WIP - moving finagle-kestrel to ScalaTest

So, I did manage to port all tests to ScalaTests. But I understand that I messed up collections assertions in the process. I'm guessing I don't quite understand how lazy collections work in Scala.
What's really weird, when I tried to figure it out, the same tests that fail with assert on collections worked fine when I replaced assert with should equal (BDD style).
Would anyone be so kind to point me in the right direction on these?