Autocomplete compile comands based on compile-history

[SpyrosRoum]

Hello, first of all I'm not sure if vertico is the correct place to ask, but if anyone I'm sure you would know how to direct me.

What I want to do is to get auto-complete in the compile-command prompt that will auto-suggest entries from compile-history. My searches have been failing me, but I believe this has to be possible somehow.
compile-history already has a list with values, pressing the up/down arrows even navigates this list by default, I'm just not sure how to hook it up to the vertico ui.

Any help would be greatly appreciated, thank you in advance

[SpyrosRoum]

To my absolute surprise I was able to do this myself after reading through vertico's readme and the linked emacs docs for completions.. I'll leave my solution here since I don't want this to be another "nvm I fixed it" post, and I'll leave the issue open in case you know of any better solutions, but feel free to just close.

;; compilation-read-command uses `read-shell-command` by default, which doesn't use
;; completion at all. So I overwrite it to use `completing-read` instead, which seems to work great.
(defun compilation-read-command (command)
  (completing-read "Compile command: " compile-history
    nil nil command
    (if (equal (car compile-history) command)
      '(compile-history . 1)
      'compile-history)))

[minad]

I converted to a Q&A discussion for others to see the solution.

[rudolf-adamkovic]

@SpyrosRoum

This is fun! Thank you for sharing.

Here is a version that shows all candidates, like say M-x:

(defun compilation-read-command (command)
  (completing-read "Compile command: " compile-history
                   nil nil nil
                   (if (equal (car compile-history) command)
                       '(compile-history . 1)
                     'compile-history)
                   command))

[rudolf-adamkovic]

Note. It would perhaps be a good idea to contribute a patch to Emacs where the user could set the compilation-read-command to a function like the ones above (to avoid risky overrides).

[SpyrosRoum]

Note. It would perhaps be a good idea to contribute a patch to Emacs where the user could set the compilation-read-command to a function like the ones above (to avoid risky overrides).

Hey, I wouldn't mind doing that but I'm relatively new to elisp so I'm not sure how that would look like. Do you have of any other mechanisms that work like that currently that I can check out?

[rudolf-adamkovic]

I think the best next step would be to bring this (IMO, great) idea up for discussion over on the emacs-devel mailing list.

[rudolf-adamkovic]

And here is an advice, so that Help shows

This function has :override advice: ‘my-compilation-read-command’.

(defun my-compilation-read-command (command)
  (completing-read "Compile command: " compile-history
                   nil nil nil
                   (if (equal (car compile-history) command)
                       '(compile-history . 1)
                     'compile-history)
                   command))

(advice-add #'compilation-read-command
            :override
            #'my-compilation-read-command)