Question

I’m using the latest MacVim. Is there any way to have it so if I open MacVim without a file or with only one file, it sets the window width to n characters? Then if I do a vertical split it will expand the window width to 2n characters? Same for 3 vertical splits but it will stop increasing the width after the window is 3n characters. Then if I close those splits it will resize down?

Answer 1

This appears to work. Whether or not a horizontal split has been done, any time a vsplit is created or deleted the window is resized.

let g:auto_resize_width = 40
function! s:AutoResize()
    let win_width = winwidth(winnr())
    if win_width < g:auto_resize_width
        let &columns += g:auto_resize_width + 1
    elseif win_width > g:auto_resize_width
        let &columns -= g:auto_resize_width + 1
    endif
    wincmd =
endfunction

augroup AutoResize
    autocmd!
    autocmd WinEnter * call <sid>AutoResize()
augroup END

Configure the window width by changing the variable at the top. You probably want to do something like let g:auto_resize_width = &columns to set it to use the width of the original window as the width to resize by.

Things get a little wonky if you have so many vsplits that the window becomes maximized horizontally. I’m trying to find a fix and I’ll post it if I find one.