From cd16a0b20d84b21716df41bdf148ad0336b31bd9 Mon Sep 17 00:00:00 2001
From: baiyaaaaa <bigpet1991@gmail.com>
Date: Sat, 5 Nov 2016 12:12:40 +0800
Subject: [PATCH] fix ie9/10 bounding top bug

---
 src/utils/popper.js | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/utils/popper.js b/src/utils/popper.js
index 20299d407..b3b904936 100644
--- a/src/utils/popper.js
+++ b/src/utils/popper.js
@@ -1148,13 +1148,22 @@
      */
     function getBoundingClientRect(element) {
         var rect = element.getBoundingClientRect();
+
+        // whether the IE version is lower than 11
+        var isIE = navigator.userAgent.indexOf("MSIE") != -1;
+
+        // fix ie document bouding top always 0 bug
+        var rectTop = isIE && element.tagName === 'HTML'
+            ? -element.scrollTop
+            : rect.top;
+
         return {
             left: rect.left,
-            top: rect.top,
+            top: rectTop,
             right: rect.right,
             bottom: rect.bottom,
             width: rect.right - rect.left,
-            height: rect.bottom - rect.top
+            height: rect.bottom - rectTop
         };
     }