Enable internal rustc lints

.github/workflows/ci.yml

@@ -83,6 +83,9 @@ jobs:
           sweep-cache: true
 
       - name: Run Clippy
+        env:
+          # Although we don't use any unstable options, this enables `rustc::internal` lints.
+          RUSTFLAGS: -Zunstable-options
         run: cargo clippy --workspace --all-targets ${{ matrix.features }} -- --deny warnings
 
   rustfmt:

bevy_lint/src/lib.rs

@@ -9,12 +9,19 @@
 #![feature(rustc_private)]
 // Allows chaining `if let` multiple times using `&&`.
 #![feature(let_chains)]
-// Warn on internal `rustc` lints that check for poor usage of internal compiler APIs.
+// Warn on internal `rustc` lints that check for poor usage of internal compiler APIs. Note that
+// you also need to pass `-Z unstable-options` to `rustc` for this to be enabled:
+// `RUSTFLAGS="-Zunstable-options" cargo check`
 #![warn(rustc::internal)]
+#![allow(
+    rustc::usage_of_ty_tykind,
+    reason = "Many false positives without a valid replacement."
+)]
 
 // This is a list of every single `rustc` crate used within this library. If you need another, add
 // it here!
 extern crate rustc_abi;
+extern crate rustc_data_structures;
 extern crate rustc_driver;
 extern crate rustc_errors;
 extern crate rustc_hir;

bevy_lint/src/lints/nursery/duplicate_bevy_dependencies.rs

@@ -60,13 +60,7 @@
 //! leafwing-input-manager = "0.16"
 //! ```
 
-use std::{
-    collections::{BTreeMap, HashMap},
-    ops::Range,
-    path::Path,
-    str::FromStr,
-    sync::Arc,
-};
+use std::{collections::BTreeMap, ops::Range, path::Path, str::FromStr, sync::Arc};
 
 use crate::declare_bevy_lint;
 use cargo_metadata::{
@@ -121,7 +115,7 @@ pub fn check(cx: &LateContext<'_>, metadata: &Metadata, bevy_symbol: Symbol) {
         let local_name = cx.tcx.crate_name(LOCAL_CRATE);
 
         // get the package name and the corresponding version of `bevy` that they depend on
-        let mut bevy_dependents = HashMap::new();
+        let mut bevy_dependents = BTreeMap::default();
         for package in &metadata.packages {
             for dependency in &package.dependencies {
                 if dependency.name.as_str() == "bevy"
@@ -155,7 +149,7 @@ fn lint_with_target_version(
     cargo_toml: &CargoToml,
     file: &Arc<SourceFile>,
     bevy_cargo: &Spanned<toml::Value>,
-    bevy_dependents: &HashMap<&str, VersionReq>,
+    bevy_dependents: &BTreeMap<&str, VersionReq>,
 ) {
     // Semver only supports checking if a given `VersionReq` matches a `Version` and not if two
     // `VersionReq` can successfully resolve to one `Version`. Therefore we try to parse the
@@ -191,7 +185,7 @@ fn lint_with_target_version(
 
 fn minimal_lint(
     cx: &LateContext<'_>,
-    bevy_dependents: &HashMap<&str, VersionReq>,
+    bevy_dependents: &BTreeMap<&str, VersionReq>,
     resolved: &Resolve,
 ) {
     // Examples of the underlying string representation of resolved crates

bevy_lint/src/lints/nursery/zst_query.rs

@@ -111,7 +111,7 @@ impl<'tcx> LateLintPass<'tcx> for ZstQuery {
                 hir_ty.span,
                 ZST_QUERY.lint.desc,
                 None,
-                query_kind.help(&peeled),
+                query_kind.help(peeled),
             );
         }
     }
@@ -130,7 +130,7 @@ impl QueryKind {
         }
     }
 
-    fn help(&self, ty: &Ty<'_>) -> String {
+    fn help(&self, ty: Ty<'_>) -> String {
         // It should be noted that `With<Foo>` is not always the best filter to suggest.
         // While it's most often going to be what users want, there's also `Added<Foo>`
         // and `Changed<Foo>` which might be more appropriate in some cases