From 1ac17ad9566008145e89d06b807cfae6e8f29788 Mon Sep 17 00:00:00 2001
From: jbphet <john.blanco@colorado.edu>
Date: Tue, 16 Mar 2021 12:30:34 -0600
Subject: [PATCH] pointers valid until end of onRelease, see
 https://github.com/phetsims/joist/issues/689

---
 js/listeners/PressListener.js | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/js/listeners/PressListener.js b/js/listeners/PressListener.js
index 830206e5a..d7ae89092 100644
--- a/js/listeners/PressListener.js
+++ b/js/listeners/PressListener.js
@@ -193,11 +193,15 @@ class PressListener {
     // @public {Property.<boolean>} (read-only) - Whether the listener has focus (should appear to be over)
     this.isFocusedProperty = new BooleanProperty( false );
 
-    // @public {Pointer|null} (read-only) - The current pointer, or null when not pressed.
+    // @public {Pointer|null} (read-only) - The current pointer, or null when not pressed. There can be short periods of
+    // time when this has a value when isPressedProperty.value is false, such as during the processing of a pointer
+    // release, but these periods should be very brief.
     this.pointer = null;
 
     // @public {Trail|null} (read-only) - The Trail for the press, with no descendant nodes past the currentTarget
-    // or targetNode (if provided). Will be null when not pressed.
+    // or targetNode (if provided). Will generally be null when not pressed, though there can be short periods of time
+    // where this has a value when isPressedProperty.value is false, such as during the processing of a release, but
+    // these periods should be very brief.
     this.pressedTrail = null;
 
     // @public {boolean} (read-only) - Whether the last press was interrupted. Will be valid until the next press.
@@ -632,18 +636,20 @@ class PressListener {
     this.pointer.removeInputListener( this._pointerListener );
     this._listeningToPointer = false;
 
-    this.pointer.cursor = null;
-
-    // Unset this properties after the property change, so they are visible to listeners beforehand.
-    this.pointer = null;
-    this.pressedTrail = null;
-
+    // Set the pressed state false *before* invoking the callback, otherwise an infinite loop can result in some
+    // circumstances.
     this.isPressedProperty.value = false;
 
     // Notify after the rest of release is called in order to prevent it from triggering interrupt().
     this._releaseListener( event, this );
 
     callback && callback();
+
+    // Unset these properties after the Property value change and after invoking the callbacks so that they can be
+    // referenced.
+    this.pointer.cursor = null;
+    this.pointer = null;
+    this.pressedTrail = null;
   }
 
   /**