Tab highlight issue

I’m new to Ionic and trying to use the ion-tabs with the sample.

But seems meet a issue.

Here’s my suitation:

have a tabs abstract state with url “/tabs” and anther two states :
tabs.home with url "/home"
tabs.contact with url “/contact”.

Now if i change the tabs.contac’s url to “/hom”. Then when trying to load the tabs. the tab corresponding to tabs.contact will be highlighted.

You can take a look at this codepen: http://codepen.io/fantasybei/pen/QbLbZN/

Is it a bug or do i did something wrong?

Thanks.