Ext version tested:
  • Sencha

Browser versions tested against:

OS X Chrome (latest)
Safari IOS

DOCTYPE tested against:


This is a bit involved, but it seems that Writer.js doesn't know how to deal with null values for dates when dealing with my proxy.

If I try to sync a record that has a particular value for a date (which is optional on my back-end), the code works fine. However, when trying to sync a record that does not have a date in this field, the error occurs.

Steps to reproduce the problem:

* Read some records from JSON with dates...some dates should be filled, some null
* Write a record with a null date

Test Case:

Here's my model definition...if I get back a 'null' value for 'due_date', then try to write that record again is where the bug happens.

Ext.define('CbMobile.model.LineItem', {
  extend: '',
  labelCodes: [
  config: {
    fields: [
      {name:'id', type:'int'},
      {name:'comments_count', type:'int'},
      {name:'created_on', type:'date', dateFormat:'c'},
      {name:'description', type:'string'},
      {name:'due_date', type:'date', dateFormat:'c'},
      {name:'estimate_id', type:'int'},
      {name:'flat_fee', type:'float'},
      {name:'invoice_line_items_count', type:'int'},
      {name:'is_complete', type:'boolean'},
      {name:'is_taxable', type:'boolean'},
      {name:'label_code', type:'int'},
      {name:'markup_percentage', type:'float'},
      {name:'person_id', type:'int'},
      {name:'price_actual', type:'float'},
      {name:'price_per', type:'float'},
      {name:'project_id', type:'int'},
      {name:'project_list_id', type:'int'},
      {name:'quantity_low', type:'float'},
      {name:'quantity_high', type:'float'},
      {name:'rank', type:'int'},
      {name:'time_entry_minutes', type:'int'},
      {name:'title', type:'string'},
      {name:'type_code', type:'int'},
      {name:'unit_label', type:'string'},
      {name:'updated_at', type:'date', dateFormat:'c'}
    validations: []
  labelColor: function() {
    return this.labelCodes[this.get('label_code')];
  isComplete: function() {
    return (this.get('is_complete') == true);
  toggleCompletion: function() {
    this.set('is_complete', !this.isComplete());


I've attached a screenshot of the error trace from the Chrome javascript console.

Screen shot 2012-08-30 at 10.45.49 PM.png