Implement another internal lints

src/bootstrap/bin/rustc.rs

@@ -307,6 +307,18 @@ fn main() {
 
     // This is required for internal lints.
     cmd.arg("-Zunstable-options");
+    if let Some(crate_name) = args.windows(2).find(|a| &*a[0] == "--crate-name") {
+        let crate_name = crate_name[1].to_string_lossy();
+        if crate_name.starts_with("rustc")
+            || crate_name.starts_with("syntax")
+            || crate_name == "arena"
+            || crate_name == "fmt_macros"
+        {
+            if stage != "0" {
+                cmd.arg("-Wrustc::internal");
+            }
+        }
+    }
 
     // Force all crates compiled by this compiler to (a) be unstable and (b)
     // allow the `rustc_private` feature to link to other unstable crates

src/libarena/lib.rs

@@ -12,7 +12,6 @@
        test(no_crate_inject, attr(deny(warnings))))]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #![feature(core_intrinsics)]

src/libfmt_macros/lib.rs

@@ -9,7 +9,6 @@
        test(attr(deny(warnings))))]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #![feature(nll)]

src/librustc/lib.rs

@@ -29,7 +29,6 @@
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #![feature(arbitrary_self_types)]

src/librustc/lint/context.rs

@@ -1341,6 +1341,7 @@ struct LateLintPassObjects<'a> {
     lints: &'a mut [LateLintPassObject],
 }
 
+#[cfg_attr(not(bootstrap), allow(rustc::lint_pass_impl_without_macro))]
 impl LintPass for LateLintPassObjects<'_> {
     fn name(&self) -> &'static str {
         panic!()
@@ -1510,6 +1511,7 @@ struct EarlyLintPassObjects<'a> {
     lints: &'a mut [EarlyLintPassObject],
 }
 
+#[cfg_attr(not(bootstrap), allow(rustc::lint_pass_impl_without_macro))]
 impl LintPass for EarlyLintPassObjects<'_> {
     fn name(&self) -> &'static str {
         panic!()

src/librustc/lint/internal.rs

@@ -7,11 +7,12 @@ use crate::lint::{
 };
 use errors::Applicability;
 use rustc_data_structures::fx::FxHashMap;
-use syntax::ast::Ident;
+use syntax::ast::{Ident, Item, ItemKind};
 use syntax::symbol::{sym, Symbol};
+use syntax_pos::ExpnInfo;
 
-declare_lint! {
-    pub DEFAULT_HASH_TYPES,
+declare_tool_lint! {
+    pub rustc::DEFAULT_HASH_TYPES,
     Allow,
     "forbid HashMap and HashSet and suggest the FxHash* variants"
 }
@@ -22,7 +23,7 @@ pub struct DefaultHashTypes {
 
 impl DefaultHashTypes {
     // we are allowed to use `HashMap` and `HashSet` as identifiers for implementing the lint itself
-    #[allow(internal)]
+    #[cfg_attr(not(bootstrap), allow(rustc::default_hash_types))]
     pub fn new() -> Self {
         let mut map = FxHashMap::default();
         map.insert(sym::HashMap, sym::FxHashMap);
@@ -36,40 +37,34 @@ impl_lint_pass!(DefaultHashTypes => [DEFAULT_HASH_TYPES]);
 impl EarlyLintPass for DefaultHashTypes {
     fn check_ident(&mut self, cx: &EarlyContext<'_>, ident: Ident) {
         if let Some(replace) = self.map.get(&ident.name) {
-            let msg = format!(
-                "Prefer {} over {}, it has better performance",
-                replace, ident
-            );
+            let msg = format!("Prefer {} over {}, it has better performance", replace, ident);
             let mut db = cx.struct_span_lint(DEFAULT_HASH_TYPES, ident.span, &msg);
             db.span_suggestion(
                 ident.span,
                 "use",
                 replace.to_string(),
                 Applicability::MaybeIncorrect, // FxHashMap, ... needs another import
             );
-            db.note(&format!(
-                "a `use rustc_data_structures::fx::{}` may be necessary",
-                replace
-            ))
-            .emit();
+            db.note(&format!("a `use rustc_data_structures::fx::{}` may be necessary", replace))
+                .emit();
         }
     }
 }
 
-declare_lint! {
-    pub USAGE_OF_TY_TYKIND,
+declare_tool_lint! {
+    pub rustc::USAGE_OF_TY_TYKIND,
     Allow,
     "usage of `ty::TyKind` outside of the `ty::sty` module"
 }
 
-declare_lint! {
-    pub TY_PASS_BY_REFERENCE,
+declare_tool_lint! {
+    pub rustc::TY_PASS_BY_REFERENCE,
     Allow,
     "passing `Ty` or `TyCtxt` by reference"
 }
 
-declare_lint! {
-    pub USAGE_OF_QUALIFIED_TY,
+declare_tool_lint! {
+    pub rustc::USAGE_OF_QUALIFIED_TY,
     Allow,
     "using `ty::{Ty,TyCtxt}` instead of importing it"
 }
@@ -137,13 +132,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for TyTyKind {
                     }
                 }
             }
-            TyKind::Rptr(
-                _,
-                MutTy {
-                    ty: inner_ty,
-                    mutbl: Mutability::MutImmutable,
-                },
-            ) => {
+            TyKind::Rptr(_, MutTy { ty: inner_ty, mutbl: Mutability::MutImmutable }) => {
                 if let Some(impl_did) = cx.tcx.impl_of_method(ty.hir_id.owner_def_id()) {
                     if cx.tcx.impl_trait_ref(impl_did).is_some() {
                         return;
@@ -225,3 +214,44 @@ fn gen_args(segment: &PathSegment) -> String {
 
     String::new()
 }
+
+declare_tool_lint! {
+    pub rustc::LINT_PASS_IMPL_WITHOUT_MACRO,
+    Allow,
+    "`impl LintPass` without the `declare_lint_pass!` or `impl_lint_pass!` macros"
+}
+
+declare_lint_pass!(LintPassImpl => [LINT_PASS_IMPL_WITHOUT_MACRO]);
+
+impl EarlyLintPass for LintPassImpl {
+    fn check_item(&mut self, cx: &EarlyContext<'_>, item: &Item) {
+        if let ItemKind::Impl(_, _, _, _, Some(lint_pass), _, _) = &item.node {
+            if let Some(last) = lint_pass.path.segments.last() {
+                if last.ident.name == sym::LintPass {
+                    match &lint_pass.path.span.ctxt().outer_expn_info() {
+                        Some(info) if is_lint_pass_expansion(info) => {}
+                        _ => {
+                            cx.struct_span_lint(
+                                LINT_PASS_IMPL_WITHOUT_MACRO,
+                                lint_pass.path.span,
+                                "implementing `LintPass` by hand",
+                            )
+                            .help("try using `declare_lint_pass!` or `impl_lint_pass!` instead")
+                            .emit();
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+fn is_lint_pass_expansion(expn_info: &ExpnInfo) -> bool {
+    if expn_info.format.name() == sym::impl_lint_pass {
+        true
+    } else if let Some(info) = expn_info.call_site.ctxt().outer_expn_info() {
+        info.format.name() == sym::declare_lint_pass
+    } else {
+        false
+    }
+}

src/librustc/ty/mod.rs

@@ -1,6 +1,6 @@
 // ignore-tidy-filelength
 
-#![allow(usage_of_ty_tykind)]
+#![cfg_attr(not(bootstrap), allow(rustc::usage_of_ty_tykind))]
 
 pub use self::Variance::*;
 pub use self::AssocItemContainer::*;

src/librustc_allocator/lib.rs

@@ -2,7 +2,6 @@
 #![feature(rustc_private)]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 pub mod expand;

src/librustc_borrowck/lib.rs

@@ -2,7 +2,6 @@
 
 #![allow(non_camel_case_types)]
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #![feature(in_band_lifetimes)]

src/librustc_codegen_llvm/lib.rs

@@ -22,7 +22,6 @@
 #![feature(static_nobundle)]
 #![feature(trusted_len)]
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 use back::write::{create_target_machine, create_informational_target_machine};

src/librustc_codegen_ssa/lib.rs

@@ -13,7 +13,6 @@
 #![allow(unused_attributes)]
 #![allow(dead_code)]
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #![recursion_limit="256"]

src/librustc_codegen_utils/lib.rs

@@ -17,7 +17,6 @@
 #![recursion_limit="256"]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #[macro_use]

src/librustc_data_structures/lib.rs

@@ -27,6 +27,7 @@
 #![cfg_attr(test, feature(test))]
 
 #![deny(rust_2018_idioms)]
+#![cfg_attr(not(bootstrap), allow(rustc::default_hash_types))]
 
 #[macro_use]
 extern crate log;

src/librustc_driver/lib.rs

@@ -17,7 +17,6 @@
 #![recursion_limit="256"]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 pub extern crate getopts;

src/librustc_errors/lib.rs

@@ -10,7 +10,6 @@
 #![feature(nll)]
 #![feature(optin_builtin_traits)]
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #[allow(unused_extern_crates)]

src/librustc_incremental/lib.rs

@@ -9,7 +9,6 @@
 #![recursion_limit="256"]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #[macro_use] extern crate rustc;

src/librustc_interface/lib.rs

@@ -7,7 +7,6 @@
 #![cfg_attr(unix, feature(libc))]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #![allow(unused_imports)]

src/librustc_lint/lib.rs

@@ -20,7 +20,6 @@
 #![recursion_limit="256"]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #[macro_use]
@@ -493,15 +492,17 @@ pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
 
 pub fn register_internals(store: &mut lint::LintStore, sess: Option<&Session>) {
     store.register_early_pass(sess, false, false, box DefaultHashTypes::new());
+    store.register_early_pass(sess, false, false, box LintPassImpl);
     store.register_late_pass(sess, false, false, false, box TyTyKind);
     store.register_group(
         sess,
         false,
-        "internal",
+        "rustc::internal",
         None,
         vec![
             LintId::of(DEFAULT_HASH_TYPES),
             LintId::of(USAGE_OF_TY_TYKIND),
+            LintId::of(LINT_PASS_IMPL_WITHOUT_MACRO),
             LintId::of(TY_PASS_BY_REFERENCE),
             LintId::of(USAGE_OF_QUALIFIED_TY),
         ],

src/librustc_macros/src/lib.rs

@@ -1,5 +1,6 @@
 #![feature(proc_macro_hygiene)]
 #![deny(rust_2018_idioms)]
+#![cfg_attr(not(bootstrap), allow(rustc::default_hash_types))]
 
 extern crate proc_macro;
 

src/librustc_metadata/lib.rs

@@ -15,7 +15,6 @@
 #![recursion_limit="256"]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 extern crate libc;

src/librustc_mir/lib.rs

@@ -28,7 +28,6 @@ Rust MIR: a lowered representation of Rust. Also: an experiment!
 #![recursion_limit="256"]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #[macro_use] extern crate log;

src/librustc_passes/lib.rs

@@ -14,7 +14,6 @@
 #![recursion_limit="256"]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #[macro_use]

src/librustc_privacy/lib.rs

@@ -1,7 +1,6 @@
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #![feature(in_band_lifetimes)]

src/librustc_resolve/lib.rs

@@ -11,7 +11,6 @@
 #![recursion_limit="256"]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 pub use rustc::hir::def::{Namespace, PerNS};

src/librustc_save_analysis/lib.rs

@@ -1,7 +1,6 @@
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
 #![feature(nll)]
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 #![allow(unused_attributes)]
 

src/librustc_target/lib.rs

@@ -16,7 +16,6 @@
 #![feature(step_trait)]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #[macro_use] extern crate log;

src/librustc_traits/lib.rs

@@ -2,7 +2,6 @@
 //! the guts are broken up into modules; see the comments in those modules.
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #![feature(crate_visibility_modifier)]

src/librustc_typeck/lib.rs

@@ -73,7 +73,6 @@ This API is completely unstable and subject to change.
 #![recursion_limit="256"]
 
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #[macro_use] extern crate log;

src/librustdoc/lib.rs

@@ -1,5 +1,4 @@
 #![deny(rust_2018_idioms)]
-#![deny(internal)]
 #![deny(unused_lifetimes)]
 
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/",