Simplify

crates/base-db/src/input.rs

@@ -285,6 +285,7 @@ pub struct CrateData {
     /// For purposes of analysis, crates are anonymous (only names in
     /// `Dependency` matters), this name should only be used for UI.
     pub display_name: Option<CrateDisplayName>,
+    // FIXME: Arc this
     pub cfg_options: CfgOptions,
     /// The cfg options that could be used by the crate
     pub potential_cfg_options: Option<CfgOptions>,

crates/hir-def/src/data.rs

@@ -737,7 +737,7 @@ impl<'a> AssocItemCollector<'a> {
                     &AstIdWithPath::new(file_id, ast_id, Clone::clone(path)),
                     ctxt,
                     expand_to,
-                    self.expander.module.krate(),
+                    self.expander.krate(),
                     resolver,
                 ) {
                     Ok(Some(call_id)) => {

crates/hir-def/src/expander.rs

@@ -21,7 +21,6 @@ use crate::{
 pub struct Expander {
     cfg_options: CfgOptions,
     span_map: OnceCell<SpanMap>,
-    krate: CrateId,
     current_file_id: HirFileId,
     pub(crate) module: ModuleId,
     /// `recursion_depth == usize::MAX` indicates that the recursion limit has been reached.
@@ -45,10 +44,13 @@ impl Expander {
             recursion_limit,
             cfg_options: db.crate_graph()[module.krate].cfg_options.clone(),
             span_map: OnceCell::new(),
-            krate: module.krate,
         }
     }
 
+    pub fn krate(&self) -> CrateId {
+        self.module.krate
+    }
+
     pub fn enter_expand<T: ast::AstNode>(
         &mut self,
         db: &dyn DefDatabase,
@@ -112,7 +114,7 @@ impl Expander {
     pub(crate) fn parse_attrs(&self, db: &dyn DefDatabase, owner: &dyn ast::HasAttrs) -> Attrs {
         Attrs::filter(
             db,
-            self.krate,
+            self.krate(),
             RawAttrs::new(
                 db.upcast(),
                 owner,

crates/hir-ty/src/consteval.rs

@@ -77,30 +77,32 @@ pub(crate) fn path_to_const(
     resolver: &Resolver,
     path: &Path,
     mode: ParamLoweringMode,
-    args_lazy: impl FnOnce() -> Generics,
+    args: impl FnOnce() -> Option<Generics>,
     debruijn: DebruijnIndex,
     expected_ty: Ty,
 ) -> Option<Const> {
     match resolver.resolve_path_in_value_ns_fully(db.upcast(), path) {
         Some(ValueNs::GenericParam(p)) => {
             let ty = db.const_param_ty(p);
-            let args = args_lazy();
             let value = match mode {
                 ParamLoweringMode::Placeholder => {
                     ConstValue::Placeholder(to_placeholder_idx(db, p.into()))
                 }
-                ParamLoweringMode::Variable => match args.param_idx(p.into()) {
-                    Some(it) => ConstValue::BoundVar(BoundVar::new(debruijn, it)),
-                    None => {
-                        never!(
-                            "Generic list doesn't contain this param: {:?}, {:?}, {:?}",
-                            args,
-                            path,
-                            p
-                        );
-                        return None;
+                ParamLoweringMode::Variable => {
+                    let args = args();
+                    match args.as_ref().and_then(|args| args.param_idx(p.into())) {
+                        Some(it) => ConstValue::BoundVar(BoundVar::new(debruijn, it)),
+                        None => {
+                            never!(
+                                "Generic list doesn't contain this param: {:?}, {:?}, {:?}",
+                                args,
+                                path,
+                                p
+                            );
+                            return None;
+                        }
                     }
-                },
+                }
             };
             Some(ConstData { ty, value }.intern(Interner))
         }
@@ -285,7 +287,6 @@ pub(crate) fn eval_to_const(
     expr: ExprId,
     mode: ParamLoweringMode,
     ctx: &mut InferenceContext<'_>,
-    args: impl FnOnce() -> Generics,
     debruijn: DebruijnIndex,
 ) -> Const {
     let db = ctx.db;
@@ -304,7 +305,9 @@ pub(crate) fn eval_to_const(
     }
     if let Expr::Path(p) = &ctx.body.exprs[expr] {
         let resolver = &ctx.resolver;
-        if let Some(c) = path_to_const(db, resolver, p, mode, args, debruijn, infer[expr].clone()) {
+        if let Some(c) =
+            path_to_const(db, resolver, p, mode, || ctx.generics(), debruijn, infer[expr].clone())
+        {
             return c;
         }
     }

crates/hir-ty/src/infer.rs

@@ -60,7 +60,7 @@ use crate::{
     lower::ImplTraitLoweringMode,
     to_assoc_type_id,
     traits::FnTrait,
-    utils::{InTypeConstIdMetadata, UnevaluatedConstEvaluatorFolder},
+    utils::{Generics, InTypeConstIdMetadata, UnevaluatedConstEvaluatorFolder},
     AliasEq, AliasTy, Binders, ClosureId, Const, DomainGoal, GenericArg, Goal, ImplTraitId,
     ImplTraitIdx, InEnvironment, Interner, Lifetime, OpaqueTyId, ProjectionTy, Substitution,
     TraitEnvironment, Ty, TyBuilder, TyExt,
@@ -630,6 +630,10 @@ impl<'a> InferenceContext<'a> {
         }
     }
 
+    pub(crate) fn generics(&self) -> Option<Generics> {
+        Some(crate::utils::generics(self.db.upcast(), self.resolver.generic_def()?))
+    }
+
     // FIXME: This function should be private in module. It is currently only used in the consteval, since we need
     // `InferenceResult` in the middle of inference. See the fixme comment in `consteval::eval_to_const`. If you
     // used this function for another workaround, mention it here. If you really need this function and believe that

crates/hir-ty/src/infer/cast.rs

@@ -19,10 +19,6 @@ impl CastCheck {
         let expr_ty = table.resolve_ty_shallow(&self.expr_ty);
         let cast_ty = table.resolve_ty_shallow(&self.cast_ty);
 
-        if expr_ty.contains_unknown() || cast_ty.contains_unknown() {
-            return;
-        }
-
         if table.coerce(&expr_ty, &cast_ty).is_ok() {
             return;
         }

crates/hir-ty/src/infer/closure.rs

@@ -26,7 +26,7 @@ use crate::{
     mir::{BorrowKind, MirSpan, MutBorrowKind, ProjectionElem},
     to_chalk_trait_id,
     traits::FnTrait,
-    utils::{self, elaborate_clause_supertraits, generics, Generics},
+    utils::{self, elaborate_clause_supertraits, Generics},
     Adjust, Adjustment, AliasEq, AliasTy, Binders, BindingMode, ChalkTraitId, ClosureId, DynTy,
     DynTyExt, FnAbi, FnPointer, FnSig, Interner, OpaqueTy, ProjectionTyExt, Substitution, Ty,
     TyExt, WhereClause,
@@ -331,14 +331,10 @@ impl CapturedItemWithoutTy {
             place: self.place,
             kind: self.kind,
             span: self.span,
-            ty: replace_placeholder_with_binder(ctx.db, ctx.owner, ty),
+            ty: replace_placeholder_with_binder(ctx, ty),
         };
 
-        fn replace_placeholder_with_binder(
-            db: &dyn HirDatabase,
-            owner: DefWithBodyId,
-            ty: Ty,
-        ) -> Binders<Ty> {
+        fn replace_placeholder_with_binder(ctx: &mut InferenceContext<'_>, ty: Ty) -> Binders<Ty> {
             struct Filler<'a> {
                 db: &'a dyn HirDatabase,
                 generics: Generics,
@@ -379,12 +375,12 @@ impl CapturedItemWithoutTy {
                     Ok(BoundVar::new(outer_binder, idx).to_ty(Interner))
                 }
             }
-            let Some(generic_def) = owner.as_generic_def_id() else {
+            let Some(generics) = ctx.generics() else {
                 return Binders::empty(Interner, ty);
             };
-            let filler = &mut Filler { db, generics: generics(db.upcast(), generic_def) };
+            let filler = &mut Filler { db: ctx.db, generics };
             let result = ty.clone().try_fold_with(filler, DebruijnIndex::INNERMOST).unwrap_or(ty);
-            make_binders(db, &filler.generics, result)
+            make_binders(ctx.db, &filler.generics, result)
         }
     }
 }

crates/hir-ty/src/infer/expr.rs

@@ -1040,18 +1040,12 @@ impl InferenceContext<'_> {
 
                 (
                     elem_ty,
-                    if let Some(g_def) = self.owner.as_generic_def_id() {
-                        let generics = generics(self.db.upcast(), g_def);
-                        consteval::eval_to_const(
-                            repeat,
-                            ParamLoweringMode::Placeholder,
-                            self,
-                            || generics,
-                            DebruijnIndex::INNERMOST,
-                        )
-                    } else {
-                        consteval::usize_const(self.db, None, krate)
-                    },
+                    consteval::eval_to_const(
+                        repeat,
+                        ParamLoweringMode::Placeholder,
+                        self,
+                        DebruijnIndex::INNERMOST,
+                    ),
                 )
             }
         };
@@ -1852,7 +1846,7 @@ impl InferenceContext<'_> {
                             ty,
                             c,
                             ParamLoweringMode::Placeholder,
-                            || generics(this.db.upcast(), this.resolver.generic_def().unwrap()),
+                            || this.generics(),
                             DebruijnIndex::INNERMOST,
                         )
                     },

crates/hir-ty/src/infer/pat.rs

@@ -2,22 +2,22 @@
 
 use std::iter::repeat_with;
 
-use chalk_ir::Mutability;
 use hir_def::{
     body::Body,
     hir::{Binding, BindingAnnotation, BindingId, Expr, ExprId, ExprOrPatId, Literal, Pat, PatId},
     path::Path,
 };
 use hir_expand::name::Name;
+use stdx::TupleExt;
 
 use crate::{
     consteval::{try_const_usize, usize_const},
     error_lifetime,
     infer::{BindingMode, Expectation, InferenceContext, TypeMismatch},
     lower::lower_to_chalk_mutability,
     primitive::UintTy,
-    static_lifetime, InferenceDiagnostic, Interner, Scalar, Substitution, Ty, TyBuilder, TyExt,
-    TyKind,
+    static_lifetime, InferenceDiagnostic, Interner, Mutability, Scalar, Substitution, Ty,
+    TyBuilder, TyExt, TyKind,
 };
 
 /// Used to generalize patterns and assignee expressions.
@@ -90,9 +90,6 @@ impl InferenceContext<'_> {
 
         self.unify(&ty, expected);
 
-        let substs =
-            ty.as_adt().map(|(_, s)| s.clone()).unwrap_or_else(|| Substitution::empty(Interner));
-
         match def {
             _ if subs.is_empty() => {}
             Some(def) => {
@@ -109,26 +106,28 @@ impl InferenceContext<'_> {
                 let pre_iter = pre.iter().enumerate();
                 let post_iter = (post_idx_offset..).zip(post.iter());
 
+                let substs = ty.as_adt().map(TupleExt::tail);
+
                 for (i, &subpat) in pre_iter.chain(post_iter) {
-                    let field_def = {
+                    let expected_ty = {
                         match variant_data.field(&Name::new_tuple_field(i)) {
                             Some(local_id) => {
                                 if !visibilities[local_id]
                                     .is_visible_from(self.db.upcast(), self.resolver.module())
                                 {
                                     // FIXME(DIAGNOSE): private tuple field
                                 }
-                                Some(local_id)
+                                let f = field_types[local_id].clone();
+                                let expected_ty = match substs {
+                                    Some(substs) => f.substitute(Interner, substs),
+                                    None => f.substitute(Interner, &Substitution::empty(Interner)),
+                                };
+                                self.normalize_associated_types_in(expected_ty)
                             }
-                            None => None,
+                            None => self.err_ty(),
                         }
                     };
 
-                    let expected_ty = field_def.map_or(self.err_ty(), |f| {
-                        field_types[f].clone().substitute(Interner, &substs)
-                    });
-                    let expected_ty = self.normalize_associated_types_in(expected_ty);
-
                     T::infer(self, subpat, &expected_ty, default_bm);
                 }
             }
@@ -159,18 +158,17 @@ impl InferenceContext<'_> {
 
         self.unify(&ty, expected);
 
-        let substs =
-            ty.as_adt().map(|(_, s)| s.clone()).unwrap_or_else(|| Substitution::empty(Interner));
-
         match def {
             _ if subs.len() == 0 => {}
             Some(def) => {
                 let field_types = self.db.field_types(def);
                 let variant_data = def.variant_data(self.db.upcast());
                 let visibilities = self.db.field_visibilities(def);
 
+                let substs = ty.as_adt().map(TupleExt::tail);
+
                 for (name, inner) in subs {
-                    let field_def = {
+                    let expected_ty = {
                         match variant_data.field(&name) {
                             Some(local_id) => {
                                 if !visibilities[local_id]
@@ -181,23 +179,23 @@ impl InferenceContext<'_> {
                                         private: true,
                                     });
                                 }
-                                Some(local_id)
+                                let f = field_types[local_id].clone();
+                                let expected_ty = match substs {
+                                    Some(substs) => f.substitute(Interner, substs),
+                                    None => f.substitute(Interner, &Substitution::empty(Interner)),
+                                };
+                                self.normalize_associated_types_in(expected_ty)
                             }
                             None => {
                                 self.push_diagnostic(InferenceDiagnostic::NoSuchField {
                                     field: inner.into(),
                                     private: false,
                                 });
-                                None
+                                self.err_ty()
                             }
                         }
                     };
 
-                    let expected_ty = field_def.map_or(self.err_ty(), |f| {
-                        field_types[f].clone().substitute(Interner, &substs)
-                    });
-                    let expected_ty = self.normalize_associated_types_in(expected_ty);
-
                     T::infer(self, inner, &expected_ty, default_bm);
                 }
             }