3.2.1 Setting up

Note: These instructions assume that you are using the command-line version of Git 1.5 or higher. Windows users should skip to Git on Windows.


Installing Git

If you are using a Unix-based machine, the easiest way to download and install Git is through a package manager such as rpm or apt-get – the installation is generally automatic. The only required package is (usually) called git-core, although some of the auxiliary git* packages are also useful (such as gitk).

Alternatively, you can visit the Git website (http://git-scm.com/) for downloadable binaries and tarballs.


Initializing a repository

Once Git is installed, get a copy of the source code:

git clone git://git.sv.gnu.org/lilypond.git ~/lilypond-git

The above command will put the it in ‘~/lilypond-git’, where ~ represents your home directory.

Technical details

This creates (within the ‘$LILYPOND_GIT’ directory) a subdirectory called ‘.git/’, which Git uses to keep track of changes to the repository, among other things. Normally you don’t need to access it, but it’s good to know it’s there.


Configuring Git

Note: Throughout the rest of this manual, all command-line input should be entered from the top directory of the Git repository being discussed (eg. ‘$LILYPOND_GIT’). This is referred to as the top source directory.

Before working with the copy of the main LilyPond repository, you should configure some basic settings with the git config command. Git allows you to set both global and repository-specific options.

To configure settings that affect all repositories, use the ‘--global’ command line option. For example, the first two options that you should always set are your name and email, since Git needs these to keep track of commit authors:

git config --global user.name "John Smith"
git config --global user.email john@example.com

To configure Git to use colored output where possible, use:

git config --global color.ui auto

The text editor that opens when using git commit can also be changed. If none of your editor-related environment variables are set ($GIT_EDITOR, $VISUAL, or $EDITOR), the default editor is usually vi or vim. If you’re not familiar with either of these, you should probably change the default to an editor that you know how to use. For example, to change the default editor to nano, enter:

git config --global core.editor nano

Finally, and in some ways most importantly, let’s make sure that we can easily see the state of our working copy, without the need of typing git status repeatedly. If you’re not using LilyDev, add the following lines to your ‘~/.bashrc’:

export PS1="\u@\h \w\$(__git_ps1)$ "
export GIT_PS1_SHOWDIRTYSTATE=true
export GIT_PS1_SHOWUNTRACKEDFILES=true
export GIT_PS1_SHOWUPSTREAM=auto

The first line will show the branch we’re on. The other lines will use some symbols next to the branch name to indicate some kind of state. “*” means that there are unstaged changes, “+” indicates staged changes; if there are untracked files, a “%” will appear. Finally, we can also see if our HEAD is behind (“<”) or ahead (“>”) of its upstream, and if they have diverged (“<>”) or they are synced (“=”).

You may need to install the additional bash-completion package, but it is definitely worth it. After installation you must log out, and then log back in again to enable it.

Technical details

Git stores the information entered with git config --global in the file ‘.gitconfig’, located in your home directory. This file can also be modified directly, without using git config. The ‘.gitconfig’ file generated by the above commands would look like this:

[user]
        name = John Smith
        email = john@example.com
[color]
        ui = auto
[core]
        editor = nano

Using the git config command without the ‘--global’ option configures repository-specific settings, which are stored in the file ‘.git/config’. This file is created when a repository is initialized (using git init), and by default contains these lines:

[core]
        repositoryformatversion = 0
        filemode = true
        bare = false
        logallrefupdates = true

However, since different repository-specific options are recommended for different development tasks, it is best to avoid setting any now. Specific recommendations will be mentioned later in this manual.


LilyPond — Contributor’s Guide v2.21.0 (development-branch).