How do you exit vimdiff mode in vim, specifically, for Fugitive?

Question

I am using vim with the fugitive extension. It has a :Gdiff command which brings you into vimdiff mode, but what is the right/quick way to close/quit vimdiff mode?

I.e.,

Answer 1

This works fine for me, combining some of the existing ideas here:

function! MyCloseDiff()
  if (&diff == 0 || getbufvar('#', '&diff') == 0)
        \ && (bufname('%') !~ '^fugitive:' && bufname('#') !~ '^fugitive:')
    echom "Not in diff view."
    return
  endif

  " close current buffer if alternate is not fugitive but current one is
  if bufname('#') !~ '^fugitive:' && bufname('%') =~ '^fugitive:'
    if bufwinnr("#") == -1
      b #
      bd #
    else
      bd
    endif
  else
    bd #
  endif
endfunction
nnoremap gD :call MyCloseDiff()