Git Beginners Guide

Beginner’s guide on how to contribute to open source community.

Note

If you don’t have any previous experience with using Git, we recommend you take a 15 minutes long Git Tutorial.

Whether you’re trying to give back to the open source community or collaborating on your own projects, knowing how to properly fork and generate pull requests is essential. Unfortunately, it’s quite easy to make mistakes or not know what you should do when you’re initially learning the process. I know that I certainly had considerable initial trouble with it, and I found a lot of the information on GitHub and around the internet to be rather piecemeal and incomplete - part of the process described here, another there, common hang-ups in a different place, and so on.

This short tutorial is a fairly standard procedure for creating a fork, doing your work, issuing a pull request, and merging that pull request back into the original project.

Create a fork

Just head over to our GitHub page and click the “Fork” button. It’s just that simple. Once you’ve done that, you can use your favorite git client to clone your repo or just head straight to the command line:

git clone git@github.com:<your-username>/<fork-project>

Keep your fork up to date

In most cases, you’ll probably want to make sure you keep your fork up to date by tracking the original “upstream” repo that you forked. To do this, you’ll need to add a remote if not already added:

# Add 'upstream' repo to list of remotes
git remote add upstream git://github.com/NiaOrg/NiaPy.git


# Verify the new remote named 'upstream'
git remote -v

Whenever you want to update your fork with the latest upstream changes, you’ll need to first fetch the upstream repo’s branches and latest commits to bring them into your repository:

# Fetch from upstream remote
git fetch upstream

Now, checkout your own master branch and rebase with the upstream repo’s master branch:

# Checkout your master branch and merge upstream
git checkout master
git merge upstream/master

If there are no unique commits on the local master branch, git will simply perform a fast-forward. However, if you have been making changes on master (in the vast majority of cases you probably shouldn’t be - see the next section Doing your work, you may have to deal with conflicts. When doing so, be careful to respect the changes made upstream.

Now, your local master branch is up-to-date with everything modified upstream.

Doing your work

Create a Branch

Whenever you begin work on a new feature or bug fix, it’s important that you create a new branch. Not only is it proper git workflow, but it also keeps your changes organized and separated from the master branch so that you can easily submit and manage multiple pull requests for every task you complete.

To create a new branch and start working on it:

# Checkout the master branch - you want your new branch to come from master
git checkout master

# Create a new branch named newfeature (give your branch its own simple informative name)
git branch newfeature

# Switch to your new branch
git checkout newfeature

# Last two commands can be joined as following: git checkout -b newfeature

Now, go to town hacking away and making whatever changes you want to.

Submitting a Pull Request

Cleaning Up Your Work

Prior to submitting your pull request, you might want to do a few things to clean up your branch and make it as simple as possible for the original repo’s maintainer to test, accept, and merge your work.

If any commits have been made to the upstream master branch, you should rebase your development branch so that merging it will be a simple fast-forward that won’t require any conflict resolution work.

# Fetch upstream master and merge with your repo's master branch
git fetch upstream
git checkout master
git merge upstream/master

# If there were any new commits, rebase your development branch
git checkout newfeature
git rebase master

Now, it may be desirable to squash some of your smaller commits down into a small number of larger more cohesive commits. You can do this with an interactive rebase:

# Rebase all commits on your development branch
git checkout
git rebase -i master

This will open up a text editor where you can specify which commits to squash.

Submitting

Once you’ve committed and pushed all of your changes to GitHub, go to the page for your fork on GitHub, select your development branch, and click the pull request button. If you need to make any adjustments to your pull request, just push the updates to GitHub. Your pull request will automatically track the changes on your development branch and update.

When pull request is successfully created, make sure you follow activity on your pull request. It may occur that the maintainer of project will ask you to do some more changes or fix something on your pull request before merging it to master branch.

After maintainer merges your pull request to master, you’re done with development on this branch, so you’re free to delete it.

git branch -d newfeature