How to tell Vim to auto-indent before saving

Question

I have recently started using Vim for my graduate level projects. The main problem I face is that sometimes I check in unindented code. I feel if I can somehow create a shortcut of auto-indent+save+close then that should solve my problem.

My .vimrc file:

set expandtab
set tabstop=2
set shiftwidth=2
set softtabstop=2
set pastetoggle=<F2>
syntax on
filetype indent plugin on

Is there any way to create such command shortcuts & override with :x (save+exit).

Please let me know.

Answer 1

Add the following to your .vimrc:

" Restore cursor position, window position, and last search after running a
" command.
function! Preserve(command)
  " Save the last search.
  let search = @/

  " Save the current cursor position.
  let cursor_position = getpos('.')

  " Save the current window position.
  normal! H
  let window_position = getpos('.')
  call setpos('.', cursor_position)

  " Execute the command.
  execute a:command

  " Restore the last search.
  let @/ = search

  " Restore the previous window position.
  call setpos('.', window_position)
  normal! zt

  " Restore the previous cursor position.
  call setpos('.', cursor_position)
endfunction

" Re-indent the whole buffer.
function! Indent()
  call Preserve('normal gg=G')
endfunction

If you want all file types to be auto-indented on save, which I strongly recommend against, add this hook to your .vimrc:

" Indent on save hook
autocmd BufWritePre <buffer> call Indent()

If you want only certain file types to be auto-indented on save, which I recommend, then follow the instructions. Lets say you want C++ files to be auto-indented on save, then create ~/.vim/after/ftplugin/cpp.vim and put this hook there:

" Indent on save hook
autocmd BufWritePre <buffer> call Indent()

The same would go for any other file types, i.e. ~/.vim/after/ftplugin/java.vim for Java and so on.