Re: Add completion to compilation-read-command

[Philip Kaludercic <philipk@posteo.net>]

Spyros Roum <spyros.roum@posteo.net> writes:

> Philip Kaludercic wrote:
>>>>>                                                                  , I was
>>>>> missing auto-complete a lot.
>>>>> I managed to add this functionality by writing a simple function based
>>>>> on compilation-read-command that uses completing-read instead of
>>>>> read-shell-command.
>>>> Do you know about the `bash-completion' package?  It enhances
>>>> `read-shell-command' completion with completion data provided by bash.
>>>> It is very easy to set up,
>>>>
>>>>     (use-package bash-completion :ensure t
>>>>       :init (bash-completion-setup))
>>>>
>>>> should do it.
>>> I was not aware of this, but it doesn't seem to do what I'm looking for.
>>> For once, I am not using bash, but even ignoring that it doesn't seem
>>> to have the effect I'm looking for.
>>>
>>> I'm trying to get the compile prompt to suggest completion based on
>>> past commands I've run.
>> My bad.  In that case, why not use C-r to search `compile-history'?
>
> I'm not sure if you are suggesting that I should be able to use C-r in
> the compile prompt, if so there might be a keybind issue as I'm using
> evil and C-r does not do that for me.
> If that's the case, could you name the function that does that? It
> could be what I'm looking for.

Oh, sorry about that.  C-r is just the regular `isearch-backward'
binding.

>>>>> Then I used advice-add to overwrite the
>>>>> original compilation-read-command with mine.
>>>>>
>>>>> So far this works well, and as far as I can tell there is no good
>>>>> reason not to make compile auto-completing, it already has a history
>>>>> that you can navigate anyway.
>>>>>
>>>>> With that said, this is the first time I write here and the first time
>>>>> I'm trying to contribute to emacs, so I'm not sure what the best way
>>>>> to go from here would be.
>>>>> I think some decisions would need to be taken, for once I am not sure
>>>>> if it's acceptable to change the default and make it completing or if
>>>>> there should be an option for it.
>>>> I am not sure if you meant to attach any code, but that would probably
>>>> be the best place to start.
>>>>
>>>>> Looking forward to your feedback, thanks
>>> You are right I should have posted code, so here is what I have:
>>>
>>>    (defun compilation-read-command-with-autocomplete (command)
>>>      "Use `completing-read` to add autocomplete powers to compilation read"
>>>      (completing-read "Compile command: " compile-history
>>>        nil nil command
>>>        (if (equal (car compile-history) command)
>>>          '(compile-history . 1)
>>>          'compile-history)))
>>>
>>>    (advice-add
>>>      #'compilation-read-command
>>>      :override #'compilation-read-command-with-autocomplete)
>> If this were added to Emacs, we probably wouldn't use advice.  I think
>> the best strategy for you would be to prepare a patch against compile.el
>> and add a user option that allows prompting the user with
>> completing-read.  What do you think?
>
> I agree advice is not a good solution if this gets merged, this is
> just what I have in my config to make it work.
>
> I believe an option defaulting to the current behavior is fine,
> assuming we don't want to just change it to the completing version all
> together.

I think that would be to invasive.

> However, I am somewhat lost on what that option might look
> like. Probably some customizable option based on which
> compilation-read-command's internals change to either the current or
> my version?

The easiest choice is just a user option that holds function, presumably
without taking any argument The default value would use regular
shell-read-command, and a suggested alternative could be your
suggestion.

> If so, I will need to figure out how the customizable system works
> internally in order to use it. Any pointers on that would be
> appreciated.

It will probably look something like this

        (defcustom compilation-prompt-function 
          #'complation-prompt-using-read-shell-command
          "[document the user option here]."
          :version "31.0"
          :type 'function)