Deleting your master branch

You’ve forked some project on github.

You clone your fork.

Now you’ve got a master branch. It’s the master branch of your fork.

It can be tempting to do work in the master branch and ask for a pull request.

That is best avoided because:

• It’s natural to carry on working in your master and that will pollute your pull request with other commits
• master is not a descriptive name for a set of changes. It’s easier for the person reviewing your code to have something like fix-for-issue-12.
• You may well also have a tracking branch pointing to the main upstream repo. You might call that something like upstream-master. It’s easy to lose concentration and forget you are on upstream-master instead of your master, and nasty errors can result.

To avoid this, I delete the master branch from my forked copy. However, to make that work, you have to tell github not to monitor your master branch.

How to delete master

First you delete master in your local clone. To do this we first make a new branch called placeholder or similar, and delete master from there:

git branch placeholder
git checkout placeholder
git branch -D master

All good so far. We next want to delete the branch on github. However, if we do this the naive way:

git push origin :master

we just get an error like this:

remote: error: refusing to delete the current branch: refs/heads/master
To git@github.com:matthew-brett/datarray.git
! [remote rejected] master (deletion of the current branch prohibited)
error: failed to push some refs to 'git@github.com:matthew-brett/datarray.git'

That is because github is looking at the master branch to provide the web content when you browse that repository. So we first have to make github look at our placeholder branch instead, then delete master.

First push up the placeholder branch:

git checkout placeholder # if not on placeholder already
git push origin placeholder

Then set placeholder to be the github default branch. Go to the main github page for your forked repository, and click on the “Admin” button.

There’s a “Default branch” dropdown list near the top of the screen. From there, select placeholder. On the interface I’m looking at, a green tick appears above the dropdown list. Now you can do (from the command line):

git push origin :master

and - no master branch...