/// Record the change in this channel instead of the current channel

        /// Tag the current state of this channel instead of the
        /// current channel.

        /// Set the repository where this command should run. Defaults to
        /// the first ancestor of the current directory that contains a
        /// `.pijul` directory.
        #[clap(long = "repository")]
        repo_path: Option<PathBuf>,
        tag: String,
    },
    /// Delete a tag from a channel. If the same state isn't tagged in
    /// other channels, delete the tag file.
    #[clap(name = "delete")]
    Delete {

        /// Delete the tag in this channel instead of the current channel
        #[clap(long = "channel")]
        channel: Option<String>,

            }
            Some(SubCommand::Delete {
                repo_path,
                channel,
                tag,
            }) => {
                let repo = Repository::find_root(repo_path)?;
                let mut tag_path = repo.changes_dir.clone();
                let h = if let Some(h) = libpijul::Merkle::from_base32(tag.as_bytes()) {
                    libpijul::changestore::filesystem::push_tag_filename(&mut tag_path, &h);
                    h
                } else {
                    super::find_hash(&mut tag_path, &tag)?
                };
                let mut txn = repo.pristine.mut_txn_begin()?;
                let channel_name = channel.unwrap_or_else(|| {
                    txn.current_channel()
                        .unwrap_or(crate::DEFAULT_CHANNEL)
                        .to_string()
                });
                let channel = if let Some(c) = txn.load_channel(&channel_name)? {
                    c
                } else {
                    bail!("Channel {:?} not found", channel_name)
                };
                {
                    let mut ch = channel.write();
                    if let Some(n) = txn.channel_has_state(txn.states(&*ch), &h.into())? {
                        let tags = txn.tags_mut(&mut *ch);
                        txn.del_tags(tags, n.into())?;
                    }
                }
                txn.commit()?;
                writeln!(stdout, "Deleted tag {}", h.to_base32())?;