Add constructor in YGLayout

Summary: Add default constructor in YGLayout and moved to separate file. This diff also addresses https://github.com/facebook/yoga/pull/700

Reviewed By: emilsjolander

Differential Revision: D7019653

fbshipit-source-id: 5a2655626db0915fcebe7d4517e2d0b2e2484460

yoga/YGLayout.cpp

@@ -0,0 +1,73 @@
+/**
+ * Copyright (c) 2014-present, 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.
+ */
+#include "YGLayout.h"
+
+const std::array<float, 2> kYGDefaultDimensionValues = {
+    {YGUndefined, YGUndefined}};
+
+YGLayout::YGLayout()
+    : position(),
+      dimensions(kYGDefaultDimensionValues),
+      margin(),
+      border(),
+      padding(),
+      direction(YGDirectionInherit),
+      computedFlexBasisGeneration(0),
+      computedFlexBasis(YGUndefined),
+      hadOverflow(false),
+      generationCount(0),
+      lastParentDirection((YGDirection)-1),
+      nextCachedMeasurementsIndex(0),
+      cachedMeasurements(),
+      measuredDimensions(kYGDefaultDimensionValues),
+      cachedLayout({
+          .availableWidth = 0,
+          .availableHeight = 0,
+          .widthMeasureMode = (YGMeasureMode)-1,
+          .heightMeasureMode = (YGMeasureMode)-1,
+          .computedWidth = -1,
+          .computedHeight = -1,
+      }),
+      didUseLegacyFlag(false),
+      doesLegacyStretchFlagAffectsLayout(false) {}
+
+bool YGLayout::operator==(YGLayout layout) const {
+  bool isEqual = position == layout.position &&
+      dimensions == layout.dimensions && margin == layout.margin &&
+      border == layout.border && padding == layout.padding &&
+      direction == layout.direction && hadOverflow == layout.hadOverflow &&
+      lastParentDirection == layout.lastParentDirection &&
+      nextCachedMeasurementsIndex == layout.nextCachedMeasurementsIndex &&
+      cachedLayout == layout.cachedLayout;
+
+  for (uint32_t i = 0; i < YG_MAX_CACHED_RESULT_COUNT && isEqual; ++i) {
+    isEqual = isEqual && cachedMeasurements[i] == layout.cachedMeasurements[i];
+  }
+
+  if (!YGFloatIsUndefined(computedFlexBasis) ||
+      !YGFloatIsUndefined(layout.computedFlexBasis)) {
+    isEqual = isEqual && (computedFlexBasis == layout.computedFlexBasis);
+  }
+  if (!YGFloatIsUndefined(measuredDimensions[0]) ||
+      !YGFloatIsUndefined(layout.measuredDimensions[0])) {
+    isEqual =
+        isEqual && (measuredDimensions[0] == layout.measuredDimensions[0]);
+  }
+  if (!YGFloatIsUndefined(measuredDimensions[1]) ||
+      !YGFloatIsUndefined(layout.measuredDimensions[1])) {
+    isEqual =
+        isEqual && (measuredDimensions[1] == layout.measuredDimensions[1]);
+  }
+
+  return isEqual;
+}
+
+bool YGLayout::operator!=(YGLayout layout) const {
+  return !(*this == layout);
+}

yoga/YGLayout.h

@@ -0,0 +1,42 @@
+/**
+ * Copyright (c) 2014-present, 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.
+ */
+#pragma once
+#include "Yoga-internal.h"
+
+struct YGLayout {
+  std::array<float, 4> position;
+  std::array<float, 2> dimensions;
+  std::array<float, 6> margin;
+  std::array<float, 6> border;
+  std::array<float, 6> padding;
+  YGDirection direction;
+
+  uint32_t computedFlexBasisGeneration;
+  float computedFlexBasis;
+  bool hadOverflow;
+
+  // Instead of recomputing the entire layout every single time, we
+  // cache some information to break early when nothing changed
+  uint32_t generationCount;
+  YGDirection lastParentDirection;
+
+  uint32_t nextCachedMeasurementsIndex;
+  std::array<YGCachedMeasurement, YG_MAX_CACHED_RESULT_COUNT>
+      cachedMeasurements;
+  std::array<float, 2> measuredDimensions;
+
+  YGCachedMeasurement cachedLayout;
+  bool didUseLegacyFlag;
+  bool doesLegacyStretchFlagAffectsLayout;
+
+  YGLayout();
+
+  bool operator==(YGLayout layout) const;
+  bool operator!=(YGLayout layout) const;
+};

yoga/YGNode.cpp

@@ -383,7 +383,7 @@ YGNode::YGNode()
       baseline_(nullptr),
       dirtied_(nullptr),
       style_(YGStyle()),
-      layout_(gYGNodeLayoutDefaults),
+      layout_(YGLayout()),
       lineIndex_(0),
       parent_(nullptr),
       children_(YGVector()),

yoga/YGNode.h

@@ -7,6 +7,7 @@
 
 #pragma once
 #include <stdio.h>
+#include "YGLayout.h"
 #include "YGStyle.h"
 #include "Yoga-internal.h"
 

yoga/YGStyle.cpp

@@ -8,6 +8,27 @@
  */
 #include "YGStyle.h"
 
+const YGValue kYGValueUndefined = {YGUndefined, YGUnitUndefined};
+
+const YGValue kYGValueAuto = {YGUndefined, YGUnitAuto};
+
+const std::array<YGValue, YGEdgeCount> kYGDefaultEdgeValuesUnit = {
+    {kYGValueUndefined,
+     kYGValueUndefined,
+     kYGValueUndefined,
+     kYGValueUndefined,
+     kYGValueUndefined,
+     kYGValueUndefined,
+     kYGValueUndefined,
+     kYGValueUndefined,
+     kYGValueUndefined}};
+
+const std::array<YGValue, 2> kYGDefaultDimensionValuesAutoUnit = {
+    {kYGValueAuto, kYGValueAuto}};
+
+const std::array<YGValue, 2> kYGDefaultDimensionValuesUnit = {
+    {kYGValueUndefined, kYGValueUndefined}};
+
 YGStyle::YGStyle()
     : direction(YGDirectionInherit),
       flexDirection(YGFlexDirectionColumn),

yoga/Yoga-internal.h

@@ -41,23 +41,6 @@ bool YGValueArrayEqual(
   return areEqual;
 }
 
-const YGValue kYGValueUndefined = {YGUndefined, YGUnitUndefined};
-const YGValue kYGValueAuto = {YGUndefined, YGUnitAuto};
-const std::array<YGValue, YGEdgeCount> kYGDefaultEdgeValuesUnit = {
-    {kYGValueUndefined,
-     kYGValueUndefined,
-     kYGValueUndefined,
-     kYGValueUndefined,
-     kYGValueUndefined,
-     kYGValueUndefined,
-     kYGValueUndefined,
-     kYGValueUndefined,
-     kYGValueUndefined}};
-const std::array<YGValue, 2> kYGDefaultDimensionValuesAutoUnit = {
-    {kYGValueAuto, kYGValueAuto}};
-const std::array<YGValue, 2> kYGDefaultDimensionValuesUnit = {
-    {kYGValueUndefined, kYGValueUndefined}};
-
 struct YGCachedMeasurement {
   float availableWidth;
   float availableHeight;
@@ -95,68 +78,6 @@ struct YGCachedMeasurement {
 // layouts should not require more than 16 entries to fit within the cache.
 #define YG_MAX_CACHED_RESULT_COUNT 16
 
-struct YGLayout {
-  std::array<float, 4> position;
-  std::array<float, 2> dimensions;
-  std::array<float, 6> margin;
-  std::array<float, 6> border;
-  std::array<float, 6> padding;
-  YGDirection direction;
-
-  uint32_t computedFlexBasisGeneration;
-  float computedFlexBasis;
-  bool hadOverflow;
-
-  // Instead of recomputing the entire layout every single time, we
-  // cache some information to break early when nothing changed
-  uint32_t generationCount;
-  YGDirection lastParentDirection;
-
-  uint32_t nextCachedMeasurementsIndex;
-  YGCachedMeasurement cachedMeasurements[YG_MAX_CACHED_RESULT_COUNT];
-  std::array<float, 2> measuredDimensions;
-
-  YGCachedMeasurement cachedLayout;
-  bool didUseLegacyFlag;
-  bool doesLegacyStretchFlagAffectsLayout;
-
-  bool operator==(YGLayout layout) const {
-    bool isEqual = position == layout.position &&
-        dimensions == layout.dimensions && margin == layout.margin &&
-        border == layout.border && padding == layout.padding &&
-        direction == layout.direction && hadOverflow == layout.hadOverflow &&
-        lastParentDirection == layout.lastParentDirection &&
-        nextCachedMeasurementsIndex == layout.nextCachedMeasurementsIndex &&
-        cachedLayout == layout.cachedLayout;
-
-    for (uint32_t i = 0; i < YG_MAX_CACHED_RESULT_COUNT && isEqual; ++i) {
-      isEqual =
-          isEqual && cachedMeasurements[i] == layout.cachedMeasurements[i];
-    }
-
-    if (!YGFloatIsUndefined(computedFlexBasis) ||
-        !YGFloatIsUndefined(layout.computedFlexBasis)) {
-      isEqual = isEqual && (computedFlexBasis == layout.computedFlexBasis);
-    }
-    if (!YGFloatIsUndefined(measuredDimensions[0]) ||
-        !YGFloatIsUndefined(layout.measuredDimensions[0])) {
-      isEqual =
-          isEqual && (measuredDimensions[0] == layout.measuredDimensions[0]);
-    }
-    if (!YGFloatIsUndefined(measuredDimensions[1]) ||
-        !YGFloatIsUndefined(layout.measuredDimensions[1])) {
-      isEqual =
-          isEqual && (measuredDimensions[1] == layout.measuredDimensions[1]);
-    }
-
-    return isEqual;
-  }
-
-  bool operator!=(YGLayout layout) const {
-    return !(*this == layout);
-  }
-};
-
 struct YGConfig {
   bool experimentalFeatures[YGExperimentalFeatureCount + 1];
   bool useWebDefaults;
@@ -172,34 +93,6 @@ static const float kDefaultFlexGrow = 0.0f;
 static const float kDefaultFlexShrink = 0.0f;
 static const float kWebDefaultFlexShrink = 1.0f;
 
-static const YGLayout gYGNodeLayoutDefaults = {
-    .position = {},
-    .dimensions = {{YGUndefined, YGUndefined}},
-    .margin = {},
-    .border = {},
-    .padding = {},
-    .direction = YGDirectionInherit,
-    .computedFlexBasisGeneration = 0,
-    .computedFlexBasis = YGUndefined,
-    .hadOverflow = false,
-    .generationCount = 0,
-    .lastParentDirection = (YGDirection)-1,
-    .nextCachedMeasurementsIndex = 0,
-    .cachedMeasurements = {},
-    .measuredDimensions = {{YGUndefined, YGUndefined}},
-    .cachedLayout =
-        {
-            .availableWidth = 0,
-            .availableHeight = 0,
-            .widthMeasureMode = (YGMeasureMode)-1,
-            .heightMeasureMode = (YGMeasureMode)-1,
-            .computedWidth = -1,
-            .computedHeight = -1,
-        },
-    .didUseLegacyFlag = false,
-    .doesLegacyStretchFlagAffectsLayout = false,
-};
-
 extern bool YGFloatsEqual(const float a, const float b);
 extern bool YGValueEqual(const YGValue a, const YGValue b);
 extern const YGValue* YGComputedEdgeValue(