2014-06-26

github fork a repo branch

link
I don’t know a native way yet, but you can do it following this recipe:

Fork the repository in question (called ‘upstream’) on the GitHub website to your workspace there.
Run the GitHub desktop application and clone the repository onto your PC.
Use the GitHub desktop application to open a shell in the repository. (The git commands are not available from the default PowerShell unless you configure that manually.)

Set the source repository as upstream:

git remote add upstream https://github.com/{user}/{source-repo}.git

Fetch the full upstream repository. (Right now, you only have a copy of its master branch.)
```
git fetch upstream
```

Make your file system copy the branch you want and give it any name:

git checkout upstream/{branch-in-question}
git checkout -b temporary

Publish your repo using the GitHub desktop application.
On the GitHub website, open your repository and click ‘settings’.
Change the “Default branch” to ‘temporary’. (Just change the drop-down menu, you don’t need to click the “Rename” button.)
Go back to your repository, go to the ‘branches’ tab, now you can delete the “master” branch.

Delete the master branch on your shell and make a new master branch:

git branch -d master
git branch master
git checkout master
git -d temporary

Once more, publish your repo using the GitHub desktop application.
On the GitHub website, open your repository and click ‘settings’.
Change the “Default branch” back to the (new) ‘master’ branch.
Go back to your repository, go to the ‘branches’ tab, now you can delete the “temporary” branch.

This should be what you were looking for. Perhaps GitHub will provide a more convenient way to do this in future (e.g., clicking “Fork” from a project’s branch results in exactly this behaviour).