// 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::commit::Commit;use jj_lib::dag_walk::topo_order_reverse;use jj_lib::matchers::EverythingMatcher;use jj_lib::rewrite::rebase_to_dest_parent;use tracing::instrument; use crate::cli_util::{CommandHelper, LogContentFormat, RevisionArg, WorkspaceCommandHelper};use crate::command_error::CommandError;use crate::diff_util::{self, DiffFormat, DiffFormatArgs};use crate::formatter::Formatter;use crate::graphlog::{get_graphlog, Edge};use crate::ui::Ui; /// Show how a change has evolved////// Show how a change has evolved as it's been updated, rebased, etc.#[derive(clap::Args, Clone, Debug)]pub(crate) struct ObslogArgs {    #[arg(long, short, default_value = "@")]    revision: RevisionArg,    /// Limit number of revisions to show    #[arg(long, short)]    limit: Option<usize>,    /// Don't show the graph, show a flat list of revisions    #[arg(long)]    no_graph: bool,    /// Render each revision using the given template    ///    /// For the syntax, see https://github.com/martinvonz/jj/blob/main/docs/templates.md    #[arg(long, short = 'T')]    template: Option<String>,    /// Show patch compared to the previous version of this change    ///    /// If the previous version has different parents, it will be temporarily    /// rebased to the parents of the new version, so the diff is not    /// contaminated by unrelated changes.    #[arg(long, short = 'p')]    patch: bool,    #[command(flatten)]    diff_format: DiffFormatArgs,} #[instrument(skip_all)]pub(crate) fn cmd_obslog(    ui: &mut Ui,    command: &CommandHelper,    args: &ObslogArgs,) -> Result<(), CommandError> {    let workspace_command = command.workspace_helper(ui)?;     let start_commit = workspace_command.resolve_single_rev(&args.revision)?;    let wc_commit_id = workspace_command.get_wc_commit_id();     let diff_formats =        diff_util::diff_formats_for_log(command.settings(), &args.diff_format, args.patch)?;     let template_string = match &args.template {        Some(value) => value.to_string(),        None => command.settings().config().get_string("templates.log")?,    };    let template = workspace_command.parse_commit_template(&template_string)?;    let with_content_format = LogContentFormat::new(ui, command.settings())?;     ui.request_pager();    let mut formatter = ui.stdout_formatter();    let formatter = formatter.as_mut();    formatter.push_label("log")?;     let mut commits = topo_order_reverse(        vec![start_commit],        |commit: &Commit| commit.id().clone(),        |commit: &Commit| commit.predecessors(),    );    if let Some(n) = args.limit {        commits.truncate(n);    }    if !args.no_graph {        let mut graph = get_graphlog(command.settings(), formatter.raw());        let default_node_symbol = graph.default_node_symbol().to_owned();        for commit in commits {            let mut edges = vec![];            for predecessor in &commit.predecessors() {                edges.push(Edge::Direct(predecessor.id().clone()));            }            let mut buffer = vec![];            with_content_format.write_graph_text(                ui.new_formatter(&mut buffer).as_mut(),                |formatter| template.format(&commit, formatter),                || graph.width(commit.id(), &edges),            )?;            if !buffer.ends_with(b"\n") {                buffer.push(b'\n');            }            if !diff_formats.is_empty() {                let mut formatter = ui.new_formatter(&mut buffer);                show_predecessor_patch(                    ui,                    formatter.as_mut(),                    &workspace_command,                    &commit,                    &diff_formats,                )?;            }            let node_symbol = if Some(commit.id()) == wc_commit_id {                "@"            } else {                &default_node_symbol            };            graph.add_node(                commit.id(),                &edges,                node_symbol,                &String::from_utf8_lossy(&buffer),            )?;        }    } else {        for commit in commits {            with_content_format                .write(formatter, |formatter| template.format(&commit, formatter))?;            if !diff_formats.is_empty() {                show_predecessor_patch(ui, formatter, &workspace_command, &commit, &diff_formats)?;            }        }    }     Ok(())} fn show_predecessor_patch(    ui: &Ui,    formatter: &mut dyn Formatter,    workspace_command: &WorkspaceCommandHelper,    commit: &Commit,    diff_formats: &[DiffFormat],) -> Result<(), CommandError> {    let predecessors = commit.predecessors();    let predecessor = match predecessors.first() {        Some(predecessor) => predecessor,        None => return Ok(()),    };    let predecessor_tree =        rebase_to_dest_parent(workspace_command.repo().as_ref(), predecessor, commit)?;    let tree = commit.tree()?;    diff_util::show_diff(        ui,        formatter,        workspace_command,        &predecessor_tree,        &tree,        &EverythingMatcher,        diff_formats,    )}