, double, Unit)}
+   * .
+   */
+  public void testSetWidgetTopHeightAsIsWidget() {
+    LayoutPanel layoutPanel = createLayoutPanel();
+    Widget label = createLabelInPanel(layoutPanel);
+
+    // IsWidget cast to call the overloaded version
+    layoutPanel.setWidgetTopHeight((IsWidget) label, 10.0, Unit.PX, 15.0,
+        Unit.PX);
+
+    assertLayerProperties(
+        label,
+        new LayerProperties().top(10.0).topUnit(Unit.PX).height(15.0).heightUnit(
+            Unit.PX));
+  }
+
+  protected LayoutPanel createLayoutPanel() {
+    return new LayoutPanel();
+  }
+
+  protected Widget createLabelInPanel(LayoutPanel layoutPanel) {
+    Widget label = new Label("foo");
+    layoutPanel.add(label);
+    return label;
+  }
+
+  /**
+   * <p>
+   * Parameter class that hold a set of properties of a {@link Layout.Layer}. The
+   * default value for all the six properties (top, right, bottom, left, height
+   * and width) is 0.0, value that matches the default values for this
+   * properties in the actual {@link Layout.Layer}. The default values for the
+   * units also match the default values in {@link Layout.Layer}: <br>
+   * <code>topUnit = rightUnit = bottomUnit = leftUnit = {@link Unit#PX}</code>
+   * <br>
+   * <code>heigthUnit = widthUnit = null</code>
+   * </p>
+   * This class must be used as a parameter of
+   * {@link LayoutPanelTest#assertLayerProperties(Widget, LayerProperties)}, and
+   * was thought to be used as a builder in order to improve readability and
+   * reduce errors with the parameters of
+   * {@link LayoutPanelTest#assertLayerProperties(Widget, LayerProperties)}.
+   * </p>
+   * 
+   * <p>
+   * <h3>Example:</h3>
+   * <code>assertLayerProperties(label,
+   *    new LayerProperties().bottom(10.0).bottomUnit(Unit.PX)
+   *    .height(15.0).heightUnit(Unit.PX);</code>
+   * </p>
+   */
+  static class LayerProperties {
+    private double top, right, bottom, left, height, width;
+    private Unit topUnit = Unit.PX, rightUnit = Unit.PX, bottomUnit = Unit.PX,
+        leftUnit = Unit.PX, heightUnit, widthUnit;
+
+    LayerProperties top(double top) {
+      this.top = top;
+      return this;
+    }
+
+    double getTop() {
+      return top;
+    }
+
+    LayerProperties topUnit(Unit topUnit) {
+      this.topUnit = topUnit;
+      return this;
+    }
+
+    Unit getTopUnit() {
+      return topUnit;
+    }
+
+    LayerProperties right(double right) {
+      this.right = right;
+      return this;
+    }
+
+    double getRight() {
+      return right;
+    }
+
+    LayerProperties rightUnit(Unit rightUnit) {
+      this.rightUnit = rightUnit;
+      return this;
+    }
+
+    Unit getRightUnit() {
+      return rightUnit;
+    }
+
+    LayerProperties bottom(double bottom) {
+      this.bottom = bottom;
+      return this;
+    }
+
+    double getBottom() {
+      return bottom;
+    }
+
+    LayerProperties bottomUnit(Unit bottomUnit) {
+      this.bottomUnit = bottomUnit;
+      return this;
+    }
+
+    Unit getBottomUnit() {
+      return bottomUnit;
+    }
+
+    LayerProperties left(double left) {
+      this.left = left;
+      return this;
+    }
+
+    double getLeft() {
+      return left;
+    }
+
+    LayerProperties leftUnit(Unit leftUnit) {
+      this.leftUnit = leftUnit;
+      return this;
+    }
+
+    Unit getLeftUnit() {
+      return leftUnit;
+    }
+
+    LayerProperties height(double height) {
+      this.height = height;
+      return this;
+    }
+
+    double getHeight() {
+      return height;
+    }
+
+    LayerProperties heightUnit(Unit heightUnit) {
+      this.heightUnit = heightUnit;
+      return this;
+    }
+
+    Unit getHeightUnit() {
+      return heightUnit;
+    }
+
+    LayerProperties width(double width) {
+      this.width = width;
+      return this;
+    }
+
+    double getWidth() {
+      return width;
+    }
+
+    LayerProperties widthUnit(Unit widthUnit) {
+      this.widthUnit = widthUnit;
+      return this;
+    }
+
+    Unit getWidthUnit() {
+      return widthUnit;
+    }
+  }
+  
+  /**
+   * <p>
+   * Asserts that the layer properties of the <b>widget</b> are the given ones.
+   * </p>
+   * 
+   * @param widget the widget being tested
+   * @param expectedLayerProperties the expected properties of <b>widget</b>
+   */
+  private void assertLayerProperties(final Widget widget,
+      final LayerProperties expectedLayerProperties) {
+    delayTestFinish(2000);
+    Scheduler.get().scheduleDeferred(new ScheduledCommand() {
+
+      public void execute() {
+        Layer layer = (Layout.Layer) widget.getLayoutData();
+        LayerFriend helper = new LayerFriend(layer);
+
+        assertEquals("Top", expectedLayerProperties.getTop(), helper.getTop());
+        assertEquals("Right", expectedLayerProperties.getRight(),
+            helper.getRight());
+        assertEquals("Bottom", expectedLayerProperties.getBottom(),
+            helper.getBottom());
+        assertEquals("Left", expectedLayerProperties.getLeft(),
+            helper.getLeft());
+        assertEquals("Height", expectedLayerProperties.getHeight(),
+            helper.getHeight());
+        assertEquals("Width", expectedLayerProperties.getWidth(),
+            helper.getWidth());
+
+        assertEquals("Top Units", expectedLayerProperties.getTopUnit(),
+            helper.getTopUnit());
+        assertEquals("Right Units", expectedLayerProperties.getRightUnit(),
+            helper.getRightUnit());
+        assertEquals("Bottom Units", expectedLayerProperties.getBottomUnit(),
+            helper.getBottomUnit());
+        assertEquals("Left Units", expectedLayerProperties.getLeftUnit(),
+            helper.getLeftUnit());
+        assertEquals("Height Units", expectedLayerProperties.getHeightUnit(),
+            helper.getHeightUnit());
+        assertEquals("Width Units", expectedLayerProperties.getWidthUnit(),
+            helper.getWidthUnit());
+        finishTest();
+      }
+    });
+  }
 }

diff --git a/user/test/com/google/gwt/user/client/ui/StackLayoutPanelTest.java b/user/test/com/google/gwt/user/client/ui/StackLayoutPanelTest.java
index 3cb288b..8acbeb0 100644
--- a/user/test/com/google/gwt/user/client/ui/StackLayoutPanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/StackLayoutPanelTest.java

@@ -62,12 +62,66 @@
     }
   }
 
+  /**
+   * Tests {@link StackLayoutPanel#add(Widget, String, boolean, double)}.
+   */
+  public void testAddWithTextHeader() {
+    StackLayoutPanel panel = createStackLayoutPanel(Unit.EM);
+    Widget widget = new Label("foo");
+
+    panel.add(widget, "header", false, 1);
+
+    assertLogicalPaternityOfChild(panel, widget);
+  }
+
+  /**
+   * Tests {@link StackLayoutPanel#add(IsWidget, String, boolean, double)}.
+   */
+  public void testAddWithTextHeaderAsIsWidget() {
+    StackLayoutPanel panel = createStackLayoutPanel(Unit.EM);
+    Widget widget = new Label("foo");
+
+    // IsWidget cast to call the overloaded version
+    panel.add((IsWidget) widget, "header", false, 1);
+
+    assertLogicalPaternityOfChild(panel, widget);
+  }
+
+  /**
+   * Tests {@link StackLayoutPanel#add(Widget, Widget, double)}.
+   */
+  public void testAddWithWidgetHeader() {
+    StackLayoutPanel panel = createStackLayoutPanel(Unit.EM);
+    Widget header = new Label("foo");
+    Widget widget = new Label("bar");
+
+    panel.add(widget, header, 1);
+
+    assertLogicalPaternityOfChild(panel, widget);
+    assertLogicalPaternityOfHeader(panel, widget, header);
+  }
+
+  /**
+   * Tests {@link StackLayoutPanel#add(IsWidget, IsWidget, double)}.
+   */
+  public void testAddWithWidgetHeaderAsIsWidget() {
+    StackLayoutPanel panel = createStackLayoutPanel(Unit.EM);
+    Widget header = new Label("foo");
+    Widget widget = new Label("bar");
+
+    // IsWidget casts to call the overloaded version
+    panel.add((IsWidget) widget, (IsWidget) header, 1);
+
+    assertLogicalPaternityOfChild(panel, widget);
+    assertLogicalPaternityOfHeader(panel, widget, header);
+  }
+
   public void testAddWithSafeHtml() {
     StackLayoutPanel panel = new StackLayoutPanel(Unit.EM);
     panel.add(new HTML("foo"), SafeHtmlUtils.fromSafeConstant(html), 1.0);
-    
+
     assertEquals(1, panel.getWidgetCount());
-    assertEquals(html, 
+    assertEquals(html,
         panel.getHeaderWidget(0).getElement().getInnerHTML().toLowerCase());
   }
 
@@ -123,9 +177,9 @@
   public void testInsertSafeHtml() {
     StackLayoutPanel panel = new StackLayoutPanel(Unit.EM);
     panel.insert(new HTML("foo"), SafeHtmlUtils.fromSafeConstant(html), 1.0, 0);
-    
+
     assertEquals(1, panel.getWidgetCount());
-    assertEquals(html, 
+    assertEquals(html,
         panel.getHeaderWidget(0).getElement().getInnerHTML().toLowerCase());
   }
 
@@ -227,7 +281,7 @@
     panel.add(new HTML("bar"), "foo", 1.0);
     panel.setHeaderHTML(0, SafeHtmlUtils.fromSafeConstant(html));
     Widget header = panel.getHeaderWidget(0);
-    
+
     assertEquals(html, header.getElement().getInnerHTML().toLowerCase());
   }
 
@@ -287,4 +341,35 @@
     p.showWidget(l2);
     assertEquals(l2, p.getVisibleWidget());
   }
+
+  /**
+   * Asserts that <b>widget</b> is attached to <b>panel</b> as a child in the
+   * logical representation of <b>panel</b>.
+   * 
+   * @param panel the parent panel
+   * @param child a expected child of <b>panel</b>
+   */
+  private void assertLogicalPaternityOfChild(StackLayoutPanel panel,
+      Widget child) {
+    assertTrue("The widget should be a child of the panel",
+        panel.getWidgetIndex(child) >= 0);
+  }
+
+  /**
+   * Asserts that <b>header</b> is attached to <b>panel</b> as a header of
+   * <b>widget</b> in the logical representation of <b>panel</b>.
+   * 
+   * @param panel the parent panel
+   * @param child the child whose header is being tested
+   * @param header the expected header of <b>child</b>
+   */
+  private void assertLogicalPaternityOfHeader(StackLayoutPanel panel,
+      Widget child, Widget header) {
+    assertSame("The header should be attached to the panel.", header,
+        panel.getHeaderWidget(child));
+  }
+
+  private StackLayoutPanel createStackLayoutPanel(Unit unit) {
+    return new StackLayoutPanel(unit);
+  }
 }

diff --git a/user/test/com/google/gwt/user/client/ui/TreeTest.java b/user/test/com/google/gwt/user/client/ui/TreeTest.java
index 168f747..fdbf29f 100644
--- a/user/test/com/google/gwt/user/client/ui/TreeTest.java
+++ b/user/test/com/google/gwt/user/client/ui/TreeTest.java

@@ -39,12 +39,40 @@
   public String getModuleName() {
     return "com.google.gwt.user.DebugTest";
   }
+
+  /**
+   * Test for {@link Tree#add(IsWidget)}.
+   */
+  public void testAddAsIsWidget() {
+    Tree t = createTree();
+    Widget widget = new Label("foo");
+
+    // IsWidget cast to call the overloaded version
+    t.add((IsWidget) widget);
+
+    assertEquals("The number of items should be 1", 1, t.getItemCount());
+    assertSame(widget, t.getItem(0).getWidget());
+  }
   
   /**
+   * Ensures that {@link Tree#add(Widget)} does <b>NOT</b> throws a
+   * {@link NullPointerException} when the Widget argument is <code>null</code>,
+   * for stupidity consistency with add(Widget).
+   */
+  public void testAddNullAsIsWidget() {
+    Tree t = createTree();
+    // IsWidget reference to call the overload version
+    IsWidget widget = null;
+    
+    t.add(widget);
+    // ta da...
+  }
+
+  /**
    * Test for {@link Tree#addItem(IsTreeItem)}.
    */
   public void testAddItemIsTreeItem() {
-    Tree t = new Tree();
+    Tree t = createTree();
     TreeItem item = new TreeItem("hello");
     t.addItem((IsTreeItem) item);
     assertEquals(1, t.getItemCount());
@@ -52,16 +80,16 @@
   }
 
   public void testAddItemSafeHtml() {
-    Tree t = new Tree();
+    Tree t = createTree();
     TreeItem item = t.addItem(SafeHtmlUtils.fromSafeConstant(html));
     assertEquals(html, item.getHTML().toLowerCase());
   }
-  
+
   /**
    * Test for {@link Tree#addTextItem(String)}.
    */
   public void testAddTextItem() {
-    Tree t = new Tree();
+    Tree t = createTree();
     String text = "Some<br>text";
     TreeItem item = t.addTextItem(text);
     assertEquals(text, item.getText());
@@ -71,11 +99,11 @@
   }
 
   public void testAttachDetachOrder() {
-    HasWidgetsTester.testAll(new Tree(), new Adder(), true);
+    HasWidgetsTester.testAll(createTree(), new Adder(), true);
   }
 
   public void testClear() {
-    Tree t = new Tree();
+    Tree t = createTree();
     // Adding widget to end of tree, widgets still have their parents set
     // correctly.
     TreeItem a = new TreeItem("a");
@@ -99,7 +127,7 @@
   }
 
   public void testDebugId() {
-    Tree tree = new Tree();
+    Tree tree = createTree();
     TreeItem top0 = tree.addItem("top0");
     TreeItem top1 = tree.addItem("top1");
     TreeItem top2 = tree.addItem("top2");
@@ -131,7 +159,7 @@
   }
 
   public void testInsertSameItemRepeatedly() {
-    Tree t = new Tree();
+    Tree t = createTree();
     TreeItem ti = new TreeItem();
     TreeItem wti = new TreeItem();
     wti.setWidget(new Label("label"));
@@ -145,13 +173,13 @@
   }
 
   public void testInsertItemSafeHtml() {
-    Tree t = new Tree();
+    Tree t = createTree();
     TreeItem item = t.insertItem(0, SafeHtmlUtils.fromSafeConstant(html));
     assertEquals(html, item.getHTML().toLowerCase());
   }
 
   public void testIterator() {
-    Tree tree = new Tree();
+    Tree tree = createTree();
     Iterator<TreeItem> iter = tree.treeItemIterator();
     assertFalse(iter.hasNext());
     TreeItem a = tree.addItem("a");
@@ -180,7 +208,7 @@
 
   public void testNulls() {
     // Checking for setting the widget null then clearing the tree.
-    Tree t = new Tree();
+    Tree t = createTree();
     TreeItem item = new TreeItem();
     item.setWidget(null);
     t.clear();
@@ -192,7 +220,7 @@
   }
 
   public void testRemove() {
-    Tree t = new Tree();
+    Tree t = createTree();
     TreeItem item = t.addItem("a");
     TreeItem itemb = t.addItem("b");
     t.setSelectedItem(item);
@@ -208,12 +236,12 @@
     Iterator<TreeItem> iter2 = t.treeItemIterator();
     assertFalse(iter2.hasNext());
   }
-  
+
   /**
    * Test for {@link Tree#removeItem(IsTreeItem)}.
    */
   public void testRemoveIsTreeItem() {
-    Tree t = new Tree();
+    Tree t = createTree();
     TreeItem itemA = t.addItem("a");
     TreeItem itemB = t.addItem("b");
     // initial state
@@ -227,12 +255,12 @@
     // ignore null
     t.removeItem((IsTreeItem) null);
   }
-  
+
   /**
    * Test for {@link Tree#removeItems()}.
    */
   public void testRemoveItems() {
-    Tree t = new Tree();
+    Tree t = createTree();
     TreeItem itemA = t.addItem("a");
     TreeItem itemB = t.addItem("b");
     // initial state
@@ -245,14 +273,14 @@
   }
 
   public void testRootAdd() {
-    Tree t = new Tree();
+    Tree t = createTree();
     Label l = new Label("hello");
     t.add(l);
     assertEquals(t, l.getParent());
   }
 
   public void testRootInsert() {
-    Tree t = new Tree();
+    Tree t = createTree();
     TreeItem b = t.addItem("b");
     assertEquals(1, t.getItemCount());
     assertEquals(b, t.getItem(0));
@@ -284,7 +312,7 @@
   }
 
   public void testRootInsertInvalidIndex() {
-    Tree t = new Tree();
+    Tree t = createTree();
     t.addItem("a");
     t.addItem("b");
     t.addItem("c");
@@ -307,7 +335,7 @@
   }
 
   public void testSwap() {
-    Tree t = new Tree();
+    Tree t = createTree();
 
     // Start with text.
     TreeItem item = t.addItem("hello");
@@ -342,7 +370,7 @@
 
   public void testTree() {
     // Simple widget
-    Tree t = new Tree();
+    Tree t = createTree();
     Label l = new Label("simple widget");
     TreeItem simple = new TreeItem(l);
     t.addItem(simple);
@@ -385,7 +413,7 @@
     assertEquals(t, eLabel.getParent());
 
     // Tree inside of Tree.
-    Tree childTree = new Tree();
+    Tree childTree = createTree();
     t.addItem(new TreeItem(childTree));
 
     // Swap TreeItems to new Tree.
@@ -399,4 +427,8 @@
     assertNull(eLabel.getParent());
     assertFalse(childTree.getChildWidgets().containsKey(eLabel.getParent()));
   }
+
+  private Tree createTree() {
+    return new Tree();
+  }
 }