1 files changed, 37 insertions, 0 deletions
diff --git a/popperjs/package/lib/dom-utils/getDocumentRect.js.flow b/popperjs/package/lib/dom-utils/getDocumentRect.js.flow
new file mode 100644
index 0000000..c9f63b0
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+++ b/popperjs/package/lib/dom-utils/getDocumentRect.js.flow
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+// @flow
+import type { Rect } from '../types';
+import getDocumentElement from './getDocumentElement';
+import getComputedStyle from './getComputedStyle';
+import getWindowScrollBarX from './getWindowScrollBarX';
+import getWindowScroll from './getWindowScroll';
+import { max } from '../utils/math';
+
+// Gets the entire size of the scrollable document area, even extending outside
+// of the `<html>` and `<body>` rect bounds if horizontally scrollable
+export default function getDocumentRect(element: HTMLElement): Rect {
+  const html = getDocumentElement(element);
+  const winScroll = getWindowScroll(element);
+  const body = element.ownerDocument?.body;
+
+  const width = max(
+    html.scrollWidth,
+    html.clientWidth,
+    body ? body.scrollWidth : 0,
+    body ? body.clientWidth : 0
+  );
+  const height = max(
+    html.scrollHeight,
+    html.clientHeight,
+    body ? body.scrollHeight : 0,
+    body ? body.clientHeight : 0
+  );
+
+  let x = -winScroll.scrollLeft + getWindowScrollBarX(element);
+  const y = -winScroll.scrollTop;
+
+  if (getComputedStyle(body || html).direction === 'rtl') {
+    x += max(html.clientWidth, body ? body.clientWidth : 0) - width;
+  }
+
+  return { width, height, x, y };
+}