oh-my-bash/tools/upgrade.sh

#!/usr/bin/env bash

function _omb_upgrade {
  # Use colors, but only if connected to a terminal, and that terminal
  # supports them.
  local ncolors=
  if type -P tput &>/dev/null; then
    ncolors=$(tput colors)
  fi

  local RED GREEN BLUE BOLD NORMAL
  if [[ -t 1 && $ncolors && $ncolors -ge 8 ]]; then
    RED=$(tput setaf 1 2>/dev/null || tput AF 1 2>/dev/null)
    GREEN=$(tput setaf 2 2>/dev/null || tput AF 2 2>/dev/null)
    BLUE=$(tput setaf 4 2>/dev/null || tput AF 4 2>/dev/null)
    BOLD=$(tput bold 2>/dev/null || tput md 2>/dev/null)
    NORMAL=$(tput sgr0 2>/dev/null || tput me 2>/dev/null)
  else
	  RED=""
	  GREEN=""
	  BLUE=""
	  BOLD=""
	  NORMAL=""
  fi

  printf '%s\n' "${BLUE}Updating Oh My Bash${NORMAL}"

  # Note: The git option "-C PATH" is only supported from git-1.8.5
  # (https://github.com/git/git/commit/44e1e4d6 2013-09).  On the other hand,
  # the synonym "--git-dir=PATH/.git --work-tree=PATH" is supported from
  # git-1.5.3 (https://github.com/git/git/commit/892c41b9 2007-06).
  if ! command git --git-dir="$OSH/.git" --work-tree="$OSH" pull --rebase --stat origin master; then
    # In case it enters the rebasing mode
    printf '%s\n' "oh-my-bash: running 'git rebase --abort'..."
    command git --git-dir="$OSH/.git" --work-tree="$OSH" rebase --abort
    printf "${RED}%s${NORMAL}\n" \
           'There was an error updating.' \
           "If you have uncommited changes in '$BOLD$OSH$NORMAL$RED', please commit, stash or discard them and retry updating." \
           "If you have your own local commits in '$BOLD$OSH$NORMAL$RED' that conflict with the upstream changes, please resolve conflicts and merge the upstream manually."
    return 1
  fi

  printf '%s' "$GREEN"
  # shellcheck disable=SC1003,SC2016
  printf '%s\n' \
    '         __                          __               __  ' \
    '  ____  / /_     ____ ___  __  __   / /_  ____ ______/ /_ ' \
    ' / __ \/ __ \   / __ `__ \/ / / /  / __ \/ __ `/ ___/ __ \' \
    '/ /_/ / / / /  / / / / / / /_/ /  / /_/ / /_/ (__  ) / / /' \
    '\____/_/ /_/  /_/ /_/ /_/\__, /  /_.___/\__,_/____/_/ /_/ ' \
    '                        /____/                            '
  printf "${BLUE}%s\n" "Hooray! Oh My Bash has been updated and/or is at the current version."
  printf "${BLUE}${BOLD}%s${NORMAL}\n" "To keep up on the latest news and updates, follow us on GitHub: https://github.com/ohmybash/oh-my-bash"
  if [[ $- == *i* ]]; then
    declare -f _omb_util_unload &>/dev/null && _omb_util_unload
    # shellcheck disable=SC1090
    source ~/.bashrc
  fi
}
_omb_upgrade