add deep equal

Author: ruoru

package-lock.json

@@ -34,6 +34,7 @@
   "homepage": "https://github.com/weui/react-weui",
   "dependencies": {
     "babel-runtime": "^6.18.0",
+    "fast-deep-equal": "^1.0.0",
     "prop-types": "^15.5.10",
     "react": "^16.2.0",
     "react-dom": "^16.2.0",

package.json

@@ -1,6 +1,7 @@
 import React from 'react';
 import PropTypes from 'prop-types';
 import GroupPicker from './group_picker';
+import equal from 'fast-deep-equal';
 
 
 class CascadePicker extends React.Component {
@@ -45,11 +46,13 @@ class CascadePicker extends React.Component {
     }
 
     componentWillReceiveProps(nextProps){
-        const { columns, newSelectIndexs } = this.parseData(nextProps.selectIndexs, nextProps);
-        this.setState({
-            columns,
-            selectIndexs: newSelectIndexs,
-        });
+        if(!equal(this.props.data, nextProps.data)) {
+            const { columns, newSelectIndexs } = this.parseData(nextProps.selectIndexs, nextProps);
+            this.setState({
+                columns,
+                selectIndexs: newSelectIndexs,
+            });
+        }
     }
 
     parseData(selectIndexs = [], props){