rename all files in a dir to lowercase or uppercase (name only / extension only / full name)

bull-file-name-upper-lower.clj

(local mfs (require "minifs"))
(local str (require "std.string"))

(if (not (= 3 (# arg)))
  (do (print "not valid input arguments")
    (os.exit)))

(if (not (or (= (. arg 1) "-l") (= (. arg 1) "-u")))
  (do (print "first arg must be a function [-l or -u]")
    (os.exit)))

(local func (if (= (. arg 1) "-l") "lower" "upper"))

(if (not (or (= (. arg 2) "-n") (= (. arg 2) "-x") (= (. arg 2) "-f")))
  (do (print "first arg must be a function [-l or -u]")
    (os.exit)))

(local mode (if (= (. arg 2) "-n") "name"
                (= (. arg 2) "-x") "extension"
                                   "full"))

(if (not (mfs.exists (. arg 3)))
  (do
    (print "destination path does not exist")
    (os.exit)))

(local path (. arg 3))
(local get-file-name (mfs.files path))

(fn trans [func mode file]
  (let [nme (. (str.split file "%.") 1)
        ext (. (str.split file "%.") 2)
        tfn (if (= func "lower") string.lower string.upper)]
    (if (= "full" mode) (.. (tfn nme) "." (tfn ext))
        (= "name" mode) (.. (tfn nme) "." ext)
        (= "extension" mode) (.. nme "." (tfn ext)))))

(do 
  (var file-name (get-file-name))
  (while (~= nil file-name)
    (when (not (or (= file-name ".") (= file-name "..")))        
      (mfs.move 
       (.. path "/" file-name)
       (.. path "/" (trans func mode file-name))))      
    (set file-name (get-file-name))))

the script is written in fennel script
this file has nothing to do with clojure or clojurescript.
I had to name the script as a clojure file in order to fool github to give the code a proper color scheme,

examples:

• full name uppercase: fennel app.fnl -u -f test-dir
• full name lowercase: fennel app.fnl -l -f test-dir
• name only uppercase: fennel app.fnl -u -n test-dir
• extension only lower: fennel app.fnl -l -x test-dir