Redirect the output of a Vim or external command into a scratch buffer

redir.md

Redirect the output of a Vim or external command into a scratch buffer

Usage (any shell)

Show the full output of command :hi in a scratch buffer:

:Redir hi

Show the full output of command :!ls -al in a scratch buffer:

:Redir !ls -al

Show the full output of the previous command in a scratch buffer:

:Redir!

Additional usage (depends on non-standard shell features so YMMV)

Evaluate the current line with node and show the full output in a scratch buffer:

" current line
console.log(Math.random());

" Ex command
:.Redir !node

" scratch window
0.03987581000754448

Evaluate the current buffer + positional parameters with bash and show the full output in a scratch buffer:

" content of buffer
echo ${1}
echo ${2}

" Ex command
:%Redir !bash -s foo bar

" scratch window
foo
bar

---

My Vim-related gists.

redir.vim

function! Redir(cmd = '', rng = 0, start = 1, end = 1, bang = '')
    let cmd = a:cmd->trim()
    for win in range(1, winnr('$'))
        if getwinvar(win, 'scratch')
            execute win . 'windo close'
        endif
    endfor
    if a:bang == '!' && cmd->empty()
        let cmd = expand(@:)->trim()
    endif
    if cmd =~ '^!'
        let ext_cmd = cmd =~' %'
                \ ? matchstr(substitute(cmd, ' %', ' ' . shellescape(escape(expand('%:p'), '\')), ''), '^!\zs.*')
                \ : matchstr(cmd, '^!\zs.*')
        if a:rng == 0
            let output = systemlist(ext_cmd)
        else
            let joined_lines = join(getline(a:start, a:end), '\n')
            let cleaned_lines = substitute(shellescape(joined_lines), "'\\\\''", "\\\\'", 'g')
            let output = systemlist(ext_cmd . " <<< $" . cleaned_lines)
        endif
    else
        redir => output
        execute cmd
        redir END
        let output = split(output, "\n")
    endif
    vnew
    let w:scratch = 1
    setlocal buftype=nofile bufhidden=wipe nobuflisted noswapfile
    call setline(1, output)
endfunction


" This command definition includes -bar, so that it is possible to "chain" Vim commands.
" Side effect: double quotes can't be used in external commands
command! -nargs=? -complete=command -bar -range -bang Redir silent call Redir(<q-args>, <range>, <line1>, <line2>, '<bang>')

" This command definition doesn't include -bar, so that it is possible to use double quotes in external commands.
" Side effect: Vim commands can't be "chained".
command! -nargs=? -complete=command -range -bang Redir silent call Redir(<q-args>, <range>, <line1>, <line2>, '<bang>')

guys can you give me something in luascript?!

Thanks romainl for amazing work! I implement this command with lua script, with some extra commands to get repl-like features.

Also, this lua implementations support vertical and horizontal modifiers.

And note that this lua script doesn't use sh -c to do things, it spawns process directly, so no shell commands available but also no shell escaping needed.

My implementation in lua

Thanks, @Leenuus.

@gachikuku it looks like your wish came true.

Thank you @Leenuus! 🤗
@romainl it did.

Thank you @Leenuus! 🤗 @romainl it did.

Thanks, @Leenuus.

@gachikuku it looks like your wish came true.

Hi, @gachikuku , I rewrite my ugly codes and write a README like @romainl did.

And with vim.uv power, this implementation is totally async.

Split direction and stderr are handled too.

Can't thank @romainl more for such a simple, elegant, and powerful solution.

My gist here

You are very welcome, @Leenuus. Your gist seems almost plugin-ready.

You are very welcome, @Leenuus. Your gist seems almost plugin-ready.

Hope that I don't overengineer. 😂

@Leenuus @romainl is right!
That thing reserves a repo not a gist.
Plus it would be easier for folks to set it up, so make it a plugin.

@romainl Would you be open to turning this gist into a plugin? I would do it (even just for my own convenience), but not being the author, I couldn't properly license it.

any idea how to do this when you're already in the 'hit-enter' / 'more-prompt'

@MicahMartin The output of the previous command is not accessible so we have to re-run it. I have added that feature: at the "hit enter" or "more" prompt, do :Redir!.

FWIW, I already refactored this into a plugin some time ago. I finally published it here.

awesome!