diff --git a/collects/tests/gracket/racket-ns.rkt b/collects/tests/gracket/racket-ns.rkt
index 85b065ee..234df242 100644
--- a/collects/tests/gracket/racket-ns.rkt
+++ b/collects/tests/gracket/racket-ns.rkt
@@ -6,4 +6,6 @@
 
 (let ([ns ((gui-dynamic-require 'make-gui-namespace))]
       [orig-ns (current-namespace)])
+  (unless (namespace-variable-value 'hash #t (lambda () #f) ns)
+    (error "expected a binding for `hash'"))
   (namespace-attach-module orig-ns 'racket/base ns))
diff --git a/collects/tests/gracket/scheme-ns.rkt b/collects/tests/gracket/scheme-ns.rkt
index 2c445ba9..17ea5953 100644
--- a/collects/tests/gracket/scheme-ns.rkt
+++ b/collects/tests/gracket/scheme-ns.rkt
@@ -6,4 +6,6 @@
 
 (let ([ns ((gui-dynamic-require 'make-gui-namespace))]
       [orig-ns (current-namespace)])
+  (when (namespace-variable-value 'hash #t (lambda () #f) ns)
+    (error "did not expect a binding for `hash'"))
   (namespace-attach-module orig-ns 'scheme/base ns))