Create a parseable time tracking log for vim. Requires https://gist.github.com/joequery/6231493 for the `git info` command.

gistfile1.txt

" Lets me know how much time I've spent editing a file
" Keyboard shortcut -> \dt
augroup TimeSpentEditing
au!
au BufWinEnter * if !exists('b:tstart')|let b:tstart=reltime()|en
augroup END

function! TimeSpentEditing()
  let secs = str2nr(reltimestr(reltime(b:tstart)))
  let hours = secs / 3600
  let minutes = (secs - hours * 3600) / 60
  let seconds = secs - hours * 3600 - minutes * 60
  return printf("%d:%02d:%02d", hours, minutes, seconds)
endfunction

function! s:logTimespent()
  let secs = str2nr(reltimestr(reltime(b:tstart)))
  let curFile = expand("%:p")
  let time = TimeSpentEditing()
  let path = expand("$HOME/.vimtime")
  let timestamp = strftime('%s')
  let end_timestamp = str2nr(timestamp)
  let start_timestamp = end_timestamp - secs
  "execute '!echo ' . curFile . ' : ' . time . ' >> ' . path
  execute ':silent !echo ' . start_timestamp . '-' . timestamp . ':$(git info):' . curFile . ':[' . time . '] >> ' . path
endfunction

autocmd VimLeave * call s:logTimespent()

com! TimeSpentEditing echo TimeSpentEditing()
map <silent> <leader>dt :TimeSpentEditing<CR>