Fixed EXDEV issue in NW apps

lib/datastore.js

@@ -560,6 +560,6 @@ Datastore.prototype._remove = function (query, options, cb) {
 Datastore.prototype.remove = function () {
   this.executor.push({ this: this, fn: this._remove, arguments: arguments });
 };
-      
+
 
 module.exports = Datastore;

lib/persistence.js

@@ -37,7 +37,16 @@ function Persistence (options) {
 
   // For NW apps, store data in the same directory where NW stores application data
   if (this.filename && options.nodeWebkitAppName) {
+    console.log("==================================================================");
+    console.log("WARNING: The nodeWebkitAppName option is deprecated");
+    console.log("To get the path to the directory where Node Webkit stores the data");
+    console.log("for your app, use the internal nw.gui module like this");
+    console.log("require('nw.gui').App.dataPath");
+    console.log("See https://github.com/rogerwang/node-webkit/issues/500");
+    console.log("==================================================================");
     this.filename = Persistence.getNWAppFilename(options.nodeWebkitAppName, this.filename);
+    this.tempFilename = Persistence.getNWAppFilename(options.nodeWebkitAppName, this.tempFilename);
+    this.oldFilename = Persistence.getNWAppFilename(options.nodeWebkitAppName, this.oldFilename);
   }
 };