`branch_upstream_remote` says local branch does not exist when it does

[ericswpark]

I have a local git repository with the branch name master that tracks origin/master. I'm trying to write some Rust code to replicate git push && git push --tags.

Here is my code so far:

    let head_ref = repo.head()?.resolve()?;    
    let branch_name = head_ref.shorthand().ok_or_else(|| {
        Error::from_str("Failed to get branch name")
    })?;

    println!("Got branch name {branch_name}");    
    let upstream_remote = repo.branch_upstream_remote(branch_name)?;
    let remote_name = upstream_remote.as_str().ok_or_else(|| {
        Error::from_str("Failed to get remote name")
    })?;
    let mut remote = repo.find_remote(remote_name)?;

    let mut callbacks = RemoteCallbacks::new();
    callbacks.credentials(|_url, _username_from_url, _allowed_types| {
        git2::Cred::ssh_key_from_agent("git")
    });

    let mut push_options = PushOptions::new();
    push_options.remote_callbacks(callbacks);

    remote.push(&[&format!("refs/heads/{}", branch_name)], Some(&mut push_options))?;
    remote.push(&[&format!("refs/tags/{}", &version)], Some(&mut push_options))?;
    // ignore &versions decl -- it is a String that has the tag name in it

When I run the program, however, it panics at the let upstream_remote line, with the following output:

Got branch name master
thread 'main' panicked at src\main.rs:76:xx: Error { code: -1, klass: 3, message: "reference 'master' is not a local branch." }

The error message doesn't make sense, because the previous line of let branch_name got the currently active local branch. Am I calling branch_upstream_remote incorrectly?

[ehuss]

branch_upstream_remote needs it in the form refs/heads/master. Use head_ref.name() instead of shorthand().

[ericswpark]

Great, thank you! That worked. Can this be added to the documentation or is it out of scope?
I can submit a PR if it isn't. Feel free to close the issue otherwise :)

[ehuss]

Yea, it could be added to the docs. There is some risk it will get out of sync with libgit2 if that behavior is ever changed, but it seems like a low risk.