Ayu Adiati

Posted on Feb 14, 2022 • Edited on Mar 25, 2022 • Originally published at adiati.com

Git: How to fetch a branch from the upstream to the local repo in 5 steps

#github #git #tutorial #codenewbie

Hello Fellow CodeNewbies 👋,

I am collaborating with a friend to create a project in React.
I created a repo for the project, and my teammate forked this repo.

Background

Recently, I created a branch to make some changes. Then I pushed this branch to the remote repo and created a pull request.

I asked my teammate to fetch this branch and test things out locally before merging it into the main branch.
After making sure that we didn't have anything to fetch and merge from the remote repo, and after several attempts, we still couldn't fetch the branch from the remote repo.
We mostly got the error of fatal: couldn't find remote ref <branch-name>.

Then we tried to step back and figure things out.
From my teammate's side, my repo is the upstream repo. He then forked this repo, which automatically becomes his origin repo.
For him to fetch a branch — that hasn't been merged to main — from the upstream repo, his origin repo should have access to the upstream.
So, we need to set the origin repo to point to the upstream repo.

📝 Important Side Notes

My teammate and I started this project with one of us creating a repo and the other forking the repo.
But for collaborating, we could do it differently, which I will cover in another blog post.

We found out later that what we're doing is an open-source workflow, where we maintain and contribute to a repo. In this case, I am the maintainer, and my teammate is the contributor.
However, we learned a lot from this accident.
So, I hope you can gain something too from our journey! 😄

Fetch a branch from the `upstream` repo

Check our current configured remote repo for our fork.
```
  git remote -v
```
If we haven't configured a remote that points to the upstream repo, we will get:
```
 origin <fork-repo-url> (fetch)
 origin <fork-repo-url> (push)
```
Add a new remote upstream repo that will be synced with the
origin repo.
```
git remote add upstream <original-repo-url>
```
original-repo-url is the HTTPS URL of the repo that we fork.

We can copy this link by going to the repo on GitHub, clicking the green button with "Code" written on it, and copying the HTTPS link.

Check if the new upstream has now been added.

git remote -v

Now we should get:

origin <fork-repo-url> (fetch)
origin <fork-repo-url> (push)
upstream <original-repo-url> (fetch)
upstream <original-repo-url> (push)

Fetch data from the upstream.
```
git fetch upstream
```
You will see in the command line that we have fetched the branches on the upstream repo, including the target branch.
Navigate to the branch.
```
git checkout branch-name
```
Running this command will automatically create a branch with the same name in our local repo.