How to show quickfix without jumping to quickfix window?

Question

I'm writing small liniting plugin and I want to show errors in the quickfix as soon as errorfile changes.

fu! OpenErrors(job_id, data, event)
    let l:winid = win_getid()
    let l:output = split(a:data[0])
    echom l:output[0] . l:output[2]
    let l:view = winsaveview()
    exe 'silent! cfile! ' . escape(l:output[0] . l:output[2], '%#/')
    call winrestview(l:view)
    if len(getqflist()) > 0
        copen
    else
        cclose
    endif
    call win_gotoid(l:winid)
endfu

The problems with this code is that it the cursor jumps to quickfix window and it's annoying when errorfile changes fast.

Answer 1

In Build-Tools-Wrapper, the callback receives the new line to display (as the job simply executes make (or equivalent) and doesn't play with any intermediary file), the line is processed with :caddexpr. If I'm supposed to be at the bottom I simply execute :cbottom -- moving the cursor (in the qf windows) changes that. These two commands don't change the current window I'm in.

Also when I start the compilation, I open the quickfix window without jumping to it. Actually, I jump to it in order to apply a few hooks (like syntax highlighting, concealment...) and eventually I jump back to the window I was in before starting the background compilation. Along the way I've an old trick able to detect if we need a qf window in other situations.

Answer 2

Try this quickfix preview plugin: https://github.com/ronakg/quickr-preview.vim

Answer 3

Here is what I ended up using to prevent the cursor from moving after executing copen:

function! OpenErrors(job_id, data, event)
    " Store the original window number
    let l:winnr = winnr()

    " Open a window to show the current list of errors

    " If focus changed, jump to the last window
    if l:winnr !=# winnr()
        wincmd p
    endif
endfunction

Also, the vim-qf plugin makes it easier to work with the location/quickfix list.

Answer 4

cwindow does your open/close behaviour but jumps to the quickfix if opening.

wincmd p jumps to the previous window (and should maintain the cursor position).

A simple method:

cclose | copen | wincmd p | cwindow

A modification of your code that probably works (untested):

fu! OpenErrors(job_id, data, event)
    let l:was_in_qf = &buftype == 'quickfix'
    let l:output = split(a:data[0])
    echom l:output[0] . l:output[2]
    exe 'silent! cgetfile! ' . escape(l:output[0] . l:output[2], '%#/')
    cwindow
    if !l:was_in_qf && &ft == 'qf'
        wincmd p
    endif
endfu