gitbutlerapp/gitbutler · error

--fix-formatting flag can only be used with commits, not bra

Error message

--fix-formatting flag can only be used with commits, not branches

What it means

`but reword` resolves the target into a branch or a commit; `--fix-formatting` only exists on the commit path (rewrite the message and reformat it), so the branch arm rejects it immediately. Rewording a branch supports renaming and an optional message only.

Source

Thrown at crates/but/src/command/legacy/reword.rs:49

    if message.is_none() && !format && !out.format().allows_human_ui() {
        return Err(bad_input(
            "A message must be provided via --message (-m) for this output format",
        )
        .into());
    }

    let mut guard = ctx.exclusive_worktree_access();
    let id_map = IdMap::new_from_context(ctx, guard.read_permission())?;

    let target = {
        let repo = ctx.repo.get()?;
        target.resolve_in_workspace(&repo, &id_map, Purpose::Target, None)?
    };

    match target.into_branch_or_commit()? {
        BranchOrCommit::Branch(BranchArg(name)) => {
            if format {
                return Err(anyhow::anyhow!(
                    "--fix-formatting flag can only be used with commits, not branches"
                )
                .into());
            }
            if !matches!(show_diff_in_editor, ShowDiffInEditor::Unspecified) {
                return Err(anyhow::anyhow!(
                    "--diff and --no-diff flags can only be used with commits, not branches"
                )
                .into());
            }
            edit_branch_name(ctx, &name, out, message, guard.write_permission())?;
        }
        BranchOrCommit::Commit(commit) => {
            // Rewording a landed commit is lost work: the rewritten commit is
            // dropped again on the next `but pull`.
            MergedUpstream::from_ctx(ctx, allow_merged)?
                .ensure_commit_not_merged(commit.commit_id)?;
            edit_commit_message_by_id_and_reword_commit(

View on GitHub (pinned to caf1f223d3)

Solutions

1. Drop the flag when rewording a branch: `but reword <branch>`
2. Or target a commit instead: `but reword --fix-formatting <sha>`
3. Check `but reword --help` for which flags apply to each target kind

Example fix

# before
but reword --fix-formatting my-branch
# error: --fix-formatting flag can only be used with commits, not branches

# after
but reword my-branch                  # branch rename / message only
but reword --fix-formatting 4a2f9c1   # formatting applies to commits

# Only add --fix-formatting for commit-looking targets
case "$target" in
  *[0-9a-f][0-9a-f][0-9a-f]*) but reword --fix-formatting "$target" ;;  # commit sha
  *)                            but reword "$target" ;;                   # branch
esac

When it happens

Trigger: Running `but reword --fix-formatting <branch>` — the target resolves to `BranchOrCommit::Branch` and the flag check bails.

Common situations: Habit from rewording commits carried over to branch targets; shell history edit changing the target but not the flags.

Related errors

• --diff and --no-diff flags can only be used with commits, no
• Conflicted uncommitted files can only be marked as resolved:
• --ai cannot be combined with a resolve subcommand. For one c
• Cannot use both --detect and --path options together
• Editor exited with non-zero status

AI-assisted analysis of gitbutlerapp/gitbutler@caf1f223d3 (2026-08-20). Data as JSON: /api/errors/ae75e812746d24e1. Report an issue: GitHub.