Make EdgeDims and BoxConstraints printable (for debugging)

sky/sdk/lib/framework/rendering/box.dart

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 import 'dart:math' as math;
 import 'dart:sky' as sky;
 import 'dart:typed_data';
 import 'node.dart';
 import 'package:vector_math/vector_math.dart';
 import 'package:sky/framework/net/image_cache.dart' as image_cache;
@@ skipping 18 matching lines @@
 
   final double top;
   final double right;
   final double bottom;
   final double left;
 
   operator ==(EdgeDims other) => (top == other.top) ||
                                  (right == other.right) ||
                                  (bottom == other.bottom) ||
                                  (left == other.left);
+
+  int get hashCode {
+    value = 373;
+    value = 37 * value + top.hashCode;

[eseidel, 2015/06/03 23:23:16]

Why the magic number?  And doesn't dart have a *=?

+    value = 37 * value + left.hashCode;
+    value = 37 * value + bottom.hashCode;
+    value = 37 * value + right.hashCode;
+    return value;
+  }
+  String toString() => "EdgeDims($top, $right, $bottom, $left)";
 }
 
 class BoxConstraints {
   const BoxConstraints({
     this.minWidth: 0.0,
     this.maxWidth: double.INFINITY,
     this.minHeight: 0.0,
     this.maxHeight: double.INFINITY});
 
   BoxConstraints.tight(sky.Size size)
@@ skipping 31 matching lines @@
 
   double constrainHeight(double height) {
     return clamp(min: minHeight, max: maxHeight, value: height);
   }
 
   sky.Size constrain(sky.Size size) {
     return new sky.Size(constrainWidth(size.width), constrainHeight(size.height));
   }
 
   bool get isInfinite => maxWidth >= double.INFINITY || maxHeight >= double.INFINITY;
+
+  int get hashCode {
+    value = 373;
+    value = 37 * value + minWidth.hashCode;

[eseidel, 2015/06/03 23:23:16]

Maybe we want a hash() helper which can take N num values and spit out a hash?

+    value = 37 * value + maxWidth.hashCode;
+    value = 37 * value + minHeight.hashCode;
+    value = 37 * value + maxHeight.hashCode;
+    return value;
+  }
+  String toString() => "BoxConstraints($minWidth<=w<$maxWidth, $minHeight<=h<$maxHeight)";
 }
 
 class BoxParentData extends ParentData {
   sky.Point position = new sky.Point(0.0, 0.0);
 }
 
 abstract class RenderBox extends RenderNode {
 
   void setParentData(RenderNode child) {
     if (child.parentData is! BoxParentData)
@@ skipping 438 matching lines @@
 
   void defaultPaint(RenderNodeDisplayList canvas) {
     RenderBox child = firstChild;
     while (child != null) {
       assert(child.parentData is ParentDataType);
       canvas.paintChild(child, child.parentData.position);
       child = child.parentData.nextSibling;
     }
   }
 }