Why is ivy-switch-buffer not found in counsel-M-x, but works when called by C-x b (or from the scratch buffer)

Question

According to helpful-key, C-x b is bound to ivy switch buffer:

According to the code, that is an interactive function. However, when I look for it in the Counsel-M-x menu, it's not found:

I figured since this is an interactive function, I should be able to call it from the M-x menu. I'm able to call it from the scratch buffer using eval-last-sexp, and through C-x b, but not M-x. Why wouldn't this show up in the M-x menu?

Answer 1

I figured since this is an interactive function, I should be able to call it from the M-x menu.

You can call it from M-x (execute-extended-command), just not from M-x (counsel-M-x). IOW, you have probably enabled counsel-mode which remaps M-x to counsel-M-x.

Quoth Counsel's Changelog file:

counsel-M-x

Some commands are intended to be called only via their key binding. Make them disappear from counsel-M-x like this:

(put 'counsel-find-symbol 'no-counsel-M-x t)

See #2270.

And indeed, by inspection, we see that:

(function-get #'ivy-switch-buffer 'no-counsel-M-x) ; => t

So if you want ivy-switch-buffer (or any similar command) to show up as a candidate in counsel-M-x completion, you can say something like the following:

(function-put #'ivy-switch-buffer 'no-counsel-M-x nil)

See also Why ivy-immediate-done is not shown in counsel-M-x.