1 files changed, 26 insertions, 0 deletions
diff --git a/popperjs/package/lib/dom-utils/listScrollParents.js b/popperjs/package/lib/dom-utils/listScrollParents.js
new file mode 100644
index 0000000..24e8bd2
--- /dev/null
+++ b/popperjs/package/lib/dom-utils/listScrollParents.js
@@ -0,0 +1,26 @@
+import getScrollParent from "./getScrollParent.js";
+import getParentNode from "./getParentNode.js";
+import getWindow from "./getWindow.js";
+import isScrollParent from "./isScrollParent.js";
+/*
+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, list) {
+  var _element$ownerDocumen;
+
+  if (list === void 0) {
+    list = [];
+  }
+
+  var scrollParent = getScrollParent(element);
+  var isBody = scrollParent === ((_element$ownerDocumen = element.ownerDocument) == null ? void 0 : _element$ownerDocumen.body);
+  var win = getWindow(scrollParent);
+  var target = isBody ? [win].concat(win.visualViewport || [], isScrollParent(scrollParent) ? scrollParent : []) : scrollParent;
+  var updatedList = list.concat(target);
+  return isBody ? updatedList : // $FlowFixMe[incompatible-call]: isBody tells us target will be an HTMLElement here
+  updatedList.concat(listScrollParents(getParentNode(target)));
+}
+\ No newline at end of file