// 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::collections::HashMap;use std::io::Write as _;use std::path::Path;use std::process::Stdio; use clap_complete::ArgValueCompleter;use itertools::Itertools as _;use jj_lib::backend::FileId;use jj_lib::commit::Commit;use jj_lib::fileset;use jj_lib::fileset::FilesetDiagnostics;use jj_lib::fileset::FilesetExpression;use jj_lib::fileset::FilesetParseContext;use jj_lib::fix::FileToFix;use jj_lib::fix::FixError;use jj_lib::fix::ParallelFileFixer;use jj_lib::fix::fix_files;use jj_lib::matchers::Matcher;use jj_lib::repo::Repo as _;use jj_lib::repo_path::RepoPathUiConverter;use jj_lib::revset::RevsetIteratorExt as _;use jj_lib::settings::UserSettings;use jj_lib::store::Store;use pollster::FutureExt as _;use tokio::io::AsyncReadExt as _;use tracing::instrument; use crate::cli_util::CommandHelper;use crate::cli_util::RevisionArg;use crate::cli_util::print_unmatched_explicit_paths;use crate::command_error::CommandError;use crate::command_error::config_error;use crate::command_error::print_parse_diagnostics;use crate::complete;use crate::config::CommandNameAndArgs;use crate::ui::Ui; /// Update files with formatting fixes or other changes////// The primary use case for this command is to apply the results of automatic/// code formatting tools to revisions that may not be properly formatted yet./// It can also be used to modify files with other tools like `sed` or `sort`.////// The modification made by `jj fix` can be reviewed by `jj op show -p`.////// ### How it works////// The changed files in the given revisions will be updated with any fixes/// determined by passing their file content through any external tools the user/// has configured for those files. Descendants will also be updated by passing/// their versions of the same files through the same tools, which will ensure/// that the fixes are not lost. This will never result in new conflicts. Files/// with existing conflicts will be updated on all sides of the conflict, which/// can potentially increase or decrease the number of conflict markers.////// ### Deduplication////// When fixing multiple commits, if the same file content appears at the same/// path in different commits, the tool is run only once and the result is/// reused. This means that tools used with `jj fix` must produce deterministic/// output.////// ### Configuration////// See `jj help -k config` chapter `Code formatting and other file content/// transformations` to understand how to configure your tools.////// ### Execution Example////// Let's consider the following configuration is set. We have two code/// formatters (`clang-format` and `black`), which apply to three different/// file extensions (`.cc`, `.h`, and `.py`):////// ```toml/// [fix.tools.clang-format]/// command = ["/usr/bin/clang-format", "--assume-filename=$path"]/// patterns = ["glob:'**/*.cc'",///             "glob:'**/*.h'"]////// [fix.tools.black]/// command = ["/usr/bin/black", "-", "--stdin-filename=$path"]/// patterns = ["glob:'**/*.py'"]/// ```////// Now, let's see what would happen to the following history, when executing/// `jj fix`.////// ```text/// C (mutable)/// |  Modifies file: foo.py/// |/// B @ (working copy - mutable)/// |  Modifies file: README.md/// |/// A (mutable)/// |  Modifies files: src/bar.cc and src/bar.h/// |/// X (immutable)/// ```////// By default, `jj fix` will modify revisions that matches the revset/// `reachable(@, mutable())` (see `jj help -k revsets`) which corresponds to/// the revisions `A`, `B` and `C` here.////// The following operations will then happen:////// - For revision `A`, content from this revision for files `src/bar.cc` and///   `src/bar.h` will each be provided to `clang-format` and the result output///   will be used to recreate revision `A` which we will call `A'`. All other///   files are untouched./// - For revision `B`, same thing happen for files `src/bar.cc` and `src/bar.h`///   Their content from revision `B` will go through `clang-format`. The file///   `README.md` as any other files, are untouched as no pattern matches it. We///   obtain revision `B'`./// - For revision `C`, `src/bar.cc` and `src/bar.h` goes through `clang-format`///   and file `foo.py` is fixed using `black`. Any other file is untouched. We///   obtain revision `C'`.////// ```text/// C (mutable)                    /-> C'/// |  src/bar.cc -> clang-format -|   |/// |  src/bar.h --> clang-format -|   |/// |  foo.py -----> black --------|   |/// |  * --------------------------/   |/// |                                  |/// B @ (working copy - mutable)   /-> B' @/// |  src/bar.cc -> clang-format -|   |/// |  src/bar.h --> clang-format -|   |/// |  * --------------------------|   |/// |                                  |/// A (mutable)                    /-> A'/// |  src/bar.cc -> clang-format -|   |/// |  src/bar.h --> clang-format -|   |/// |  * --------------------------/   |/// |                                  |/// X (immutable)                      X/// ```////// The revisions are now all correctly formatted according to the/// configuration.#[derive(clap::Args, Clone, Debug)]#[command(verbatim_doc_comment)]pub(crate) struct FixArgs {    /// Fix files in the specified revision(s) and their descendants. If no    /// revisions are specified, this defaults to the `revsets.fix` setting, or    /// `reachable(@, mutable())` if it is not set.    #[arg(long, short, value_name = "REVSETS")]    #[arg(add = ArgValueCompleter::new(complete::revset_expression_mutable))]    source: Vec<RevisionArg>,     /// Fix only these paths    #[arg(value_name = "FILESETS", value_hint = clap::ValueHint::AnyPath)]    paths: Vec<String>,     /// Fix unchanged files in addition to changed ones. If no paths are    /// specified, all files in the repo will be fixed.    #[arg(long)]    include_unchanged_files: bool,} #[instrument(skip_all)]pub(crate) async fn cmd_fix(    ui: &mut Ui,    command: &CommandHelper,    args: &FixArgs,) -> Result<(), CommandError> {    let mut workspace_command = command.workspace_helper(ui)?;    let workspace_root = workspace_command.workspace_root().to_owned();    let path_converter = workspace_command.path_converter().to_owned();    let tools_config = get_tools_config(        ui,        workspace_command.settings(),        &workspace_command.env().fileset_parse_context_for_config(),    )?;    let target_expr = if args.source.is_empty() {        let revs = workspace_command.settings().get_string("revsets.fix")?;        workspace_command.parse_revset(ui, &RevisionArg::from(revs))?    } else {        workspace_command.parse_union_revsets(ui, &args.source)?    }    .resolve()?;    workspace_command.check_rewritable_expr(&target_expr)?;     let repo = workspace_command.repo();     let commits: Vec<Commit> = target_expr        .descendants()        .evaluate(repo.as_ref())?        .iter()        .commits(repo.store())        .try_collect()?;     let commit_ids = commits        .iter()        .map(|commit| commit.id().clone())        .collect_vec();     let trees: Vec<_> = commits.iter().map(|commit| commit.tree()).collect();     let fileset_expression = workspace_command.parse_file_patterns(ui, &args.paths)?;    let matcher = fileset_expression.to_matcher();     let mut tx = workspace_command.start_transaction();    let mut parallel_fixer = ParallelFileFixer::new(|store, file_to_fix| {        fix_one_file(            ui,            &workspace_root,            &path_converter,            &tools_config,            store,            file_to_fix,        )        .block_on()    });     print_unmatched_explicit_paths(ui, tx.base_workspace_helper(), &fileset_expression, &trees)?;     let summary = fix_files(        commit_ids,        &matcher,        args.include_unchanged_files,        tx.repo_mut(),        &mut parallel_fixer,    )    .await?;    writeln!(        ui.status(),        "Fixed {} commits of {} checked.",        summary.num_fixed_commits,        summary.num_checked_commits    )?;    tx.finish(ui, format!("fixed {} commits", summary.num_fixed_commits))} /// Invokes all matching tools (if any) to file_to_fix. If the content is/// successfully transformed the new content is written and the new FileId is/// returned. Returns None if the content is unchanged.////// The matching tools are invoked in order, with the result of one tool feeding/// into the next tool. Returns FixError if there is an error reading or writing/// the file. However, if a tool invocation fails for whatever reason, the tool/// is simply skipped and we proceed to invoke the next tool (this is/// indistinguishable from succeeding with no changes).////// TODO: Better error handling so we can tell the user what went wrong with/// each failed input.async fn fix_one_file(    ui: &Ui,    workspace_root: &Path,    path_converter: &RepoPathUiConverter,    tools_config: &ToolsConfig,    store: &Store,    file_to_fix: &FileToFix,) -> Result<Option<FileId>, FixError> {    let mut matching_tools = tools_config        .tools        .iter()        .filter(|tool_config| tool_config.matcher.matches(&file_to_fix.repo_path))        .peekable();    if matching_tools.peek().is_some() {        // The first matching tool gets its input from the committed file, and any        // subsequent matching tool gets its input from the previous matching tool's        // output.        let mut old_content = vec![];        let mut read = store            .read_file(&file_to_fix.repo_path, &file_to_fix.file_id)            .await?;        read.read_to_end(&mut old_content).await?;        let new_content = matching_tools.fold(old_content.clone(), |prev_content, tool_config| {            match run_tool(                ui,                workspace_root,                path_converter,                &tool_config.command,                file_to_fix,                &prev_content,            ) {                Ok(next_content) => next_content,                // TODO: Because the stderr is passed through, this isn't always failing                // silently, but it should do something better will the exit code, tool                // name, etc.                Err(()) => prev_content,            }        });        if new_content != old_content {            // TODO: send futures back over channel            let new_file_id = store                .write_file(&file_to_fix.repo_path, &mut new_content.as_slice())                .await?;            return Ok(Some(new_file_id));        }    }    Ok(None)} /// Runs the `tool_command` to fix the given file content.////// The `old_content` is assumed to be that of the `file_to_fix`'s `FileId`, but/// this is not verified.////// Returns the new file content, whose value will be the same as `old_content`/// unless the command introduced changes. Returns `None` if there were any/// failures when starting, stopping, or communicating with the subprocess.fn run_tool(    ui: &Ui,    workspace_root: &Path,    path_converter: &RepoPathUiConverter,    tool_command: &CommandNameAndArgs,    file_to_fix: &FileToFix,    old_content: &[u8],) -> Result<Vec<u8>, ()> {    let mut vars: HashMap<&str, &str> = HashMap::new();    vars.insert("path", file_to_fix.repo_path.as_internal_file_string());    // TODO: workspace_root.to_str() returns None if the workspace path is not    // UTF-8, but we ignore that failure so `jj fix` still runs in that    // situation. Maybe we should do something like substituting bytes instead    // of strings so we can handle any Path here.    if let Some(root) = workspace_root.to_str() {        vars.insert("root", root);    }    let mut command = tool_command.to_command_with_variables(&vars);    tracing::debug!(?command, ?file_to_fix.repo_path, "spawning fix tool");    let Ok(mut child) = command        .current_dir(workspace_root)        .stdin(Stdio::piped())        .stdout(Stdio::piped())        .stderr(Stdio::piped())        .spawn()    else {        writeln!(            ui.warning_default(),            "Failed to start `{}`",            tool_command.split_name(),        )        .ok();        return Err(());    };    let mut stdin = child.stdin.take().expect(        "The child process is created with piped stdin, and it's our first access to stdin.",    );    let output = std::thread::scope(|s| {        s.spawn(move || {            stdin.write_all(old_content).ok();        });        child.wait_with_output().or(Err(()))    })?;    tracing::debug!(?command, ?output.status, "fix tool exited:");    if !output.stderr.is_empty() {        let mut stderr = ui.stderr();        writeln!(            stderr,            "{}:",            path_converter.format_file_path(&file_to_fix.repo_path)        )        .ok();        stderr.write_all(&output.stderr).ok();        writeln!(stderr).ok();    }    if output.status.success() {        Ok(output.stdout)    } else {        writeln!(            ui.warning_default(),            "Fix tool `{}` exited with non-zero exit code for `{}`",            tool_command.split_name(),            path_converter.format_file_path(&file_to_fix.repo_path)        )        .ok();        Err(())    }} /// Represents an entry in the `fix.tools` config table.struct ToolConfig {    /// The command that will be run to fix a matching file.    command: CommandNameAndArgs,    /// The matcher that determines if this tool matches a file.    matcher: Box<dyn Matcher>,    /// Whether the tool is enabled    enabled: bool,    // TODO: Store the `name` field here and print it with the command's stderr, to clearly    // associate any errors/warnings with the tool and its configuration entry.} /// Represents the `fix.tools` config table.struct ToolsConfig {    /// Some tools, stored in the order they will be executed if more than one    /// of them matches the same file.    tools: Vec<ToolConfig>,} /// Simplifies deserialization of the config values while building a ToolConfig.#[derive(Clone, Debug, Eq, PartialEq, serde::Deserialize)]#[serde(rename_all = "kebab-case")]struct RawToolConfig {    command: CommandNameAndArgs,    patterns: Vec<String>,    #[serde(default = "default_tool_enabled")]    enabled: bool,} fn default_tool_enabled() -> bool {    true} /// Parses the `fix.tools` config table.////// Fails if any of the commands or patterns are obviously unusable, but does/// not check for issues that might still occur later like missing executables./// This is a place where we could fail earlier in some cases, though.fn get_tools_config(    ui: &mut Ui,    settings: &UserSettings,    fileset_context: &FilesetParseContext,) -> Result<ToolsConfig, CommandError> {    let mut tools: Vec<ToolConfig> = settings        .table_keys("fix.tools")        // Sort keys early so errors are deterministic.        .sorted()        .map(|name| -> Result<ToolConfig, CommandError> {            let mut diagnostics = FilesetDiagnostics::new();            let tool: RawToolConfig = settings.get(["fix", "tools", name])?;            let expression = FilesetExpression::union_all(                tool.patterns                    .iter()                    .map(|arg| fileset::parse(&mut diagnostics, arg, fileset_context))                    .try_collect()?,            );            print_parse_diagnostics(ui, &format!("In `fix.tools.{name}`"), &diagnostics)?;            Ok(ToolConfig {                command: tool.command,                matcher: expression.to_matcher(),                enabled: tool.enabled,            })        })        .try_collect()?;    if tools.is_empty() {        return Err(config_error("No `fix.tools` are configured"));    }    tools.retain(|t| t.enabled);    if tools.is_empty() {        Err(config_error(            "At least one entry of `fix.tools` must be enabled.".to_string(),        ))    } else {        Ok(ToolsConfig { tools })    }}