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Master to Main branch rename

These instructions will help moving repos from using the default branch name master and modify it to be main.

Prereqs​

First, ensure that the version of git that you have installed is at least v2.28.0. This is important to ensure you have access to the init.DefaultBranch setting in the git config file.

Instructions to change default branch name​

To update the branch name use the npm tool lgarron/main-branch:

npm install -g main-branch
main-branch trussworks/master-to-main-test replace master main

Follow up with local modifications:

cd git-repo-name
git pull origin main
git checkout main
git branch --delete master
git branch --set-upstream-to=origin/main main
git symbolic-ref HEAD refs/heads/main
git symbolic-ref refs/remotes/origin/HEAD refs/remotes/origin/main
git fetch --all --prune

Test that the master branch has been removed by running this command and getting a shell error (exit code not 0):

git checkout master

Future proofing​

If you're using git v2.28.0 or later you should be able to configure git globally to ensure main is now your default branch permanently.

git config --global init.defaultBranch main

Now in your ~/.gitconfig file you'll see this addition:

[init]
    defaultBranch = main

For older versions of the git tool you'll have to be careful to not create new repos with master as the default branch. First make a new git alias:

git config --global alias.main '!git init && git checkout -b main'
git main

You can add an alias to your bash or other shell to help:

alias git_init='git main'

Alternatively use this alias:

alias git_init='git init && git checkout -b main'

Don't forget to source your changes to your shell. For bash you can run: source ~/.bash_profile.

Which gives you the ability to run either git main or git_init to start a new repo with main as the default branch.

Github​

The branch protection rules in Github will need to be modified for each repo that you touch.

Terraform Registry​

Terraform registry uses git tags to pull from github. As long as main is a reflection of master then no changes are needed for the terraform registry.

IDE Changes​

Any ID that handles git integrations should be able to handle this change. Consider adding main to the set of protected branches if your editor allows for that.

Tooling Changes​

As a quick reference for some tools that need to be updated here is a non-exhaustive list:

References​

References: