Programmer - Rails image_tag not closing image tag

Programmer Question

On a rails project I am using the image_tag to generate my image html elements.

<%= image_tag("test.jpg", :alt => "test image") %>

is generating

<img src="test.jpg" alt="test image">

This is happening throughout my entire rails project.

Is there a setting somewhere that someone else set that is causing this?
How can I get rails to always close the image tag?