Add unit tests for lib.functions.rev-map

2 files changed, 32 insertions, 2 deletions

diff --git a/lib/functions.lisp b/lib/functions.lisp
index 073e34a..4e18a0a 100644
--- a/lib/functions.lisp
+++ b/lib/functions.lisp
@@ -37,11 +37,11 @@ each member is STEP distance apart."
           (subseq lst n)))
 
 (fn rev-map (indicator lst &key (key-eq #'eq))
-    (-> (function list &key (:key-eq function)) list)
+    (-> (function sequence &key (:key-eq function)) list)
   "Given LST and INDICATOR: LST -> A, return an association list A -> 2^LST
 where key x in A has associations {y in LST : INDICATOR(y) = x}."
   (loop :with assoc-list := nil
-        :for element :in lst
+        :for element :in (coerce lst 'list)
         :for key := (funcall indicator element)
         :if (assoc key assoc-list :test key-eq)
           :do (->> (alist-val key assoc-list)
diff --git a/tests/functions.lisp b/tests/functions.lisp
index bfb7277..b629c1f 100644
--- a/tests/functions.lisp
+++ b/tests/functions.lisp
@@ -63,3 +63,33 @@
   (is-values (split 5 "Hello World")
     (string= "Hello")
     (string= " World")))
+
+(define-test (function-test rev-map)
+  :depends-on (range)
+  :compile-at :execute
+  (fail (rev-map nil nil))
+  (fail (rev-map "a string" "another string" :key-eq "not a function"))
+  (true (->> nil (rev-map #'identity) null))
+  (let ((res (rev-map #'evenp (range 1 7))))
+    (false (null res))
+    (is equal 2 (length res))
+    (is equal 3 (->> (assoc t res) cdr length))
+    (is equal 3 (->> (assoc nil res) cdr length))
+    (true (->> (assoc t res) cdr (every #'evenp)))
+    (true (->> (assoc nil res) cdr (every #'oddp))))
+  (let* ((mod* (lambda (n) (mod n 3)))
+         (res (rev-map mod* (range 1 12))))
+    (false (null res))
+    (is equal 3 (length res))
+    (is equal 3 (->> (assoc 0 res) cdr length))
+    (is equal 4 (->> (assoc 1 res) cdr length))
+    (is equal 4 (->> (assoc 2 res) cdr length))
+    (true (->> (assoc 0 res) cdr (every (lambda (x) (= (mod x 3) 0)))))
+    (true (->> (assoc 1 res) cdr (every (lambda (x) (= (mod x 3) 1)))))
+    (true (->> (assoc 2 res) cdr (every (lambda (x) (= (mod x 3) 2))))))
+  (let ((res (rev-map #'identity "lots of letters")))
+    (false (null res))
+    (is equal 2 (->> (assoc #\l res) cdr length))
+    (is equal 3 (->> (assoc #\t res) cdr length))
+    (is equal 2 (->> (assoc #\space res) cdr length))
+    (is equal 2 (->> (assoc #\s res) cdr length))))