From ecd5829bf8d5c884913317ee0197f49251703a11 Mon Sep 17 00:00:00 2001
From: Andrey Mishanin <amishanin@fb.com>
Date: Fri, 30 Jun 2017 09:19:33 -0700
Subject: [PATCH] Overflow detection in Yoga

Reviewed By: gkassabli

Differential Revision: D5336645

fbshipit-source-id: c4f87d1754d7bac848e8d347b31d619393b94d2c
---
 ReactCommon/yoga/yoga/Yoga.c | 5 +++++
 ReactCommon/yoga/yoga/Yoga.h | 1 +
 2 files changed, 6 insertions(+)

diff --git a/ReactCommon/yoga/yoga/Yoga.c b/ReactCommon/yoga/yoga/Yoga.c
index b94692635..aba42c7d4 100644
--- a/ReactCommon/yoga/yoga/Yoga.c
+++ b/ReactCommon/yoga/yoga/Yoga.c
@@ -54,6 +54,7 @@ typedef struct YGLayout {
 
   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
@@ -192,6 +193,7 @@ static YGNode gYGNodeDefaults = {
             .lastParentDirection = (YGDirection) -1,
             .nextCachedMeasurementsIndex = 0,
             .computedFlexBasis = YGUndefined,
+            .hadOverflow = false,
             .measuredDimensions = YG_DEFAULT_DIMENSION_VALUES,
 
             .cachedLayout =
@@ -782,6 +784,7 @@ YG_NODE_LAYOUT_PROPERTY_IMPL(float, Bottom, position[YGEdgeBottom]);
 YG_NODE_LAYOUT_PROPERTY_IMPL(float, Width, dimensions[YGDimensionWidth]);
 YG_NODE_LAYOUT_PROPERTY_IMPL(float, Height, dimensions[YGDimensionHeight]);
 YG_NODE_LAYOUT_PROPERTY_IMPL(YGDirection, Direction, direction);
+YG_NODE_LAYOUT_PROPERTY_IMPL(bool, HadOverflow, hadOverflow);
 
 YG_NODE_LAYOUT_RESOLVED_PROPERTY_IMPL(float, Margin, margin);
 YG_NODE_LAYOUT_RESOLVED_PROPERTY_IMPL(float, Border, border);
@@ -2574,12 +2577,14 @@ static void YGNodelayoutImpl(const YGNodeRef node,
                              performLayout && !requiresStretchLayout,
                              "flex",
                              config);
+        node->layout.hadOverflow = node->layout.hadOverflow || currentRelativeChild->layout.hadOverflow;
 
         currentRelativeChild = currentRelativeChild->nextChild;
       }
     }
 
     remainingFreeSpace = originalRemainingFreeSpace + deltaFreeSpace;
+    node->layout.hadOverflow = node->layout.hadOverflow || (remainingFreeSpace < 0);
 
     // STEP 6: MAIN-AXIS JUSTIFICATION & CROSS-AXIS SIZE DETERMINATION
 
diff --git a/ReactCommon/yoga/yoga/Yoga.h b/ReactCommon/yoga/yoga/Yoga.h
index 3579941ce..c3d3260d3 100644
--- a/ReactCommon/yoga/yoga/Yoga.h
+++ b/ReactCommon/yoga/yoga/Yoga.h
@@ -215,6 +215,7 @@ YG_NODE_LAYOUT_PROPERTY(float, Bottom);
 YG_NODE_LAYOUT_PROPERTY(float, Width);
 YG_NODE_LAYOUT_PROPERTY(float, Height);
 YG_NODE_LAYOUT_PROPERTY(YGDirection, Direction);
+YG_NODE_LAYOUT_PROPERTY(bool, HadOverflow);
 
 // Get the computed values for these nodes after performing layout. If they were set using
 // point values then the returned value will be the same as YGNodeStyleGetXXX. However if