From 941353f62152f1cdb37aa5f12613597c087ae486 Mon Sep 17 00:00:00 2001
From: Mike Reinstein <mreinstein@sellpoints.com>
Date: Sun, 31 May 2020 11:44:18 -0700
Subject: [PATCH] add some documentation on getOffsetParent and
 listScrollParents

---
 src/dom-utils/getOffsetParent.js   | 4 ++++
 src/dom-utils/listScrollParents.js | 6 ++++++
 2 files changed, 10 insertions(+)

diff --git a/src/dom-utils/getOffsetParent.js b/src/dom-utils/getOffsetParent.js
index bd2ed5026f..513793f7a8 100644
--- a/src/dom-utils/getOffsetParent.js
+++ b/src/dom-utils/getOffsetParent.js
@@ -17,6 +17,10 @@ function getTrueOffsetParent(element: Element): ?Element {
   return element.offsetParent;
 }
 
+/*
+get the closest ancestor positioned element. Handles some edge cases,
+such as table ancestors and cross browser bugs.
+*/
 export default function getOffsetParent(element: Element) {
   const window = getWindow(element);
 
diff --git a/src/dom-utils/listScrollParents.js b/src/dom-utils/listScrollParents.js
index 49a00d0ddc..9af1dd6950 100644
--- a/src/dom-utils/listScrollParents.js
+++ b/src/dom-utils/listScrollParents.js
@@ -6,6 +6,12 @@ import getWindow from './getWindow';
 import type { Window, VisualViewport } from '../types';
 import isScrollParent from './isScrollParent';
 
+/*
+given a DOM element, return the list of all scroll parents, up the list of ancesors
+until we get to the top window object. This list is what we attach scroll listeners
+to, because if any of these parent elements scroll, we'll need to re-calculate the 
+reference element's position.
+*/
 export default function listScrollParents(
   element: Node,
   list: Array<Element | Window> = []