dbt-labs/dbt-core · error

--commit-author and --commit-email must be set together

Error message

--commit-author and --commit-email must be set together

What it means

When committing the formula update to the tap repository, the commit author identity can optionally be overridden via `--commit-author` and `--commit-email`. `run` enforces that these two options are always supplied together: providing exactly one leaves git's user config half-specified, so the command bails with a descriptive message. Providing neither is allowed, in which case the inherited git identity is used.

Source

Thrown at crates/dbt-ci/src/homebrew/publish.rs:97

    fs::copy(&args.formula, &dest)
        .with_context(|| format!("copy {} -> {}", args.formula.display(), dest.display()))?;

    let status = run_git_capture(Some(work.path()), &["status", "--porcelain"])?;
    if status.trim().is_empty() {
        eprintln!("✓ {} already up to date in tap", filename);
        return Ok(());
    }

    // Only override identity if BOTH flags are provided. Otherwise inherit
    // whatever git config the cloned tap has — which on a dev machine comes
    // from `~/.gitconfig`.
    match (&args.commit_author, &args.commit_email) {
        (Some(name), Some(email)) => {
            run_git(Some(work.path()), &["config", "user.name", name])?;
            run_git(Some(work.path()), &["config", "user.email", email])?;
        }
        (None, None) => {} // inherit
        _ => bail!("--commit-author and --commit-email must be set together"),
    }

    run_git(Some(work.path()), &["add", &format!("Formula/{filename}")])?;
    let message = format!(
        "{stem} {version}",
        stem = filename.trim_end_matches(".rb"),
        version = args.version,
    );
    run_git(Some(work.path()), &["commit", "-m", &message])?;

    if args.dry_run {
        eprintln!("→ dry-run: skipping push. Patch follows:\n");
        run_git(Some(work.path()), &["--no-pager", "show", "HEAD"])?;
        return Ok(());
    }

    // Push needs the same `-c http.extraHeader=…` knobs as clone.
    let mut push_argv: Vec<OsString> = auth_args;

View on GitHub (pinned to 0267ce9170)

Solutions

1. Pass both flags together: `--commit-author "Bot Name" --commit-email bot@example.com`.
2. If you want the default git identity, remove both flags and let the tap repo's configured user.name/user.email apply.
3. Fix the CI template/workflow so both values are sourced together (e.g., from the same bot identity config).

Example fix

// before
dbt-ci homebrew publish --formula Formula/dbt.rb --commit-author "Release Bot"
// after
dbt-ci homebrew publish --formula Formula/dbt.rb --commit-author "Release Bot" --commit-email bot@example.com

fn validate_commit_identity(author: &Option<String>, email: &Option<String>) -> Result<(), String> {
    match (author, email) {
        (Some(_), Some(_)) | (None, None) => Ok(()),
        _ => Err("--commit-author and --commit-email must be set together".to_string()),
    }
}

match publish(args) {
    Err(e) if e.to_string().contains("must be set together") => {
        eprintln!("Supply both --commit-author and --commit-email, or neither.");
        std::process::exit(2);
    }
    Err(e) => return Err(e),
    Ok(v) => Ok(v),
}

When it happens

Trigger: Running `dbt-ci homebrew publish` with `--commit-author <name>` but no `--commit-email`, or `--commit-email <email>` but no `--commit-author`.

Common situations: CI templating that fills one variable but not the other (e.g., a secrets/config map containing the bot name but not the email); a developer hand-typing the flags and forgetting the pair; scripts updated to add an author override without updating the email.

Understand the failure class

Background: "mutually exclusive" flag errors: what "can't supply both nx and xx", "--raw is not compatible with -i" and "cannot be used with" mean, and how to fix them — this error's family across 29 libraries.

Related errors

• formula file not found: {}
• formula filename does not end in .rb: {filename}
• --download-base-url requires at least one --target
• `git {}` exited with status {}
• SemVer build metadata not supported in {semver:?}

AI-assisted analysis of dbt-labs/dbt-core@0267ce9170 (2026-09-07). Data as JSON: /api/errors/b795d5b30996c9ce. Report an issue: GitHub.