A lighter and faster powerlevel9k git vcs segment (for windows)

powerlevel9k-nano-git.zsh-theme

prompt_nano_git() {
  CURRENT_BRANCH=$(git rev-parse --abbrev-ref HEAD 2>/dev/null)
  if [[ $CURRENT_BRANCH == "HEAD" ]]; then
    COMMIT_ID=$(git rev-parse --short HEAD 2>/dev/null)
    if [[ -n $COMMIT_ID ]]; then
      CURRENT_BRANCH="$(git rev-parse --short HEAD 2>/dev/null) (detached)"
    else
      CURRENT_BRANCH="master (empty)"
    fi
  fi
  COUNT_CHANGES=$(git status --porcelain 2>/dev/null | wc -l)
  UNTRACKED_CHANGES=$(git status --porcelain 2>/dev/null | egrep "^.\S" | wc -l)
  if [[ $COUNT_CHANGES -eq 0 ]]; then
    STATUS_COLOR="green"
  else
    STATUS_COLOR="yellow"
  fi
  if [[ $UNTRACKED_CHANGES -ne 0 ]]; then
    SUFFIX=" $(print_icon 'VCS_UNSTAGED_ICON')"
  fi
  if [[ -n $CURRENT_BRANCH ]]; then
    "$1_prompt_segment" "$0" "$2" "$STATUS_COLOR" "$DEFAULT_COLOR" "$CURRENT_BRANCH$SUFFIX" 'VCS_BRANCH_ICON'
  fi
}

vcs segment is slow on windows, this implementation has less functionnalities and is faster.