bug#66998: 29.1; Regression for recursive keyboard macros + minibuffers in (I think) Emacs 28

[Eli Zaretskii]

> From: Morgon Kanter <morgon.kanter@gmail.com>
> Date: Tue, 7 Nov 2023 22:29:22 -0500
> 
> I believe there is a regression, but possibly intentional, caused by this 
> patch:
> https://github.com/emacs-mirror/emacs/commit/203e61ff837128b397eb313a5bb1b703f0eae0ec
> 
> This affects minibuffers created when (kbd-macro-query t) is called as
> part of the hook that runs when the (read-from-minibuffer) function is
> called. You get the error message "Not in most nested command loop". For
> example, this code here:
> https://www.emacswiki.org/emacs/KeyboardMacros#h5o-5
> 
> Or, pasting the code in question:
> 
>     (defun my-macro-query (arg)
>       "Prompt for input using minibuffer during kbd macro execution.
>     With prefix argument, allows you to select what prompt string to use.
>     If the input is non-empty, it is inserted at point."
>       (interactive "P")
>       (let* ((prompt (if arg (read-from-minibuffer "PROMPT: ") "Input: "))
>              (input (minibuffer-with-setup-hook (lambda () (kbd-macro-query 
> t))
>                       (read-from-minibuffer prompt))))
>         (unless (string= "" input) (insert input))))
>     (global-set-key (kbd "C-x Q") 'my-macro-query)
> 
> If you attempt to start a keyboard macro via F3, then attempt to read a
> minibuffer with the above code via C-x Q, upon pressing ENTER to close
> the minibuffer, you get the following error message:
> "Not in most nested command loop"
> 
> You won't be able to close out the minibuffer, the only way I found to
> proceed was to C-] or multiple escapes, which canceled the keyboard
> macro creation. As a result, it appears we can't use the above method to
> read and set variables during keyboard macro creation. I'm not sure if
> this is intentional or not, or if there's a replacement for the above or
> not. But it appears to be a regression from before that series of patches.

Alan, can you please look into this?