I have been coding without asserts Windows store application in javascript (WinJS based). Amidst making progress on frameworks for the next application, looking into this was at the back burner. One day, it pinched enough to look around for the solution.

I had been using chai.js for the assertions in the nodejs server code. It is expected to work in browser. hence, gave it a try to use it in WinJS application. It works; the library has right set of apis for the assertions in javascript.

What needs to be done:

1. download chai.js for browser from here.
2. Add the file to the vs project
3. Add script entry into default.html
4. Add a global variable – assert – in default.js
5. Use the assert apis in code.

default.html:

<!-- WinJS references -->     
<link href="//Microsoft.WinJS.1.0/css/ui-dark.css" rel="stylesheet" />     
<script src="//Microsoft.WinJS.1.0/js/base.js"></script>     
<script src="//Microsoft.WinJS.1.0/js/ui.js"></script>

<!-- external js libs -->     
<script src="/js/chai.js"></script>

<script src="/js/default.js"></script>

default.js:

 
(function()
{
    ...
    assert = chai.assert;
})();
var assert;

Examples:

 
    assert.isObject(this.options);

    assert.isString(this.options.parameter1);

    assert.deepEqual({ tea: 'tea' }, { tea: 'tea' });
    //  for more examples - refer http://chaijs.com/api/assert/