Advising interactive commands

Advising interactive commands

[Ag Ibragimov]

Can someone please clarify my confusion about advising interactive commands? For some reason, I am unable to advise commands with interactive parameters. So, check this out:

(defun my-command (file)
  (interactive (list (read-file-name "Find file: "))))

When called, it prompts to select a file, alright?

Now, if I do this:

(defun my-command-override ()
  (message "running override"))

(advice-add 'my-command :override 'my-command-override)

I expect my new function to run instead, right? And indeed, this works:

(funcall 'my-command) ;; immediately shows the message

However, for whatever reason the following doesn't:

(call-interactively 'my-command)

Meaning, that it doesn't fully override it when called from M-x menu. I mean, it would prompt for the file but only after that it would call my-command-override. Why is that? Is this expected? If it is, how do you advise such commands so they don't show prompts for their parameters?

Re: Advising interactive commands

[Andreas Schwab]

This paragraph in the doc string of add-function applies here:

If one of FUNCTION or OLDFUN is interactive, then the resulting function
is also interactive.  There are 3 cases:
- FUNCTION is not interactive: the interactive spec of OLDFUN is used.

-- 
Andreas Schwab, schwab@linux-m68k.org
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