Error when loading a configuration without hitting tab or rotating the search ring

[radamant]

It appears there is no default candidate for completing read.

Reproduction:

1. run emux-session-load-template
2. see default option chosen
3. hit RET
4. see following error:

Debugger entered--Lisp error: (file-error "Cannot open load file" "/Users/adam/.emacs.d/emux-templates/.el")
  load("/Users/adam/.emacs.d/emux-templates/.el" nil nil t)
  load-file("~/.emacs.d/emux-templates/.el")
  (progn (emux-session-create (list (quote :name) template)) (load-file (concat "~/.emacs.d/emux-templates/" template ".el")) (message "%s template loaded" template))
  (if (cond ((not (emux-session-from-name template)) t) (t (yes-or-no-p (format "session %s already exists, really load?" template)))) (progn (emux-session-create (list (quote :name) template)) (load-file (concat "~/.emacs.d/emux-templates/" template ".el")) (message "%s template loaded" template)))
  (let ((template (emux-completing-read "load emux session template: " (mapcar (function (lambda (filename) (substring filename 0 -3))) (directory-files "~/.emacs.d/emux-templates" nil "^[^#].*.el"))))) (if (cond ((not (emux-session-from-name template)) t) (t (yes-or-no-p (format "session %s already exists, really load?" template)))) (progn (emux-session-create (list (quote :name) template)) (load-file (concat "~/.emacs.d/emux-templates/" template ".el")) (message "%s template loaded" template))))
  emux-session-load-template()
  call-interactively(emux-session-load-template nil nil)

[radamant]

This does not reproduce if I set emacs-completing-read-command to "ido-completing-read"