vcs-bash-prompt

My custom bash prompt using Version Control Systems (VCS) such as: git, hg, ecc...

Introduction

When I work with VCS at bash command line, on my favorite GNU/Linux distribution, I find useful a custom prompt that display information about the VCS used in a project.

When I am in any directory of a project's directory tree the custom prompt display me:

• which VCS is being used
• which branch I am on

Many thanks to this Tom Ryder's post.

Code

At the end of my .bashrc file I have added this four functions:

prompt_git() {
    $(git rev-parse --is-inside-git-dir 2>/dev/null ) \
        && return 1
    $(git rev-parse --is-inside-work-tree 2>/dev/null ) \
        || return 1
    git status &>/dev/null
    branch=$(git symbolic-ref --quiet HEAD 2>/dev/null ) \
        || branch=$(git rev-parse --short HEAD 2>/dev/null ) \
        || branch='unknown'
    branch=${branch##*/}
    git diff --quiet --ignore-submodules --cached \
        || state=${state}+
    git diff-files --quiet --ignore-submodules -- \
        || state=${state}!
    $(git rev-parse --verify refs/stash &>/dev/null ) \
        && state=${state}^
    [ -n "$(git ls-files --others --exclude-standard )" ] \
        && state=${state}?
    printf '(git:%s)' "${branch:-unknown}${state}"
}
prompt_hg() {
    hg branch &>/dev/null || return 1
    BRANCH="$(hg branch 2>/dev/null)"
    [[ -n "$(hg status 2>/dev/null)" ]] && STATUS="!"
    printf '(hg:%s)' "${BRANCH:-unknown}${STATUS}"
}
prompt_svn() {
    svn info &>/dev/null || return 1
    URL="$(svn info 2>/dev/null | \
        awk -F': ' '$1 == "URL" {print $2}')"
    ROOT="$(svn info 2>/dev/null | \
        awk -F': ' '$1 == "Repository Root" {print $2}')"
    BRANCH=${URL/$ROOT}
    BRANCH=${BRANCH#/}
    BRANCH=${BRANCH#branches/}
    BRANCH=${BRANCH%%/*}
    [[ -n "$(svn status 2>/dev/null)" ]] && STATUS="!"
    printf '(svn:%s)' "${BRANCH:-unknown}${STATUS}"
}
prompt_vcs() {
    prompt_hg || prompt_git || prompt_svn 
}

Because these functions call your VCS program (git, hg, svn) you have to add your VCS to your PATH variable.

Then I have looked for PS1 in my .bashrc and I have changed the setting to the following one where I have introduced the call to the prompt_vcs function:

PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w$(prompt_vcs)\$ '

That is all.

Adding some color

Probably your .bashrc lets you choose a colored prompt. In that case simply introduce the call to the prompt_vcs function to both the PS1 setting lines:

if [ "$color_prompt" = yes ]; then
    PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\[\033[01;33m\]$(prompt_vcs)\[\033[00m\]\$ '
else
    PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w$(prompt_vcs)\$ '
fi

In the following screenshot you can see my custom prompt when I work on JugEvents3 with hg and when I work on SemVer with git: