Add cargo marker install rustc-driver

Author: xFrednet

cargo-marker/src/driver.rs

@@ -0,0 +1,89 @@
+//! This module hosts functions required to run rustc as a driver.
+//!
+//! The rustc driver depends on rustc, which interfaces is unstable. This means
+//! that each driver version is bound to a specific version of rustc. The same
+//! goes for Clippy. However, Clippy has the advantage, that it's distributes via
+//! rustup, which handles the version matching for it. We're not so lucky, at
+//! least not yet. Therefore, we're responsible that the driver is compiled and
+//! run with the correct toolchain.
+//!
+//! If no driver is installed, the user will be requested to run the setup command.
+//! That command will first ensure that the required toolchain is installed and then
+//! run `cargo install` for the driver with a specific toolchain. The version and
+//! toolchain are hardcoded in this crate.
+//!
+//! If a driver is already installed. We'll first run the driver to request the
+//! required toolchain and then run the driver using that toolchain. Requesting
+//! the toolchain works, since the argument will be processed before rustc is run.
+//! At least, that's the idea.
+
+use std::process::Command;
+
+use once_cell::sync::Lazy;
+
+use crate::ExitStatus;
+
+/// This is the driver version and toolchain, that is used by the setup command
+/// to install the driver.
+static DEFAULT_DRIVER_INFO: Lazy<RustcDriverInfo> = Lazy::new(|| RustcDriverInfo {
+    toolchain: "nightly-2022-11-03".to_string(),
+    version: "0.1.0".to_string(),
+});
+
+struct RustcDriverInfo {
+    toolchain: String,
+    version: String,
+}
+
+/// This function checks if the specified toolchain is installed. This requires
+/// rustup. A dependency we have to live with for now.
+fn check_toolchain(toolchain: &str) -> Result<(), ExitStatus> {
+    let mut cmd = Command::new("cargo");
+    cmd.args([&format!("+{toolchain}"), "-V"]);
+    if cmd.output().is_err() {
+        eprintln!("error: the required toolchain `{toolchain}` can't be found");
+        eprintln!();
+        eprintln!("You can install the toolchain by running: rustup toolchain install {toolchain}");
+        Err(ExitStatus::InvalidToolchain)
+    } else {
+        Ok(())
+    }
+}
+
+/// This tries to install the rustc driver specified in [`DEFAULT_DRIVER_INFO`].
+pub fn install_driver(verbose: bool) -> Result<(), ExitStatus> {
+    // Prerequisites
+    let toolchain = &DEFAULT_DRIVER_INFO.toolchain;
+    check_toolchain(&toolchain)?;
+
+    // Build driver
+    let mut cmd = Command::new("cargo");
+    cmd.arg(&format!("+{toolchain}"));
+
+    if verbose {
+        cmd.arg("--verbose");
+    }
+
+    #[cfg(feature = "dev-build")]
+    cmd.args(["build", "--bin", "linter_driver_rustc"]);
+    #[cfg(not(feature = "dev-build"))]
+    cmd.args([
+        "install",
+        "marker_rustc_driver",
+        "--version",
+        &DEFAULT_DRIVER_INFO.version,
+    ]);
+
+    let status = cmd
+        .spawn()
+        .expect("unable to start cargo install for the driver")
+        .wait()
+        .expect("unable to wait on cargo install for the driver");
+    if status.success() {
+        Ok(())
+    } else {
+        // The user can see cargo's output, as the command output was passed on
+        // to the user via the `.spawn()` call.
+        Err(ExitStatus::DriverInstallationFailed)
+    }
+}

cargo-marker/src/main.rs

@@ -9,13 +9,32 @@ use std::{
 };
 
 use clap::{self, Arg, ArgAction};
-use once_cell::sync::Lazy;
+use once_cell::sync::{Lazy, OnceCell};
+
+mod driver;
 
 const CARGO_ARGS_SEPARATOR: &str = "--";
 const VERSION: &str = concat!("cargo-marker ", env!("CARGO_PKG_VERSION"));
 const LINT_KRATES_BASE_DIR: &str = "./target/marker";
 static LINT_KRATES_TARGET_DIR: Lazy<String> = Lazy::new(|| prepare_lint_build_dir("build", "target"));
 static LINT_KRATES_OUT_DIR: Lazy<String> = Lazy::new(|| prepare_lint_build_dir("lints", "out"));
+static VERBOSE: OnceCell<bool> = OnceCell::new();
+
+#[derive(Debug)]
+pub enum ExitStatus {
+    /// The toolchain validation failed. This could happen, if rustup is not
+    /// installed or the required toolchain is not installed.
+    InvalidToolchain = 100,
+    DriverInstallationFailed = 200,
+}
+
+fn set_verbose(verbose: bool) {
+    VERBOSE.set(verbose).unwrap();
+}
+
+fn is_verbose() -> bool {
+    VERBOSE.get().copied().unwrap_or_default()
+}
 
 /// This creates the absolute path for a given build directory.
 fn prepare_lint_build_dir(dir_name: &str, info_name: &str) -> String {
@@ -38,18 +57,23 @@ fn prepare_lint_build_dir(dir_name: &str, info_name: &str) -> String {
         .to_string()
 }
 
-fn main() {
+fn main() -> Result<(), ExitStatus> {
     let matches = get_clap_config().get_matches_from(
         std::env::args()
             .enumerate()
             .filter_map(|(index, value)| (!(index == 1 && value == "marker")).then_some(value))
             .take_while(|s| s != CARGO_ARGS_SEPARATOR),
     );
 
+    set_verbose(matches.get_flag("verbose"));
+
     if matches.get_flag("version") {
-        let version_info = env!("CARGO_PKG_VERSION");
-        println!("cargo-marker version: {version_info}");
-        exit(0);
+        print_version();
+        return Ok(());
+    }
+
+    if !validate_toolchain() {
+        return Err(ExitStatus::InvalidToolchain);
     }
 
     let verbose = matches.get_flag("verbose");
@@ -87,6 +111,15 @@ fn main() {
     }
 }
 
+fn print_version() {
+    println!("cargo-marker version: {}", env!("CARGO_PKG_VERSION"));
+
+    if is_verbose() {
+        println!("driver toolchain: {DRIVER_TOOLCHAIN}")
+    }
+}
+
+
 fn run_driver(driver_path: &PathBuf, lint_crates: &str) {
     println!();
     println!("Start linting:");

util/update-toolchain.sh

@@ -2,7 +2,7 @@
 
 if [[ $1 == nightly-????-??-?? ]]
 then
-    sed -i "s/nightly-2022-11-03/$1/g" ./marker_driver_rustc/src/main.rs ./rust-toolchain .github/workflows/* ./util/update-toolchain.sh
+    sed -i "s/nightly-2022-11-03/$1/g" ./marker_driver_rustc/src/main.rs ./rust-toolchain .github/workflows/* ./util/update-toolchain.sh cargo-marker/src/main.rs
 else
     echo "Please enter a valid toolchain like \`nightly-2022-01-01\`"
 fi;