Merge pull request #84 from josebalius/master

Fix for issue #83 - JSONObjectNode#getChildNodes: Cannot read propert…

Author: gaearon

src/react/JSONTree/JSONArrayNode.js

@@ -58,7 +58,7 @@ export default class JSONArrayNode extends React.Component {
       let childNodes = [];
       this.props.data.forEach((element, idx) => {
         let prevData;
-        if (typeof this.props.previousData !== 'undefined') {
+        if (typeof this.props.previousData !== 'undefined' && this.props.previousData !== null) {
           prevData = this.props.previousData[idx];
         }
         const node = grabNode(idx, element, prevData, this.props.theme);

src/react/JSONTree/JSONIterableNode.js

@@ -67,7 +67,7 @@ export default class JSONIterableNode extends React.Component {
         }
 
         let prevData;
-        if (typeof this.props.previousData !== 'undefined') {
+        if (typeof this.props.previousData !== 'undefined' && this.props.previousData !== null) {
           prevData = this.props.previousData[key];
         }
         const node = grabNode(key, value, prevData, this.props.theme);

src/react/JSONTree/JSONObjectNode.js

@@ -58,7 +58,7 @@ export default class JSONObjectNode extends React.Component {
       for (let k in obj) {
         if (obj.hasOwnProperty(k)) {
           let prevData;
-          if (typeof this.props.previousData !== 'undefined') {
+          if (typeof this.props.previousData !== 'undefined' && this.props.previousData !== null) {
             prevData = this.props.previousData[k];
           }
           const node = grabNode(k, obj[k], prevData, this.props.theme);