Observers not firing when running a single Rails 4 test

[homerlex]

I'm in the process of upgrading out Rails 3.2 app to Rails 4.1.5. When I run the full test suite (rake test) teh observer callbacks are fired. However, when I try to run a single test (rake test TEST=somefile.rb) the observer callbacks are not fire.

Any idea why this would be? I do not see the same behavior in Rails 3.2

[diazruy]

Also happening on Rails 5.0.3