From 2feca00797d2c5e7738b31decd56e4025f471226 Mon Sep 17 00:00:00 2001
From: David Vacca <dvacca@fb.com>
Date: Thu, 30 Sep 2021 10:15:25 -0700
Subject: [PATCH] Toggle ScrollView.snapToAlignment behavior using
 ReactFeatureFlag.enableScrollViewSnapToAlignmentProp

Summary:
This diff enables/disables ScrollView.snapToAlignment behavior using ReactFeatureFlag.enableScrollViewSnapToAlignmentProp

changelog: [internal] internal

Reviewed By: motiz88

Differential Revision: D31308300

fbshipit-source-id: 26c01a342cac822f21d83e3474b529bea154aba6
---
 .../react/views/scroll/ReactHorizontalScrollView.java      | 7 +++++--
 .../com/facebook/react/views/scroll/ReactScrollView.java   | 7 +++++--
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactHorizontalScrollView.java b/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactHorizontalScrollView.java
index 69c2a633a42..82099cb25b6 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactHorizontalScrollView.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactHorizontalScrollView.java
@@ -7,6 +7,7 @@
 
 package com.facebook.react.views.scroll;
 
+import static com.facebook.react.config.ReactFeatureFlags.enableScrollViewSnapToAlignmentProp;
 import static com.facebook.react.views.scroll.ReactScrollViewHelper.SNAP_ALIGNMENT_CENTER;
 import static com.facebook.react.views.scroll.ReactScrollViewHelper.SNAP_ALIGNMENT_DISABLED;
 import static com.facebook.react.views.scroll.ReactScrollViewHelper.SNAP_ALIGNMENT_END;
@@ -916,7 +917,9 @@ public class ReactHorizontalScrollView extends HorizontalScrollView
     }
 
     // pagingEnabled only allows snapping one interval at a time
-    if (mSnapInterval == 0 && mSnapOffsets == null && mSnapToAlignment == SNAP_ALIGNMENT_DISABLED) {
+    if (mSnapInterval == 0
+        && mSnapOffsets == null
+        && (!enableScrollViewSnapToAlignmentProp || mSnapToAlignment == SNAP_ALIGNMENT_DISABLED)) {
       smoothScrollAndSnap(velocityX);
       return;
     }
@@ -959,7 +962,7 @@ public class ReactHorizontalScrollView extends HorizontalScrollView
           }
         }
       }
-    } else if (mSnapToAlignment != SNAP_ALIGNMENT_DISABLED) {
+    } else if (enableScrollViewSnapToAlignmentProp && mSnapToAlignment != SNAP_ALIGNMENT_DISABLED) {
       if (mSnapInterval > 0) {
         double ratio = (double) targetOffset / mSnapInterval;
         smallerOffset =
diff --git a/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactScrollView.java b/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactScrollView.java
index bb9dc676499..3b920a6f505 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactScrollView.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactScrollView.java
@@ -7,6 +7,7 @@
 
 package com.facebook.react.views.scroll;
 
+import static com.facebook.react.config.ReactFeatureFlags.enableScrollViewSnapToAlignmentProp;
 import static com.facebook.react.views.scroll.ReactScrollViewHelper.SNAP_ALIGNMENT_CENTER;
 import static com.facebook.react.views.scroll.ReactScrollViewHelper.SNAP_ALIGNMENT_DISABLED;
 import static com.facebook.react.views.scroll.ReactScrollViewHelper.SNAP_ALIGNMENT_END;
@@ -704,7 +705,9 @@ public class ReactScrollView extends ScrollView
     }
 
     // pagingEnabled only allows snapping one interval at a time
-    if (mSnapInterval == 0 && mSnapOffsets == null && mSnapToAlignment == SNAP_ALIGNMENT_DISABLED) {
+    if (mSnapInterval == 0
+        && mSnapOffsets == null
+        && (!enableScrollViewSnapToAlignmentProp || mSnapToAlignment == SNAP_ALIGNMENT_DISABLED)) {
       smoothScrollAndSnap(velocityY);
       return;
     }
@@ -742,7 +745,7 @@ public class ReactScrollView extends ScrollView
         }
       }
 
-    } else if (mSnapToAlignment != SNAP_ALIGNMENT_DISABLED) {
+    } else if (enableScrollViewSnapToAlignmentProp && mSnapToAlignment != SNAP_ALIGNMENT_DISABLED) {
       if (mSnapInterval > 0) {
         double ratio = (double) targetOffset / mSnapInterval;
         smallerOffset =