1 //! Runs rustfmt on the repository.
3 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() {
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
27 let status = cmd.wait().unwrap();
28 if !status.success() {
30 "Running `{}` failed.\nIf you're running `tidy`, \
31 try again with `--bless`. Or, if you just want to format \
32 code, run `./x.py fmt` instead.",
35 std::process::exit(1);
40 #[derive(serde::Deserialize)]
41 struct RustfmtConfig {
45 pub fn format(build: &Build, check: bool, paths: &[PathBuf]) {
46 if build.config.dry_run {
49 let mut builder = ignore::types::TypesBuilder::new();
50 builder.add_defaults();
51 builder.select("rust");
52 let matcher = builder.build().unwrap();
53 let rustfmt_config = build.src.join("rustfmt.toml");
54 if !rustfmt_config.exists() {
55 eprintln!("Not running formatting checks; rustfmt.toml does not exist.");
56 eprintln!("This may happen in distributed tarballs.");
59 let rustfmt_config = t!(std::fs::read_to_string(&rustfmt_config));
60 let rustfmt_config: RustfmtConfig = t!(toml::from_str(&rustfmt_config));
61 let mut ignore_fmt = ignore::overrides::OverrideBuilder::new(&build.src);
62 for ignore in rustfmt_config.ignore {
63 ignore_fmt.add(&format!("!{}", ignore)).expect(&ignore);
65 let git_available = match Command::new("git")
67 .stdout(Stdio::null())
68 .stderr(Stdio::null())
71 Ok(status) => status.success(),
75 let in_working_tree = match Command::new("git")
77 .arg("--is-inside-work-tree")
78 .stdout(Stdio::null())
79 .stderr(Stdio::null())
82 Ok(status) => status.success(),
86 let untracked_paths_output = output(
90 .arg("--untracked-files=normal"),
92 let untracked_paths = untracked_paths_output
94 .filter(|entry| entry.starts_with("??"))
96 entry.split(' ').nth(1).expect("every git status entry should list a path")
98 for untracked_path in untracked_paths {
99 eprintln!("skip untracked path {} during rustfmt invocations", untracked_path);
100 // The leading `/` makes it an exact match against the
101 // repository root, rather than a glob. Without that, if you
102 // have `foo.rs` in the repository root it will also match
103 // against anything like `compiler/rustc_foo/src/foo.rs`,
104 // preventing the latter from being formatted.
105 ignore_fmt.add(&format!("!/{}", untracked_path)).expect(&untracked_path);
108 eprintln!("Not in git tree. Skipping git-aware format checks");
111 eprintln!("Could not find usable git. Skipping git-aware format checks");
113 let ignore_fmt = ignore_fmt.build().unwrap();
115 let rustfmt_path = build
120 eprintln!("./x.py fmt is not supported on this channel");
121 std::process::exit(1);
124 let src = build.src.clone();
125 let (tx, rx): (SyncSender<PathBuf>, _) = std::sync::mpsc::sync_channel(128);
126 let walker = match paths.get(0) {
128 let mut walker = WalkBuilder::new(first);
129 for path in &paths[1..] {
134 None => WalkBuilder::new(src.clone()),
137 .overrides(ignore_fmt)
140 // there is a lot of blocking involved in spawning a child process and reading files to format.
141 // spawn more processes than available concurrency to keep the CPU busy
142 let max_processes = build.jobs() as usize * 2;
144 // spawn child processes on a separate thread so we can batch entries we have received from ignore
145 let thread = std::thread::spawn(move || {
146 let mut children = VecDeque::new();
147 while let Ok(path) = rx.recv() {
148 // try getting a few more paths from the channel to amortize the overhead of spawning processes
149 let paths: Vec<_> = rx.try_iter().take(7).chain(std::iter::once(path)).collect();
151 let child = rustfmt(&src, &rustfmt_path, paths.as_slice(), check);
152 children.push_back(child);
154 if children.len() >= max_processes {
155 // await oldest child
156 children.pop_front().unwrap()();
160 // await remaining children
161 for mut child in children {
168 Box::new(move |entry| {
169 let entry = t!(entry);
170 if entry.file_type().map_or(false, |t| t.is_file()) {
171 t!(tx.send(entry.into_path()));
173 ignore::WalkState::Continue
179 thread.join().unwrap();