New test case for weak hash tables (doesn't pass yet).

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 Change: 180291
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mps/example/scheme/test-weak.scm

@@ -0,0 +1,30 @@
+;;; test-weak.scm -- weak hashtable tests for the MPS toy Scheme interpreter
+
+(load "test-common.scm")
+
+;; First, check that all the hash tables behave as expected.
+
+(define (ht-test ht-fun hash-fun cmp-fun key)
+  (let* ((ht (ht-fun hash-fun cmp-fun))
+         (f (lambda (n) (equal? (hashtable-ref ht (key n) #f) n)))
+         (g (lambda (n) (hashtable-set! ht (key n) n)))
+         (r (range 25)))
+    (for-each g r)
+    (all (map f r))))
+
+(define (stringify n) (make-string n #\b))
+(check '(ht-test make-hashtable string-hash string=? stringify) #t)
+(check '(ht-test make-weak-key-hashtable string-hash string=? stringify) #t)
+(check '(ht-test make-weak-value-hashtable string-hash string=? stringify) #t)
+(check '(ht-test make-doubly-weak-hashtable string-hash string=? stringify) #t)
+(define (symbolize n) (string->symbol (make-string n #\a)))
+(check '(ht-test make-hashtable eq-hash eq? symbolize) #t)
+(define (identity n) n)
+(check '(ht-test make-hashtable eqv-hash eqv? identity) #t)
+
+
+;; The MPS doesn't actually guarantee promptness of splatting. But we
+;; have to test it somehow!
+
+(write-string "All tests pass.")
+(newline)