Lower const params with a bad id

crates/base-db/src/fixture.rs

@@ -215,7 +215,7 @@ impl ChangeFixture {
                 None,
                 default_cfg,
                 Default::default(),
-                Env::default(),
+                Env::new_for_test_fixture(),
                 false,
                 CrateOrigin::Local { repo: None, name: None },
                 default_target_data_layout
@@ -259,7 +259,7 @@ impl ChangeFixture {
                 None,
                 Default::default(),
                 Default::default(),
-                Env::default(),
+                Env::new_for_test_fixture(),
                 false,
                 CrateOrigin::Lang(LangCrateOrigin::Core),
                 target_layout.clone(),
@@ -298,7 +298,7 @@ impl ChangeFixture {
                 None,
                 Default::default(),
                 Default::default(),
-                Env::default(),
+                Env::new_for_test_fixture(),
                 true,
                 CrateOrigin::Local { repo: None, name: None },
                 target_layout,

crates/base-db/src/input.rs

@@ -151,6 +151,12 @@ pub enum CrateOrigin {
     Lang(LangCrateOrigin),
 }
 
+impl CrateOrigin {
+    pub fn is_local(&self) -> bool {
+        matches!(self, CrateOrigin::Local { .. })
+    }
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub enum LangCrateOrigin {
     Alloc,
@@ -333,6 +339,17 @@ pub struct Env {
     entries: FxHashMap<String, String>,
 }
 
+impl Env {
+    pub fn new_for_test_fixture() -> Self {
+        Env {
+            entries: FxHashMap::from_iter([(
+                String::from("__ra_is_test_fixture"),
+                String::from("__ra_is_test_fixture"),
+            )]),
+        }
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct Dependency {
     pub crate_id: CrateId,

crates/hir-def/src/body.rs

@@ -118,7 +118,7 @@ impl Body {
         let _p = profile::span("body_with_source_map_query");
         let mut params = None;
 
-        let (file_id, module, body, is_async_fn) = {
+        let (file_id, body, is_async_fn) = {
             match def {
                 DefWithBodyId::FunctionId(f) => {
                     let data = db.function_data(f);
@@ -138,31 +138,29 @@ impl Body {
                             }),
                         )
                     });
-                    (
-                        src.file_id,
-                        f.module(db),
-                        src.value.body().map(ast::Expr::from),
-                        data.has_async_kw(),
-                    )
+                    (src.file_id, src.value.body().map(ast::Expr::from), data.has_async_kw())
                 }
                 DefWithBodyId::ConstId(c) => {
                     let c = c.lookup(db);
                     let src = c.source(db);
-                    (src.file_id, c.module(db), src.value.body(), false)
+                    (src.file_id, src.value.body(), false)
                 }
                 DefWithBodyId::StaticId(s) => {
                     let s = s.lookup(db);
                     let src = s.source(db);
-                    (src.file_id, s.module(db), src.value.body(), false)
+                    (src.file_id, src.value.body(), false)
                 }
                 DefWithBodyId::VariantId(v) => {
-                    let e = v.parent.lookup(db);
                     let src = v.parent.child_source(db);
                     let variant = &src.value[v.local_id];
-                    (src.file_id, e.container, variant.expr(), false)
+                    (src.file_id, variant.expr(), false)
+                }
+                DefWithBodyId::InTypeConstId(c) => {
+                    (c.lookup(db).0.file_id, Some(c.source(db)), false)
                 }
             }
         };
+        let module = def.module(db);
         let expander = Expander::new(db, file_id, module);
         let (mut body, source_map) =
             Body::new(db, def, expander, params, body, module.krate, is_async_fn);

crates/hir-def/src/body/pretty.rs

@@ -40,6 +40,7 @@ pub(super) fn print_body_hir(db: &dyn DefDatabase, body: &Body, owner: DefWithBo
             };
             format!("const {name} = ")
         }
+        DefWithBodyId::InTypeConstId(_) => format!("In type const = "),
         DefWithBodyId::VariantId(it) => {
             let src = it.parent.child_source(db);
             let variant = &src.value[it.local_id];

crates/hir-def/src/db.rs

@@ -24,9 +24,10 @@ use crate::{
     visibility::{self, Visibility},
     AnonymousConstId, AttrDefId, BlockId, BlockLoc, ConstId, ConstLoc, DefWithBodyId, EnumId,
     EnumLoc, ExternBlockId, ExternBlockLoc, FunctionId, FunctionLoc, GenericDefId, ImplId, ImplLoc,
-    LocalEnumVariantId, LocalFieldId, Macro2Id, Macro2Loc, MacroRulesId, MacroRulesLoc,
-    ProcMacroId, ProcMacroLoc, StaticId, StaticLoc, StructId, StructLoc, TraitAliasId,
-    TraitAliasLoc, TraitId, TraitLoc, TypeAliasId, TypeAliasLoc, UnionId, UnionLoc, VariantId,
+    InTypeConstId, LocalEnumVariantId, LocalFieldId, Macro2Id, Macro2Loc, MacroRulesId,
+    MacroRulesLoc, ProcMacroId, ProcMacroLoc, StaticId, StaticLoc, StructId, StructLoc,
+    TraitAliasId, TraitAliasLoc, TraitId, TraitLoc, TypeAliasId, TypeAliasLoc, TypeOwnerId,
+    UnionId, UnionLoc, VariantId,
 };
 
 #[salsa::query_group(InternDatabaseStorage)]
@@ -63,6 +64,11 @@ pub trait InternDatabase: SourceDatabase {
     fn intern_macro_rules(&self, loc: MacroRulesLoc) -> MacroRulesId;
     #[salsa::interned]
     fn intern_anonymous_const(&self, id: (DefWithBodyId, ExprId)) -> AnonymousConstId;
+    #[salsa::interned]
+    fn intern_in_type_const(
+        &self,
+        id: (hir_expand::InFile<hir_expand::ast_id_map::FileAstId<ast::Expr>>, TypeOwnerId),
+    ) -> InTypeConstId;
 }
 
 #[salsa::query_group(DefDatabaseStorage)]

crates/hir-def/src/expander.rs

@@ -155,7 +155,7 @@ impl Expander {
     }
 
     pub(crate) fn parse_path(&mut self, db: &dyn DefDatabase, path: ast::Path) -> Option<Path> {
-        let ctx = LowerCtx::with_hygiene(db, &self.cfg_expander.hygiene);
+        let ctx = LowerCtx::new(db, &self.cfg_expander.hygiene, self.current_file_id);
         Path::from_src(path, &ctx)
     }
 

crates/hir-def/src/hir/type_ref.rs

@@ -5,9 +5,10 @@ use core::fmt;
 use std::fmt::Write;
 
 use hir_expand::{
+    ast_id_map::FileAstId,
     db::ExpandDatabase,
     name::{AsName, Name},
-    AstId,
+    AstId, InFile,
 };
 use intern::Interned;
 use syntax::ast::{self, HasName};
@@ -118,7 +119,7 @@ pub enum TypeRef {
     Reference(Box<TypeRef>, Option<LifetimeRef>, Mutability),
     // FIXME: for full const generics, the latter element (length) here is going to have to be an
     // expression that is further lowered later in hir_ty.
-    Array(Box<TypeRef>, ConstRefOrPath),
+    Array(Box<TypeRef>, ConstRef),
     Slice(Box<TypeRef>),
     /// A fn pointer. Last element of the vector is the return type.
     Fn(Vec<(Option<Name>, TypeRef)>, bool /*varargs*/, bool /*is_unsafe*/),
@@ -190,7 +191,7 @@ impl TypeRef {
                 // `hir_def::body::lower` to lower this into an `Expr` and then evaluate it at the
                 // `hir_ty` level, which would allow knowing the type of:
                 // let v: [u8; 2 + 2] = [0u8; 4];
-                let len = ConstRefOrPath::from_expr_opt(inner.expr());
+                let len = ConstRef::from_expr_opt(ctx, inner.expr());
                 TypeRef::Array(Box::new(TypeRef::from_ast_opt(ctx, inner.ty())), len)
             }
             ast::Type::SliceType(inner) => {
@@ -380,73 +381,84 @@ impl TypeBound {
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub enum ConstRefOrPath {
-    Scalar(ConstRef),
+pub enum ConstRef {
+    Scalar(ConcreteConstRef),
     Path(Name),
+    Complex(InFile<FileAstId<ast::Expr>>),
 }
 
-impl ConstRefOrPath {
-    pub(crate) fn from_expr_opt(expr: Option<ast::Expr>) -> Self {
+impl ConstRef {
+    pub(crate) fn from_expr_opt(lower_ctx: &LowerCtx<'_>, expr: Option<ast::Expr>) -> Self {
         match expr {
-            Some(x) => Self::from_expr(x),
-            None => Self::Scalar(ConstRef::Unknown),
+            Some(x) => {
+                let ast_id = lower_ctx.ast_id(&x);
+                Self::from_expr(x, ast_id)
+            }
+            None => Self::Scalar(ConcreteConstRef::Unknown),
         }
     }
 
     pub fn display<'a>(&'a self, db: &'a dyn ExpandDatabase) -> impl fmt::Display + 'a {
-        struct Display<'a>(&'a dyn ExpandDatabase, &'a ConstRefOrPath);
+        struct Display<'a>(&'a dyn ExpandDatabase, &'a ConstRef);
         impl fmt::Display for Display<'_> {
             fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
                 match self.1 {
-                    ConstRefOrPath::Scalar(s) => s.fmt(f),
-                    ConstRefOrPath::Path(n) => n.display(self.0).fmt(f),
+                    ConstRef::Scalar(s) => s.fmt(f),
+                    ConstRef::Path(n) => n.display(self.0).fmt(f),
+                    ConstRef::Complex(_) => f.write_str("{const}"),
                 }
             }
         }
         Display(db, self)
     }
 
-    // FIXME: as per the comments on `TypeRef::Array`, this evaluation should not happen at this
-    // parse stage.
-    fn from_expr(expr: ast::Expr) -> Self {
+    // We special case literals and single identifiers, to speed up things.
+    fn from_expr(expr: ast::Expr, ast_id: Option<InFile<FileAstId<ast::Expr>>>) -> Self {
+        fn is_path_ident(p: &ast::PathExpr) -> bool {
+            let Some(path) = p.path() else {
+                return false;
+            };
+            if path.coloncolon_token().is_some() {
+                return false;
+            }
+            if let Some(s) = path.segment() {
+                if s.coloncolon_token().is_some() || s.generic_arg_list().is_some() {
+                    return false;
+                }
+            }
+            true
+        }
         match expr {
-            ast::Expr::PathExpr(p) => {
+            ast::Expr::PathExpr(p) if is_path_ident(&p) => {
                 match p.path().and_then(|x| x.segment()).and_then(|x| x.name_ref()) {
                     Some(x) => Self::Path(x.as_name()),
-                    None => Self::Scalar(ConstRef::Unknown),
+                    None => Self::Scalar(ConcreteConstRef::Unknown),
                 }
             }
-            ast::Expr::PrefixExpr(prefix_expr) => match prefix_expr.op_kind() {
-                Some(ast::UnaryOp::Neg) => {
-                    let unsigned = Self::from_expr_opt(prefix_expr.expr());
-                    // Add sign
-                    match unsigned {
-                        Self::Scalar(ConstRef::UInt(num)) => {
-                            Self::Scalar(ConstRef::Int(-(num as i128)))
-                        }
-                        other => other,
-                    }
-                }
-                _ => Self::from_expr_opt(prefix_expr.expr()),
-            },
             ast::Expr::Literal(literal) => Self::Scalar(match literal.kind() {
                 ast::LiteralKind::IntNumber(num) => {
-                    num.value().map(ConstRef::UInt).unwrap_or(ConstRef::Unknown)
+                    num.value().map(ConcreteConstRef::UInt).unwrap_or(ConcreteConstRef::Unknown)
                 }
                 ast::LiteralKind::Char(c) => {
-                    c.value().map(ConstRef::Char).unwrap_or(ConstRef::Unknown)
+                    c.value().map(ConcreteConstRef::Char).unwrap_or(ConcreteConstRef::Unknown)
                 }
-                ast::LiteralKind::Bool(f) => ConstRef::Bool(f),
-                _ => ConstRef::Unknown,
+                ast::LiteralKind::Bool(f) => ConcreteConstRef::Bool(f),
+                _ => ConcreteConstRef::Unknown,
             }),
-            _ => Self::Scalar(ConstRef::Unknown),
+            _ => {
+                if let Some(ast_id) = ast_id {
+                    Self::Complex(ast_id)
+                } else {
+                    Self::Scalar(ConcreteConstRef::Unknown)
+                }
+            }
         }
     }
 }
 
 /// A concrete constant value
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub enum ConstRef {
+pub enum ConcreteConstRef {
     Int(i128),
     UInt(u128),
     Bool(bool),
@@ -460,18 +472,20 @@ pub enum ConstRef {
     Unknown,
 }
 
-impl ConstRef {
+impl ConcreteConstRef {
     pub fn builtin_type(&self) -> BuiltinType {
         match self {
-            ConstRef::UInt(_) | ConstRef::Unknown => BuiltinType::Uint(BuiltinUint::U128),
-            ConstRef::Int(_) => BuiltinType::Int(BuiltinInt::I128),
-            ConstRef::Char(_) => BuiltinType::Char,
-            ConstRef::Bool(_) => BuiltinType::Bool,
+            ConcreteConstRef::UInt(_) | ConcreteConstRef::Unknown => {
+                BuiltinType::Uint(BuiltinUint::U128)
+            }
+            ConcreteConstRef::Int(_) => BuiltinType::Int(BuiltinInt::I128),
+            ConcreteConstRef::Char(_) => BuiltinType::Char,
+            ConcreteConstRef::Bool(_) => BuiltinType::Bool,
         }
     }
 }
 
-impl From<Literal> for ConstRef {
+impl From<Literal> for ConcreteConstRef {
     fn from(literal: Literal) -> Self {
         match literal {
             Literal::Char(c) => Self::Char(c),
@@ -483,14 +497,14 @@ impl From<Literal> for ConstRef {
     }
 }
 
-impl std::fmt::Display for ConstRef {
+impl std::fmt::Display for ConcreteConstRef {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
         match self {
-            ConstRef::Int(num) => num.fmt(f),
-            ConstRef::UInt(num) => num.fmt(f),
-            ConstRef::Bool(flag) => flag.fmt(f),
-            ConstRef::Char(c) => write!(f, "'{c}'"),
-            ConstRef::Unknown => f.write_char('_'),
+            ConcreteConstRef::Int(num) => num.fmt(f),
+            ConcreteConstRef::UInt(num) => num.fmt(f),
+            ConcreteConstRef::Bool(flag) => flag.fmt(f),
+            ConcreteConstRef::Char(c) => write!(f, "'{c}'"),
+            ConcreteConstRef::Unknown => f.write_char('_'),
         }
     }
 }