debug!(
        "repair_context_nondeleted source {:?} target {:?} e {:?}",
        source, target, e
    );

        repair_missing_down_context(txn, channel, ws, inode, target, &[target])?;

        let mut missing_down = std::mem::replace(&mut ws.missing_down, Vec::new());
        missing_down.clear();
        for e in iter_adjacent(
            txn,
            channel,
            target,
            EdgeFlags::DELETED,
            EdgeFlags::all() - EdgeFlags::PARENT,
        )? {
            let e = e?;
            ws.missing_down.push(*txn.find_block(&channel, e.dest())?)
        }
        repair_missing_down_context(txn, channel, ws, inode, target, &missing_down)?;
        ws.missing_down = missing_down;

    missing_down: Vec<Vertex<ChangeId>>,

        self.missing_down.clear();

        assert!(self.missing_down.is_empty());