Functions to present extra git info on bash prompt.

git_prompt_functions.sh

#!/bin/bash
#  
#  Shows git information in your bash prompt.
#    Git Branch Name
#    Git Dirty State (uncommitted changes)
#    Git "Behind" Count (are you up to date?)
# 
#  =========================================
#   To use:
#   
#   * Put this script into $HOME/bin
#   * Add the following to your $HOME/.bashrc
#    
#     source $HOME/bin/git_prompt_functions.sh
#   * Enjoy
#  =========================================

# ANSI Background Codes
RED_BG="\[\033[41m\]"
BLUE_BG="\[\033[44m\]"

# ANSI Foreground Codes
RED="\[\033[31;1m\]"
GREEN="\[\033[32;1m\]"
YELLOW="\[\033[33;1m\]"
BLUE="\[\033[34;1m\]"
MAGENTA="\[\033[35;1m\]"
CYAN="\[\033[36;1m\]"
WHITE="\[\033[37;1m\]"

# ANSI Other Codes
ANSI_OFF="\[\033[0m\]"

parse_git_branch () 
{ 
    BRANCH_ID=`git branch 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/\1/'`
    if [ -n "$BRANCH_ID" ] ; then
        echo "[$BRANCH_ID$(parse_git_dirty)]"
    fi
}

parse_git_behind ()
{
    git branch --no-color -v 2> /dev/null | \
        sed -e "/^[^*]/d" | \
        grep --color=never -E " \[behind [0-9]*\] " | \
        sed -e "s/.* \[behind \([0-9]*\)\].*/ -\1 /"
}

parse_git_dirty () 
{ 
    git diff --quiet HEAD >&/dev/null;
    [[ $? == 1 ]] && echo "*"
}

export PS1="${BLUE_BG}${BLUE}[${WHITE}\u@\h \W${BLUE}]${YELLOW}\$(parse_git_branch)${RED_BG}${WHITE}\$(parse_git_behind)${ANSI_OFF}$ "