diff --git a/networks.rkt b/networks.rkt
index 4080eab..b690510 100644
--- a/networks.rkt
+++ b/networks.rkt
@@ -939,9 +939,10 @@
   (apply-tbf tbf (list->vector (hash-map st (λ (_ val) val)))))
 
 (module+ test
-  (define st (make-state '((x1 . 0) (x2 . 1))))
-  (define f (tbf #(1 1) 1))
-  (check-equal? (apply-tbf-to-state f st) 0))
+  (test-case "apply-tbf-to-state"
+    (define st (make-state '((x1 . 0) (x2 . 1))))
+    (define f (tbf #(1 1) 1))
+    (check-equal? (apply-tbf-to-state f st) 0)))
 
 ;;; A state TBF is a TBF with named inputs.  A state TBF can be
 ;;; applied to states in an unambiguous ways.