src/driver.rs

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