diff --git a/packages/flutter/lib/src/rendering/flex.dart b/packages/flutter/lib/src/rendering/flex.dart
index a7e7341d64a..d46a9c6d588 100644
--- a/packages/flutter/lib/src/rendering/flex.dart
+++ b/packages/flutter/lib/src/rendering/flex.dart
@@ -358,11 +358,11 @@ class RenderFlex extends RenderBox with ContainerRenderObjectMixin<RenderBox, Fl
         if (alignItems == FlexAlignItems.stretch) {
           switch (_direction) {
             case FlexDirection.horizontal:
-              innerConstraints = new BoxConstraints(minHeight: constraints.minHeight,
+              innerConstraints = new BoxConstraints(minHeight: constraints.maxHeight,
                                                     maxHeight: constraints.maxHeight);
               break;
             case FlexDirection.vertical:
-              innerConstraints = new BoxConstraints(minWidth: constraints.minWidth,
+              innerConstraints = new BoxConstraints(minWidth: constraints.maxWidth,
                                                     maxWidth: constraints.maxWidth);
               break;
           }
diff --git a/packages/unit/test/rendering/flex_test.dart b/packages/unit/test/rendering/flex_test.dart
index 0881d972523..a27ef65b53f 100644
--- a/packages/unit/test/rendering/flex_test.dart
+++ b/packages/unit/test/rendering/flex_test.dart
@@ -8,9 +8,67 @@ void main() {
     RenderDecoratedBox box = new RenderDecoratedBox(decoration: new BoxDecoration());
     RenderFlex flex = new RenderFlex(children: [ box ]);
     layout(flex, constraints: const BoxConstraints(
-      minWidth: 200.0, maxWidth: 100.0, minHeight: 200.0, maxHeight: 100.0));
+      minWidth: 200.0, maxWidth: 100.0, minHeight: 200.0, maxHeight: 100.0)
+    );
 
     expect(flex.size.width, equals(200.0), reason: "flex width");
     expect(flex.size.height, equals(200.0), reason: "flex height");
   });
+
+  test('Defaults', () {
+    RenderFlex flex = new RenderFlex();
+    expect(flex.alignItems, equals(FlexAlignItems.center));
+    expect(flex.direction, equals(FlexDirection.horizontal));
+  });
+
+  test('Parent data', () {
+    RenderDecoratedBox box1 = new RenderDecoratedBox(decoration: new BoxDecoration());
+    RenderDecoratedBox box2 = new RenderDecoratedBox(decoration: new BoxDecoration());
+    RenderFlex flex = new RenderFlex(children: [ box1, box2 ]);
+    layout(flex, constraints: const BoxConstraints(
+      minWidth: 0.0, maxWidth: 100.0, minHeight: 0.0, maxHeight: 100.0)
+    );
+    expect(box1.size.width, equals(0.0));
+    expect(box1.size.height, equals(0.0));
+    expect(box2.size.width, equals(0.0));
+    expect(box2.size.height, equals(0.0));
+
+    box2.parentData.flex = 1;
+    flex.markNeedsLayout();
+    pumpFrame();
+    expect(box1.size.width, equals(0.0));
+    expect(box1.size.height, equals(0.0));
+    expect(box2.size.width, equals(100.0));
+    expect(box2.size.height, equals(0.0));
+  });
+
+  test('Stretch', () {
+    RenderDecoratedBox box1 = new RenderDecoratedBox(decoration: new BoxDecoration());
+    RenderDecoratedBox box2 = new RenderDecoratedBox(decoration: new BoxDecoration());
+    RenderFlex flex = new RenderFlex();
+    flex.setupParentData(box2);
+    box2.parentData.flex = 2;
+    flex.addAll([box1, box2]);
+    layout(flex, constraints: const BoxConstraints(
+      minWidth: 0.0, maxWidth: 100.0, minHeight: 0.0, maxHeight: 100.0)
+    );
+    expect(box1.size.width, equals(0.0));
+    expect(box1.size.height, equals(0.0));
+    expect(box2.size.width, equals(100.0));
+    expect(box2.size.height, equals(0.0));
+
+    flex.alignItems = FlexAlignItems.stretch;
+    pumpFrame();
+    expect(box1.size.width, equals(0.0));
+    expect(box1.size.height, equals(100.0));
+    expect(box2.size.width, equals(100.0));
+    expect(box2.size.height, equals(100.0));
+
+    flex.direction = FlexDirection.vertical;
+    pumpFrame();
+    expect(box1.size.width, equals(100.0));
+    expect(box1.size.height, equals(0.0));
+    expect(box2.size.width, equals(100.0));
+    expect(box2.size.height, equals(100.0));
+  });
 }