1 files changed, 99 insertions, 0 deletions
diff --git a/node_modules/react-dom/lib/EnterLeaveEventPlugin.js b/node_modules/react-dom/lib/EnterLeaveEventPlugin.js
new file mode 100644
index 000000000..9b07d08a6
--- /dev/null
+++ b/node_modules/react-dom/lib/EnterLeaveEventPlugin.js
@@ -0,0 +1,99 @@
+/**
+ * Copyright 2013-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ */
+
+'use strict';
+
+var EventPropagators = require('./EventPropagators');
+var ReactDOMComponentTree = require('./ReactDOMComponentTree');
+var SyntheticMouseEvent = require('./SyntheticMouseEvent');
+
+var eventTypes = {
+  mouseEnter: {
+    registrationName: 'onMouseEnter',
+    dependencies: ['topMouseOut', 'topMouseOver']
+  },
+  mouseLeave: {
+    registrationName: 'onMouseLeave',
+    dependencies: ['topMouseOut', 'topMouseOver']
+  }
+};
+
+var EnterLeaveEventPlugin = {
+
+  eventTypes: eventTypes,
+
+  /**
+   * For almost every interaction we care about, there will be both a top-level
+   * `mouseover` and `mouseout` event that occurs. Only use `mouseout` so that
+   * we do not extract duplicate events. However, moving the mouse into the
+   * browser from outside will not fire a `mouseout` event. In this case, we use
+   * the `mouseover` top-level event.
+   */
+  extractEvents: function (topLevelType, targetInst, nativeEvent, nativeEventTarget) {
+    if (topLevelType === 'topMouseOver' && (nativeEvent.relatedTarget || nativeEvent.fromElement)) {
+      return null;
+    }
+    if (topLevelType !== 'topMouseOut' && topLevelType !== 'topMouseOver') {
+      // Must not be a mouse in or mouse out - ignoring.
+      return null;
+    }
+
+    var win;
+    if (nativeEventTarget.window === nativeEventTarget) {
+      // `nativeEventTarget` is probably a window object.
+      win = nativeEventTarget;
+    } else {
+      // TODO: Figure out why `ownerDocument` is sometimes undefined in IE8.
+      var doc = nativeEventTarget.ownerDocument;
+      if (doc) {
+        win = doc.defaultView || doc.parentWindow;
+      } else {
+        win = window;
+      }
+    }
+
+    var from;
+    var to;
+    if (topLevelType === 'topMouseOut') {
+      from = targetInst;
+      var related = nativeEvent.relatedTarget || nativeEvent.toElement;
+      to = related ? ReactDOMComponentTree.getClosestInstanceFromNode(related) : null;
+    } else {
+      // Moving to a node from outside the window.
+      from = null;
+      to = targetInst;
+    }
+
+    if (from === to) {
+      // Nothing pertains to our managed components.
+      return null;
+    }
+
+    var fromNode = from == null ? win : ReactDOMComponentTree.getNodeFromInstance(from);
+    var toNode = to == null ? win : ReactDOMComponentTree.getNodeFromInstance(to);
+
+    var leave = SyntheticMouseEvent.getPooled(eventTypes.mouseLeave, from, nativeEvent, nativeEventTarget);
+    leave.type = 'mouseleave';
+    leave.target = fromNode;
+    leave.relatedTarget = toNode;
+
+    var enter = SyntheticMouseEvent.getPooled(eventTypes.mouseEnter, to, nativeEvent, nativeEventTarget);
+    enter.type = 'mouseenter';
+    enter.target = toNode;
+    enter.relatedTarget = fromNode;
+
+    EventPropagators.accumulateEnterLeaveDispatches(leave, enter, from, to);
+
+    return [leave, enter];
+  }
+
+};
+
+module.exports = EnterLeaveEventPlugin;
+\ No newline at end of file