added a drracket test

collects/tests/drracket/teaching-lang-sharing-modules.rkt

@@ -0,0 +1,48 @@
+#lang racket
+(require "drracket-test-util.rkt")
+
+#|
+
+This test checks to see if the code that htdp-lang.rkt injects
+into the teaching languages relies only on modules that are
+shared between drracket's and the teaching langauges's namespace.
+
+In practice when this test fails it means that some code in
+langs/htdp-lang.rkt has something like #'(f) for some function
+f that is intended to be eval'd in the teaching languages and 
+it should instead have #'(#%plain-app f). In that case, this
+test fails because the #'(f) is reall #'(#%app f) which uses
+the application form from racket/base and that #%app macro
+is not there in the teaching languages (since the modules
+implementing it are not being shared, you get a different instance
+of that macro, tho; one that triggers an error).
+
+Of course, other (similar) things can go wrong, too.
+
+|#
+
+(fire-up-drscheme-and-run-tests
+ (λ ()
+   (putenv "PLTDRHTDPNOCOMPILED" "yes")
+   (define drs-frame (wait-for-drscheme-frame))
+   (set-language-level! '("How to Design Programs" "Beginning Student"))
+   (clear-definitions drs-frame)
+   (type-in-definitions drs-frame "(check-expect 1 1)")
+   (do-execute drs-frame)
+   (let ([output (fetch-output drs-frame)])
+     (cond
+       [(equal? output "The test passed!")
+        (try-interaction-tests)]
+       [else
+        (fprintf (current-error-port)
+                 "teaching-lang-sharing-modules.rkt: got bad output from execute: ~s"
+                 output)]))))
+
+(define (try-interaction-test drs-frame)
+  (type-in-interactions drs-frame "1\n")
+  (wait-for-computation drs-frame)
+  (let ([interactions-output (fetch-output drs-frame)])
+    (unless (equal? interactions-output "The test passed!\n> 1\n3")
+      (error 'teaching-language-sharing-modules.rkt
+             "got bad output from interaction: ~s\n" 
+             interactions-output))))