diff --git a/contrib/10.readline/t/test.scm b/contrib/10.readline/t/test.scm
index 0487f8bf..37c8d9bb 100644
--- a/contrib/10.readline/t/test.scm
+++ b/contrib/10.readline/t/test.scm
@@ -23,34 +23,303 @@
 (test-begin)
 
 (test 0 (history-length))
+(test 0 (where-history))
 (add-history "1")
 (test 1 (history-length))
+(test 1 (where-history))
 (let loop ((n 2))
   (if (>= 10 n)
       (begin
         (add-history (number->string n))
         (loop (+ n 1)))))
+#|
+index     0   1   2   3   4   5   6   7   8   9
+history  "1" "2" "3" "4" "5" "6" "7" "8" "9" "10"
+offset    1   2   3   4   5   6   7   8   9   10
+pos       10  9   8   7   6   5   4   3   2   1
+                                              p
+|#
 (test 10 (history-length))
+(test 1 (where-history))
 (stifle-history 7)
+#|
+index     0   1   2   3   4   5   6   7   8   9
+history  "1" "2" "3"|"4" "5" "6" "7" "8" "9" "10"
+offset    1   2   3   4   5   6   7   8   9   10
+pos       10  9   8   7   6   5   4   3   2   1
+                                              p
+|#
 (test 10 (history-length))
+(test 1 (where-history))
+(test 0 (history-set-pos 0))
+#|
+index     0   1   2   3   4   5   6   7   8   9
+history  "1" "2" "3"|"4" "5" "6" "7" "8" "9" "10"
+offset    1   2   3   4   5   6   7   8   9   10
+pos       10  9   8   7   6   5   4   3   2   1
+          p
+|#
+(test 10 (where-history))
 (add-history "11")
+#|
+index     0   1   2   3   4   5    6
+history  "5" "6" "7" "8" "9" "10" "11"
+offset    5   6   7   8   9   10   11
+pos       7   6   5   4   3   2    1
+                                   p
+|#
 (test 7 (history-length))
+(test 1 (where-history))
 (test #t (history-stifled?))
 (unstifle-history)
 (test #f (history-stifled?))
 (test 7 (history-length))
+(test 1 (where-history))
 (add-history "12")
+#|
+index     0   1   2   3   4   5    6    7
+history  "5" "6" "7" "8" "9" "10" "11" "12"
+offset    5   6   7   8   9   10   11   12
+pos       8   7   6   5   4   3    2    1
+                                        p
+|#
 (test 8 (history-length))
+(test 1 (where-history))
+(test "12" (current-history))
+(test 1 (where-history))
+(test #f (previous-history))
+#|
+index     0   1   2   3   4   5    6    7
+history  "5" "6" "7" "8" "9" "10" "11" "12"
+index     5   6   7   8   9   10   11   12
+pos       8   7   6   5   4   3    2    1
+                                        p
+|#
+(test 1 (where-history))
+(test "11" (next-history))
+#|
+index     0   1   2   3   4   5    6    7
+history  "5" "6" "7" "8" "9" "10" "11" "12"
+offset    5   6   7   8   9   10   11   12
+pos       8   7   6   5   4   3    2    1
+                                   p
+|#
+(test 2 (where-history))
+(test 0 (history-set-pos 5))
+#|
+index     0   1   2   3   4   5    6    7
+history  "5" "6" "7" "8" "9" "10" "11" "12"
+offset    5   6   7   8   9   10   11   12
+pos       8   7   6   5   4   3    2    1
+                              p
+|#
+(test 3 (where-history))
+(test -1 (history-set-pos (history-length)))
+(test 3 (where-history))
+(test -1 (history-set-pos -1))
+(test 3 (where-history))
+(test 0 (history-set-pos 0))
+#|
+index     0   1   2   3   4   5    6    7
+history  "5" "6" "7" "8" "9" "10" "11" "12"
+offset    5   6   7   8   9   10   11   12
+pos       8   7   6   5   4   3    2    1
+          p
+|#
+(test (history-length) (where-history))
+(test 0 (history-set-pos (- (history-length) 2)))
+#|
+index     0   1   2   3   4   5    6    7
+history  "5" "6" "7" "8" "9" "10" "11" "12"
+offset    5   6   7   8   9   10   11   12
+pos       8   7   6   5   4   3    2    1
+                                   p
+|#
+(test 2 (where-history))
+(test "11" (current-history))
+(test 2 (where-history))
+(test "12" (previous-history))
+#|
+index     0   1   2   3   4   5    6    7
+history  "5" "6" "7" "8" "9" "10" "11" "12"
+offset    5   6   7   8   9   10   11   12
+pos       8   7   6   5   4   3    2    1
+                                        p
+|#
+(test 1 (where-history))
+(test "11" (next-history))
+#|
+index     0   1   2   3   4   5    6    7
+history  "5" "6" "7" "8" "9" "10" "11" "12"
+offset    5   6   7   8   9   10   11   12
+pos       8   7   6   5   4   3    2    1
+                                        p
+|#
+(test 2 (where-history))
 (test "11" (history-get 11))
-(remove-history 1)
-(test "11" (history-get 11))
+(test "6" (remove-history 1))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+              p
+|#
+(test 6 (where-history))
+(test "7" (current-history))
+(test "5" (next-history))
+(test #f (history-get 6))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+          p
+|#
 (test 7 (history-length))
+(history-set-pos 6)
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+                                    p
+|#
+(test 0 (history-search "7" -1))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+              p
+|#
+(test 6 (where-history))
+(history-set-pos 6)
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+                                    p
+|#
+(test -1 (history-search "7" 0))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+                                    p
+|#
+(history-set-pos 0)
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+          p
+|#
+(test -1 (history-search "7" -1))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+          p
+|#
+(test 7 (where-history))
+(history-set-pos 0)
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+          p
+|#
+(test 0 (history-search "7" 0))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+              p
+|#
+(test 6 (where-history))
+(test 0 (history-search-prefix "1" 0))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+                          p
+|#
+(test 3 (where-history))
+(history-set-pos 5)
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+                               p
+|#
+(test 0 (history-search-prefix "1" -1))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+                               p
+|#
+(test 2 (where-history))
+(test 0 (history-search-prefix "1" 0))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+                               p
+|#
+(test 2 (where-history))
+(test 0 (history-search-prefix "9" -1))
+#|
+index     0   1   2   3   4    5    6 
+history  "5" "7" "8" "9" "10" "11" "12"
+offset    5   7   8   9   10   11   12
+pos       7   6   5   4   3    2    1
+                      p
+|#
+(test 4 (where-history))
 (write-history testfile)
 (test 7 (history-length))
 (clear-history)
+#|
+index     
+history  
+offset   
+pos       
+             p
+|#
 (test 0 (history-length))
+(test 0 (where-history))
+(add-history "f")
+#|
+index      1
+history   "f"
+offset     1
+pos        1
+           p
+|#
+(test 1 (history-length))
+(test 1 (where-history))
+(test "f" (history-get 1))
 ;(read-history testfile)
-(test 7 (history-length))
+;#|
+;index     0   1   2   3   4    5    6    7
+;history  "f" "5" "7" "8" "9" "10" "11" "12"
+;offset    1   2   3   4   5    6    7   8
+;pos       8   7   6   5   4    3    2   1
+;                                        p
+;|#
+(test 8 (history-length))
 (clear-history)
 (truncate-file testfile 5)
 ;(read-history testfile)