diff --git a/contrib/10.readline/CMakeLists.txt b/contrib/10.readline/CMakeLists.txt
index 67d78733..793b29f6 100644
--- a/contrib/10.readline/CMakeLists.txt
+++ b/contrib/10.readline/CMakeLists.txt
@@ -14,6 +14,6 @@ if (Libedit_FOUND)
   list(APPEND PICRIN_CONTRIB_INITS readline)
   list(APPEND PICRIN_CONTRIB_LIBRARIES ${Libedit_LIBRARIES})
   list(APPEND PICRIN_CONTRIB_SOURCES ${PICRIN_READLINE_SOURCES})
-  # add_custom_target(test-readline for test in ${PROJECT_SOURCE_DIR}/contrib/10.regexp/t/*.scm \; do bin/picrin "$$test" \; done DEPENDS repl)
-  # set(CONTRIB_TESTS ${CONTRIB_TESTS} test-readline)
+  add_custom_target(test-readline for test in ${PROJECT_SOURCE_DIR}/contrib/10.readline/t/*.scm \; do bin/picrin "$$test" \; done DEPENDS repl)
+  set(CONTRIB_TESTS ${CONTRIB_TESTS} test-readline)
 endif()
diff --git a/contrib/10.readline/t/test.scm b/contrib/10.readline/t/test.scm
index 68b39de4..af695621 100644
--- a/contrib/10.readline/t/test.scm
+++ b/contrib/10.readline/t/test.scm
@@ -2,14 +2,59 @@
         (scheme read)
         (scheme eval)
         (scheme write)
-        (picrin readline))
+        (picrin readline)
+        (picrin readline history)
+        (picrin test))
 
+
+;; (let loop ((n 1))
+;;   (let ((input (readline "> ")))
+;;     (if (eof-object? input)
+;;         (newline)
+;;         (begin
+;;           (add-history input)
+;;           (write (eval (read (open-input-string input)) '(picrin user)))
+;;           (newline)
+;;           (loop 1)))))
+
+;; (readline "prompt")
+  
+(define testfile "./picrin_readline_test_file")
+
+(test-begin)
+
+(test 0 (history-length))
+(add-history "0")
+(test 1 (history-length))
 (let loop ((n 1))
-  (let ((input (readline "> ")))
-    (if (eof-object? input)
-        (newline)
-        (begin
-          (add-history input)
-          (write (eval (read (open-input-string input)) '(picrin user)))
-          (newline)
-          (loop 1)))))
+  (if (> 10 n)
+      (begin
+        (add-history (number->string n))
+        (loop (+ n 1)))))
+(test 10 (history-length))
+(stifle-history 7)
+(test 7 (history-length))
+(add-history "10")
+(test 7 (history-length))
+(test #t (history-stifled?))
+(unstifle-history)
+(test #f (history-stifled?))
+(test 7 (history-length))
+(add-history "11")
+(test 8 (history-length))
+(test "10" (history-get 11))
+(remove-history 1)
+(test "10" (history-get 11))
+(test 7 (history-length))
+(write-history testfile)
+(test 7 (history-length))
+(clear-history)
+(test 0 (history-length))
+(read-history testfile)
+(test 7 (history-length))
+(clear-history)
+(truncate-file testfile 5)
+(read-history testfile)
+(test 5 (history-length))
+
+(test-end)