A snippet of bash to download the latest version of the git completion files locally and keep track of what version they are on

gistfile1.sh

update_git_completion () {
  # try to download the "correct" version of git completion
  git_version=`git --version | cut -d" " -f3`

  # check if we have the right version of git completion stuffs
  if [[ -f git-completion.bash && -f git_completion_version && $git_version == `cat git_completion_version` ]]
  then
    echo "Up to date for $git_version"
  else
    # save the git version number
    rm git_completion_version &>/dev/null
    echo $git_version > git_completion_version
    
    echo "Downloading git completion script for $git_version"
    # here we fail (-f) quietly and save to same name as remote (-O)
    curl -f -O https://raw.github.com/git/git/v$git_version/contrib/completion/git-completion.bash
    curl -f -O https://raw.github.com/git/git/v$git_version/contrib/completion/git-prompt.sh
  fi
}