1 files changed, 194 insertions, 0 deletions
diff --git a/src/tools/clippy/src/main.rs b/src/tools/clippy/src/main.rs
new file mode 100644
index 000000000..9ee4a40cb
--- /dev/null
+++ b/src/tools/clippy/src/main.rs
@@ -0,0 +1,194 @@
+#![cfg_attr(feature = "deny-warnings", deny(warnings))]
+// warn on lints, that are included in `rust-lang/rust`s bootstrap
+#![warn(rust_2018_idioms, unused_lifetimes)]
+
+use rustc_tools_util::VersionInfo;
+use std::env;
+use std::path::PathBuf;
+use std::process::{self, Command};
+
+const CARGO_CLIPPY_HELP: &str = r#"Checks a package to catch common mistakes and improve your Rust code.
+
+Usage:
+    cargo clippy [options] [--] [<opts>...]
+
+Common options:
+    --no-deps                Run Clippy only on the given crate, without linting the dependencies
+    --fix                    Automatically apply lint suggestions. This flag implies `--no-deps`
+    -h, --help               Print this message
+    -V, --version            Print version info and exit
+
+Other options are the same as `cargo check`.
+
+To allow or deny a lint from the command line you can use `cargo clippy --`
+with:
+
+    -W --warn OPT       Set lint warnings
+    -A --allow OPT      Set lint allowed
+    -D --deny OPT       Set lint denied
+    -F --forbid OPT     Set lint forbidden
+
+You can use tool lints to allow or deny lints from your code, eg.:
+
+    #[allow(clippy::needless_lifetimes)]
+"#;
+
+fn show_help() {
+    println!("{}", CARGO_CLIPPY_HELP);
+}
+
+fn show_version() {
+    let version_info = rustc_tools_util::get_version_info!();
+    println!("{}", version_info);
+}
+
+pub fn main() {
+    // Check for version and help flags even when invoked as 'cargo-clippy'
+    if env::args().any(|a| a == "--help" || a == "-h") {
+        show_help();
+        return;
+    }
+
+    if env::args().any(|a| a == "--version" || a == "-V") {
+        show_version();
+        return;
+    }
+
+    if let Err(code) = process(env::args().skip(2)) {
+        process::exit(code);
+    }
+}
+
+struct ClippyCmd {
+    cargo_subcommand: &'static str,
+    args: Vec<String>,
+    clippy_args: Vec<String>,
+}
+
+impl ClippyCmd {
+    fn new<I>(mut old_args: I) -> Self
+    where
+        I: Iterator<Item = String>,
+    {
+        let mut cargo_subcommand = "check";
+        let mut args = vec![];
+        let mut clippy_args: Vec<String> = vec![];
+
+        for arg in old_args.by_ref() {
+            match arg.as_str() {
+                "--fix" => {
+                    cargo_subcommand = "fix";
+                    continue;
+                },
+                "--no-deps" => {
+                    clippy_args.push("--no-deps".into());
+                    continue;
+                },
+                "--" => break,
+                _ => {},
+            }
+
+            args.push(arg);
+        }
+
+        clippy_args.append(&mut (old_args.collect()));
+        if cargo_subcommand == "fix" && !clippy_args.iter().any(|arg| arg == "--no-deps") {
+            clippy_args.push("--no-deps".into());
+        }
+
+        Self {
+            cargo_subcommand,
+            args,
+            clippy_args,
+        }
+    }
+
+    fn path() -> PathBuf {
+        let mut path = env::current_exe()
+            .expect("current executable path invalid")
+            .with_file_name("clippy-driver");
+
+        if cfg!(windows) {
+            path.set_extension("exe");
+        }
+
+        path
+    }
+
+    fn into_std_cmd(self) -> Command {
+        let mut cmd = Command::new("cargo");
+        let clippy_args: String = self
+            .clippy_args
+            .iter()
+            .map(|arg| format!("{}__CLIPPY_HACKERY__", arg))
+            .collect();
+
+        // Currently, `CLIPPY_TERMINAL_WIDTH` is used only to format "unknown field" error messages.
+        let terminal_width = termize::dimensions().map_or(0, |(w, _)| w);
+
+        cmd.env("RUSTC_WORKSPACE_WRAPPER", Self::path())
+            .env("CLIPPY_ARGS", clippy_args)
+            .env("CLIPPY_TERMINAL_WIDTH", terminal_width.to_string())
+            .arg(self.cargo_subcommand)
+            .args(&self.args);
+
+        cmd
+    }
+}
+
+fn process<I>(old_args: I) -> Result<(), i32>
+where
+    I: Iterator<Item = String>,
+{
+    let cmd = ClippyCmd::new(old_args);
+
+    let mut cmd = cmd.into_std_cmd();
+
+    let exit_status = cmd
+        .spawn()
+        .expect("could not run cargo")
+        .wait()
+        .expect("failed to wait for cargo?");
+
+    if exit_status.success() {
+        Ok(())
+    } else {
+        Err(exit_status.code().unwrap_or(-1))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::ClippyCmd;
+
+    #[test]
+    fn fix() {
+        let args = "cargo clippy --fix".split_whitespace().map(ToString::to_string);
+        let cmd = ClippyCmd::new(args);
+        assert_eq!("fix", cmd.cargo_subcommand);
+        assert!(!cmd.args.iter().any(|arg| arg.ends_with("unstable-options")));
+    }
+
+    #[test]
+    fn fix_implies_no_deps() {
+        let args = "cargo clippy --fix".split_whitespace().map(ToString::to_string);
+        let cmd = ClippyCmd::new(args);
+        assert!(cmd.clippy_args.iter().any(|arg| arg == "--no-deps"));
+    }
+
+    #[test]
+    fn no_deps_not_duplicated_with_fix() {
+        let args = "cargo clippy --fix -- --no-deps"
+            .split_whitespace()
+            .map(ToString::to_string);
+        let cmd = ClippyCmd::new(args);
+        assert_eq!(cmd.clippy_args.iter().filter(|arg| *arg == "--no-deps").count(), 1);
+    }
+
+    #[test]
+    fn check() {
+        let args = "cargo clippy".split_whitespace().map(ToString::to_string);
+        let cmd = ClippyCmd::new(args);
+        assert_eq!("check", cmd.cargo_subcommand);
+    }
+}