You can download the extension here:
NavigateToTest Visual Studio 2012 extension
Some time ago I blogged about the GoToTest macro and VS2010 navigate to test extension
Here’s the latest version that supports Visual Studio 2012.
Extension is convention based. It matches ClassName file with ClassNameTest or ClassNameTests and vice-versa, so you can easily navigate to the test file and back.
Here are some screenshots:
Here’s the toolbar and two opened files:
You can download the extension here:
NavigateToTest Visual Studio 2012 extension