Summary

Using GitHub CLI gh ( https://github.com/cli/cli ), I often checkout pull-request.

gh pr checkout 330

But go-git fails to parse the config in the repository that has a branch created by gh.

To reproduce:

1. Prepare a repository

$ git clone https://github.com/go-git/go-git
$ gh pr checkout 330

2. Try to get the remote URLs from the repository with go-git

	repo, err := git.PlainOpen("./go-git")
	if err != nil {
		return nil, fmt.Errorf("open local repository: %w", err)
	}
	remote, err := repo.Remote("origin")
	if err != nil {
		return nil, fmt.Errorf("get remote %s: %w", name, err)
	}
	return remote.Config().URLs, nil

It fails.

Supplement

gh pr checkout xxx creates a branch like below.

[branch "foo/bar"]
	remote = origin
	merge = refs/pull/330/head

go-git says "branch config: invalid merge".