gistfile1.sh

NONE="\[\033[0m\]"    # unsets color to term's fg color
K="\[\033[0;30m\]"    # black
R="\[\033[0;31m\]"    # red
G="\[\033[0;32m\]"    # green
Y="\[\033[0;33m\]"    # yellow
B="\[\033[0;34m\]"    # blue
M="\[\033[0;35m\]"    # magenta
C="\[\033[0;36m\]"    # cyan
W="\[\033[0;37m\]"    # white
EMK="\[\033[1;30m\]"
EMR="\[\033[1;31m\]"
EMG="\[\033[1;32m\]"
EMY="\[\033[1;33m\]"
EMB="\[\033[1;34m\]"
EMM="\[\033[1;35m\]"
EMC="\[\033[1;36m\]"
EMW="\[\033[1;37m\]"
BGK="\[\033[40m\]"
BGR="\[\033[41m\]"
BGG="\[\033[42m\]"
BGY="\[\033[43m\]"
BGB="\[\033[44m\]"
BGM="\[\033[45m\]"
BGC="\[\033[46m\]"
BGW="\[\033[47m\]"

# returns a truncated path (used in prompt)
truncated_pwd () {
  local maxlen=25
  if [[ $PWD == $HOME* ]]; then
    newPWD="~${PWD#$HOME}"
  else
    newPWD=${PWD}
  fi
  if [ ${#newPWD} -gt $maxlen ]; then
    local pwdoffset=$(( ${#newPWD} - $maxlen + 3 ))
    newPWD="…${newPWD:$pwdoffset:$maxlen}"
  fi
  echo $newPWD
}

__git_prompt ()
{
    local g="$(git rev-parse --git-dir 2>/dev/null)"
    if [ -n "$g" ]; then
        local r
        local b
        if [ -d "$g/../.dotest" ]
        then
            if test -f "$g/../.dotest/rebasing"
            then
                r="|REBASE"
            elif test -f "$g/../.dotest/applying"
            then
                r="|AM"
            else
                r="|AM/REBASE"
            fi
            b="$(git symbolic-ref HEAD 2>/dev/null)"
        elif [ -f "$g/.dotest-merge/interactive" ]
        then
            r="|REBASE-i"
            b="$(cat "$g/.dotest-merge/head-name")"
        elif [ -d "$g/.dotest-merge" ]
        then
            r="|REBASE-m"
            b="$(cat "$g/.dotest-merge/head-name")"
        elif [ -f "$g/MERGE_HEAD" ]
        then
            r="|MERGING"
            b="$(git symbolic-ref HEAD 2>/dev/null)"
        else
            if [ -f "$g/BISECT_LOG" ]
            then
                r="|BISECTING"
            fi
            if ! b="$(git symbolic-ref HEAD 2>/dev/null)"
            then
                if ! b="$(git describe --exact-match HEAD 2>/dev/null)"
                then
                    b="$(cut -c1-7 "$g/HEAD")..."
                fi
            fi
        fi

        local git_status="$(git status 2> /dev/null)"

        local remote
        local ahead_pattern="# Your branch is ahead of .* by ([0-9]+) commit"
        local behind_pattern="# Your branch is behind .* by ([0-9]+) commit"
        local diverge_pattern="and have ([0-9]+) and ([0-9]+) different"
        if [[ ${git_status} =~ ${ahead_pattern} ]]; then
            remote="${M}↑${BASH_REMATCH[1]}"
        elif [[ ${git_status} =~ ${behind_pattern} ]]; then
            remote="${B}↓${BASH_REMATCH[1]}"
        elif [[ ${git_status} =~ ${diverge_pattern} ]]; then
            remote="${M}↑${BASH_REMATCH[1]}${Y}↓${BASH_REMATCH[2]}"
        fi

        local state
        if [[ ! ${git_status}} =~ "working directory clean" ]]; then
            state="${R}●"
        fi

        echo " [${b##refs/heads/}$r$remote$state${NONE}]"
    fi
}

bash_prompt() {
    UC=$EMG                     # user's color
    [ $UID -eq "0" ] && UC=$R   # root's color

    # This commented out line shows the pwd in the tab and window bar and stuff,
    # but it confuses the shell a little bit wrt newlines. (Not sure why, since it's
    # surrounded in \[ \])
    # prompt="\[\e]1;$(truncated_pwd)\a\e]2;\u@\h: $PWD\a\]\h:\w$(__git_prompt) \u \$ "
    prompt="\h:\w$(__git_prompt) \u \$ "
    PS1="$prompt"
}
PROMPT_COMMAND=bash_prompt