src/driver.rs

   1 #![feature(rustc_private)]
   2
   3 // FIXME: switch to something more ergonomic here, once available.
   4 // (Currently there is no way to opt into sysroot crates without `extern crate`.)
   5 #[allow(unused_extern_crates)]
   6 extern crate rustc_driver;
   7 #[allow(unused_extern_crates)]
   8 extern crate rustc_interface;
   9 #[allow(unused_extern_crates)]
  10 extern crate rustc_plugin;
  11
  12 use rustc_interface::interface;
  13 use rustc_tools_util::*;
  14
  15 use std::path::Path;
  16 use std::process::{exit, Command};
  17
  18 /// If a command-line option matches `find_arg`, then apply the predicate `pred` on its value. If
  19 /// true, then return it. The parameter is assumed to be either `--arg=value` or `--arg value`.
  20 fn arg_value<'a>(
  21     args: impl IntoIterator<Item = &'a String>,
  22     find_arg: &str,
  23     pred: impl Fn(&str) -> bool,
  24 ) -> Option<&'a str> {
  25     let mut args = args.into_iter().map(String::as_str);
  26
  27     while let Some(arg) = args.next() {
  28         let arg: Vec<_> = arg.splitn(2, '=').collect();
  29         if arg.get(0) != Some(&find_arg) {
  30             continue;
  31         }
  32
  33         let value = arg.get(1).cloned().or_else(|| args.next());
  34         if value.as_ref().map_or(false, |p| pred(p)) {
  35             return value;
  36         }
  37     }
  38     None
  39 }
  40
  41 #[test]
  42 fn test_arg_value() {
  43     let args: Vec<_> = ["--bar=bar", "--foobar", "123", "--foo"]
  44         .iter()
  45         .map(std::string::ToString::to_string)
  46         .collect();
  47
  48     assert_eq!(arg_value(None, "--foobar", |_| true), None);
  49     assert_eq!(arg_value(&args, "--bar", |_| false), None);
  50     assert_eq!(arg_value(&args, "--bar", |_| true), Some("bar"));
  51     assert_eq!(arg_value(&args, "--bar", |p| p == "bar"), Some("bar"));
  52     assert_eq!(arg_value(&args, "--bar", |p| p == "foo"), None);
  53     assert_eq!(arg_value(&args, "--foobar", |p| p == "foo"), None);
  54     assert_eq!(arg_value(&args, "--foobar", |p| p == "123"), Some("123"));
  55     assert_eq!(arg_value(&args, "--foo", |_| true), None);
  56 }
  57
  58 #[allow(clippy::too_many_lines)]
  59
  60 struct ClippyCallbacks;
  61
  62 impl rustc_driver::Callbacks for ClippyCallbacks {
  63     fn after_parsing(&mut self, compiler: &interface::Compiler) -> bool {
  64         let sess = compiler.session();
  65         let mut registry = rustc_plugin::registry::Registry::new(
  66             sess,
  67             compiler
  68                 .parse()
  69                 .expect(
  70                     "at this compilation stage \
  71                      the crate must be parsed",
  72                 )
  73                 .peek()
  74                 .span,
  75         );
  76         registry.args_hidden = Some(Vec::new());
  77
  78         let conf = clippy_lints::read_conf(&registry);
  79         clippy_lints::register_plugins(&mut registry, &conf);
  80
  81         let rustc_plugin::registry::Registry {
  82             early_lint_passes,
  83             late_lint_passes,
  84             lint_groups,
  85             llvm_passes,
  86             attributes,
  87             ..
  88         } = registry;
  89         let mut ls = sess.lint_store.borrow_mut();
  90         for pass in early_lint_passes {
  91             ls.register_early_pass(Some(sess), true, false, pass);
  92         }
  93         for pass in late_lint_passes {
  94             ls.register_late_pass(Some(sess), true, false, false, pass);
  95         }
  96
  97         for (name, (to, deprecated_name)) in lint_groups {
  98             ls.register_group(Some(sess), true, name, deprecated_name, to);
  99         }
 100         clippy_lints::register_pre_expansion_lints(sess, &mut ls, &conf);
 101         clippy_lints::register_renamed(&mut ls);
 102
 103         sess.plugin_llvm_passes.borrow_mut().extend(llvm_passes);
 104         sess.plugin_attributes.borrow_mut().extend(attributes);
 105
 106         // Continue execution
 107         true
 108     }
 109 }
 110
 111 pub fn main() {
 112     rustc_driver::init_rustc_env_logger();
 113     exit(
 114         rustc_driver::report_ices_to_stderr_if_any(move || {
 115             use std::env;
 116
 117             if std::env::args().any(|a| a == "--version" || a == "-V") {
 118                 let version_info = rustc_tools_util::get_version_info!();
 119                 println!("{}", version_info);
 120                 exit(0);
 121             }
 122
 123             let mut orig_args: Vec<String> = env::args().collect();
 124
 125             // Get the sysroot, looking from most specific to this invocation to the least:
 126             // - command line
 127             // - runtime environment
 128             //    - SYSROOT
 129             //    - RUSTUP_HOME, MULTIRUST_HOME, RUSTUP_TOOLCHAIN, MULTIRUST_TOOLCHAIN
 130             // - sysroot from rustc in the path
 131             // - compile-time environment
 132             let sys_root_arg = arg_value(&orig_args, "--sysroot", |_| true);
 133             let have_sys_root_arg = sys_root_arg.is_some();
 134             let sys_root = sys_root_arg
 135                 .map(std::string::ToString::to_string)
 136                 .or_else(|| std::env::var("SYSROOT").ok())
 137                 .or_else(|| {
 138                     let home = option_env!("RUSTUP_HOME").or(option_env!("MULTIRUST_HOME"));
 139                     let toolchain = option_env!("RUSTUP_TOOLCHAIN").or(option_env!("MULTIRUST_TOOLCHAIN"));
 140                     home.and_then(|home| toolchain.map(|toolchain| format!("{}/toolchains/{}", home, toolchain)))
 141                 })
 142                 .or_else(|| {
 143                     Command::new("rustc")
 144                         .arg("--print")
 145                         .arg("sysroot")
 146                         .output()
 147                         .ok()
 148                         .and_then(|out| String::from_utf8(out.stdout).ok())
 149                         .map(|s| s.trim().to_owned())
 150                 })
 151                 .or_else(|| option_env!("SYSROOT").map(String::from))
 152                 .expect("need to specify SYSROOT env var during clippy compilation, or use rustup or multirust");
 153
 154             // Setting RUSTC_WRAPPER causes Cargo to pass 'rustc' as the first argument.
 155             // We're invoking the compiler programmatically, so we ignore this/
 156             if orig_args.len() <= 1 {
 157                 std::process::exit(1);
 158             }
 159             if Path::new(&orig_args[1]).file_stem() == Some("rustc".as_ref()) {
 160                 // we still want to be able to invoke it normally though
 161                 orig_args.remove(1);
 162             }
 163             // this conditional check for the --sysroot flag is there so users can call
 164             // `clippy_driver` directly
 165             // without having to pass --sysroot or anything
 166             let mut args: Vec<String> = if have_sys_root_arg {
 167                 orig_args.clone()
 168             } else {
 169                 orig_args
 170                     .clone()
 171                     .into_iter()
 172                     .chain(Some("--sysroot".to_owned()))
 173                     .chain(Some(sys_root))
 174                     .collect()
 175             };
 176
 177             // this check ensures that dependencies are built but not linted and the final
 178             // crate is
 179             // linted but not built
 180             let clippy_enabled = env::var("CLIPPY_TESTS").ok().map_or(false, |val| val == "true")
 181                 || arg_value(&orig_args, "--emit", |val| val.split(',').any(|e| e == "metadata")).is_some();
 182
 183             if clippy_enabled {
 184                 args.extend_from_slice(&["--cfg".to_owned(), r#"feature="cargo-clippy""#.to_owned()]);
 185                 if let Ok(extra_args) = env::var("CLIPPY_ARGS") {
 186                     args.extend(extra_args.split("__CLIPPY_HACKERY__").filter_map(|s| {
 187                         if s.is_empty() {
 188                             None
 189                         } else {
 190                             Some(s.to_string())
 191                         }
 192                     }));
 193                 }
 194             }
 195
 196             let mut clippy = ClippyCallbacks;
 197             let mut default = rustc_driver::DefaultCallbacks;
 198             let callbacks: &mut (dyn rustc_driver::Callbacks + Send) =
 199                 if clippy_enabled { &mut clippy } else { &mut default };
 200             let args = args;
 201             rustc_driver::run_compiler(&args, callbacks, None, None)
 202         })
 203         .and_then(|result| result)
 204         .is_err() as i32,
 205     )
 206 }