Rollup merge of rust-lang#81680 - camsteffen:primty, r=oli-obk

Refactor `PrimitiveTypeTable` for Clippy

I removed `PrimitiveTypeTable` and added `PrimTy::ALL` and `PrimTy::from_name` in its place. This allows Clippy to use `PrimTy::from_name` for the `builtin_type_shadow` lint, and a `const` list of primitive types is deleted from Clippy code (the goal). All changes should be a little faster, if anything.

Author: jonas-schievink

compiler/rustc_hir/src/hir.rs

@@ -2058,6 +2058,28 @@ pub enum PrimTy {
 }
 
 impl PrimTy {
+    /// All of the primitive types
+    pub const ALL: [Self; 17] = [
+        // any changes here should also be reflected in `PrimTy::from_name`
+        Self::Int(IntTy::I8),
+        Self::Int(IntTy::I16),
+        Self::Int(IntTy::I32),
+        Self::Int(IntTy::I64),
+        Self::Int(IntTy::I128),
+        Self::Int(IntTy::Isize),
+        Self::Uint(UintTy::U8),
+        Self::Uint(UintTy::U16),
+        Self::Uint(UintTy::U32),
+        Self::Uint(UintTy::U64),
+        Self::Uint(UintTy::U128),
+        Self::Uint(UintTy::Usize),
+        Self::Float(FloatTy::F32),
+        Self::Float(FloatTy::F64),
+        Self::Bool,
+        Self::Char,
+        Self::Str,
+    ];
+
     pub fn name_str(self) -> &'static str {
         match self {
             PrimTy::Int(i) => i.name_str(),
@@ -2079,6 +2101,33 @@ impl PrimTy {
             PrimTy::Char => sym::char,
         }
     }
+
+    /// Returns the matching `PrimTy` for a `Symbol` such as "str" or "i32".
+    /// Returns `None` if no matching type is found.
+    pub fn from_name(name: Symbol) -> Option<Self> {
+        let ty = match name {
+            // any changes here should also be reflected in `PrimTy::ALL`
+            sym::i8 => Self::Int(IntTy::I8),
+            sym::i16 => Self::Int(IntTy::I16),
+            sym::i32 => Self::Int(IntTy::I32),
+            sym::i64 => Self::Int(IntTy::I64),
+            sym::i128 => Self::Int(IntTy::I128),
+            sym::isize => Self::Int(IntTy::Isize),
+            sym::u8 => Self::Uint(UintTy::U8),
+            sym::u16 => Self::Uint(UintTy::U16),
+            sym::u32 => Self::Uint(UintTy::U32),
+            sym::u64 => Self::Uint(UintTy::U64),
+            sym::u128 => Self::Uint(UintTy::U128),
+            sym::usize => Self::Uint(UintTy::Usize),
+            sym::f32 => Self::Float(FloatTy::F32),
+            sym::f64 => Self::Float(FloatTy::F64),
+            sym::bool => Self::Bool,
+            sym::char => Self::Char,
+            sym::str => Self::Str,
+            _ => return None,
+        };
+        Some(ty)
+    }
 }
 
 #[derive(Debug, HashStable_Generic)]

compiler/rustc_resolve/src/diagnostics.rs

@@ -9,6 +9,7 @@ use rustc_feature::BUILTIN_ATTRIBUTES;
 use rustc_hir::def::Namespace::{self, *};
 use rustc_hir::def::{self, CtorKind, CtorOf, DefKind, NonMacroAttrKind};
 use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX, LOCAL_CRATE};
+use rustc_hir::PrimTy;
 use rustc_middle::bug;
 use rustc_middle::ty::{self, DefIdTree};
 use rustc_session::Session;
@@ -718,10 +719,9 @@ impl<'a> Resolver<'a> {
                     }
                 }
                 Scope::BuiltinTypes => {
-                    let primitive_types = &this.primitive_type_table.primitive_types;
-                    suggestions.extend(primitive_types.iter().flat_map(|(name, prim_ty)| {
+                    suggestions.extend(PrimTy::ALL.iter().filter_map(|prim_ty| {
                         let res = Res::PrimTy(*prim_ty);
-                        filter_fn(res).then_some(TypoSuggestion::from_res(*name, res))
+                        filter_fn(res).then_some(TypoSuggestion::from_res(prim_ty.name(), res))
                     }))
                 }
             }

compiler/rustc_resolve/src/late.rs

@@ -20,7 +20,7 @@ use rustc_errors::DiagnosticId;
 use rustc_hir::def::Namespace::{self, *};
 use rustc_hir::def::{self, CtorKind, DefKind, PartialRes, PerNS};
 use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX};
-use rustc_hir::TraitCandidate;
+use rustc_hir::{PrimTy, TraitCandidate};
 use rustc_middle::{bug, span_bug};
 use rustc_session::lint;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
@@ -1927,7 +1927,7 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                     self.r.trait_map.insert(id, traits);
                 }
 
-                if self.r.primitive_type_table.primitive_types.contains_key(&path[0].ident.name) {
+                if PrimTy::from_name(path[0].ident.name).is_some() {
                     let mut std_path = Vec::with_capacity(1 + path.len());
 
                     std_path.push(Segment::from_ident(Ident::with_dummy_span(sym::std)));
@@ -2121,13 +2121,9 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
             // The same fallback is used when `a` resolves to nothing.
             PathResult::Module(ModuleOrUniformRoot::Module(_)) | PathResult::Failed { .. }
                 if (ns == TypeNS || path.len() > 1)
-                    && self
-                        .r
-                        .primitive_type_table
-                        .primitive_types
-                        .contains_key(&path[0].ident.name) =>
+                    && PrimTy::from_name(path[0].ident.name).is_some() =>
             {
-                let prim = self.r.primitive_type_table.primitive_types[&path[0].ident.name];
+                let prim = PrimTy::from_name(path[0].ident.name).unwrap();
                 PartialRes::with_unresolved_segments(Res::PrimTy(prim), path.len() - 1)
             }
             PathResult::Module(ModuleOrUniformRoot::Module(module)) => {

compiler/rustc_resolve/src/late/diagnostics.rs

@@ -1212,8 +1212,8 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
             // Add primitive types to the mix
             if filter_fn(Res::PrimTy(PrimTy::Bool)) {
                 names.extend(
-                    self.r.primitive_type_table.primitive_types.iter().map(|(name, prim_ty)| {
-                        TypoSuggestion::from_res(*name, Res::PrimTy(*prim_ty))
+                    PrimTy::ALL.iter().map(|prim_ty| {
+                        TypoSuggestion::from_res(prim_ty.name(), Res::PrimTy(*prim_ty))
                     }),
                 )
             }

compiler/rustc_resolve/src/lib.rs

@@ -25,7 +25,7 @@ use rustc_arena::{DroplessArena, TypedArena};
 use rustc_ast::node_id::NodeMap;
 use rustc_ast::unwrap_or;
 use rustc_ast::visit::{self, Visitor};
-use rustc_ast::{self as ast, FloatTy, IntTy, NodeId, UintTy};
+use rustc_ast::{self as ast, NodeId};
 use rustc_ast::{Crate, CRATE_NODE_ID};
 use rustc_ast::{ItemKind, Path};
 use rustc_ast_lowering::ResolverAstLowering;
@@ -39,8 +39,7 @@ use rustc_hir::def::Namespace::*;
 use rustc_hir::def::{self, CtorOf, DefKind, NonMacroAttrKind, PartialRes};
 use rustc_hir::def_id::{CrateNum, DefId, DefIdMap, LocalDefId, CRATE_DEF_INDEX};
 use rustc_hir::definitions::{DefKey, DefPathData, Definitions};
-use rustc_hir::PrimTy::{self, Bool, Char, Float, Int, Str, Uint};
-use rustc_hir::TraitCandidate;
+use rustc_hir::{PrimTy, TraitCandidate};
 use rustc_index::vec::IndexVec;
 use rustc_metadata::creader::{CStore, CrateLoader};
 use rustc_middle::hir::exports::ExportMap;
@@ -834,39 +833,6 @@ impl<'a> NameBinding<'a> {
     }
 }
 
-/// Interns the names of the primitive types.
-///
-/// All other types are defined somewhere and possibly imported, but the primitive ones need
-/// special handling, since they have no place of origin.
-struct PrimitiveTypeTable {
-    primitive_types: FxHashMap<Symbol, PrimTy>,
-}
-
-impl PrimitiveTypeTable {
-    fn new() -> PrimitiveTypeTable {
-        let mut table = FxHashMap::default();
-
-        table.insert(sym::bool, Bool);
-        table.insert(sym::char, Char);
-        table.insert(sym::f32, Float(FloatTy::F32));
-        table.insert(sym::f64, Float(FloatTy::F64));
-        table.insert(sym::isize, Int(IntTy::Isize));
-        table.insert(sym::i8, Int(IntTy::I8));
-        table.insert(sym::i16, Int(IntTy::I16));
-        table.insert(sym::i32, Int(IntTy::I32));
-        table.insert(sym::i64, Int(IntTy::I64));
-        table.insert(sym::i128, Int(IntTy::I128));
-        table.insert(sym::str, Str);
-        table.insert(sym::usize, Uint(UintTy::Usize));
-        table.insert(sym::u8, Uint(UintTy::U8));
-        table.insert(sym::u16, Uint(UintTy::U16));
-        table.insert(sym::u32, Uint(UintTy::U32));
-        table.insert(sym::u64, Uint(UintTy::U64));
-        table.insert(sym::u128, Uint(UintTy::U128));
-        Self { primitive_types: table }
-    }
-}
-
 #[derive(Debug, Default, Clone)]
 pub struct ExternPreludeEntry<'a> {
     extern_crate_item: Option<&'a NameBinding<'a>>,
@@ -912,9 +878,6 @@ pub struct Resolver<'a> {
     /// "self-confirming" import resolutions during import validation.
     unusable_binding: Option<&'a NameBinding<'a>>,
 
-    /// The idents for the primitive types.
-    primitive_type_table: PrimitiveTypeTable,
-
     /// Resolutions for nodes that have a single resolution.
     partial_res_map: NodeMap<PartialRes>,
     /// Resolutions for import nodes, which have multiple resolutions in different namespaces.
@@ -1284,8 +1247,6 @@ impl<'a> Resolver<'a> {
             last_import_segment: false,
             unusable_binding: None,
 
-            primitive_type_table: PrimitiveTypeTable::new(),
-
             partial_res_map: Default::default(),
             import_res_map: Default::default(),
             label_res_map: Default::default(),
@@ -1994,9 +1955,9 @@ impl<'a> Resolver<'a> {
         }
 
         if ns == TypeNS {
-            if let Some(prim_ty) = self.primitive_type_table.primitive_types.get(&ident.name) {
+            if let Some(prim_ty) = PrimTy::from_name(ident.name) {
                 let binding =
-                    (Res::PrimTy(*prim_ty), ty::Visibility::Public, DUMMY_SP, ExpnId::root())
+                    (Res::PrimTy(prim_ty), ty::Visibility::Public, DUMMY_SP, ExpnId::root())
                         .to_name_binding(self.arenas);
                 return Some(LexicalScopeBinding::Item(binding));
             }

compiler/rustc_resolve/src/macros.rs

@@ -21,6 +21,7 @@ use rustc_expand::expand::{AstFragment, Invocation, InvocationKind};
 use rustc_feature::is_builtin_attr_name;
 use rustc_hir::def::{self, DefKind, NonMacroAttrKind};
 use rustc_hir::def_id;
+use rustc_hir::PrimTy;
 use rustc_middle::middle::stability;
 use rustc_middle::ty;
 use rustc_session::lint::builtin::{SOFT_UNSTABLE, UNUSED_MACROS};
@@ -796,12 +797,10 @@ impl<'a> Resolver<'a> {
                         }
                         result
                     }
-                    Scope::BuiltinTypes => {
-                        match this.primitive_type_table.primitive_types.get(&ident.name).cloned() {
-                            Some(prim_ty) => ok(Res::PrimTy(prim_ty), DUMMY_SP, this.arenas),
-                            None => Err(Determinacy::Determined),
-                        }
-                    }
+                    Scope::BuiltinTypes => match PrimTy::from_name(ident.name) {
+                        Some(prim_ty) => ok(Res::PrimTy(prim_ty), DUMMY_SP, this.arenas),
+                        None => Err(Determinacy::Determined),
+                    },
                 };
 
                 match result {

src/tools/clippy/clippy_lints/src/misc_early.rs

@@ -1,11 +1,12 @@
-use crate::utils::{constants, snippet_opt, span_lint, span_lint_and_help, span_lint_and_sugg, span_lint_and_then};
+use crate::utils::{snippet_opt, span_lint, span_lint_and_help, span_lint_and_sugg, span_lint_and_then};
 use rustc_ast::ast::{
     BindingMode, Expr, ExprKind, GenericParamKind, Generics, Lit, LitFloatType, LitIntType, LitKind, Mutability,
     NodeId, Pat, PatKind, UnOp,
 };
 use rustc_ast::visit::FnKind;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::Applicability;
+use rustc_hir::PrimTy;
 use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -264,13 +265,12 @@ impl EarlyLintPass for MiscEarlyLints {
     fn check_generics(&mut self, cx: &EarlyContext<'_>, gen: &Generics) {
         for param in &gen.params {
             if let GenericParamKind::Type { .. } = param.kind {
-                let name = param.ident.as_str();
-                if constants::BUILTIN_TYPES.contains(&&*name) {
+                if let Some(prim_ty) = PrimTy::from_name(param.ident.name) {
                     span_lint(
                         cx,
                         BUILTIN_TYPE_SHADOW,
                         param.ident.span,
-                        &format!("this generic shadows the built-in type `{}`", name),
+                        &format!("this generic shadows the built-in type `{}`", prim_ty.name()),
                     );
                 }
             }

src/tools/clippy/clippy_lints/src/utils/constants.rs

@@ -8,7 +8,6 @@ pub mod author;
 pub mod camel_case;
 pub mod comparisons;
 pub mod conf;
-pub mod constants;
 mod diagnostics;
 pub mod eager_or_lazy;
 pub mod higher;