Set color bash prompt according to git/svn branch, and return status of last command.

git_svn_bash_prompt.sh

#!/bin/bash
#
# DESCRIPTION:
#
#   Set the bash prompt according to:
#    * the branch/status of the current git repository
#    * the branch of the current subversion repository
#    * the return value of the previous command
# 
# USAGE:
#
#   1. Save this file as ~/.git_svn_bash_prompt
#   2. Add the following line to the end of your ~/.profile or ~/.bash_profile:
#        . ~/.git_svn_bash_prompt
#
# AUTHOR:
# 
#   Scott Woods <[email protected]>
#   West Arete Computing
#
#   Based on work by halbtuerke and lakiolen.
#
#   http://gist.github.com/31967
#
#   mcheck:     Added rvm ruby version, adjusted regex for git > 1.8.5 clean status output 
#	
# akom: made rvm options	
# akom: modified colors	
# akom: made compatible with newer git status	
# akom: added a few more git states
# akom: added 'history -a'


# The various escape codes that we can use to color our prompt.
        RED="\[\033[0;31m\]"
     YELLOW="\[\033[0;33m\]"
      GREEN="\[\033[0;32m\]"
       BLUE="\[\033[0;34m\]"
 LIGHT_BLUE="\[\033[1;94m\]"
  LIGHT_RED="\[\033[1;31m\]"
LIGHT_GREEN="\[\033[1;32m\]"
      WHITE="\[\033[1;37m\]"
 LIGHT_GRAY="\[\033[0;37m\]"
 COLOR_NONE="\[\e[0m\]"

# Detect whether the current directory is a git repository.
function is_git_repository {
  git branch > /dev/null 2>&1
}

# Detect whether the current directory is a subversion repository.
function is_svn_repository {
  test -d .svn
}

# Determine the branch/state information for this git repository.
function set_git_branch {
  # Capture the output of the "git status" command.
  git_status="$(git status -s 2> /dev/null)"
  local code=$?

  # Set color based on clean/staged/dirty.
  if [[ ${git_status} == "" ]]; then
    state="${GREEN}"
  else 
    state="${YELLOW}"
  fi
  if [[ ! $code -eq 0 ]] ; then
    state="${RED}"
  fi
  
  # Set arrow icon based on status against remote.
  remote_pattern="[# ]*Your branch is (.*) of"
  if [[ ${git_status} =~ ${remote_pattern} ]]; then
    if [[ ${BASH_REMATCH[1]} == "ahead" ]]; then
      remote="↑"
    else
      remote="↓"
    fi
  else
    remote=""
  fi
  diverge_pattern="[# ]*Your branch and (.*) have diverged"
  if [[ ${git_status} =~ ${diverge_pattern} ]]; then
    remote="↕"
  fi
  
  # Get the name of the branch.
  branch_pattern="^[# ]*On branch ([^${IFS}]*)"    
  if [[ ${git_status} =~ ${branch_pattern} ]]; then
    branch=${BASH_REMATCH[1]}
  fi

  # Set the final branch string.
  BRANCH="${state}(${branch})${remote}${COLOR_NONE} "
}

# Determine the branch information for this subversion repository. No support
# for svn status, since that needs to hit the remote repository.
function set_svn_branch {
  # Capture the output of the "git status" command.
  svn_info="$(svn info | egrep '^URL: ' 2> /dev/null)"

  # Get the name of the branch.
  branch_pattern="^URL: .*/(branches|tags)/([^/]+)"
  trunk_pattern="^URL: .*/trunk(/.*)?$"
  if [[ ${svn_info} =~ $branch_pattern ]]; then
    branch=${BASH_REMATCH[2]}
  elif [[ ${svn_info} =~ $trunk_pattern ]]; then
    branch='trunk'
  fi

  # Set the final branch string.
  BRANCH="(${branch}) "
}

# Return the prompt symbol to use, colorized based on the return value of the
# previous command.
function set_prompt_symbol () {
  if test $1 -eq 0 ; then
      PROMPT_SYMBOL="\$"
  else
      PROMPT_SYMBOL="${RED}\$${COLOR_NONE}"
  fi
}

function parse_ruby_version {
  # ruby -v | cut -d" " -f2    # Pull ruby version from ruby
  [ -x ~/.rvm/bin/rvm-prompt ] && echo "($(~/.rvm/bin/rvm-prompt v p g))"  # Pull ruby and gemset from rvm, check the command to format the response differently
}

# Set the full bash prompt.
function set_bash_prompt () {
  # Set the PROMPT_SYMBOL variable. We do this first so we don't lose the 
  # return value of the last command.
  set_prompt_symbol $?

  # Set the BRANCH variable.
  if is_git_repository ; then
    set_git_branch
  elif is_svn_repository ; then
    set_svn_branch
  else
    BRANCH=''
  fi
  

  # Set the bash prompt variable.
  # AKOM: added colors
  PS1="${GREEN}\u@\h${COLOR_NONE}:${LIGHT_BLUE}\W${COLOR_NONE} $(parse_ruby_version)${BRANCH}${PROMPT_SYMBOL} "

  # AKOM:
  history -a # save this shell's history now
}

# Tell bash to execute this function just before displaying its prompt.
PROMPT_COMMAND=set_bash_prompt