// Copyright 2020 The Jujutsu Authors//// Licensed under the Apache License, Version 2.0 (the "License");// you may not use this file except in compliance with the License.// You may obtain a copy of the License at//// https://www.apache.org/licenses/LICENSE-2.0//// Unless required by applicable law or agreed to in writing, software// distributed under the License is distributed on an "AS IS" BASIS,// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.// See the License for the specific language governing permissions and// limitations under the License. use jj_lib::object_id::ObjectId;use jj_lib::rewrite::back_out_commit;use tracing::instrument; use crate::cli_util::{CommandHelper, RevisionArg};use crate::command_error::CommandError;use crate::ui::Ui; /// Apply the reverse of a revision on top of another revision#[derive(clap::Args, Clone, Debug)]pub(crate) struct BackoutArgs {    /// The revision to apply the reverse of    #[arg(long, short, default_value = "@")]    revision: RevisionArg,    /// The revision to apply the reverse changes on top of    // TODO: It seems better to default this to `@-`. Maybe the working    // copy should be rebased on top?    #[arg(long, short, default_value = "@")]    destination: Vec<RevisionArg>,} #[instrument(skip_all)]pub(crate) fn cmd_backout(    ui: &mut Ui,    command: &CommandHelper,    args: &BackoutArgs,) -> Result<(), CommandError> {    let mut workspace_command = command.workspace_helper(ui)?;    let commit_to_back_out = workspace_command.resolve_single_rev(&args.revision)?;    let mut parents = vec![];    for revision_str in &args.destination {        let destination = workspace_command.resolve_single_rev(revision_str)?;        parents.push(destination);    }    let mut tx = workspace_command.start_transaction();    back_out_commit(        command.settings(),        tx.mut_repo(),        &commit_to_back_out,        &parents,    )?;    tx.finish(        ui,        format!("back out commit {}", commit_to_back_out.id().hex()),    )?;     Ok(())}