From 3c9933cccedc0fc13dabecd29373a46455aaf46c Mon Sep 17 00:00:00 2001 From: dploch Date: Tue, 17 Sep 2024 08:29:44 -0400 Subject: [PATCH] simplify-parents: add a command to remove redundant parents --- CHANGELOG.md | 2 + cli/src/commands/mod.rs | 5 + cli/src/commands/simplify_parents.rs | 119 +++++++++++++++++ cli/tests/cli-reference@.md.snap | 19 +++ cli/tests/runner.rs | 1 + cli/tests/test_simplify_parents_command.rs | 142 +++++++++++++++++++++ 6 files changed, 288 insertions(+) create mode 100644 cli/src/commands/simplify_parents.rs create mode 100644 cli/tests/test_simplify_parents_command.rs diff --git a/CHANGELOG.md b/CHANGELOG.md index e0c0c21288..c7472cc1c6 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -69,6 +69,8 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html). * `jj commit` and `jj describe` now accept `--author` option allowing to quickly change author of given commit. +* New command `jj simplify-parents` will remove redundant parent edges. + ### Fixed bugs * Update working copy before reporting changes. This prevents errors during reporting diff --git a/cli/src/commands/mod.rs b/cli/src/commands/mod.rs index 52c03c1743..bb8912966b 100644 --- a/cli/src/commands/mod.rs +++ b/cli/src/commands/mod.rs @@ -46,6 +46,7 @@ mod restore; mod root; mod run; mod show; +mod simplify_parents; mod sparse; mod split; mod squash; @@ -145,6 +146,7 @@ enum Command { // TODO: Flesh out. Run(run::RunArgs), Show(show::ShowArgs), + SimplifyParents(simplify_parents::SimplifyParentsArgs), #[command(subcommand)] Sparse(sparse::SparseCommand), Split(split::SplitArgs), @@ -230,6 +232,9 @@ pub fn run_command(ui: &mut Ui, command_helper: &CommandHelper) -> Result<(), Co Command::Revert(_args) => revert(), Command::Root(args) => root::cmd_root(ui, command_helper, args), Command::Run(args) => run::cmd_run(ui, command_helper, args), + Command::SimplifyParents(args) => { + simplify_parents::cmd_simplify_parents(ui, command_helper, args) + } Command::Show(args) => show::cmd_show(ui, command_helper, args), Command::Sparse(args) => sparse::cmd_sparse(ui, command_helper, args), Command::Split(args) => split::cmd_split(ui, command_helper, args), diff --git a/cli/src/commands/simplify_parents.rs b/cli/src/commands/simplify_parents.rs new file mode 100644 index 0000000000..d02cb0d5f9 --- /dev/null +++ b/cli/src/commands/simplify_parents.rs @@ -0,0 +1,119 @@ +use std::collections::HashSet; + +use itertools::Itertools; +use jj_lib::backend::BackendResult; +use jj_lib::revset::RevsetExpression; +use jj_lib::rewrite::CommitRewriter; +use jj_lib::settings::UserSettings; + +use crate::cli_util::CommandHelper; +use crate::cli_util::RevisionArg; +use crate::command_error::CommandError; +use crate::ui::Ui; + +/// Simplify parent edges for the specified revision(s). +/// +/// Removes all redundant parent edges going into any of the specified +/// revisions. By definition, this has no effect on any commit contents and +/// should not cause any working copy changes or conflicts. +/// +/// In other words, for all (A, B, C) where A has (B, C) as parents and C is an +/// ancestor of B, A will be rewritten to have only B as a parent instead of +/// B+C. +#[derive(clap::Args, Clone, Debug)] +#[command(group = clap::ArgGroup::new("revision-args").multiple(true).required(true))] +pub(crate) struct SimplifyParentsArgs { + /// Simplify specified revision(s) together with their trees of descendants + /// (can be repeated) + #[arg(long, short, group = "revision-args")] + sources: Vec, + /// Simplify specified revision(s) (can be repeated) + #[arg(long, short, group = "revision-args")] + revisions: Vec, +} + +pub(crate) fn cmd_simplify_parents( + ui: &mut Ui, + command: &CommandHelper, + args: &SimplifyParentsArgs, +) -> Result<(), CommandError> { + let mut workspace_command = command.workspace_helper(ui)?; + let revs = RevsetExpression::descendants( + workspace_command + .parse_union_revsets(ui, &args.sources)? + .expression(), + ) + .union( + workspace_command + .parse_union_revsets(ui, &args.revisions)? + .expression(), + ); + let commit_ids = workspace_command + .attach_revset_evaluator(revs) + .evaluate_to_commit_ids()? + .collect_vec(); + workspace_command.check_rewritable(&commit_ids)?; + let commit_ids_set: HashSet<_> = commit_ids.iter().cloned().collect(); + let num_orig_commits = commit_ids.len(); + + let mut tx = workspace_command.start_transaction(); + let mut stats = SimplifyStats::default(); + tx.repo_mut() + .transform_descendants(command.settings(), commit_ids, |rewriter| { + if commit_ids_set.contains(rewriter.old_commit().id()) { + simplify_commit_parents(command.settings(), rewriter, &mut stats)?; + } + + Ok(()) + })?; + + if let Some(mut formatter) = ui.status_formatter() { + if !stats.is_empty() { + writeln!( + formatter, + "Removed {} edges from {} out of {} commits.", + stats.edges, stats.commits, num_orig_commits + )?; + } + } + tx.finish(ui, format!("simplify {} commits", num_orig_commits))?; + + Ok(()) +} + +#[derive(Default)] +struct SimplifyStats { + commits: usize, + edges: usize, +} + +impl SimplifyStats { + fn is_empty(&self) -> bool { + self.commits == 0 && self.edges == 0 + } +} + +fn simplify_commit_parents( + settings: &UserSettings, + mut rewriter: CommitRewriter, + stats: &mut SimplifyStats, +) -> BackendResult<()> { + if rewriter.old_commit().parent_ids().len() <= 1 { + return Ok(()); + } + + let num_old_heads = rewriter.new_parents().len(); + rewriter.simplify_ancestor_merge(); + let num_new_heads = rewriter.new_parents().len(); + + if rewriter.parents_changed() { + rewriter.reparent(settings)?.write()?; + + if num_new_heads < num_old_heads { + stats.commits += 1; + stats.edges += num_old_heads - num_new_heads; + } + } + + Ok(()) +} diff --git a/cli/tests/cli-reference@.md.snap b/cli/tests/cli-reference@.md.snap index 5f62cec802..9fc4443261 100644 --- a/cli/tests/cli-reference@.md.snap +++ b/cli/tests/cli-reference@.md.snap @@ -75,6 +75,7 @@ This document contains the help content for the `jj` command-line program. * [`jj restore`↴](#jj-restore) * [`jj root`↴](#jj-root) * [`jj show`↴](#jj-show) +* [`jj simplify-parents`↴](#jj-simplify-parents) * [`jj sparse`↴](#jj-sparse) * [`jj sparse edit`↴](#jj-sparse-edit) * [`jj sparse list`↴](#jj-sparse-list) @@ -139,6 +140,7 @@ To get started, see the tutorial at https://martinvonz.github.io/jj/latest/tutor * `restore` — Restore paths from another revision * `root` — Show the current workspace root directory * `show` — Show commit description and changes in a revision +* `simplify-parents` — Simplify parent edges for the specified revision(s) * `sparse` — Manage which paths from the working-copy commit are present in the working copy * `split` — Split a revision in two * `squash` — Move changes from a revision into another revision @@ -1823,6 +1825,23 @@ Show commit description and changes in a revision +## `jj simplify-parents` + +Simplify parent edges for the specified revision(s). + +Removes all redundant parent edges going into any of the specified revisions. By definition, this has no effect on any commit contents and should not cause any working copy changes or conflicts. + +In other words, for all (A, B, C) where A has (B, C) as parents and C is an ancestor of B, A will be rewritten to have only B as a parent instead of B+C. + +**Usage:** `jj simplify-parents <--sources |--revisions >` + +###### **Options:** + +* `-s`, `--sources ` — Simplify specified revision(s) together with their trees of descendants (can be repeated) +* `-r`, `--revisions ` — Simplify specified revision(s) (can be repeated) + + + ## `jj sparse` Manage which paths from the working-copy commit are present in the working copy diff --git a/cli/tests/runner.rs b/cli/tests/runner.rs index 1420e30cd0..7a7feb763c 100644 --- a/cli/tests/runner.rs +++ b/cli/tests/runner.rs @@ -61,6 +61,7 @@ mod test_revset_output; mod test_root; mod test_shell_completion; mod test_show_command; +mod test_simplify_parents_command; mod test_sparse_command; mod test_split_command; mod test_squash_command; diff --git a/cli/tests/test_simplify_parents_command.rs b/cli/tests/test_simplify_parents_command.rs new file mode 100644 index 0000000000..50e6ee5903 --- /dev/null +++ b/cli/tests/test_simplify_parents_command.rs @@ -0,0 +1,142 @@ +// Copyright 2024 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 std::path::Path; +use std::path::PathBuf; + +use test_case::test_case; + +use crate::common::TestEnvironment; + +fn create_repo() -> (TestEnvironment, PathBuf) { + let test_env = TestEnvironment::default(); + test_env.jj_cmd_ok(test_env.env_root(), &["git", "init", "repo"]); + let repo_path = test_env.env_root().join("repo"); + + (test_env, repo_path) +} + +fn create_commit(test_env: &TestEnvironment, repo_path: &Path, name: &str, parents: &[&str]) { + let mut args = vec!["new", "-m", name]; + args.extend(parents); + test_env.jj_cmd_ok(repo_path, &args); + + std::fs::write(repo_path.join(name), format!("{name}\n")).unwrap(); + test_env.jj_cmd_ok(repo_path, &["bookmark", "create", name]); +} + +#[test] +fn test_simplify_parents_no_args() { + let (test_env, repo_path) = create_repo(); + + let stderr = test_env.jj_cmd_cli_error(&repo_path, &["simplify-parents"]); + insta::assert_snapshot!(stderr, @r###" + error: the following required arguments were not provided: + <--sources |--revisions > + + Usage: jj simplify-parents <--sources |--revisions > + + For more information, try '--help'. + "###); +} + +#[test] +fn test_simplify_parents_no_commits() { + let (test_env, repo_path) = create_repo(); + + let (stdout, stderr) = + test_env.jj_cmd_ok(&repo_path, &["simplify-parents", "-r", "root() ~ root()"]); + insta::assert_snapshot!(stdout, @""); + insta::assert_snapshot!(stderr, @r###" + Nothing changed. + "###); +} + +#[test] +fn test_simplify_parents_immutable() { + let (test_env, repo_path) = create_repo(); + + let stderr = test_env.jj_cmd_failure(&repo_path, &["simplify-parents", "-r", "root()"]); + insta::assert_snapshot!(stderr, @r###" + Error: The root commit 000000000000 is immutable + "###); +} + +#[test] +fn test_simplify_parents_no_change() { + let (test_env, repo_path) = create_repo(); + + create_commit(&test_env, &repo_path, "a", &["root()"]); + create_commit(&test_env, &repo_path, "b", &["a"]); + let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-r", "all()", "-T", "description"]); + insta::assert_snapshot!(stdout, @r###" + @ b + ○ a + ◆ + "###); + + let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["simplify-parents", "-s", "@-"]); + insta::assert_snapshot!(stdout, @""); + insta::assert_snapshot!(stderr, @r###" + Nothing changed. + "###); + + let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-r", "all()", "-T", "description"]); + insta::assert_snapshot!(stdout, @r###" + @ b + ○ a + ◆ + "###); +} + +#[test_case(&["simplify-parents", "-r", "@", "-r", "@-"] ; "revisions")] +#[test_case(&["simplify-parents", "-s", "@-"] ; "sources")] +fn test_simplify_parents_redundant_parent(args: &[&str]) { + let (test_env, repo_path) = create_repo(); + + create_commit(&test_env, &repo_path, "a", &["root()"]); + create_commit(&test_env, &repo_path, "b", &["a"]); + create_commit(&test_env, &repo_path, "c", &["a", "b"]); + let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-r", "all()", "-T", "description"]); + insta::allow_duplicates! { + insta::assert_snapshot!(stdout, @r###" + @ c + ├─╮ + │ ○ b + ├─╯ + ○ a + ◆ + "###); + } + + let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, args); + insta::allow_duplicates! { + insta::assert_snapshot!(stdout, @""); + insta::assert_snapshot!(stderr, @r###" + Removed 1 edges from 1 out of 3 commits. + Working copy now at: royxmykx 0ac2063b c | c + Parent commit : zsuskuln 1394f625 b | b + "###); + } + + let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-r", "all()", "-T", "description"]); + insta::allow_duplicates! { + insta::assert_snapshot!(stdout, @r###" + @ c + ○ b + ○ a + ◆ + "###); + } +}