add regression test against #312

t/issue/312.scm

@@ -0,0 +1,19 @@
+(import (scheme base)
+        (picrin test))
+
+(test-begin)
+(test #f (equal? (make-list 10 1) (make-list 11 1)))
+
+(let ((l1 (list 1 1))
+      (l2 (list 1 1))
+      (l3 (list 1 1 1)))
+  (set-cdr! l1 l1)
+  (set-cdr! l2 l2)
+  (set-cdr! (cdr l3) l3)
+
+  (test #f (equal? l1 (make-list 10 1)))
+  (test #t (equal? l1 l1))
+  (test #t (equal? l1 l2))
+  (test #t (equal? l1 l3)))
+
+(test-end)