From 671c6ac04e54899738f328aecb75fd88bb245484 Mon Sep 17 00:00:00 2001
From: Georgiy Kassabli <gkassabli@fb.com>
Date: Wed, 26 Jul 2017 19:22:03 -0700
Subject: [PATCH] Fixing edge case issue in Yoga where text node was
 unnecessary rounded down

Reviewed By: emilsjolander

Differential Revision: D5465632

fbshipit-source-id: 57e11092a97eba5dd76daad15fa8619535ff9c1b
---
 ReactCommon/yoga/yoga/Yoga-internal.h | 19 +++++++++++++++++++
 ReactCommon/yoga/yoga/Yoga.c          |  9 +++++++--
 2 files changed, 26 insertions(+), 2 deletions(-)
 create mode 100644 ReactCommon/yoga/yoga/Yoga-internal.h

diff --git a/ReactCommon/yoga/yoga/Yoga-internal.h b/ReactCommon/yoga/yoga/Yoga-internal.h
new file mode 100644
index 000000000..7689b9257
--- /dev/null
+++ b/ReactCommon/yoga/yoga/Yoga-internal.h
@@ -0,0 +1,19 @@
+/**
+ * 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
+
+YG_EXTERN_C_BEGIN
+
+WIN_EXPORT float YGRoundValueToPixelGrid(const float value,
+                                         const float pointScaleFactor,
+                                         const bool forceCeil,
+                                         const bool forceFloor);
+
+YG_EXTERN_C_END
diff --git a/ReactCommon/yoga/yoga/Yoga.c b/ReactCommon/yoga/yoga/Yoga.c
index 398d37749..ab2ef2355 100644
--- a/ReactCommon/yoga/yoga/Yoga.c
+++ b/ReactCommon/yoga/yoga/Yoga.c
@@ -11,6 +11,7 @@
 
 #include "YGNodeList.h"
 #include "Yoga.h"
+#include "Yoga-internal.h"
 
 #ifdef _MSC_VER
 #include <float.h>
@@ -3158,20 +3159,24 @@ static inline bool YGMeasureModeNewMeasureSizeIsStricterAndStillValid(YGMeasureM
          lastSize > size && (lastComputedSize <= size || YGFloatsEqual(size, lastComputedSize));
 }
 
-static float YGRoundValueToPixelGrid(const float value,
+float YGRoundValueToPixelGrid(const float value,
                                      const float pointScaleFactor,
                                      const bool forceCeil,
                                      const bool forceFloor) {
   float scaledValue = value * pointScaleFactor;
   float fractial = fmodf(scaledValue, 1.0);
   if (YGFloatsEqual(fractial, 0)) {
-    // Still remove fractial as fractial could be  extremely small.
+    // First we check if the value is already rounded
     scaledValue = scaledValue - fractial;
+  } else if (YGFloatsEqual(fractial, 1.0)) {
+    scaledValue = scaledValue - fractial + 1.0;
   } else if (forceCeil) {
+    // Next we check if we need to use forced rounding
     scaledValue = scaledValue - fractial + 1.0;
   } else if (forceFloor) {
     scaledValue = scaledValue - fractial;
   } else {
+    // Finally we just round the value
     scaledValue = scaledValue - fractial + (fractial >= 0.5f ? 1.0 : 0);
   }
   return scaledValue / pointScaleFactor;