@@ -49,7 +49,8 @@

 ;; TODO: implement test

 (defun %split-on-char (divider string &key count (test nil))

-  (declare (optimize #+dev (debug 3) (speed 3) (space 2))

+  (declare (optimize #+dev (debug 3) #+dev (speed 0) #+dev (space 0)

+                     #-dev (speed 3) #-dev(space 2))

            (type (or null array-length) count)

            (type (or null function symbol) test)

            (type character divider)

@@ -60,21 +61,25 @@

   (check-type string simple-string)

   (flet ((count-splits (string)

-           (declare (optimize (speed 3))

+           (declare (optimize #+dev (debug 3) #+dev (speed 0) #+dev (space 0)

+                              #-dev (speed 3) #-dev(space 2))

                     (type simple-string string))

-           (do* ((x (the array-length 0) (1+ x))

-                 (cur-char #1=(aref string x) #1#)

-                 (result (the array-length

-                              (if (char= cur-char divider)

-                                  1

-                                  0))

-                         (if (char= cur-char divider)

-                             (1+ result)

-                             result)))

-                ((= x (1- (length string))) (1+ result))

-             (declare (type array-length result))))

+           (if (/= 0 (length string))

+               (do* ((x (the array-length 0) (1+ x))

+                     (cur-char #1=(aref string x) #1#)

+                     (result (the array-length

+                                  (if (char= cur-char divider)

+                                      1

+                                      0))

+                             (if (char= cur-char divider)

+                                 (1+ result)

+                                 result)))

+                    ((= x (1- (length string))) (1+ result))

+                 (declare (type array-length result)))

+               0))

          (find-pos (start-pos)

-           (declare (optimize (speed 3))

+           (declare (optimize #+dev (debug 3) #+dev (speed 0) #+dev (space 0)

+                     #-dev (speed 3) #-dev(space 2))

                     (type array-index start-pos))

            (etypecase test

              (function (position divider string :start start-pos :test test))

@@ -85,7 +90,7 @@

       (setf count (count-splits string)))

     (check-type count array-length)

-    (let ((parts (make-array count :fill-pointer 0))

+    (let ((parts (make-array (max count 1) :fill-pointer 0))

           (start-pos (the fixnum 0)))

       (declare (dynamic-extent start-pos))

       (prog1 parts

@@ -97,10 +102,11 @@

              (setf start-pos (1+ end-pos))

            while (< (length parts) (1- count))

            finally

-             (when (and end-pos count)

-               (vector-push (subseq string start-pos)

-                            parts))

-             )))))

+             (cond ((and end-pos count)

+                    (vector-push (subseq string start-pos)

+                                 parts))

+                   ((not end-pos)

+                    (vector-push "" parts))))))))

 (defun %split-on-string (divider string &key count (test nil))

   (declare (optimize #+dev (debug 3) (speed 3))

@@ -1,7 +1,9 @@

 (in-package :fwoar.string-utils)

 (defun vos-equal (a b)

-  (every 'equal a b))

+  (and (= (length a)

+          (length b))

+       (every 'equal a b)))

 (progn

   (st:deftest string-split-as-expected-with-test ()

@@ -36,6 +38,10 @@

     (st:should be vos-equal

                #("a" "b" "c" "d")

                (%split-on-string " " "a b c d")))

+  (st:deftest string-split-empty-string-as-expected ()

+    (st:should be vos-equal

+               #("")

+               (%split-on-string "/" "")))

   (st:deftest char-split-as-expected-with-test ()

     (st:should be vos-equal

@@ -65,4 +71,9 @@

     (st:should be vos-equal

                #("a" "b" "c" "d")

                (%split-on-char #\space "a b c d")))

+

+  (st:deftest char-split-empty-string-as-expected ()

+    (st:should be vos-equal

+               #("")

+               (%split-on-char #\/ "")))

   )