Disable minor mode when in another minor mode

Question

I'm running a distribution of spacemacs and am currently working in clojure's cider debugger, and an issue I've run into is that several of the cider--debug-mode keybindings are shadowed by evil-mode. I've tried a few things with my configuration so far, including adding a hook on the cider--debug-mode which defines a keybinding to allow me to use the keys for their intended purpose again, which didn't work, and I've also simply called (evil-mode) in the lambda as well since just calling the function with no args will toggle the mode. However I've continued to experience the shadowed keybinds regardless. When I manually disable evil-mode before beginning debugging it works as intended, so it seems to me almost as if the hook isn't running properly.

Why might that be?

Answer 1

No (evil-mode) called non-interactively does not toggle. It unconditionally switches evil-mode on. You have to call (evil-mode -1) in your program to switch evil-mode off.

See the doc of define-minor-mode:

The toggle command takes one optional (prefix) argument. If called interactively with no argument it toggles the mode on or off. A positive prefix argument enables the mode, any other prefix argument disables it. From Lisp, an argument of toggle toggles the mode, whereas an omitted or nil argument enables the mode. This makes it easy to enable the minor mode in a major mode hook, for example. If doc is nil, the macro supplies a default documentation string explaining the above.

Answer 2

Here's an actual solution to the problem you've encountered:

(defun my-cider-debug-setup ()
  (evil-make-overriding-map cider--debug-mode-map 'normal)
  (evil-normalize-keymaps))

(add-hook 'cider--debug-mode-hook 'my-cider-debug-setup)

It will make debug keys work with CIDER while not disabling Evil.