Ale: Change gutter color if there're signs

[sublee]

I moved to ALE from Syntastic few days ago.

ALE turns on or off the gutter while I'm typing code. It changes my editor layout frequently. I feel annoying about it. So I configured to show the gutter always. By this setting, it's difficult to detect whether there're some signs to fix or not.

I want to change gutter color to magenta when only there're some signs to detect easily:

I don't know how use Vim script but it looks possible if ale#sign#SetSigns change the color of SignColumn based on len(l:signlist):

function! ale#sign#SetSigns(buffer, loclist) abort
    let l:signlist = ale#sign#CombineSigns(a:loclist)
    if len(l:signlist) == 0
        hi SignColumn ctermbg=black
    else
        hi SignColumn ctermbg=magenta
    endif
    ...
endfunction

But I don't want to modify this function myself. Is there something right way to achieve it?

[w0rp]

Doesn't sound like it's too difficult to implement. This could be supported by the plugin if someone wants to work on it. I'll pick it up some time if no one else does.

[sublee]

@w0rp Thank you so much! It would be necessary to use ALE comfortably.

[w0rp]

I have added an option for changing the sign column color when problems are detected. See :help g:ale_change_sign_column_color.