From d666eb7a2205ed4bd69bd27029c61ed3457ef49f Mon Sep 17 00:00:00 2001
From: Luna Wei <luwe@fb.com>
Date: Fri, 24 Jun 2022 15:10:50 -0700
Subject: [PATCH] Fix: PointerEvent filtering

Summary:
Changelog: [Internal] - Fix a bug in dispatch filtering that was too aggressively filtering out events to fire.

My flaw in logic was limiting the `isListening(view, bubble)` logic to `i==0` for relevant `ViewTargets`, when in reality, we need to be checking if every `ViewTarget` passed to `filterByShouldDispatch` is listening to a bubble event.

Further, as vincentriemer pointed out, `ancestorListening` should only be set true if a `ViewTarget` is listening to a capture event.

Reviewed By: vincentriemer

Differential Revision: D37423952

fbshipit-source-id: 2ed08038632677c24766bca6214dc00013fa2446
---
 .../react/uimanager/JSPointerDispatcher.java  | 20 +++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/ReactAndroid/src/main/java/com/facebook/react/uimanager/JSPointerDispatcher.java b/ReactAndroid/src/main/java/com/facebook/react/uimanager/JSPointerDispatcher.java
index 935941d60e6..71b9a6be59d 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/uimanager/JSPointerDispatcher.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/uimanager/JSPointerDispatcher.java
@@ -249,28 +249,32 @@ public class JSPointerDispatcher {
    * Returns list of view targets that we should be dispatching events from
    *
    * @param viewTargets, ordered from target -> root
-   * @param bubble, name of event that bubbles
-   * @param capture, name of event that captures
+   * @param bubble, name of event that bubbles. Should only ever be enter or leave
+   * @param capture, name of event that captures. Should only ever be enter or leave
    * @param forceDispatch, if true, all viewTargets should dispatch
    * @return list of viewTargets filtered from target -> root
    */
   private static List<ViewTarget> filterByShouldDispatch(
       List<ViewTarget> viewTargets, EVENT bubble, EVENT capture, boolean forceDispatch) {
+
+    List<ViewTarget> dispatchableViewTargets = new ArrayList<>(viewTargets);
     if (forceDispatch) {
-      return viewTargets;
+      return dispatchableViewTargets;
     }
 
     boolean ancestorListening = false;
-    List<ViewTarget> dispatchableViewTargets = new ArrayList<ViewTarget>(viewTargets);
+
+    // Start to filter which viewTargets may not need to dispatch an event
     for (int i = viewTargets.size() - 1; i >= 0; i--) {
       ViewTarget viewTarget = viewTargets.get(i);
       View view = viewTarget.getView();
+
       if (!ancestorListening
-          && (PointerEventHelper.isListening(view, capture)
-              || (i == 0 && PointerEventHelper.isListening(view, bubble)))) {
-        ancestorListening = true;
-      } else if (!ancestorListening) {
+          && !PointerEventHelper.isListening(view, capture)
+          && !PointerEventHelper.isListening(view, bubble)) {
         dispatchableViewTargets.remove(i);
+      } else if (!ancestorListening && PointerEventHelper.isListening(view, capture)) {
+        ancestorListening = true;
       }
     }
     return dispatchableViewTargets;