Function revert_step 

pub fn revert_step(
    doc: &mut AutoCommit,
    change: &ChangeHash,
    by: Option<&str>,
    authors: &dyn ResolveAuthor,
) -> Result<RevertOutcome, RevertError>

Undo one entry’s share of a run of work by writing its inverse forward into doc: revert_run for a run of one change, which is what a step of an agent’s run names (the toolkit’s RunStep).

This is the step the reader’s history takes back, and it is the same one undo publishes: a run undone by an agent’s report and one undone by Ctrl+Z write the same inverse, through the same classification of what a later writer has since changed.

The transaction is left open, as with revert_run: the caller commits.

Errors

Propagates RevertError from run_bounds when the change cannot be addressed in doc.