src/driver.rs

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