Implement ./x.py fmt [--check].

src/bootstrap/builder.rs

@@ -314,6 +314,7 @@ pub enum Kind {
  Check,
  Clippy,
  Fix,
+ Format,
  Test,
  Bench,
  Dist,
@@ -353,7 +354,7 @@ impl<'a> Builder<'a> {
  tool::Miri,
  native::Lld
  ),
- Kind::Check | Kind::Clippy | Kind::Fix => describe!(
+ Kind::Check | Kind::Clippy | Kind::Fix | Kind::Format => describe!(
  check::Std,
  check::Rustc,
  check::Rustdoc
@@ -514,7 +515,7 @@ impl<'a> Builder<'a> {
  Subcommand::Bench { ref paths, .. } => (Kind::Bench, &paths[..]),
  Subcommand::Dist { ref paths } => (Kind::Dist, &paths[..]),
  Subcommand::Install { ref paths } => (Kind::Install, &paths[..]),
- Subcommand::Clean { .. } => panic!(),
+ Subcommand::Format { .. } | Subcommand::Clean { .. } => panic!(),
  };
 
  let builder = Builder {

src/bootstrap/config.rs

@@ -5,6 +5,7 @@
 
 use std::collections::{HashMap, HashSet};
 use std::env;
+use std::ffi::OsString;
 use std::fs;
 use std::path::{Path, PathBuf};
 use std::process;
@@ -149,6 +150,7 @@ pub struct Config {
  // These are either the stage0 downloaded binaries or the locally installed ones.
  pub initial_cargo: PathBuf,
  pub initial_rustc: PathBuf,
+ pub initial_rustfmt: Option<PathBuf>,
  pub out: PathBuf,
 }
 
@@ -348,12 +350,16 @@ struct TomlTarget {
 impl Config {
  fn path_from_python(var_key: &str) -> PathBuf {
  match env::var_os(var_key) {
- // Do not trust paths from Python and normalize them slightly (#49785).
- Some(var_val) => Path::new(&var_val).components().collect(),
+ Some(var_val) => Self::normalize_python_path(var_val),
  _ => panic!("expected '{}' to be set", var_key),
  }
  }
 
+ /// Normalizes paths from Python slightly. We don't trust paths from Python (#49785).
+ fn normalize_python_path(path: OsString) -> PathBuf {
+ Path::new(&path).components().collect()
+ }
+
  pub fn default_opts() -> Config {
  let mut config = Config::default();
  config.llvm_optimize = true;
@@ -380,6 +386,7 @@ impl Config {
 
  config.initial_rustc = Config::path_from_python("RUSTC");
  config.initial_cargo = Config::path_from_python("CARGO");
+ config.initial_rustfmt = env::var_os("RUSTFMT").map(Config::normalize_python_path);
 
  config
  }

src/bootstrap/flags.rs

@@ -53,6 +53,9 @@ pub enum Subcommand {
  Fix {
  paths: Vec<PathBuf>,
  },
+ Format {
+ check: bool,
+ },
  Doc {
  paths: Vec<PathBuf>,
  },
@@ -102,6 +105,7 @@ Subcommands:
  check Compile either the compiler or libraries, using cargo check
  clippy Run clippy
  fix Run cargo fix
+ fmt Run rustfmt
  test Build and run some test suites
  bench Build and run some benchmarks
  doc Build documentation
@@ -160,6 +164,7 @@ To learn more about a subcommand, run `./x.py <subcommand> -h`"
  || (s == "check")
  || (s == "clippy")
  || (s == "fix")
+ || (s == "fmt")
  || (s == "test")
  || (s == "bench")
  || (s == "doc")
@@ -222,6 +227,9 @@ To learn more about a subcommand, run `./x.py <subcommand> -h`"
  "clean" => {
  opts.optflag("", "all", "clean all build artifacts");
  }
+ "fmt" => {
+ opts.optflag("", "check", "check formatting instead of applying.");
+ }
  _ => {}
  };
 
@@ -323,6 +331,17 @@ Arguments:
  ./x.py fix src/libcore src/libproc_macro",
  );
  }
+ "fmt" => {
+ subcommand_help.push_str(
+ "\n
+Arguments:
+ This subcommand optionally accepts a `--check` flag which succeeds if formatting is correct and
+ fails if it is not. For example:
+
+ ./x.py fmt
+ ./x.py fmt --check",
+ );
+ }
  "test" => {
  subcommand_help.push_str(
  "\n
@@ -388,7 +407,7 @@ Arguments:
 
  let maybe_rules_help = Builder::get_help(&build, subcommand.as_str());
  extra_help.push_str(maybe_rules_help.unwrap_or_default().as_str());
- } else if subcommand.as_str() != "clean" {
+ } else if !(subcommand.as_str() == "clean" || subcommand.as_str() == "fmt") {
  extra_help.push_str(
  format!(
  "Run `./x.py {} -h -v` to see a list of available paths.",
@@ -439,6 +458,11 @@ Arguments:
  all: matches.opt_present("all"),
  }
  }
+ "fmt" => {
+ Subcommand::Format {
+ check: matches.opt_present("check"),
+ }
+ }
  "dist" => Subcommand::Dist { paths },
  "install" => Subcommand::Install { paths },
  _ => {

src/bootstrap/format.rs

@@ -0,0 +1,28 @@
+//! Runs rustfmt on the repository.
+
+use crate::{util, Build};
+use std::process::Command;
+
+pub fn format(build: &Build, check: bool) {
+ let target = &build.build;
+ let rustfmt_path = build.config.initial_rustfmt.as_ref().unwrap_or_else(|| {
+ eprintln!("./x.py fmt is not supported on this channel");
+ std::process::exit(1);
+ }).clone();
+ let cargo_fmt_path = rustfmt_path.with_file_name(util::exe("cargo-fmt", &target));
+ assert!(cargo_fmt_path.is_file(), "{} not a file", cargo_fmt_path.display());
+
+ let mut cmd = Command::new(&cargo_fmt_path);
+ // cargo-fmt calls rustfmt as a bare command, so we need it to only find the correct one
+ cmd.env("PATH", cargo_fmt_path.parent().unwrap());
+ cmd.current_dir(&build.src);
+ cmd.arg("fmt");
+
+ if check {
+ cmd.arg("--");
+ cmd.arg("--check");
+ }
+
+ let status = cmd.status().expect("executing cargo-fmt");
+ assert!(status.success(), "cargo-fmt errored with status {:?}", status);
+}

src/bootstrap/lib.rs

@@ -147,6 +147,7 @@ mod builder;
 mod cache;
 mod tool;
 mod toolstate;
+mod format;
 
 #[cfg(windows)]
 mod job;
@@ -421,6 +422,10 @@ impl Build {
  job::setup(self);
  }
 
+ if let Subcommand::Format { check } = self.config.cmd {
+ return format::format(self, check);
+ }
+
  if let Subcommand::Clean { all } = self.config.cmd {
  return clean::clean(self, all);
  }