From 32739afcc1db1997a887dfba7bc6b45b9b7e3e87 Mon Sep 17 00:00:00 2001
From: David Aurelio <davidaurelio@fb.com>
Date: Mon, 8 Apr 2019 03:16:53 -0700
Subject: [PATCH] Fix bugs around `align-content`
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Summary:
@public

Regenerating the “golden master” tests with chrome surfaced different bugs around `align-content`:

- a misunderstanding that values in `align-content` only applied *if there is only one line.* In fact, it applies *every time* a container is set to `flex-wrap: wrap`. Chrome had this wrong, and as such our tests were generated with incorrect parameters.
- empty children growing to the cross axis size of the container, even when `align-content` is different from `stretch`. This was implemented incorrectly in Chrome as well. Here, we fix it with an extra check.

Reviewed By: SidharthGuglani

Differential Revision: D14725402

fbshipit-source-id: a45bebdadb9c694dc0eb7e27cb52b3d247f81c50
---
 ReactCommon/yoga/yoga/Yoga.cpp | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/ReactCommon/yoga/yoga/Yoga.cpp b/ReactCommon/yoga/yoga/Yoga.cpp
index 8190399125d..431a59a888a 100644
--- a/ReactCommon/yoga/yoga/Yoga.cpp
+++ b/ReactCommon/yoga/yoga/Yoga.cpp
@@ -3089,12 +3089,19 @@ static void YGNodelayoutImpl(
               const float childHeight =
                   !isMainAxisRow ? childMainSize : childCrossSize;
 
+              auto alignContent = node->getStyle().alignContent;
+              auto crossAxisDoesNotGrow =
+                  alignContent != YGAlignStretch && isNodeFlexWrap;
               const YGMeasureMode childWidthMeasureMode =
-                  YGFloatIsUndefined(childWidth) ? YGMeasureModeUndefined
-                                                 : YGMeasureModeExactly;
+                  YGFloatIsUndefined(childWidth) ||
+                      (!isMainAxisRow && crossAxisDoesNotGrow)
+                  ? YGMeasureModeUndefined
+                  : YGMeasureModeExactly;
               const YGMeasureMode childHeightMeasureMode =
-                  YGFloatIsUndefined(childHeight) ? YGMeasureModeUndefined
-                                                  : YGMeasureModeExactly;
+                  YGFloatIsUndefined(childHeight) ||
+                      (isMainAxisRow && crossAxisDoesNotGrow)
+                  ? YGMeasureModeUndefined
+                  : YGMeasureModeExactly;
 
               YGLayoutNodeInternal(
                   child,
@@ -3148,7 +3155,7 @@ static void YGNodelayoutImpl(
 
   // STEP 8: MULTI-LINE CONTENT ALIGNMENT
   // currentLead stores the size of the cross dim
-  if (performLayout && (lineCount > 1 || YGIsBaselineLayout(node))) {
+  if (performLayout && (isNodeFlexWrap || YGIsBaselineLayout(node))) {
     float crossDimLead = 0;
     float currentLead = leadingPaddingAndBorderCross;
     if (!YGFloatIsUndefined(availableInnerCrossDim)) {