Error: UnbornBranch

[tkellogg]

Repro

• Run dura serve
• Create a new repo, e.g. with cargo new, and make changes without committing
• Check the stdout log, there should be errors that look like:

{"target":"dura::poller","file":"src/poller.rs","name":"event src/poller.rs:41","level":"Level(Info)","fields":{"message":"info_operation","operation":{"Snapshot":{"error":"reference 'refs/heads/master' not found; class=Reference (4); code=UnbornBranch (-9)","latency":0.000267355,"op":null,"repo":"/Users/timkellogg/code/oss/syndr"}}},"time":"2022-11-28T14:27:18.611085+00:00"}

Expected behavior

This happens when there's no first commit. Normally the branch name is dura_{base_commit_hash}, in this case we could make it a constant dura_unborn or dura_init.

This also means that the first commit in sequence might not have a parent, which may cause other problems.

[Amanse]

I am not as familiar with the code base, but as far as i understand, changing in src/snapshots.rs for branch name to be something else should work, but how would you want the parent commit handled? it could be made into an Option<> or maybe error handled when it is needed some other way

[tkellogg]

Ah! Git trivia time! The parent commit is a plain list of commit hashes.

• 0 commits = first commit
• 1 commit = the normal case
• 2 commits = merge commit
• 3+ commits = octopus merge

So yeah, it's as simple as giving it an empty slice.

[Amanse]

love your style haha
i will try this tomorrow(in about ~12 hours)
have really taken a liking to this project 😄

[Amanse]

If dura makes the first commit would that set the dura_unborn as the default branch?
also i am thinking something like this to error handle the head, but it doesn't seem elegant

let head = match repo.head() {
        Ok(v) => peel_to_commit(v)?,
        Err(e) => if e.code() == git2::UnbornBranch {
            // handle unborn branch
        } else {
            return Err(e);
        }
    }
}

[tkellogg]

I don't know. Write a test and find out!

[Amanse]

I went the way of making head: Option<git2::Commit> which seemed logical as it can None when there is no head
but this has an adverse effect that all the statements in the capture function need to be if let Some(h) = head and it then extends to parent_commit being an option because git2 doesn't support empty slice as a parent, and the if let Some hell extends to it too.

I am thinking that once we check if head exists or not, it can be divided into 2 capture functions. Once dura makes the commit in the unborn_capture function it will have a head to use and will no longer fall back on that function.