Adapt getSelection to use node’s window object

Author: acusti

packages/react-dom/src/client/ReactDOMSelection.js

@@ -16,7 +16,11 @@ var {TEXT_NODE} = require('../shared/HTMLNodeType');
  * @return {?object}
  */
 function getModernOffsets(outerNode) {
-  var selection = window.getSelection && window.getSelection();
+  var win = window;
+  if (outerNode.ownerDocument && outerNode.ownerDocument.defaultView) {
+    win = outerNode.ownerDocument.defaultView;
+  }
+  var selection = win.getSelection && win.getSelection();
 
   if (!selection || selection.rangeCount === 0) {
     return null;
@@ -153,11 +157,16 @@ function getModernOffsetsFromPoints(
  * @param {object} offsets
  */
 function setModernOffsets(node, offsets) {
-  if (!window.getSelection) {
+  var win = window;
+  if (node.ownerDocument && node.ownerDocument.defaultView) {
+    win = node.ownerDocument.defaultView;
+  }
+
+  if (!win.getSelection) {
     return;
   }
 
-  var selection = window.getSelection();
+  var selection = win.getSelection();
   var length = node[getTextContentAccessor()].length;
   var start = Math.min(offsets.start, length);
   var end = offsets.end === undefined ? start : Math.min(offsets.end, length);

packages/react-dom/src/events/SelectEventPlugin.js

@@ -71,14 +71,20 @@ function getSelection(node) {
       start: node.selectionStart,
       end: node.selectionEnd,
     };
-  } else if (window.getSelection) {
-    var selection = window.getSelection();
-    return {
-      anchorNode: selection.anchorNode,
-      anchorOffset: selection.anchorOffset,
-      focusNode: selection.focusNode,
-      focusOffset: selection.focusOffset,
-    };
+  } else {
+    var win = window;
+    if (node.ownerDocument && node.ownerDocument.defaultView) {
+      win = node.ownerDocument.defaultView;
+    }
+    if (win.getSelection) {
+      var selection = win.getSelection();
+      return {
+        anchorNode: selection.anchorNode,
+        anchorOffset: selection.anchorOffset,
+        focusNode: selection.focusNode,
+        focusOffset: selection.focusOffset,
+      };
+    }
   }
 }