BUG: which-key not showing

[bmag]

With vanilla emacs, which-key does not show at all. Works fine with spacemacs, though.

Steps to reproduce:

1. emacs -Q -l path/to/s.el -l path/to/which-key.el
2. M-x which-key-mode
3. C-x
   Expected result: which-key shown in the minibuffer
   Actual result: which-key isn't shown at all

Probably introduced by some recent change.
Tried emacs 24.3, 24.5 and 25, same behavior. On spacemacs I don't experience this bug - which-key works as expected.

[justbur]

Can you try it now?

I check directly for the key-binding pointing to a keymap now. In vanilla emacs, this-single-command-keys returns a symbol so the bug was in the logic for the update function

[bmag]

Works!