====================================
Getting started with Git development
====================================

This section and the next describe in detail how to set up git for working
with the NumPy source code.  If you have git already set up, skip to
:ref:`development-workflow`.

Basic Git setup
###############

* :ref:`install-git`.
* Introduce yourself to Git::

      git config --global user.email you@yourdomain.example.com
      git config --global user.name "Your Name Comes Here"

.. _forking:

Making your own copy (fork) of NumPy
####################################

You need to do this only once.  The instructions here are very similar
to the instructions at http://help.github.com/forking/ - please see that
page for more detail.  We're repeating some of it here just to give the
specifics for the NumPy_ project, and to suggest some default names.

Set up and configure a github_ account
======================================

If you don't have a github_ account, go to the github_ page, and make one.

You then need to configure your account to allow write access - see the
``Generating SSH keys`` help on `github help`_.

Create your own forked copy of NumPy_
=========================================

#. Log into your github_ account.
#. Go to the NumPy_ github home at `NumPy github`_.
#. Click on the *fork* button:

   .. image:: forking_button.png

   After a short pause, you should find yourself at the home page for
   your own forked copy of NumPy_.

.. include:: git_links.inc


.. _set-up-fork:

Set up your fork
################

First you follow the instructions for :ref:`forking`.

Overview
========

::

   git clone https://github.com/your-user-name/numpy.git
   cd numpy
   git remote add upstream git://github.com/numpy/numpy.git

In detail
=========

Clone your fork
---------------

#. Clone your fork to the local computer with ``git clone
   https://github.com/your-user-name/numpy.git``
#. Investigate.  Change directory to your new repo: ``cd numpy``. Then
   ``git branch -a`` to show you all branches.  You'll get something
   like::

      * master
      remotes/origin/master

   This tells you that you are currently on the ``master`` branch, and
   that you also have a ``remote`` connection to ``origin/master``.
   What remote repository is ``remote/origin``? Try ``git remote -v`` to
   see the URLs for the remote.  They will point to your github_ fork.

   Now you want to connect to the upstream `NumPy github`_ repository, so
   you can merge in changes from trunk.

.. _linking-to-upstream:

Linking your repository to the upstream repo
--------------------------------------------

::

   cd numpy
   git remote add upstream git://github.com/numpy/numpy.git

``upstream`` here is just the arbitrary name we're using to refer to the
main NumPy_ repository at `NumPy github`_.

Note that we've used ``git://`` for the URL rather than ``https://``.  The
``git://`` URL is read only.  This means we that we can't accidentally
(or deliberately) write to the upstream repo, and we are only going to
use it to merge into our own code.

Just for your own satisfaction, show yourself that you now have a new
'remote', with ``git remote -v show``, giving you something like::

   upstream	git://github.com/numpy/numpy.git (fetch)
   upstream	git://github.com/numpy/numpy.git (push)
   origin	https://github.com/your-user-name/numpy.git (fetch)
   origin	https://github.com/your-user-name/numpy.git (push)

To keep in sync with changes in NumPy, you want to set up your repository
so it pulls from ``upstream`` by default.  This can be done with::

   git config branch.master.remote upstream
   git config branch.master.merge refs/heads/master

You may also want to have easy access to all pull requests sent to the
NumPy repository::

   git config --add remote.upstream.fetch '+refs/pull//head:refs/remotes/upstream/pr/'

Your config file should now look something like (from
``$ cat .git/config``)::

   [core]
           repositoryformatversion = 0
           filemode = true
           bare = false
           logallrefupdates = true
           ignorecase = true
           precomposeunicode = false
   [remote "origin"]
           url = https://github.com/your-user-name/numpy.git
           fetch = +refs/heads/*:refs/remotes/origin/*
   [remote "upstream"]
           url = git://github.com/numpy/numpy.git
           fetch = +refs/heads/*:refs/remotes/upstream/*
           fetch = +refs/pull/*/head:refs/remotes/upstream/pr/*
   [branch "master"]
           remote = upstream
           merge = refs/heads/master

.. include:: git_links.inc
