My Personal PS1 customization to work with git repositories.

.bashrc_ps1.sh

# This bash script will update your PS1 configuration to inform you about:
# - current hour
# - current logged user
# - machine name
# - current path
# - status of current branch: 
#      - untracked files
#      - uncommited changes
#      - when nothing is changed on current branch
# - inform you when the current user.name and user.email is different of the global settings
 
function git_author {
    GIT_AUTHOR_NAME=`git config --get user.name`
    GLOBAL_GIT_AUTHOR_NAME=`git config --global --get user.name`
    GIT_AUTHOR_EMAIL=`git config --get user.email`
    GLOBAL_GIT_AUTHOR_EMAIL=`git config --global --get user.email`
    if [[ ! -z "$GIT_AUTHOR_EMAIL" ]]; then
      if [[ "$GIT_AUTHOR_EMAIL" == "$GLOBAL_GIT_AUTHOR_EMAIL" ]]; then
        GIT_AUTHOR_EMAIL=""
      fi
    else
      GIT_AUTHOR_EMAIL=""
    fi
    if [[ ! -z "$GIT_AUTHOR_NAME" ]]; then
      if [[ "$GIT_AUTHOR_NAME" == "$GLOBAL_GIT_AUTHOR_NAME" ]]; then
        GIT_AUTHOR_NAME=""
      fi
    else
      GIT_AUTHOR_NAME=""
    fi
    GIT_AUTHOR=$GIT_AUTHOR_NAME
    if [[ ! -z "$GIT_AUTHOR_EMAIL" ]]; then
      if [[ ! -z "$GIT_AUTHOR" ]]; then
        GIT_AUTHOR=$GIT_AUTHOR', '
      fi
      GIT_AUTHOR=$GIT_AUTHOR$GIT_AUTHOR_EMAIL
    fi
    if [[ ! -z "$GIT_AUTHOR" ]]; then
      echo "[$GIT_AUTHOR]"
    fi
  }
 
function _git_status() {
    local git_status="`git status -unormal 2>&1`"
    if ! [[ "$git_status" =~ Not\ a\ git\ repo ]]; then
        if [[ "$git_status" =~ nothing\ to\ commit ]]; then
            local color=32
        elif [[ "$git_status" =~ nothing\ added\ to\ commit\ but\ untracked\ files\ present ]]; then
            local color=33
        else
            local color=35
        fi
        echo -n '\[\e[0;'"$color"';1m\]★\[\e[0m\] '
    fi
}
 
function _git_current_branch_branch() {
    local git_status="`git status -unormal 2>&1`"
    if ! [[ "$git_status" =~ Not\ a\ git\ repo ]]; then
        if [[ "$git_status" =~ On\ branch\ ([^[:space:]]+) ]]; then
            branch=${BASH_REMATCH[1]}
            test "$branch" != master || branch=''
        else
            # Detached HEAD.  (branch=HEAD is a faster alternative.)
            branch="(`git describe --all --contains --abbrev=4 HEAD 2> /dev/null ||
                echo HEAD`)"
        fi
 
        if [[ "$branch" != "" ]]; then
          branch=" $branch "
        fi
        echo -n '\[\e[0;37;41;1m\]'"$branch"'\[\e[0m\] '
    fi
}
 
function _prompt_command() {
    PS1=" \t \[\033[0;32m\]\u@\h \[\e[1;33m\]\w \[\e[36m\]`git_author` `_git_current_branch_branch`\n `_git_status`\[\033[0m\]"
}
 
PROMPT_COMMAND=_prompt_command