custom-git-prompt.sh

#!/usr/bin/env bash

# This is a mix of bash-powerline https://github.com/riobard/bash-powerline
# With some stuff from @mathiasbynens's shell prompt which was heavly
# inspired from @necolas’s prompt: https://github.com/necolas/dotfiles

__powerline_git_prompt() {

    # Unicode symbols
    readonly PS_SYMBOL_DARWIN=''
    readonly PS_SYMBOL_LINUX='$'
    readonly PS_SYMBOL_OTHER='%'
    readonly GIT_BRANCH_SYMBOL='⑂ '
    readonly GIT_BRANCH_STAGED_SYMBOL='+'
    readonly GIT_BRANCH_UNSTAGED_SYMBOL='!'
    readonly GIT_BRANCH_UNTRACKED_SYMBOL='?'
    readonly GIT_BRANCH_STASHED_SYMBOL='$'
    readonly GIT_NEED_PUSH_SYMBOL='⇡'
    readonly GIT_NEED_PULL_SYMBOL='⇣'

    # Solarized colorscheme
    readonly FG_BASE03="\[$(tput setaf 8)\]"
    readonly FG_BASE02="\[$(tput setaf 0)\]"
    readonly FG_BASE01="\[$(tput setaf 10)\]"
    readonly FG_BASE00="\[$(tput setaf 11)\]"
    readonly FG_BASE0="\[$(tput setaf 12)\]"
    readonly FG_BASE1="\[$(tput setaf 14)\]"
    readonly FG_BASE2="\[$(tput setaf 7)\]"
    readonly FG_BASE3="\[$(tput setaf 15)\]"

    readonly BG_BASE03="\[$(tput setab 8)\]"
    readonly BG_BASE02="\[$(tput setab 0)\]"
    readonly BG_BASE01="\[$(tput setab 10)\]"
    readonly BG_BASE00="\[$(tput setab 11)\]"
    readonly BG_BASE0="\[$(tput setab 12)\]"
    readonly BG_BASE1="\[$(tput setab 14)\]"
    readonly BG_BASE2="\[$(tput setab 7)\]"
    readonly BG_BASE3="\[$(tput setab 15)\]"

    readonly FG_YELLOW="\[$(tput setaf 3)\]"
    readonly FG_ORANGE="\[$(tput setaf 9)\]"
    readonly FG_RED="\[$(tput setaf 1)\]"
    readonly FG_MAGENTA="\[$(tput setaf 5)\]"
    readonly FG_VIOLET="\[$(tput setaf 13)\]"
    readonly FG_BLUE="\[$(tput setaf 4)\]"
    readonly FG_CYAN="\[$(tput setaf 6)\]"
    readonly FG_GREEN="\[$(tput setaf 2)\]"

    readonly BG_YELLOW="\[$(tput setab 3)\]"
    readonly BG_ORANGE="\[$(tput setab 9)\]"
    readonly BG_RED="\[$(tput setab 1)\]"
    readonly BG_MAGENTA="\[$(tput setab 5)\]"
    readonly BG_VIOLET="\[$(tput setab 13)\]"
    readonly BG_BLUE="\[$(tput setab 4)\]"
    readonly BG_CYAN="\[$(tput setab 6)\]"
    readonly BG_GREEN="\[$(tput setab 2)\]"

    readonly DIM="\[$(tput dim)\]"
    readonly REVERSE="\[$(tput rev)\]"
    readonly RESET="\[$(tput sgr0)\]"
    readonly BOLD="\[$(tput bold)\]"

    GIT_PROMPT_TEXT_COLOR=$FG_BASE3
    GIT_PROMPT_PATH_COLOR=$BG_BASE1$GIT_PROMPT_TEXT_COLOR
    GIT_PROMPT_BRANCH_COLOR=$BG_BLUE$GIT_PROMPT_TEXT_COLOR
    GIT_PROMPT_MARKS_COLOR=$BG_GREEN$GIT_PROMPT_TEXT_COLOR
    GIT_PROMP_BEHIND_COLOR=$BG_RED$GIT_PROMPT_TEXT_COLOR
    GIT_PROMP_AHEAD_COLOR=$BG_GREEN$GIT_PROMPT_TEXT_COLOR

    # what OS?
    case "$(uname)" in
        Darwin)
            readonly PS_SYMBOL=$PS_SYMBOL_DARWIN
            ;;
        Linux)
            readonly PS_SYMBOL=$PS_SYMBOL_LINUX
            ;;
        *)
            readonly PS_SYMBOL=$PS_SYMBOL_OTHER
    esac

    __git_info() {
        [ -x "$(which git)" ] || return    # git not found

        # get current branch name or short SHA1 hash for detached head
        local branch="$(git symbolic-ref --short HEAD 2>/dev/null || git describe --tags --always 2>/dev/null)"
        [ -n "$branch" ] || return  # git branch not found

        local marks

        # Check for uncommitted changes in the index.
        if ! $(git diff --quiet --ignore-submodules --cached); then
          marks+="$GIT_BRANCH_STAGED_SYMBOL";
        fi;

        # Check for unstaged changes.
        if ! $(git diff-files --quiet --ignore-submodules --); then
          marks+="$GIT_BRANCH_UNSTAGED_SYMBOL";
        fi;

        # Check for untracked files.
        if [ -n "$(git ls-files --others --exclude-standard)" ]; then
          marks+="$GIT_BRANCH_UNTRACKED_SYMBOL";
        fi;

        # # Check for stashed files.
        # if $(git rev-parse --verify refs/stash &>/dev/null); then
        #   marks+="$GIT_BRANCH_STASHED_SYMBOL";
        # fi;

        [ -n "${marks}" ] && marks=" [$FG_YELLOW${marks}$RESET]";

        # how many commits local branch is ahead/behind of remote?
        local stat="$(git status --porcelain --branch | grep '^##' | grep -o '\[.\+\]$')"
        local aheadN="$(echo $stat | grep -o 'ahead \d\+' | grep -o '\d\+')"
        local behindN="$(echo $stat | grep -o 'behind \d\+' | grep -o '\d\+')"
        [ -n "$aheadN" ] && ahead=" $GIT_NEED_PUSH_SYMBOL$aheadN"
        [ -n "$behindN" ] && behind=" $GIT_NEED_PULL_SYMBOL$behindN"

        printf "($FG_RED$branch$RESET)$FG_GREEN$ahead$FG_RED$behind$RESET$marks"
    }

    ps1() {
        # Check the exit code of the previous command and display different
        # colors in the prompt accordingly.
        if [ $? -eq 0 ]; then
            local BG_EXIT="$BG_GREEN"
        else
            local BG_EXIT="$BG_RED"
        fi

        PS1="$FG_BASE3\W$RESET"
        PS1+="$FG_BASE3$(__git_info) $RESET"
        PS1+="$BOLD$FG_RED$PS_SYMBOL_LINUX $RESET"
    }

    export PROMPT_COMMAND=ps1
}

__powerline_git_prompt
unset __powerline_git_prompt