1 files changed, 15 insertions, 0 deletions
diff --git a/popperjs/package/lib/dom-utils/getDocumentElement.js.flow b/popperjs/package/lib/dom-utils/getDocumentElement.js.flow
new file mode 100644
index 0000000..ad6fa5f
--- /dev/null
+++ b/popperjs/package/lib/dom-utils/getDocumentElement.js.flow
@@ -0,0 +1,15 @@
+// @flow
+import { isElement } from './instanceOf';
+import type { Window } from '../types';
+
+export default function getDocumentElement(
+  element: Element | Window
+): HTMLElement {
+  // $FlowFixMe[incompatible-return]: assume body is always available
+  return (
+    (isElement(element)
+      ? element.ownerDocument
+      : // $FlowFixMe[prop-missing]
+        element.document) || window.document
+  ).documentElement;
+}