personal-ulc-toggle.el

(require 's)

(defun rlb3/toggle-file ()
  (interactive)
  (let* ((full-path (buffer-file-name))
         (path (rlb3/remove-ulc full-path))
         (file-type (rlb3/determine-file-type path)))
    (if (eq file-type 'test)
        (rlb3/jump-to-related-test path)
      (rlb3/jump-to-related-module path))))

(defun rlb3/remove-ulc (path)
  (let ((new-path (s-chop-prefix "/usr/local/cpanel/" path )))
    new-path))

(defun rlb3/determine-file-type (full-path)
  (cond ((s-ends-with? ".pm" full-path) 'test)
        ((s-ends-with? ".t" full-path) 'module)))

(defun rlb3/jump-to-related-module (path)
  (let ((module (rlb3/convert-to-module path)))
    (if (file-exists-p module)
        (switch-to-buffer (find-file-noselect module))
      (message "%s doesn't exist." module))))

(defun rlb3/jump-to-related-test (path)
  (let ((test (rlb3/convert-to-test path)))
    (if (file-exists-p test)
        (switch-to-buffer (find-file-noselect test))
      (message "%s doesn't exist." test))))

(defun rlb3/convert-to-module (path)
  (let ((path (concat (car (s-split "_" path)) ".pm")))
    (s-with path
      (s-replace ".t" "")
      (s-chop-prefix "t/")
      (s-prepend "/usr/local/cpanel/")
      (s-replace "-" "/"))))

(defun rlb3/convert-to-test (path)
  (s-with path
    (s-replace ".pm" ".t")
    (s-replace "/" "-")
    (s-prepend "/usr/local/cpanel/t/")))

(global-set-key (kbd "<f9>") 'rlb3/toggle-file)