Add support for measure mode

TestResult.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8" standalone="no"?>
+<!--This file represents the results of running a test suite-->
+<test-results name="src/csharp/Facebook.CSSLayout.Tests/bin/Release/Facebook.CSSLayout.Tests.dll" total="0" failures="0" not-run="0" date="2016-04-01" time="11:01:04">
+  <environment nunit-version="2.4.8.0" clr-version="4.0.30319.17020" os-version="Unix 15.4.0.0" platform="Unix" cwd="/Users/emilsj/css-layout" machine-name="emilsj-pro" user="emilsj" user-domain="emilsj-pro" />
+  <culture-info current-culture="en-US" current-uiculture="en-US" />
+  <test-suite name="src/csharp/Facebook.CSSLayout.Tests/bin/Release/Facebook.CSSLayout.Tests.dll" success="True" time="0.001" asserts="0">
+    <results />
+  </test-suite>
+</test-results>

dist/css-layout.h

@@ -80,6 +80,12 @@ typedef enum {
   CSS_POSITION_COUNT
 } css_position_t;
 
+typedef enum {
+  CSS_MEASURE_MODE_UNDEFINED = 0,
+  CSS_MEASURE_MODE_EXACTLY,
+  CSS_MEASURE_MODE_AT_MOST
+} css_measure_mode_t;
+
 typedef enum {
   CSS_WIDTH = 0,
   CSS_HEIGHT
@@ -144,7 +150,7 @@ struct css_node {
   css_node_t *next_absolute_child;
   css_node_t *next_flex_child;
 
-  css_dim_t (*measure)(void *context, float width, float height);
+  css_dim_t (*measure)(void *context, float width, css_measure_mode_t widthMode, float height, css_measure_mode_t heightMode);
   void (*print)(void *context);
   struct css_node* (*get_child)(void *context, int i);
   bool (*is_dirty)(void *context);
@@ -734,26 +740,40 @@ static void layoutNodeImpl(css_node_t *node, float parentMaxWidth, float parentM
     bool isResolvedRowDimDefined = isLayoutDimDefined(node, resolvedRowAxis);
 
     float width = CSS_UNDEFINED;
+    css_measure_mode_t widthMode = CSS_MEASURE_MODE_UNDEFINED;
     if (isStyleDimDefined(node, resolvedRowAxis)) {
       width = node->style.dimensions[CSS_WIDTH];
+      widthMode = CSS_MEASURE_MODE_EXACTLY;
     } else if (isResolvedRowDimDefined) {
       width = node->layout.dimensions[dim[resolvedRowAxis]];
+      widthMode = CSS_MEASURE_MODE_EXACTLY;
     } else {
       width = parentMaxWidth -
         getMarginAxis(node, resolvedRowAxis);
+      widthMode = CSS_MEASURE_MODE_AT_MOST;
     }
     width -= paddingAndBorderAxisResolvedRow;
+    if (isUndefined(width)) {
+      widthMode = CSS_MEASURE_MODE_UNDEFINED;
+    }
 
     float height = CSS_UNDEFINED;
+    css_measure_mode_t heightMode = CSS_MEASURE_MODE_UNDEFINED;
     if (isStyleDimDefined(node, CSS_FLEX_DIRECTION_COLUMN)) {
       height = node->style.dimensions[CSS_HEIGHT];
+      heightMode = CSS_MEASURE_MODE_EXACTLY;
     } else if (isLayoutDimDefined(node, CSS_FLEX_DIRECTION_COLUMN)) {
       height = node->layout.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]];
+      heightMode = CSS_MEASURE_MODE_EXACTLY;
     } else {
       height = parentMaxHeight -
         getMarginAxis(node, resolvedRowAxis);
+      heightMode = CSS_MEASURE_MODE_AT_MOST;
     }
     height -= getPaddingAndBorderAxis(node, CSS_FLEX_DIRECTION_COLUMN);
+    if (isUndefined(height)) {
+      heightMode = CSS_MEASURE_MODE_UNDEFINED;
+    }
 
     // We only need to give a dimension for the text if we haven't got any
     // for it computed yet. It can either be from the style attribute or because
@@ -768,7 +788,9 @@ static void layoutNodeImpl(css_node_t *node, float parentMaxWidth, float parentM
         node->context,
         
         width,
-        height
+        widthMode,
+        height,
+        heightMode
       );
       if (isRowUndefined) {
         node->layout.dimensions[CSS_WIDTH] = measureDim.dimensions[CSS_WIDTH] +
@@ -1447,8 +1469,8 @@ void layoutNode(css_node_t *node, float parentMaxWidth, float parentMaxHeight, c
     !node->is_dirty(node->context) &&
     eq(layout->last_requested_dimensions[CSS_WIDTH], layout->dimensions[CSS_WIDTH]) &&
     eq(layout->last_requested_dimensions[CSS_HEIGHT], layout->dimensions[CSS_HEIGHT]) &&
-    eq(layout->last_parent_max_width, parentMaxWidth);
+    eq(layout->last_parent_max_width, parentMaxWidth) &&
-    eq(layout->last_parent_max_height, parentMaxHeight);
+    eq(layout->last_parent_max_height, parentMaxHeight) &&
     eq(layout->last_direction, direction);
 
   if (skipLayout) {

dist/css-layout.js

@@ -53,6 +53,10 @@ var computeLayout = (function() {
   var CSS_POSITION_RELATIVE = 'relative';
   var CSS_POSITION_ABSOLUTE = 'absolute';
 
+  var CSS_MEASURE_MODE_UNDEFINED = 'undefined';
+  var CSS_MEASURE_MODE_EXACTLY = 'exactly';
+  var CSS_MEASURE_MODE_AT_MOST = 'at-most';
+
   var leading = {
     'row': 'left',
     'row-reverse': 'right',
@@ -110,7 +114,7 @@ var computeLayout = (function() {
   }
 
   function isUndefined(value) {
-    return value === undefined;
+    return value === undefined || isNaN(value);
   }
 
   function isRowDirection(flexDirection) {
@@ -501,26 +505,40 @@ var computeLayout = (function() {
       var/*bool*/ isResolvedRowDimDefined = isLayoutDimDefined(node, resolvedRowAxis);
 
       var/*float*/ width = CSS_UNDEFINED;
+      var/*css_measure_mode_t*/ widthMode = CSS_MEASURE_MODE_UNDEFINED;
       if (isStyleDimDefined(node, resolvedRowAxis)) {
         width = node.style.width;
+        widthMode = CSS_MEASURE_MODE_EXACTLY;
       } else if (isResolvedRowDimDefined) {
         width = node.layout[dim[resolvedRowAxis]];
+        widthMode = CSS_MEASURE_MODE_EXACTLY;
       } else {
         width = parentMaxWidth -
           getMarginAxis(node, resolvedRowAxis);
+        widthMode = CSS_MEASURE_MODE_AT_MOST;
       }
       width -= paddingAndBorderAxisResolvedRow;
+      if (isUndefined(width)) {
+        widthMode = CSS_MEASURE_MODE_UNDEFINED;
+      }
 
       var/*float*/ height = CSS_UNDEFINED;
+      var/*css_measure_mode_t*/ heightMode = CSS_MEASURE_MODE_UNDEFINED;
       if (isStyleDimDefined(node, CSS_FLEX_DIRECTION_COLUMN)) {
         height = node.style.height;
+        heightMode = CSS_MEASURE_MODE_EXACTLY;
       } else if (isLayoutDimDefined(node, CSS_FLEX_DIRECTION_COLUMN)) {
         height = node.layout[dim[CSS_FLEX_DIRECTION_COLUMN]];
+        heightMode = CSS_MEASURE_MODE_EXACTLY;
       } else {
         height = parentMaxHeight -
           getMarginAxis(node, resolvedRowAxis);
+        heightMode = CSS_MEASURE_MODE_AT_MOST;
       }
       height -= getPaddingAndBorderAxis(node, CSS_FLEX_DIRECTION_COLUMN);
+      if (isUndefined(height)) {
+        heightMode = CSS_MEASURE_MODE_UNDEFINED;
+      }
 
       // We only need to give a dimension for the text if we haven't got any
       // for it computed yet. It can either be from the style attribute or because
@@ -535,7 +553,9 @@ var computeLayout = (function() {
           /*(c)!node->context,*/
           /*(java)!layoutContext.measureOutput,*/
           width,
-          height
+          widthMode,
+          height,
+          heightMode
         );
         if (isRowUndefined) {
           node.layout.width = measureDim.width +

src/CSharpTranspiler.js

@@ -11,12 +11,14 @@ function __transpileToCSharpCommon(code) {
   return code
     .replace(/CSS_UNDEFINED/g, 'CSSConstants.UNDEFINED')
     .replace(/CSS_JUSTIFY_/g, 'CSSJustify.')
+    .replace(/CSS_MEASURE_MODE_/g, 'CSSMeasureMode.')
     .replace(/CSS_ALIGN_/g, 'CSSAlign.')
     .replace(/CSS_POSITION_/g, 'CSSPositionType.')
     .replace(/css_flex_direction_t/g, 'CSSFlexDirection')
     .replace(/css_direction_t/g, 'CSSDirection')
     .replace(/css_align_t/g, 'CSSAlign')
     .replace(/css_justify_t/g, 'CSSJustify')
+    .replace(/css_measure_mode_t/g, 'CSSMeasureMode')
     .replace(/css_dim_t/g, 'MeasureOutput')
     .replace(/bool/g, 'boolean')
     .replace(/style\[dim/g, 'style.dimensions[dim')
@@ -56,7 +58,7 @@ function __transpileToCSharpCommon(code) {
 
     // additional case conversions
 
-    .replace(/(CSSConstants|CSSWrap|CSSJustify|CSSAlign|CSSPositionType)\.([_A-Z]+)/g,
+    .replace(/(CSSConstants|CSSWrap|CSSJustify|CSSMeasureMode|CSSAlign|CSSPositionType)\.([_A-Z]+)/g,
         function(str, match1, match2) {
           return match1 + '.' + constantToPascalCase(match2);
         });

src/JavaTranspiler.js

@@ -11,12 +11,14 @@ function __transpileToJavaCommon(code) {
   return code
     .replace(/CSS_UNDEFINED/g, 'CSSConstants.UNDEFINED')
     .replace(/CSS_JUSTIFY_/g, 'CSSJustify.')
+    .replace(/CSS_MEASURE_MODE_/g, 'CSSMeasureMode.')
     .replace(/CSS_ALIGN_/g, 'CSSAlign.')
     .replace(/CSS_POSITION_/g, 'CSSPositionType.')
     .replace(/css_flex_direction_t/g, 'CSSFlexDirection')
     .replace(/css_direction_t/g, 'CSSDirection')
     .replace(/css_align_t/g, 'CSSAlign')
     .replace(/css_justify_t/g, 'CSSJustify')
+    .replace(/css_measure_mode_t/g, 'CSSMeasureMode')
     .replace(/css_dim_t/g, 'MeasureOutput')
     .replace(/bool/g, 'boolean')
     .replace(/style\[dim/g, 'style.dimensions[dim')

src/Layout-test-utils.c

@@ -82,11 +82,11 @@ static bool are_layout_equal(css_node_t *a, css_node_t *b) {
   return true;
 }
 
-css_dim_t measure(void *context, float width, float height) {
+css_dim_t measure(void *context, float width, css_measure_mode_t widthMode, float height, css_measure_mode_t heightMode) {
   const char *text = (const char *)context;
   css_dim_t dim;
   if (strcmp(text, SMALL_TEXT) == 0) {
-    if (width != width) {
+    if (widthMode == CSS_MEASURE_MODE_UNDEFINED) {
       width = 1000000;
     }
     dim.dimensions[CSS_WIDTH] = fminf(SMALL_WIDTH, width);
@@ -94,7 +94,7 @@ css_dim_t measure(void *context, float width, float height) {
     return dim;
   }
   if (strcmp(text, LONG_TEXT) == 0) {
-    if (width != width) {
+    if (widthMode == CSS_MEASURE_MODE_UNDEFINED) {
       width = 1000000;
     }
     dim.dimensions[CSS_WIDTH] = width >= BIG_WIDTH ? BIG_WIDTH : fmaxf(BIG_MIN_WIDTH, width);
@@ -103,10 +103,10 @@ css_dim_t measure(void *context, float width, float height) {
   }
 
   if (strcmp(text, MEASURE_WITH_RATIO_2) == 0) {
-    if (width > 0) {
+    if (widthMode != CSS_MEASURE_MODE_UNDEFINED) {
       dim.dimensions[CSS_WIDTH] = width;
       dim.dimensions[CSS_HEIGHT] = width * 2;
-    } else if (height > 0) {
+    } else if (heightMode != CSS_MEASURE_MODE_UNDEFINED) {
       dim.dimensions[CSS_WIDTH] = height * 2;
       dim.dimensions[CSS_HEIGHT] = height;
     } else {
@@ -117,6 +117,12 @@ css_dim_t measure(void *context, float width, float height) {
   }
 
   if (strcmp(text, MEASURE_WITH_MATCH_PARENT) == 0) {
+    if (widthMode == CSS_MEASURE_MODE_UNDEFINED) {
+      width = 99999;
+    }
+    if (heightMode == CSS_MEASURE_MODE_UNDEFINED) {
+      height = 99999;
+    }
     dim.dimensions[CSS_WIDTH] = width;
     dim.dimensions[CSS_HEIGHT] = height;
     return dim;

src/Layout-test-utils.h

@@ -13,6 +13,6 @@
 
 void test(const char *name, css_node_t *style, css_node_t *expected_layout);
 int tests_finished(void);
-css_dim_t measure(void *context, float width, float height);
+css_dim_t measure(void *context, float width, css_measure_mode_t widthMode, float height, css_measure_mode_t heightMode);
 void init_css_node_children(css_node_t *node, int children_count);
 css_node_t *new_test_css_node(void);

src/Layout-test-utils.js

@@ -494,8 +494,8 @@ var layoutTestUtils = (function() {
     computeDOMLayout: computeDOMLayout,
     reduceTest: reduceTest,
     text: function(text) {
-      var fn = function(width, height) {
+      var fn = function(width, widthMode, height, heightMode) {
-        if (width === undefined || isNaN(width)) {
+        if (widthMode === 'undefined') {
           width = Infinity;
         }
 
@@ -522,10 +522,10 @@ var layoutTestUtils = (function() {
       return fn;
     },
     measureWithRatio2: function() {
-      var fn = function(width, height) {
+      var fn = function(width, widthMode, height, heightMode) {
-        if (width > 0) {
+        if (widthMode !== 'undefined') {
           height = width * 2;
-        } else if (height > 0) {
+        } else if (heightMode !== 'undefined') {
           width = height * 2;
         } else {
           // This should be Infinity, but it would be pain to transpile,
@@ -540,7 +540,13 @@ var layoutTestUtils = (function() {
       return fn;
     },
     measureWithMatchParent: function() {
-      var fn = function(width, height) {
+      var fn = function(width, widthMode, height, heightMode) {
+        if (widthMode === 'undefined') {
+          width = 99999;
+        }
+        if (heightMode === 'undefined') {
+          height = 99999;
+        }
         return {width: width, height: height};
       };
       // This is necessary for transpiled tests, see previous comment

src/Layout.c

@@ -557,26 +557,40 @@ static void layoutNodeImpl(css_node_t *node, float parentMaxWidth, float parentM
     bool isResolvedRowDimDefined = isLayoutDimDefined(node, resolvedRowAxis);
 
     float width = CSS_UNDEFINED;
+    css_measure_mode_t widthMode = CSS_MEASURE_MODE_UNDEFINED;
     if (isStyleDimDefined(node, resolvedRowAxis)) {
       width = node->style.dimensions[CSS_WIDTH];
+      widthMode = CSS_MEASURE_MODE_EXACTLY;
     } else if (isResolvedRowDimDefined) {
       width = node->layout.dimensions[dim[resolvedRowAxis]];
+      widthMode = CSS_MEASURE_MODE_EXACTLY;
     } else {
       width = parentMaxWidth -
         getMarginAxis(node, resolvedRowAxis);
+      widthMode = CSS_MEASURE_MODE_AT_MOST;
     }
     width -= paddingAndBorderAxisResolvedRow;
+    if (isUndefined(width)) {
+      widthMode = CSS_MEASURE_MODE_UNDEFINED;
+    }
 
     float height = CSS_UNDEFINED;
+    css_measure_mode_t heightMode = CSS_MEASURE_MODE_UNDEFINED;
     if (isStyleDimDefined(node, CSS_FLEX_DIRECTION_COLUMN)) {
       height = node->style.dimensions[CSS_HEIGHT];
+      heightMode = CSS_MEASURE_MODE_EXACTLY;
     } else if (isLayoutDimDefined(node, CSS_FLEX_DIRECTION_COLUMN)) {
       height = node->layout.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]];
+      heightMode = CSS_MEASURE_MODE_EXACTLY;
     } else {
       height = parentMaxHeight -
         getMarginAxis(node, resolvedRowAxis);
+      heightMode = CSS_MEASURE_MODE_AT_MOST;
     }
     height -= getPaddingAndBorderAxis(node, CSS_FLEX_DIRECTION_COLUMN);
+    if (isUndefined(height)) {
+      heightMode = CSS_MEASURE_MODE_UNDEFINED;
+    }
 
     // We only need to give a dimension for the text if we haven't got any
     // for it computed yet. It can either be from the style attribute or because
@@ -591,7 +605,9 @@ static void layoutNodeImpl(css_node_t *node, float parentMaxWidth, float parentM
         node->context,
         
         width,
-        height
+        widthMode,
+        height,
+        heightMode
       );
       if (isRowUndefined) {
         node->layout.dimensions[CSS_WIDTH] = measureDim.dimensions[CSS_WIDTH] +

src/Layout.h

@@ -76,6 +76,12 @@ typedef enum {
   CSS_POSITION_COUNT
 } css_position_t;
 
+typedef enum {
+  CSS_MEASURE_MODE_UNDEFINED = 0,
+  CSS_MEASURE_MODE_EXACTLY,
+  CSS_MEASURE_MODE_AT_MOST
+} css_measure_mode_t;
+
 typedef enum {
   CSS_WIDTH = 0,
   CSS_HEIGHT
@@ -140,7 +146,7 @@ struct css_node {
   css_node_t *next_absolute_child;
   css_node_t *next_flex_child;
 
-  css_dim_t (*measure)(void *context, float width, float height);
+  css_dim_t (*measure)(void *context, float width, css_measure_mode_t widthMode, float height, css_measure_mode_t heightMode);
   void (*print)(void *context);
   struct css_node* (*get_child)(void *context, int i);
   bool (*is_dirty)(void *context);

src/Layout.js

@@ -34,6 +34,10 @@ var computeLayout = (function() {
   var CSS_POSITION_RELATIVE = 'relative';
   var CSS_POSITION_ABSOLUTE = 'absolute';
 
+  var CSS_MEASURE_MODE_UNDEFINED = 'undefined';
+  var CSS_MEASURE_MODE_EXACTLY = 'exactly';
+  var CSS_MEASURE_MODE_AT_MOST = 'at-most';
+
   var leading = {
     'row': 'left',
     'row-reverse': 'right',
@@ -91,7 +95,7 @@ var computeLayout = (function() {
   }
 
   function isUndefined(value) {
-    return value === undefined;
+    return value === undefined || isNaN(value);
   }
 
   function isRowDirection(flexDirection) {
@@ -482,26 +486,40 @@ var computeLayout = (function() {
       var/*bool*/ isResolvedRowDimDefined = isLayoutDimDefined(node, resolvedRowAxis);
 
       var/*float*/ width = CSS_UNDEFINED;
+      var/*css_measure_mode_t*/ widthMode = CSS_MEASURE_MODE_UNDEFINED;
       if (isStyleDimDefined(node, resolvedRowAxis)) {
         width = node.style.width;
+        widthMode = CSS_MEASURE_MODE_EXACTLY;
       } else if (isResolvedRowDimDefined) {
         width = node.layout[dim[resolvedRowAxis]];
+        widthMode = CSS_MEASURE_MODE_EXACTLY;
       } else {
         width = parentMaxWidth -
           getMarginAxis(node, resolvedRowAxis);
+        widthMode = CSS_MEASURE_MODE_AT_MOST;
       }
       width -= paddingAndBorderAxisResolvedRow;
+      if (isUndefined(width)) {
+        widthMode = CSS_MEASURE_MODE_UNDEFINED;
+      }
 
       var/*float*/ height = CSS_UNDEFINED;
+      var/*css_measure_mode_t*/ heightMode = CSS_MEASURE_MODE_UNDEFINED;
       if (isStyleDimDefined(node, CSS_FLEX_DIRECTION_COLUMN)) {
         height = node.style.height;
+        heightMode = CSS_MEASURE_MODE_EXACTLY;
       } else if (isLayoutDimDefined(node, CSS_FLEX_DIRECTION_COLUMN)) {
         height = node.layout[dim[CSS_FLEX_DIRECTION_COLUMN]];
+        heightMode = CSS_MEASURE_MODE_EXACTLY;
       } else {
         height = parentMaxHeight -
           getMarginAxis(node, resolvedRowAxis);
+        heightMode = CSS_MEASURE_MODE_AT_MOST;
       }
       height -= getPaddingAndBorderAxis(node, CSS_FLEX_DIRECTION_COLUMN);
+      if (isUndefined(height)) {
+        heightMode = CSS_MEASURE_MODE_UNDEFINED;
+      }
 
       // We only need to give a dimension for the text if we haven't got any
       // for it computed yet. It can either be from the style attribute or because
@@ -516,7 +534,9 @@ var computeLayout = (function() {
           /*(c)!node->context,*/
           /*(java)!layoutContext.measureOutput,*/
           width,
-          height
+          widthMode,
+          height,
+          heightMode
         );
         if (isRowUndefined) {
           node.layout.width = measureDim.width +

src/csharp/Facebook.CSSLayout.Tests/LayoutCachingTest.cs

@@ -226,7 +226,7 @@ namespace Facebook.CSSLayout.Tests
             root.calculateLayout();
             markLayoutAppliedForTree(root);
 
-            c1.setMeasureFunction((node, width, height) => new MeasureOutput(100, 20));
+            c1.setMeasureFunction((node, width, widthMode, height, heightMode) => new MeasureOutput(100, 20));
 
             root.calculateLayout();
 

src/csharp/Facebook.CSSLayout.Tests/LayoutEngineTest.cs

@@ -25,11 +25,11 @@ public class LayoutEngineTest
     const int DIMENSION_HEIGHT = CSSLayout.DIMENSION_HEIGHT;
     const int DIMENSION_WIDTH = CSSLayout.DIMENSION_WIDTH;
 
-    static readonly MeasureFunction sTestMeasureFunction = (node, width, height) =>
+    static readonly MeasureFunction sTestMeasureFunction = (node, width, widthMode, height, heightMode) =>
     {
         TestCSSNode testNode = (TestCSSNode) node;
         if (testNode.context.Equals(TestConstants.SMALL_TEXT)) {
-            if (CSSConstants.IsUndefined(width)) {
+            if (widthMode == CSSMeasureMode.Undefined) {
                 width = 10000000;
             }
             return new MeasureOutput(
@@ -46,14 +46,20 @@ public class LayoutEngineTest
                     ? TestConstants.SMALL_HEIGHT
                     : TestConstants.BIG_HEIGHT);
         } else if (testNode.context.Equals(TestConstants.MEASURE_WITH_RATIO_2)) {
-            if (width > 0) {
+            if (widthMode != CSSMeasureMode.Undefined) {
                 return new MeasureOutput(width, width * 2);
-            } else if (height > 0) {
+            } else if (heightMode != CSSMeasureMode.Undefined) {
                 return new MeasureOutput(height * 2, height);
             } else {
               return new MeasureOutput(99999, 99999);
             }
         } else if (testNode.context.Equals(TestConstants.MEASURE_WITH_MATCH_PARENT)) {
+            if (widthMode == CSSMeasureMode.Undefined) {
+              width = 99999;
+            }
+            if (heightMode == CSSMeasureMode.Undefined) {
+              height = 99999;
+            }
             return new MeasureOutput(width, height);
         } else {
             throw new Exception("Got unknown test: " + testNode.context);

src/csharp/Facebook.CSSLayout/CSSMeasureMode.cs

@@ -0,0 +1,18 @@
+/**
+ * Copyright (c) 2014, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+namespace Facebook.CSSLayout
+{
+    public enum CSSMeasureMode
+    {
+        Undefined,
+        Exactly,
+        AtMost,
+    }
+}

src/csharp/Facebook.CSSLayout/CSSNode.cs

@@ -17,7 +17,7 @@ namespace Facebook.CSSLayout
      * Should measure the given node and put the result in the given MeasureOutput.
      */
 
-    public delegate MeasureOutput MeasureFunction(CSSNode node, float width, float height);
+    public delegate MeasureOutput MeasureFunction(CSSNode node, float width, CSSMeasureMode widthMode, float height, CSSMeasureMode heightMode);
 
     /**
      * A CSS Node. It has a style object you can manipulate at {@link #style}. After calling
@@ -140,13 +140,13 @@ namespace Facebook.CSSLayout
             get { return mMeasureFunction != null; }
         }
 
-        internal MeasureOutput measure(MeasureOutput measureOutput, float width, float height)
+        internal MeasureOutput measure(MeasureOutput measureOutput, float width, CSSMeasureMode widthMode, float height, CSSMeasureMode heightMode)
         {
             if (!IsMeasureDefined)
             {
                 throw new Exception("Measure function isn't defined!");
             }
-            return Assertions.assertNotNull(mMeasureFunction)(this, width, height);
+            return Assertions.assertNotNull(mMeasureFunction)(this, width, widthMode, height, heightMode);
         }
 
         /**

src/csharp/Facebook.CSSLayout/Facebook.CSSLayout.csproj

@@ -45,6 +45,7 @@
     <Compile Include="CSSDirection.cs" />
     <Compile Include="CSSFlexDirection.cs" />
     <Compile Include="CSSJustify.cs" />
+    <Compile Include="CSSMeasureMode.cs" />
     <Compile Include="CSSLayout.cs" />
     <Compile Include="CSSLayoutContext.cs" />
     <Compile Include="CSSNode.cs" />
@@ -67,4 +68,4 @@
   <Target Name="AfterBuild">
   </Target>
   -->
-</Project>
+</Project>

src/csharp/Facebook.CSSLayout/LayoutEngine.cs

@@ -282,26 +282,40 @@ namespace Facebook.CSSLayout
         boolean isResolvedRowDimDefined = (!float.IsNaN(node.layout.dimensions[dim[resolvedRowAxis]]) && node.layout.dimensions[dim[resolvedRowAxis]] >= 0.0);
     
         float width = CSSConstants.Undefined;
+        CSSMeasureMode widthMode = CSSMeasureMode.Undefined;
         if ((!float.IsNaN(node.style.dimensions[dim[resolvedRowAxis]]) && node.style.dimensions[dim[resolvedRowAxis]] >= 0.0)) {
           width = node.style.dimensions[DIMENSION_WIDTH];
+          widthMode = CSSMeasureMode.Exactly;
         } else if (isResolvedRowDimDefined) {
           width = node.layout.dimensions[dim[resolvedRowAxis]];
+          widthMode = CSSMeasureMode.Exactly;
         } else {
           width = parentMaxWidth -
             (node.style.margin.getWithFallback(leadingSpacing[resolvedRowAxis], leading[resolvedRowAxis]) + node.style.margin.getWithFallback(trailingSpacing[resolvedRowAxis], trailing[resolvedRowAxis]));
+          widthMode = CSSMeasureMode.AtMost;
         }
         width -= paddingAndBorderAxisResolvedRow;
+        if (float.IsNaN(width)) {
+          widthMode = CSSMeasureMode.Undefined;
+        }
     
         float height = CSSConstants.Undefined;
+        CSSMeasureMode heightMode = CSSMeasureMode.Undefined;
         if ((!float.IsNaN(node.style.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]]) && node.style.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]] >= 0.0)) {
           height = node.style.dimensions[DIMENSION_HEIGHT];
+          heightMode = CSSMeasureMode.Exactly;
         } else if ((!float.IsNaN(node.layout.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]]) && node.layout.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]] >= 0.0)) {
           height = node.layout.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]];
+          heightMode = CSSMeasureMode.Exactly;
         } else {
           height = parentMaxHeight -
             (node.style.margin.getWithFallback(leadingSpacing[resolvedRowAxis], leading[resolvedRowAxis]) + node.style.margin.getWithFallback(trailingSpacing[resolvedRowAxis], trailing[resolvedRowAxis]));
+          heightMode = CSSMeasureMode.AtMost;
         }
         height -= ((node.style.padding.getWithFallback(leadingSpacing[CSS_FLEX_DIRECTION_COLUMN], leading[CSS_FLEX_DIRECTION_COLUMN]) + node.style.border.getWithFallback(leadingSpacing[CSS_FLEX_DIRECTION_COLUMN], leading[CSS_FLEX_DIRECTION_COLUMN])) + (node.style.padding.getWithFallback(trailingSpacing[CSS_FLEX_DIRECTION_COLUMN], trailing[CSS_FLEX_DIRECTION_COLUMN]) + node.style.border.getWithFallback(trailingSpacing[CSS_FLEX_DIRECTION_COLUMN], trailing[CSS_FLEX_DIRECTION_COLUMN])));
+        if (float.IsNaN(height)) {
+          heightMode = CSSMeasureMode.Undefined;
+        }
     
         // We only need to give a dimension for the text if we haven't got any
         // for it computed yet. It can either be from the style attribute or because
@@ -316,7 +330,9 @@ namespace Facebook.CSSLayout
             
             layoutContext.measureOutput,
             width,
-            height
+            widthMode,
+            height,
+            heightMode
           );
           if (isRowUndefined) {
             node.layout.dimensions[DIMENSION_WIDTH] = measureDim.width +

src/java/src/com/facebook/csslayout/CSSMeasureMode.java

@@ -0,0 +1,15 @@
+/**
+ * Copyright (c) 2014, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+package com.facebook.csslayout;
+
+public enum CSSMeasureMode {
+  UNDEFINED,
+  EXACTLY,
+  AT_MOST,
+}

src/java/src/com/facebook/csslayout/CSSNode.java

@@ -53,7 +53,7 @@ public class CSSNode {
      *
      * NB: measure is NOT guaranteed to be threadsafe/re-entrant safe!
      */
-    public void measure(CSSNode node, float width, float height, MeasureOutput measureOutput);
+    public void measure(CSSNode node, float width, CSSMeasureMode widthMode, float height, CSSMeasureMode heightMode, MeasureOutput measureOutput);
   }
 
   // VisibleForTesting
@@ -125,13 +125,13 @@ public class CSSNode {
     return mMeasureFunction != null;
   }
 
-  /*package*/ MeasureOutput measure(MeasureOutput measureOutput, float width, float height) {
+  /*package*/ MeasureOutput measure(MeasureOutput measureOutput, float width, CSSMeasureMode widthMode, float height, CSSMeasureMode heightMode) {
     if (!isMeasureDefined()) {
       throw new RuntimeException("Measure function isn't defined!");
     }
     measureOutput.height = CSSConstants.UNDEFINED;
     measureOutput.width = CSSConstants.UNDEFINED;
-    Assertions.assertNotNull(mMeasureFunction).measure(this, width, height, measureOutput);
+    Assertions.assertNotNull(mMeasureFunction).measure(this, width, widthMode, height, heightMode, measureOutput);
     return measureOutput;
   }
 

src/java/src/com/facebook/csslayout/LayoutEngine.java

@@ -258,26 +258,40 @@ public class LayoutEngine {
       boolean isResolvedRowDimDefined = (!Float.isNaN(node.layout.dimensions[dim[resolvedRowAxis]]) && node.layout.dimensions[dim[resolvedRowAxis]] >= 0.0);
   
       float width = CSSConstants.UNDEFINED;
+      CSSMeasureMode widthMode = CSSMeasureMode.UNDEFINED;
       if ((!Float.isNaN(node.style.dimensions[dim[resolvedRowAxis]]) && node.style.dimensions[dim[resolvedRowAxis]] >= 0.0)) {
         width = node.style.dimensions[DIMENSION_WIDTH];
+        widthMode = CSSMeasureMode.EXACTLY;
       } else if (isResolvedRowDimDefined) {
         width = node.layout.dimensions[dim[resolvedRowAxis]];
+        widthMode = CSSMeasureMode.EXACTLY;
       } else {
         width = parentMaxWidth -
           (node.style.margin.getWithFallback(leadingSpacing[resolvedRowAxis], leading[resolvedRowAxis]) + node.style.margin.getWithFallback(trailingSpacing[resolvedRowAxis], trailing[resolvedRowAxis]));
+        widthMode = CSSMeasureMode.AT_MOST;
       }
       width -= paddingAndBorderAxisResolvedRow;
+      if (Float.isNaN(width)) {
+        widthMode = CSSMeasureMode.UNDEFINED;
+      }
   
       float height = CSSConstants.UNDEFINED;
+      CSSMeasureMode heightMode = CSSMeasureMode.UNDEFINED;
       if ((!Float.isNaN(node.style.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]]) && node.style.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]] >= 0.0)) {
         height = node.style.dimensions[DIMENSION_HEIGHT];
+        heightMode = CSSMeasureMode.EXACTLY;
       } else if ((!Float.isNaN(node.layout.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]]) && node.layout.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]] >= 0.0)) {
         height = node.layout.dimensions[dim[CSS_FLEX_DIRECTION_COLUMN]];
+        heightMode = CSSMeasureMode.EXACTLY;
       } else {
         height = parentMaxHeight -
           (node.style.margin.getWithFallback(leadingSpacing[resolvedRowAxis], leading[resolvedRowAxis]) + node.style.margin.getWithFallback(trailingSpacing[resolvedRowAxis], trailing[resolvedRowAxis]));
+        heightMode = CSSMeasureMode.AT_MOST;
       }
       height -= ((node.style.padding.getWithFallback(leadingSpacing[CSS_FLEX_DIRECTION_COLUMN], leading[CSS_FLEX_DIRECTION_COLUMN]) + node.style.border.getWithFallback(leadingSpacing[CSS_FLEX_DIRECTION_COLUMN], leading[CSS_FLEX_DIRECTION_COLUMN])) + (node.style.padding.getWithFallback(trailingSpacing[CSS_FLEX_DIRECTION_COLUMN], trailing[CSS_FLEX_DIRECTION_COLUMN]) + node.style.border.getWithFallback(trailingSpacing[CSS_FLEX_DIRECTION_COLUMN], trailing[CSS_FLEX_DIRECTION_COLUMN])));
+      if (Float.isNaN(height)) {
+        heightMode = CSSMeasureMode.UNDEFINED;
+      }
   
       // We only need to give a dimension for the text if we haven't got any
       // for it computed yet. It can either be from the style attribute or because
@@ -292,7 +306,9 @@ public class LayoutEngine {
           
           layoutContext.measureOutput,
           width,
-          height
+          widthMode,
+          height,
+          heightMode
         );
         if (isRowUndefined) {
           node.layout.dimensions[DIMENSION_WIDTH] = measureDim.width +

src/java/tests/com/facebook/csslayout/LayoutCachingTest.java

@@ -223,7 +223,7 @@ public class LayoutCachingTest {
 
     c1.setMeasureFunction(new CSSNode.MeasureFunction() {
       @Override
-      public void measure(CSSNode node, float width, float height, MeasureOutput measureOutput) {
+      public void measure(CSSNode node, float width, CSSMeasureMode widthMode, float height, CSSMeasureMode heightMode, MeasureOutput measureOutput) {
         measureOutput.width = 100;
         measureOutput.height = 20;
       }

src/java/tests/com/facebook/csslayout/LayoutEngineTest.java

@@ -27,16 +27,16 @@ public class LayoutEngineTest {
       new CSSNode.MeasureFunction() {
 
     @Override
-    public void measure(CSSNode node, float width, float height, MeasureOutput measureOutput) {
+    public void measure(CSSNode node, float width, CSSMeasureMode widthMode, float height, CSSMeasureMode heightMode, MeasureOutput measureOutput) {
       TestCSSNode testNode = (TestCSSNode) node;
       if (testNode.context.equals(TestConstants.SMALL_TEXT)) {
-        if (CSSConstants.isUndefined(width)) {
+        if (widthMode == CSSMeasureMode.UNDEFINED) {
           width = 10000000;
         }
         measureOutput.width = Math.min(width, TestConstants.SMALL_WIDTH);
         measureOutput.height = TestConstants.SMALL_HEIGHT;
       } else if (testNode.context.equals(TestConstants.LONG_TEXT)) {
-        if (CSSConstants.isUndefined(width)) {
+        if (widthMode == CSSMeasureMode.UNDEFINED) {
           width = 10000000;
         }
         measureOutput.width = width >= TestConstants.BIG_WIDTH ?
@@ -44,10 +44,10 @@ public class LayoutEngineTest {
         measureOutput.height = width >= TestConstants.BIG_WIDTH ?
             TestConstants.SMALL_HEIGHT : TestConstants.BIG_HEIGHT;
       } else if (testNode.context.equals(TestConstants.MEASURE_WITH_RATIO_2)) {
-        if (width > 0) {
+        if (widthMode != CSSMeasureMode.UNDEFINED) {
           measureOutput.width = width;
           measureOutput.height = width * 2;
-        } else if (height > 0) {
+        } else if (heightMode != CSSMeasureMode.UNDEFINED) {
           measureOutput.width = height * 2;
           measureOutput.height = height;
         } else {
@@ -55,6 +55,12 @@ public class LayoutEngineTest {
           measureOutput.height = 99999;
         }
       } else if (testNode.context.equals(TestConstants.MEASURE_WITH_MATCH_PARENT)) {
+        if (widthMode == CSSMeasureMode.UNDEFINED) {
+          width = 99999;
+        }
+        if (heightMode == CSSMeasureMode.UNDEFINED) {
+          height = 99999;
+        }
         measureOutput.width = width;
         measureOutput.height = height;
       } else {

src/transpile.js

@@ -170,6 +170,11 @@ function printLayout(test) {
       'nowrap': 'CSS_NOWRAP',
       'wrap': 'CSS_WRAP'
     });
+    addEnum(node, 'measureMode', 'measure_mode', {
+      'undefined': 'CSS_MEASURE_MODE_UNDEFINED',
+      'exactly': 'CSS_MEASURE_MODE_EXACTLY',
+      'at-most': 'CSS_MEASURE_MODE_AT_MOST'
+    });
     addFloat(node, 'flex', 'flex');
     addFloat(node, 'width', 'dimensions[CSS_WIDTH]');
     addFloat(node, 'height', 'dimensions[CSS_HEIGHT]');