1 //! Runs rustfmt on the repository.
3 use crate::builder::Builder;
4 use crate::util::{output, t};
5 use ignore::WalkBuilder;
6 use std::collections::VecDeque;
7 use std::path::{Path, PathBuf};
8 use std::process::{Command, Stdio};
9 use std::sync::mpsc::SyncSender;
11 fn rustfmt(src: &Path, rustfmt: &Path, paths: &[PathBuf], check: bool) -> impl FnMut(bool) -> bool {
12 let mut cmd = Command::new(&rustfmt);
13 // avoid the submodule config paths from coming into play,
14 // we only allow a single global config for the workspace for now
15 cmd.arg("--config-path").arg(&src.canonicalize().unwrap());
16 cmd.arg("--edition").arg("2021");
17 cmd.arg("--unstable-features");
18 cmd.arg("--skip-children");
23 let cmd_debug = format!("{:?}", cmd);
24 let mut cmd = cmd.spawn().expect("running rustfmt");
25 // poor man's async: return a closure that'll wait for rustfmt's completion
26 move |block: bool| -> bool {
28 match cmd.try_wait() {
33 let status = cmd.wait().unwrap();
34 if !status.success() {
36 "Running `{}` failed.\nIf you're running `tidy`, \
37 try again with `--bless`. Or, if you just want to format \
38 code, run `./x.py fmt` instead.",
41 crate::detail_exit(1);
47 #[derive(serde::Deserialize)]
48 struct RustfmtConfig {
52 pub fn format(build: &Builder<'_>, check: bool, paths: &[PathBuf]) {
53 if build.config.dry_run() {
56 let mut builder = ignore::types::TypesBuilder::new();
57 builder.add_defaults();
58 builder.select("rust");
59 let matcher = builder.build().unwrap();
60 let rustfmt_config = build.src.join("rustfmt.toml");
61 if !rustfmt_config.exists() {
62 eprintln!("Not running formatting checks; rustfmt.toml does not exist.");
63 eprintln!("This may happen in distributed tarballs.");
66 let rustfmt_config = t!(std::fs::read_to_string(&rustfmt_config));
67 let rustfmt_config: RustfmtConfig = t!(toml::from_str(&rustfmt_config));
68 let mut ignore_fmt = ignore::overrides::OverrideBuilder::new(&build.src);
69 for ignore in rustfmt_config.ignore {
70 ignore_fmt.add(&format!("!{}", ignore)).expect(&ignore);
72 let git_available = match Command::new("git")
74 .stdout(Stdio::null())
75 .stderr(Stdio::null())
78 Ok(status) => status.success(),
82 let in_working_tree = match build
86 .arg("--is-inside-work-tree")
87 .stdout(Stdio::null())
88 .stderr(Stdio::null())
91 Ok(status) => status.success(),
95 let untracked_paths_output = output(
96 build.config.git().arg("status").arg("--porcelain").arg("--untracked-files=normal"),
98 let untracked_paths = untracked_paths_output
100 .filter(|entry| entry.starts_with("??"))
102 entry.split(' ').nth(1).expect("every git status entry should list a path")
104 for untracked_path in untracked_paths {
105 println!("skip untracked path {} during rustfmt invocations", untracked_path);
106 // The leading `/` makes it an exact match against the
107 // repository root, rather than a glob. Without that, if you
108 // have `foo.rs` in the repository root it will also match
109 // against anything like `compiler/rustc_foo/src/foo.rs`,
110 // preventing the latter from being formatted.
111 ignore_fmt.add(&format!("!/{}", untracked_path)).expect(&untracked_path);
114 println!("Not in git tree. Skipping git-aware format checks");
117 println!("Could not find usable git. Skipping git-aware format checks");
119 let ignore_fmt = ignore_fmt.build().unwrap();
121 let rustfmt_path = build.initial_rustfmt().unwrap_or_else(|| {
122 eprintln!("./x.py fmt is not supported on this channel");
123 crate::detail_exit(1);
125 assert!(rustfmt_path.exists(), "{}", rustfmt_path.display());
126 let src = build.src.clone();
127 let (tx, rx): (SyncSender<PathBuf>, _) = std::sync::mpsc::sync_channel(128);
128 let walker = match paths.get(0) {
130 let mut walker = WalkBuilder::new(first);
131 for path in &paths[1..] {
136 None => WalkBuilder::new(src.clone()),
139 .overrides(ignore_fmt)
142 // there is a lot of blocking involved in spawning a child process and reading files to format.
143 // spawn more processes than available concurrency to keep the CPU busy
144 let max_processes = build.jobs() as usize * 2;
146 // spawn child processes on a separate thread so we can batch entries we have received from ignore
147 let thread = std::thread::spawn(move || {
148 let mut children = VecDeque::new();
149 while let Ok(path) = rx.recv() {
150 // try getting a few more paths from the channel to amortize the overhead of spawning processes
151 let paths: Vec<_> = rx.try_iter().take(7).chain(std::iter::once(path)).collect();
153 let child = rustfmt(&src, &rustfmt_path, paths.as_slice(), check);
154 children.push_back(child);
156 // poll completion before waiting
157 for i in (0..children.len()).rev() {
158 if children[i](false) {
159 children.swap_remove_back(i);
164 if children.len() >= max_processes {
165 // await oldest child
166 children.pop_front().unwrap()(true);
170 // await remaining children
171 for mut child in children {
178 Box::new(move |entry| {
179 let entry = t!(entry);
180 if entry.file_type().map_or(false, |t| t.is_file()) {
181 t!(tx.send(entry.into_path()));
183 ignore::WalkState::Continue
189 thread.join().unwrap();