diff --git a/crates/hir-def/src/data.rs b/crates/hir-def/src/data.rs index c5bbd4edba9e..bec662787728 100644 --- a/crates/hir-def/src/data.rs +++ b/crates/hir-def/src/data.rs @@ -250,6 +250,7 @@ bitflags::bitflags! { const RUSTC_HAS_INCOHERENT_INHERENT_IMPLS = 1 << 3; const SKIP_ARRAY_DURING_METHOD_DISPATCH = 1 << 4; const SKIP_BOXED_SLICE_DURING_METHOD_DISPATCH = 1 << 5; + const RUSTC_PAREN_SUGAR = 1 << 6; } } @@ -294,6 +295,9 @@ impl TraitData { if attrs.by_key(&sym::rustc_has_incoherent_inherent_impls).exists() { flags |= TraitFlags::RUSTC_HAS_INCOHERENT_INHERENT_IMPLS; } + if attrs.by_key(&sym::rustc_paren_sugar).exists() { + flags |= TraitFlags::RUSTC_PAREN_SUGAR; + } let mut skip_array_during_method_dispatch = attrs.by_key(&sym::rustc_skip_array_during_method_dispatch).exists(); diff --git a/crates/hir-def/src/path.rs b/crates/hir-def/src/path.rs index e59c37104dd6..e6c2504d07a5 100644 --- a/crates/hir-def/src/path.rs +++ b/crates/hir-def/src/path.rs @@ -173,10 +173,7 @@ impl Path { segments: path.mod_path().segments(), generic_args: Some(path.generic_args()), }, - Path::LangItem(_, seg) => PathSegments { - segments: seg.as_ref().map_or(&[], |seg| std::slice::from_ref(seg)), - generic_args: None, - }, + Path::LangItem(_, seg) => PathSegments { segments: seg.as_slice(), generic_args: None }, } } @@ -240,6 +237,11 @@ pub struct PathSegment<'a> { pub args_and_bindings: Option<&'a GenericArgs>, } +impl PathSegment<'_> { + pub const MISSING: PathSegment<'static> = + PathSegment { name: &Name::missing(), args_and_bindings: None }; +} + #[derive(Debug, Clone, Copy)] pub struct PathSegments<'a> { segments: &'a [Name], diff --git a/crates/hir-def/src/resolver.rs b/crates/hir-def/src/resolver.rs index 7e13ae2f7a1b..9dfb6e3cc4b7 100644 --- a/crates/hir-def/src/resolver.rs +++ b/crates/hir-def/src/resolver.rs @@ -327,8 +327,9 @@ impl Resolver { | LangItemTarget::ImplDef(_) | LangItemTarget::Static(_) => return None, }; + // Remaining segments start from 0 because lang paths have no segments other than the remaining. return Some(( - ResolveValueResult::Partial(type_ns, 1, None), + ResolveValueResult::Partial(type_ns, 0, None), ResolvePathResultPrefixInfo::default(), )); } diff --git a/crates/hir-expand/src/name.rs b/crates/hir-expand/src/name.rs index 21e5fb5ef9e1..0758bd4515ef 100644 --- a/crates/hir-expand/src/name.rs +++ b/crates/hir-expand/src/name.rs @@ -142,8 +142,8 @@ impl Name { /// Ideally, we want a `gensym` semantics for missing names -- each missing /// name is equal only to itself. It's not clear how to implement this in /// salsa though, so we punt on that bit for a moment. - pub fn missing() -> Name { - Name { symbol: sym::MISSING_NAME.clone(), ctx: () } + pub const fn missing() -> Name { + Name { symbol: sym::consts::MISSING_NAME, ctx: () } } /// Returns true if this is a fake name for things missing in the source code. See diff --git a/crates/hir-ty/src/infer.rs b/crates/hir-ty/src/infer.rs index 617ebba8811e..3ac2d90468f4 100644 --- a/crates/hir-ty/src/infer.rs +++ b/crates/hir-ty/src/infer.rs @@ -16,7 +16,7 @@ pub(crate) mod cast; pub(crate) mod closure; mod coerce; -mod diagnostics; +pub(crate) mod diagnostics; mod expr; mod mutability; mod pat; @@ -1480,21 +1480,22 @@ impl<'a> InferenceContext<'a> { &self.diagnostics, InferenceTyDiagnosticSource::Body, ); + let mut path_ctx = ctx.at_path(path, node); let (resolution, unresolved) = if value_ns { - let Some(res) = ctx.resolve_path_in_value_ns(path, node, HygieneId::ROOT) else { + let Some(res) = path_ctx.resolve_path_in_value_ns(HygieneId::ROOT) else { return (self.err_ty(), None); }; match res { ResolveValueResult::ValueNs(value, _) => match value { ValueNs::EnumVariantId(var) => { - let substs = ctx.substs_from_path(path, var.into(), true); + let substs = path_ctx.substs_from_path(var.into(), true); drop(ctx); let ty = self.db.ty(var.lookup(self.db.upcast()).parent.into()); let ty = self.insert_type_vars(ty.substitute(Interner, &substs)); return (ty, Some(var.into())); } ValueNs::StructId(strukt) => { - let substs = ctx.substs_from_path(path, strukt.into(), true); + let substs = path_ctx.substs_from_path(strukt.into(), true); drop(ctx); let ty = self.db.ty(strukt.into()); let ty = self.insert_type_vars(ty.substitute(Interner, &substs)); @@ -1509,7 +1510,7 @@ impl<'a> InferenceContext<'a> { ResolveValueResult::Partial(typens, unresolved, _) => (typens, Some(unresolved)), } } else { - match ctx.resolve_path_in_type_ns(path, node) { + match path_ctx.resolve_path_in_type_ns() { Some((it, idx)) => (it, idx), None => return (self.err_ty(), None), } @@ -1520,21 +1521,21 @@ impl<'a> InferenceContext<'a> { }; return match resolution { TypeNs::AdtId(AdtId::StructId(strukt)) => { - let substs = ctx.substs_from_path(path, strukt.into(), true); + let substs = path_ctx.substs_from_path(strukt.into(), true); drop(ctx); let ty = self.db.ty(strukt.into()); let ty = self.insert_type_vars(ty.substitute(Interner, &substs)); forbid_unresolved_segments((ty, Some(strukt.into())), unresolved) } TypeNs::AdtId(AdtId::UnionId(u)) => { - let substs = ctx.substs_from_path(path, u.into(), true); + let substs = path_ctx.substs_from_path(u.into(), true); drop(ctx); let ty = self.db.ty(u.into()); let ty = self.insert_type_vars(ty.substitute(Interner, &substs)); forbid_unresolved_segments((ty, Some(u.into())), unresolved) } TypeNs::EnumVariantId(var) => { - let substs = ctx.substs_from_path(path, var.into(), true); + let substs = path_ctx.substs_from_path(var.into(), true); drop(ctx); let ty = self.db.ty(var.lookup(self.db.upcast()).parent.into()); let ty = self.insert_type_vars(ty.substitute(Interner, &substs)); @@ -1545,31 +1546,32 @@ impl<'a> InferenceContext<'a> { let substs = generics.placeholder_subst(self.db); let mut ty = self.db.impl_self_ty(impl_id).substitute(Interner, &substs); - let Some(mut remaining_idx) = unresolved else { + let Some(remaining_idx) = unresolved else { drop(ctx); return self.resolve_variant_on_alias(ty, None, mod_path); }; let mut remaining_segments = path.segments().skip(remaining_idx); + if remaining_segments.len() >= 2 { + path_ctx.ignore_last_segment(); + } + // We need to try resolving unresolved segments one by one because each may resolve // to a projection, which `TyLoweringContext` cannot handle on its own. let mut tried_resolving_once = false; - while !remaining_segments.is_empty() { - let resolved_segment = path.segments().get(remaining_idx - 1).unwrap(); - let current_segment = remaining_segments.take(1); - + while let Some(current_segment) = remaining_segments.first() { // If we can resolve to an enum variant, it takes priority over associated type // of the same name. if let Some((AdtId::EnumId(id), _)) = ty.as_adt() { let enum_data = self.db.enum_data(id); - let name = current_segment.first().unwrap().name; - if let Some(variant) = enum_data.variant(name) { + if let Some(variant) = enum_data.variant(current_segment.name) { return if remaining_segments.len() == 1 { (ty, Some(variant.into())) } else { // We still have unresolved paths, but enum variants never have // associated types! + // FIXME: Report an error. (self.err_ty(), None) }; } @@ -1578,23 +1580,13 @@ impl<'a> InferenceContext<'a> { if tried_resolving_once { // FIXME: with `inherent_associated_types` this is allowed, but our `lower_partly_resolved_path()` // will need to be updated to err at the correct segment. - // - // We need to stop here because otherwise the segment index passed to `lower_partly_resolved_path()` - // will be incorrect, and that can mess up error reporting. break; } // `lower_partly_resolved_path()` returns `None` as type namespace unless // `remaining_segments` is empty, which is never the case here. We don't know // which namespace the new `ty` is in until normalized anyway. - (ty, _) = ctx.lower_partly_resolved_path( - node, - resolution, - resolved_segment, - current_segment, - (remaining_idx - 1) as u32, - false, - ); + (ty, _) = path_ctx.lower_partly_resolved_path(resolution, false); tried_resolving_once = true; ty = self.table.insert_type_vars(ty); @@ -1604,8 +1596,6 @@ impl<'a> InferenceContext<'a> { return (self.err_ty(), None); } - // FIXME(inherent_associated_types): update `resolution` based on `ty` here. - remaining_idx += 1; remaining_segments = remaining_segments.skip(1); } drop(ctx); @@ -1621,12 +1611,7 @@ impl<'a> InferenceContext<'a> { (ty, variant) } TypeNs::TypeAliasId(it) => { - let resolved_seg = match unresolved { - None => path.segments().last().unwrap(), - Some(n) => path.segments().get(path.segments().len() - n - 1).unwrap(), - }; - let substs = - ctx.substs_from_path_segment(resolved_seg, Some(it.into()), true, None); + let substs = path_ctx.substs_from_path_segment(it.into(), true, None); drop(ctx); let ty = self.db.ty(it.into()); let ty = self.insert_type_vars(ty.substitute(Interner, &substs)); diff --git a/crates/hir-ty/src/infer/diagnostics.rs b/crates/hir-ty/src/infer/diagnostics.rs index b85378531ad6..8c0446953a6b 100644 --- a/crates/hir-ty/src/infer/diagnostics.rs +++ b/crates/hir-ty/src/infer/diagnostics.rs @@ -5,16 +5,13 @@ use std::cell::RefCell; use std::ops::{Deref, DerefMut}; -use hir_def::expr_store::HygieneId; -use hir_def::hir::ExprOrPatId; -use hir_def::path::{Path, PathSegment, PathSegments}; -use hir_def::resolver::{ResolveValueResult, Resolver, TypeNs}; -use hir_def::type_ref::TypesMap; -use hir_def::TypeOwnerId; +use either::Either; +use hir_def::{hir::ExprOrPatId, path::Path, resolver::Resolver, type_ref::TypesMap, TypeOwnerId}; -use crate::db::HirDatabase; use crate::{ - InferenceDiagnostic, InferenceTyDiagnosticSource, Ty, TyLoweringContext, TyLoweringDiagnostic, + db::HirDatabase, + lower::path::{PathDiagnosticCallback, PathLoweringContext}, + InferenceDiagnostic, InferenceTyDiagnosticSource, TyLoweringContext, TyLoweringDiagnostic, }; // Unfortunately, this struct needs to use interior mutability (but we encapsulate it) @@ -44,6 +41,11 @@ impl Diagnostics { } } +pub(crate) struct PathDiagnosticCallbackData<'a> { + node: ExprOrPatId, + diagnostics: &'a Diagnostics, +} + pub(super) struct InferenceTyLoweringContext<'a> { ctx: TyLoweringContext<'a>, diagnostics: &'a Diagnostics, @@ -51,6 +53,7 @@ pub(super) struct InferenceTyLoweringContext<'a> { } impl<'a> InferenceTyLoweringContext<'a> { + #[inline] pub(super) fn new( db: &'a dyn HirDatabase, resolver: &'a Resolver, @@ -62,65 +65,42 @@ impl<'a> InferenceTyLoweringContext<'a> { Self { ctx: TyLoweringContext::new(db, resolver, types_map, owner), diagnostics, source } } - pub(super) fn resolve_path_in_type_ns( - &mut self, - path: &Path, - node: ExprOrPatId, - ) -> Option<(TypeNs, Option)> { - let diagnostics = self.diagnostics; - self.ctx.resolve_path_in_type_ns(path, &mut |_, diag| { - diagnostics.push(InferenceDiagnostic::PathDiagnostic { node, diag }) - }) - } - - pub(super) fn resolve_path_in_value_ns( - &mut self, - path: &Path, - node: ExprOrPatId, - hygiene_id: HygieneId, - ) -> Option { - let diagnostics = self.diagnostics; - self.ctx.resolve_path_in_value_ns(path, hygiene_id, &mut |_, diag| { - diagnostics.push(InferenceDiagnostic::PathDiagnostic { node, diag }) - }) - } - - pub(super) fn lower_partly_resolved_path( - &mut self, + #[inline] + pub(super) fn at_path<'b>( + &'b mut self, + path: &'b Path, node: ExprOrPatId, - resolution: TypeNs, - resolved_segment: PathSegment<'_>, - remaining_segments: PathSegments<'_>, - resolved_segment_idx: u32, - infer_args: bool, - ) -> (Ty, Option) { - let diagnostics = self.diagnostics; - self.ctx.lower_partly_resolved_path( - resolution, - resolved_segment, - remaining_segments, - resolved_segment_idx, - infer_args, - &mut |_, diag| diagnostics.push(InferenceDiagnostic::PathDiagnostic { node, diag }), - ) + ) -> PathLoweringContext<'b, 'a> { + let on_diagnostic = PathDiagnosticCallback { + data: Either::Right(PathDiagnosticCallbackData { diagnostics: self.diagnostics, node }), + callback: |data, _, diag| { + let data = data.as_ref().right().unwrap(); + data.diagnostics + .push(InferenceDiagnostic::PathDiagnostic { node: data.node, diag }); + }, + }; + PathLoweringContext::new(&mut self.ctx, on_diagnostic, path) } } impl<'a> Deref for InferenceTyLoweringContext<'a> { type Target = TyLoweringContext<'a>; + #[inline] fn deref(&self) -> &Self::Target { &self.ctx } } impl DerefMut for InferenceTyLoweringContext<'_> { + #[inline] fn deref_mut(&mut self) -> &mut Self::Target { &mut self.ctx } } impl Drop for InferenceTyLoweringContext<'_> { + #[inline] fn drop(&mut self) { self.diagnostics .push_ty_diagnostics(self.source, std::mem::take(&mut self.ctx.diagnostics)); diff --git a/crates/hir-ty/src/infer/expr.rs b/crates/hir-ty/src/infer/expr.rs index 86e5afdb5092..ab3c039ece37 100644 --- a/crates/hir-ty/src/infer/expr.rs +++ b/crates/hir-ty/src/infer/expr.rs @@ -2132,8 +2132,8 @@ impl InferenceContext<'_> { for kind_id in def_generics.iter_self_id().take(self_params) { let arg = args.peek(); let arg = match (kind_id, arg) { - // Lifetimes can be elided. - // Once we have implemented lifetime elision correctly, + // Lifetimes can be inferred. + // Once we have implemented lifetime inference correctly, // this should be handled in a proper way. ( GenericParamId::LifetimeParamId(_), diff --git a/crates/hir-ty/src/infer/pat.rs b/crates/hir-ty/src/infer/pat.rs index 5ff22bea34de..d0fe00ecebdd 100644 --- a/crates/hir-ty/src/infer/pat.rs +++ b/crates/hir-ty/src/infer/pat.rs @@ -564,9 +564,17 @@ impl InferenceContext<'_> { | Pat::Range { .. } | Pat::Slice { .. } => true, Pat::Or(pats) => pats.iter().all(|p| self.is_non_ref_pat(body, *p)), - Pat::Path(p) => { - let v = self.resolve_value_path_inner(p, pat.into()); - v.is_some_and(|x| !matches!(x.0, hir_def::resolver::ValueNs::ConstId(_))) + Pat::Path(path) => { + // A const is a reference pattern, but other value ns things aren't (see #16131). We don't need more than + // the hir-def resolver for this, because if there are segments left, this can only be an (associated) const. + // + // Do not use `TyLoweringContext`'s resolution, we want to ignore errors here (they'll be reported elsewhere). + let resolution = self.resolver.resolve_path_in_value_ns_fully( + self.db.upcast(), + path, + body.pat_path_hygiene(pat), + ); + resolution.is_some_and(|it| !matches!(it, hir_def::resolver::ValueNs::ConstId(_))) } Pat::ConstBlock(..) => false, Pat::Lit(expr) => !matches!( diff --git a/crates/hir-ty/src/infer/path.rs b/crates/hir-ty/src/infer/path.rs index 36ec60a7a2f6..3794912ee980 100644 --- a/crates/hir-ty/src/infer/path.rs +++ b/crates/hir-ty/src/infer/path.rs @@ -7,7 +7,6 @@ use hir_def::{ AdtId, AssocItemId, GenericDefId, ItemContainerId, Lookup, }; use hir_expand::name::Name; -use intern::sym; use stdx::never; use crate::{ @@ -94,7 +93,14 @@ impl InferenceContext<'_> { return Some(ValuePathResolution::NonGeneric(ty)); }; - let substs = self.with_body_ty_lowering(|ctx| ctx.substs_from_path(path, value_def, true)); + let substs = self.with_body_ty_lowering(|ctx| { + let mut path_ctx = ctx.at_path(path, id); + let last_segment = path.segments().len().checked_sub(1); + if let Some(last_segment) = last_segment { + path_ctx.set_current_segment(last_segment) + } + path_ctx.substs_from_path(value_def, true) + }); let substs = substs.as_slice(Interner); if let ValueNs::EnumVariantId(_) = value { @@ -156,15 +162,16 @@ impl InferenceContext<'_> { &self.diagnostics, InferenceTyDiagnosticSource::Body, ); + let mut path_ctx = ctx.at_path(path, id); let (value, self_subst) = if let Some(type_ref) = path.type_anchor() { let last = path.segments().last()?; - let (ty, orig_ns) = ctx.lower_ty_ext(type_ref); + let (ty, orig_ns) = path_ctx.ty_ctx().lower_ty_ext(type_ref); let ty = self.table.insert_type_vars(ty); let ty = self.table.normalize_associated_types_in(ty); - let remaining_segments_for_ty = path.segments().take(path.segments().len() - 1); - let (ty, _) = ctx.lower_ty_relative_path(ty, orig_ns, remaining_segments_for_ty); + path_ctx.ignore_last_segment(); + let (ty, _) = path_ctx.lower_ty_relative_path(ty, orig_ns); drop(ctx); let ty = self.table.insert_type_vars(ty); let ty = self.table.normalize_associated_types_in(ty); @@ -172,14 +179,52 @@ impl InferenceContext<'_> { } else { let hygiene = self.body.expr_or_pat_path_hygiene(id); // FIXME: report error, unresolved first path segment - let value_or_partial = ctx.resolve_path_in_value_ns(path, id, hygiene)?; - drop(ctx); + let value_or_partial = path_ctx.resolve_path_in_value_ns(hygiene)?; match value_or_partial { - ResolveValueResult::ValueNs(it, _) => (it, None), - ResolveValueResult::Partial(def, remaining_index, _) => self - .resolve_assoc_item(id, def, path, remaining_index, id) - .map(|(it, substs)| (it, Some(substs)))?, + ResolveValueResult::ValueNs(it, _) => { + drop(ctx); + (it, None) + } + ResolveValueResult::Partial(def, remaining_index, _) => { + // there may be more intermediate segments between the resolved one and + // the end. Only the last segment needs to be resolved to a value; from + // the segments before that, we need to get either a type or a trait ref. + + let remaining_segments = path.segments().skip(remaining_index); + let is_before_last = remaining_segments.len() == 1; + let last_segment = remaining_segments + .last() + .expect("there should be at least one segment here"); + + let (resolution, substs) = match (def, is_before_last) { + (TypeNs::TraitId(trait_), true) => { + let self_ty = self.table.new_type_var(); + let trait_ref = + path_ctx.lower_trait_ref_from_resolved_path(trait_, self_ty); + drop(ctx); + self.resolve_trait_assoc_item(trait_ref, last_segment, id) + } + (def, _) => { + // Either we already have a type (e.g. `Vec::new`), or we have a + // trait but it's not the last segment, so the next segment + // should resolve to an associated type of that trait (e.g. `::Item::default`) + path_ctx.ignore_last_segment(); + let (ty, _) = path_ctx.lower_partly_resolved_path(def, true); + drop(ctx); + if ty.is_unknown() { + return None; + } + + let ty = self.insert_type_vars(ty); + let ty = self.normalize_associated_types_in(ty); + + self.resolve_ty_assoc_item(ty, last_segment.name, id) + } + }?; + (resolution, Some(substs)) + } } }; Some((value, self_subst)) @@ -212,89 +257,6 @@ impl InferenceContext<'_> { } } - fn resolve_assoc_item( - &mut self, - node: ExprOrPatId, - def: TypeNs, - path: &Path, - remaining_index: usize, - id: ExprOrPatId, - ) -> Option<(ValueNs, Substitution)> { - // there may be more intermediate segments between the resolved one and - // the end. Only the last segment needs to be resolved to a value; from - // the segments before that, we need to get either a type or a trait ref. - - let _d; - let (resolved_segment, remaining_segments) = match path { - Path::Normal { .. } | Path::BarePath(_) => { - assert!(remaining_index < path.segments().len()); - ( - path.segments().get(remaining_index - 1).unwrap(), - path.segments().skip(remaining_index), - ) - } - Path::LangItem(..) => ( - PathSegment { - name: { - _d = Name::new_symbol_root(sym::Unknown.clone()); - &_d - }, - args_and_bindings: None, - }, - path.segments(), - ), - }; - let is_before_last = remaining_segments.len() == 1; - - match (def, is_before_last) { - (TypeNs::TraitId(trait_), true) => { - let segment = - remaining_segments.last().expect("there should be at least one segment here"); - let self_ty = self.table.new_type_var(); - let trait_ref = self.with_body_ty_lowering(|ctx| { - ctx.lower_trait_ref_from_resolved_path(trait_, resolved_segment, self_ty) - }); - self.resolve_trait_assoc_item(trait_ref, segment, id) - } - (def, _) => { - // Either we already have a type (e.g. `Vec::new`), or we have a - // trait but it's not the last segment, so the next segment - // should resolve to an associated type of that trait (e.g. `::Item::default`) - let remaining_segments_for_ty = - remaining_segments.take(remaining_segments.len() - 1); - let mut ctx = TyLoweringContext::new( - self.db, - &self.resolver, - &self.body.types, - self.owner.into(), - &self.diagnostics, - InferenceTyDiagnosticSource::Body, - ); - let (ty, _) = ctx.lower_partly_resolved_path( - node, - def, - resolved_segment, - remaining_segments_for_ty, - (remaining_index - 1) as u32, - true, - ); - drop(ctx); - if ty.is_unknown() { - return None; - } - - let ty = self.insert_type_vars(ty); - let ty = self.normalize_associated_types_in(ty); - - let segment = - remaining_segments.last().expect("there should be at least one segment here"); - - self.resolve_ty_assoc_item(ty, segment.name, id) - } - } - } - fn resolve_trait_assoc_item( &mut self, trait_ref: TraitRef, diff --git a/crates/hir-ty/src/lower.rs b/crates/hir-ty/src/lower.rs index db13e1fd3543..af73b5ed9a7b 100644 --- a/crates/hir-ty/src/lower.rs +++ b/crates/hir-ty/src/lower.rs @@ -6,6 +6,7 @@ //! //! This usually involves resolving names, collecting generic arguments etc. pub(crate) mod diagnostics; +pub(crate) mod path; use std::{ cell::OnceCell, @@ -26,29 +27,26 @@ use hir_def::{ builtin_type::BuiltinType, data::{adt::StructKind, TraitFlags}, expander::Expander, - expr_store::HygieneId, generics::{ GenericParamDataRef, TypeOrConstParamData, TypeParamProvenance, WherePredicate, WherePredicateTypeTarget, }, lang_item::LangItem, nameres::MacroSubNs, - path::{GenericArg, GenericArgs, ModPath, Path, PathKind, PathSegment, PathSegments}, - resolver::{HasResolver, LifetimeNs, ResolveValueResult, Resolver, TypeNs, ValueNs}, + path::{GenericArg, ModPath, Path, PathKind}, + resolver::{HasResolver, LifetimeNs, Resolver, TypeNs}, type_ref::{ ConstRef, LifetimeRef, PathId, TraitBoundModifier, TraitRef as HirTraitRef, TypeBound, TypeRef, TypeRefId, TypesMap, TypesSourceMap, }, AdtId, AssocItemId, CallableDefId, ConstId, ConstParamId, DefWithBodyId, EnumId, EnumVariantId, - FunctionId, GenericDefId, GenericParamId, HasModule, ImplId, InTypeConstLoc, ItemContainerId, - LocalFieldId, Lookup, StaticId, StructId, TraitId, TypeAliasId, TypeOrConstParamId, - TypeOwnerId, UnionId, VariantId, + FunctionId, GenericDefId, GenericParamId, HasModule, ImplId, InTypeConstLoc, LocalFieldId, + Lookup, StaticId, StructId, TypeAliasId, TypeOrConstParamId, TypeOwnerId, UnionId, VariantId, }; use hir_expand::{name::Name, ExpandResult}; use la_arena::{Arena, ArenaMap}; use rustc_hash::FxHashSet; use rustc_pattern_analysis::Captures; -use smallvec::SmallVec; use stdx::{impl_from, never}; use syntax::ast; use triomphe::{Arc, ThinArc}; @@ -62,18 +60,19 @@ use crate::{ db::HirDatabase, error_lifetime, generics::{generics, trait_self_param_idx, Generics}, - lower::diagnostics::*, + lower::{ + diagnostics::*, + path::{PathDiagnosticCallback, PathLoweringContext}, + }, make_binders, mapping::{from_chalk_trait_id, lt_to_placeholder_idx, ToChalk}, - static_lifetime, to_assoc_type_id, to_chalk_trait_id, to_placeholder_idx, - utils::{ - all_super_trait_refs, associated_type_by_name_including_super_traits, InTypeConstIdMetadata, - }, - AliasEq, AliasTy, Binders, BoundVar, CallableSig, Const, ConstScalar, DebruijnIndex, DynTy, - FnAbi, FnPointer, FnSig, FnSubst, ImplTrait, ImplTraitId, ImplTraits, Interner, Lifetime, - LifetimeData, LifetimeOutlives, ParamKind, PolyFnSig, ProgramClause, ProjectionTy, - QuantifiedWhereClause, QuantifiedWhereClauses, Substitution, TraitEnvironment, TraitRef, - TraitRefExt, Ty, TyBuilder, TyKind, WhereClause, + static_lifetime, to_chalk_trait_id, to_placeholder_idx, + utils::{all_super_trait_refs, InTypeConstIdMetadata}, + AliasTy, Binders, BoundVar, CallableSig, Const, ConstScalar, DebruijnIndex, DynTy, FnAbi, + FnPointer, FnSig, FnSubst, ImplTrait, ImplTraitId, ImplTraits, Interner, Lifetime, + LifetimeData, LifetimeOutlives, ParamKind, PolyFnSig, ProgramClause, QuantifiedWhereClause, + QuantifiedWhereClauses, Substitution, TraitEnvironment, TraitRef, TraitRefExt, Ty, TyBuilder, + TyKind, WhereClause, }; #[derive(Debug, Default)] @@ -106,6 +105,8 @@ impl ImplTraitLoweringState { } } +pub(crate) struct PathDiagnosticCallbackData(TypeRefId); + #[derive(Debug)] pub struct TyLoweringContext<'a> { pub db: &'a dyn HirDatabase, @@ -527,9 +528,8 @@ impl<'a> TyLoweringContext<'a> { if path.segments().len() > 1 { return None; } - let resolution = match self - .resolve_path_in_type_ns(path, &mut Self::on_path_diagnostic_callback(type_ref_id)) - { + let mut ctx = self.at_path(PathId::from_type_ref_unchecked(type_ref_id)); + let resolution = match ctx.resolve_path_in_type_ns() { Some((it, None)) => it, _ => return None, }; @@ -539,409 +539,36 @@ impl<'a> TyLoweringContext<'a> { } } - pub(crate) fn lower_ty_relative_path( - &mut self, - ty: Ty, - // We need the original resolution to lower `Self::AssocTy` correctly - res: Option, - remaining_segments: PathSegments<'_>, - ) -> (Ty, Option) { - match remaining_segments.len() { - 0 => (ty, res), - 1 => { - // resolve unselected assoc types - let segment = remaining_segments.first().unwrap(); - (self.select_associated_type(res, segment), None) - } - _ => { - // FIXME report error (ambiguous associated type) - (TyKind::Error.intern(Interner), None) - } - } - } - - pub(crate) fn lower_partly_resolved_path( - &mut self, - resolution: TypeNs, - resolved_segment: PathSegment<'_>, - remaining_segments: PathSegments<'_>, - _resolved_segment_idx: u32, - infer_args: bool, - _on_diagnostic: &mut dyn FnMut(&mut Self, PathLoweringDiagnostic), - ) -> (Ty, Option) { - let ty = match resolution { - TypeNs::TraitId(trait_) => { - let ty = match remaining_segments.len() { - 1 => { - let trait_ref = self.lower_trait_ref_from_resolved_path( - trait_, - resolved_segment, - TyKind::Error.intern(Interner), - ); - let segment = remaining_segments.first().unwrap(); - let found = self - .db - .trait_data(trait_ref.hir_trait_id()) - .associated_type_by_name(segment.name); - - match found { - Some(associated_ty) => { - // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent - // generic params. It's inefficient to splice the `Substitution`s, so we may want - // that method to optionally take parent `Substitution` as we already know them at - // this point (`trait_ref.substitution`). - let substitution = self.substs_from_path_segment( - segment, - Some(associated_ty.into()), - false, - None, - ); - let len_self = - generics(self.db.upcast(), associated_ty.into()).len_self(); - let substitution = Substitution::from_iter( - Interner, - substitution - .iter(Interner) - .take(len_self) - .chain(trait_ref.substitution.iter(Interner)), - ); - TyKind::Alias(AliasTy::Projection(ProjectionTy { - associated_ty_id: to_assoc_type_id(associated_ty), - substitution, - })) - .intern(Interner) - } - None => { - // FIXME: report error (associated type not found) - TyKind::Error.intern(Interner) - } - } - } - 0 => { - // Trait object type without dyn; this should be handled in upstream. See - // `lower_path()`. - stdx::never!("unexpected fully resolved trait path"); - TyKind::Error.intern(Interner) - } - _ => { - // FIXME report error (ambiguous associated type) - TyKind::Error.intern(Interner) - } - }; - return (ty, None); - } - TypeNs::TraitAliasId(_) => { - // FIXME(trait_alias): Implement trait alias. - return (TyKind::Error.intern(Interner), None); - } - TypeNs::GenericParam(param_id) => match self.type_param_mode { - ParamLoweringMode::Placeholder => { - TyKind::Placeholder(to_placeholder_idx(self.db, param_id.into())) - } - ParamLoweringMode::Variable => { - let idx = match self - .generics() - .expect("generics in scope") - .type_or_const_param_idx(param_id.into()) - { - None => { - never!("no matching generics"); - return (TyKind::Error.intern(Interner), None); - } - Some(idx) => idx, - }; - - TyKind::BoundVar(BoundVar::new(self.in_binders, idx)) - } - } - .intern(Interner), - TypeNs::SelfType(impl_id) => { - let generics = self.generics().expect("impl should have generic param scope"); - - match self.type_param_mode { - ParamLoweringMode::Placeholder => { - // `def` can be either impl itself or item within, and we need impl itself - // now. - let generics = generics.parent_or_self(); - let subst = generics.placeholder_subst(self.db); - self.db.impl_self_ty(impl_id).substitute(Interner, &subst) - } - ParamLoweringMode::Variable => { - let starting_from = match generics.def() { - GenericDefId::ImplId(_) => 0, - // `def` is an item within impl. We need to substitute `BoundVar`s but - // remember that they are for parent (i.e. impl) generic params so they - // come after our own params. - _ => generics.len_self(), - }; - TyBuilder::impl_self_ty(self.db, impl_id) - .fill_with_bound_vars(self.in_binders, starting_from) - .build() - } - } - } - TypeNs::AdtSelfType(adt) => { - let generics = generics(self.db.upcast(), adt.into()); - let substs = match self.type_param_mode { - ParamLoweringMode::Placeholder => generics.placeholder_subst(self.db), - ParamLoweringMode::Variable => { - generics.bound_vars_subst(self.db, self.in_binders) - } - }; - self.db.ty(adt.into()).substitute(Interner, &substs) - } - - TypeNs::AdtId(it) => self.lower_path_inner(resolved_segment, it.into(), infer_args), - TypeNs::BuiltinType(it) => { - self.lower_path_inner(resolved_segment, it.into(), infer_args) - } - TypeNs::TypeAliasId(it) => { - self.lower_path_inner(resolved_segment, it.into(), infer_args) - } - // FIXME: report error - TypeNs::EnumVariantId(_) => return (TyKind::Error.intern(Interner), None), - }; - self.lower_ty_relative_path(ty, Some(resolution), remaining_segments) - } - - fn handle_type_ns_resolution( - &mut self, - resolution: &TypeNs, - resolved_segment: PathSegment<'_>, - resolved_segment_idx: usize, - on_diagnostic: &mut dyn FnMut(&mut Self, PathLoweringDiagnostic), - ) { - let mut prohibit_generics_on_resolved = |reason| { - if resolved_segment.args_and_bindings.is_some() { - on_diagnostic( - self, - PathLoweringDiagnostic::GenericArgsProhibited { - segment: resolved_segment_idx as u32, - reason, - }, - ); - } - }; - - match resolution { - TypeNs::SelfType(_) => { - prohibit_generics_on_resolved(GenericArgsProhibitedReason::SelfTy) - } - TypeNs::GenericParam(_) => { - prohibit_generics_on_resolved(GenericArgsProhibitedReason::TyParam) - } - TypeNs::AdtSelfType(_) => { - prohibit_generics_on_resolved(GenericArgsProhibitedReason::SelfTy) - } - TypeNs::BuiltinType(_) => { - prohibit_generics_on_resolved(GenericArgsProhibitedReason::PrimitiveTy) - } - TypeNs::AdtId(_) - | TypeNs::EnumVariantId(_) - | TypeNs::TypeAliasId(_) - | TypeNs::TraitId(_) - | TypeNs::TraitAliasId(_) => {} - } - } - - pub(crate) fn resolve_path_in_type_ns_fully( - &mut self, - path: &Path, - on_diagnostic: &mut dyn FnMut(&mut Self, PathLoweringDiagnostic), - ) -> Option { - let (res, unresolved) = self.resolve_path_in_type_ns(path, on_diagnostic)?; - if unresolved.is_some() { - return None; - } - Some(res) - } - - pub(crate) fn resolve_path_in_type_ns( - &mut self, - path: &Path, - on_diagnostic: &mut dyn FnMut(&mut Self, PathLoweringDiagnostic), - ) -> Option<(TypeNs, Option)> { - let (resolution, remaining_index, _, prefix_info) = - self.resolver.resolve_path_in_type_ns_with_prefix_info(self.db.upcast(), path)?; - let segments = path.segments(); - - match path { - // `segments.is_empty()` can occur with `self`. - Path::Normal(..) if !segments.is_empty() => (), - _ => return Some((resolution, remaining_index)), - }; - - let (module_segments, resolved_segment_idx, enum_segment) = match remaining_index { - None if prefix_info.enum_variant => { - (segments.strip_last_two(), segments.len() - 1, Some(segments.len() - 2)) - } - None => (segments.strip_last(), segments.len() - 1, None), - Some(i) => (segments.take(i - 1), i - 1, None), - }; - - for (i, mod_segment) in module_segments.iter().enumerate() { - if mod_segment.args_and_bindings.is_some() { - on_diagnostic( - self, - PathLoweringDiagnostic::GenericArgsProhibited { - segment: i as u32, - reason: GenericArgsProhibitedReason::Module, - }, - ); - } - } - - if let Some(enum_segment) = enum_segment { - if segments.get(enum_segment).is_some_and(|it| it.args_and_bindings.is_some()) - && segments.get(enum_segment + 1).is_some_and(|it| it.args_and_bindings.is_some()) - { - on_diagnostic( - self, - PathLoweringDiagnostic::GenericArgsProhibited { - segment: (enum_segment + 1) as u32, - reason: GenericArgsProhibitedReason::EnumVariant, - }, - ); - } - } - - self.handle_type_ns_resolution( - &resolution, - segments.get(resolved_segment_idx).expect("should have resolved segment"), - resolved_segment_idx, - on_diagnostic, - ); - - Some((resolution, remaining_index)) - } - - pub(crate) fn resolve_path_in_value_ns( - &mut self, - path: &Path, - hygiene_id: HygieneId, - on_diagnostic: &mut dyn FnMut(&mut Self, PathLoweringDiagnostic), - ) -> Option { - let (res, prefix_info) = self.resolver.resolve_path_in_value_ns_with_prefix_info( - self.db.upcast(), - path, - hygiene_id, - )?; - - let segments = path.segments(); - match path { - // `segments.is_empty()` can occur with `self`. - Path::Normal(..) if !segments.is_empty() => (), - _ => return Some(res), - }; - - let (mod_segments, enum_segment) = match res { - ResolveValueResult::Partial(_, unresolved_segment, _) => { - (segments.take(unresolved_segment - 1), None) - } - ResolveValueResult::ValueNs(ValueNs::EnumVariantId(_), _) - if prefix_info.enum_variant => - { - (segments.strip_last_two(), segments.len().checked_sub(2)) - } - ResolveValueResult::ValueNs(..) => (segments.strip_last(), None), - }; - for (i, mod_segment) in mod_segments.iter().enumerate() { - if mod_segment.args_and_bindings.is_some() { - on_diagnostic( - self, - PathLoweringDiagnostic::GenericArgsProhibited { - segment: i as u32, - reason: GenericArgsProhibitedReason::Module, - }, - ); - } - } - - if let Some(enum_segment) = enum_segment { - if segments.get(enum_segment).is_some_and(|it| it.args_and_bindings.is_some()) - && segments.get(enum_segment + 1).is_some_and(|it| it.args_and_bindings.is_some()) - { - on_diagnostic( - self, - PathLoweringDiagnostic::GenericArgsProhibited { - segment: (enum_segment + 1) as u32, - reason: GenericArgsProhibitedReason::EnumVariant, - }, - ); - } + #[inline] + fn on_path_diagnostic_callback(type_ref: TypeRefId) -> PathDiagnosticCallback<'static> { + PathDiagnosticCallback { + data: Either::Left(PathDiagnosticCallbackData(type_ref)), + callback: |data, this, diag| { + let type_ref = data.as_ref().left().unwrap().0; + this.push_diagnostic(type_ref, TyLoweringDiagnosticKind::PathDiagnostic(diag)) + }, } - - match &res { - ResolveValueResult::ValueNs(resolution, _) => { - let resolved_segment_idx = - segments.len().checked_sub(1).unwrap_or_else(|| panic!("{path:?}")); - let resolved_segment = segments.last().unwrap(); - - let mut prohibit_generics_on_resolved = |reason| { - if resolved_segment.args_and_bindings.is_some() { - on_diagnostic( - self, - PathLoweringDiagnostic::GenericArgsProhibited { - segment: resolved_segment_idx as u32, - reason, - }, - ); - } - }; - - match resolution { - ValueNs::ImplSelf(_) => { - prohibit_generics_on_resolved(GenericArgsProhibitedReason::SelfTy) - } - // FIXME: rustc generates E0107 (incorrect number of generic arguments) and not - // E0109 (generic arguments provided for a type that doesn't accept them) for - // consts and statics, presumably as a defense against future in which consts - // and statics can be generic, or just because it was easier for rustc implementors. - // That means we'll show the wrong error code. Because of us it's easier to do it - // this way :) - ValueNs::GenericParam(_) | ValueNs::ConstId(_) => { - prohibit_generics_on_resolved(GenericArgsProhibitedReason::Const) - } - ValueNs::StaticId(_) => { - prohibit_generics_on_resolved(GenericArgsProhibitedReason::Static) - } - ValueNs::FunctionId(_) | ValueNs::StructId(_) | ValueNs::EnumVariantId(_) => {} - ValueNs::LocalBinding(_) => {} - } - } - ResolveValueResult::Partial(resolution, unresolved_idx, _) => { - let resolved_segment_idx = unresolved_idx - 1; - let resolved_segment = segments.get(resolved_segment_idx).unwrap(); - self.handle_type_ns_resolution( - resolution, - resolved_segment, - resolved_segment_idx, - on_diagnostic, - ); - } - }; - Some(res) } - fn on_path_diagnostic_callback( - type_ref: TypeRefId, - ) -> impl FnMut(&mut Self, PathLoweringDiagnostic) { - move |this, diag| { - this.push_diagnostic(type_ref, TyLoweringDiagnosticKind::PathDiagnostic(diag)) - } + #[inline] + fn at_path(&mut self, path_id: PathId) -> PathLoweringContext<'_, 'a> { + PathLoweringContext::new( + self, + Self::on_path_diagnostic_callback(path_id.type_ref()), + &self.types_map[path_id], + ) } pub(crate) fn lower_path(&mut self, path: &Path, path_id: PathId) -> (Ty, Option) { // Resolve the path (in type namespace) if let Some(type_ref) = path.type_anchor() { let (ty, res) = self.lower_ty_ext(type_ref); - return self.lower_ty_relative_path(ty, res, path.segments()); + let mut ctx = self.at_path(path_id); + return ctx.lower_ty_relative_path(ty, res); } - let (resolution, remaining_index) = match self.resolve_path_in_type_ns( - path, - &mut Self::on_path_diagnostic_callback(path_id.type_ref()), - ) { + let mut ctx = self.at_path(path_id); + let (resolution, remaining_index) = match ctx.resolve_path_in_type_ns() { Some(it) => it, None => return (TyKind::Error.intern(Interner), None), }; @@ -953,354 +580,21 @@ impl<'a> TyLoweringContext<'a> { return (ty, None); } - let (resolved_segment_idx, resolved_segment, remaining_segments) = match remaining_index { - None => ( - path.segments().len() - 1, - path.segments().last().expect("resolved path has at least one element"), - PathSegments::EMPTY, - ), - Some(i) => (i - 1, path.segments().get(i - 1).unwrap(), path.segments().skip(i)), - }; - - self.lower_partly_resolved_path( - resolution, - resolved_segment, - remaining_segments, - resolved_segment_idx as u32, - false, - &mut Self::on_path_diagnostic_callback(path_id.type_ref()), - ) - } - - fn select_associated_type(&mut self, res: Option, segment: PathSegment<'_>) -> Ty { - let Some((generics, res)) = self.generics().zip(res) else { - return TyKind::Error.intern(Interner); - }; - let ty = named_associated_type_shorthand_candidates( - self.db, - generics.def(), - res, - Some(segment.name.clone()), - move |name, t, associated_ty| { - let generics = self.generics().unwrap(); - - if name != segment.name { - return None; - } - - let parent_subst = t.substitution.clone(); - let parent_subst = match self.type_param_mode { - ParamLoweringMode::Placeholder => { - // if we're lowering to placeholders, we have to put them in now. - let s = generics.placeholder_subst(self.db); - s.apply(parent_subst, Interner) - } - ParamLoweringMode::Variable => { - // We need to shift in the bound vars, since - // `named_associated_type_shorthand_candidates` does not do that. - parent_subst.shifted_in_from(Interner, self.in_binders) - } - }; - - // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent - // generic params. It's inefficient to splice the `Substitution`s, so we may want - // that method to optionally take parent `Substitution` as we already know them at - // this point (`t.substitution`). - let substs = - self.substs_from_path_segment(segment, Some(associated_ty.into()), false, None); - - let len_self = - crate::generics::generics(self.db.upcast(), associated_ty.into()).len_self(); - - let substs = Substitution::from_iter( - Interner, - substs.iter(Interner).take(len_self).chain(parent_subst.iter(Interner)), - ); - - Some( - TyKind::Alias(AliasTy::Projection(ProjectionTy { - associated_ty_id: to_assoc_type_id(associated_ty), - substitution: substs, - })) - .intern(Interner), - ) - }, - ); - - ty.unwrap_or_else(|| TyKind::Error.intern(Interner)) - } - - fn lower_path_inner( - &mut self, - segment: PathSegment<'_>, - typeable: TyDefId, - infer_args: bool, - ) -> Ty { - let generic_def = match typeable { - TyDefId::BuiltinType(_) => None, - TyDefId::AdtId(it) => Some(it.into()), - TyDefId::TypeAliasId(it) => Some(it.into()), - }; - let substs = self.substs_from_path_segment(segment, generic_def, infer_args, None); - self.db.ty(typeable).substitute(Interner, &substs) - } - - /// Collect generic arguments from a path into a `Substs`. See also - /// `create_substs_for_ast_path` and `def_to_ty` in rustc. - pub(super) fn substs_from_path( - &mut self, - path: &Path, - // Note that we don't call `db.value_type(resolved)` here, - // `ValueTyDefId` is just a convenient way to pass generics and - // special-case enum variants - resolved: ValueTyDefId, - infer_args: bool, - ) -> Substitution { - let last = path.segments().last(); - let (segment, generic_def) = match resolved { - ValueTyDefId::FunctionId(it) => (last, Some(it.into())), - ValueTyDefId::StructId(it) => (last, Some(it.into())), - ValueTyDefId::UnionId(it) => (last, Some(it.into())), - ValueTyDefId::ConstId(it) => (last, Some(it.into())), - ValueTyDefId::StaticId(_) => (last, None), - ValueTyDefId::EnumVariantId(var) => { - // the generic args for an enum variant may be either specified - // on the segment referring to the enum, or on the segment - // referring to the variant. So `Option::::None` and - // `Option::None::` are both allowed (though the former is - // preferred). See also `def_ids_for_path_segments` in rustc. - let len = path.segments().len(); - let penultimate = len.checked_sub(2).and_then(|idx| path.segments().get(idx)); - let segment = match penultimate { - Some(segment) if segment.args_and_bindings.is_some() => Some(segment), - _ => last, - }; - (segment, Some(var.lookup(self.db.upcast()).parent.into())) - } - }; - if let Some(segment) = segment { - self.substs_from_path_segment(segment, generic_def, infer_args, None) - } else if let Some(generic_def) = generic_def { - // lang item - self.substs_from_args_and_bindings(None, Some(generic_def), infer_args, None) - } else { - Substitution::empty(Interner) - } - } - - pub(super) fn substs_from_path_segment( - &mut self, - segment: PathSegment<'_>, - def: Option, - infer_args: bool, - explicit_self_ty: Option, - ) -> Substitution { - self.substs_from_args_and_bindings( - segment.args_and_bindings, - def, - infer_args, - explicit_self_ty, - ) - } - - fn substs_from_args_and_bindings( - &mut self, - args_and_bindings: Option<&GenericArgs>, - def: Option, - infer_args: bool, - explicit_self_ty: Option, - ) -> Substitution { - let Some(def) = def else { return Substitution::empty(Interner) }; - - // Order is - // - Optional Self parameter - // - Lifetime parameters - // - Type or Const parameters - // - Parent parameters - let def_generics = generics(self.db.upcast(), def); - let ( - parent_params, - self_param, - type_params, - const_params, - impl_trait_params, - lifetime_params, - ) = def_generics.provenance_split(); - let item_len = - self_param as usize + type_params + const_params + impl_trait_params + lifetime_params; - let total_len = parent_params + item_len; - - let mut substs = Vec::new(); - - // we need to iterate the lifetime and type/const params separately as our order of them - // differs from the supplied syntax - - let ty_error = || TyKind::Error.intern(Interner).cast(Interner); - let mut def_toc_iter = def_generics.iter_self_type_or_consts_id(); - let fill_self_param = || { - if self_param { - let self_ty = explicit_self_ty.map(|x| x.cast(Interner)).unwrap_or_else(ty_error); - - if let Some(id) = def_toc_iter.next() { - assert!(matches!(id, GenericParamId::TypeParamId(_))); - substs.push(self_ty); - } - } - }; - let mut had_explicit_args = false; - - if let Some(&GenericArgs { ref args, has_self_type, .. }) = args_and_bindings { - // Fill in the self param first - if has_self_type && self_param { - had_explicit_args = true; - if let Some(id) = def_toc_iter.next() { - assert!(matches!(id, GenericParamId::TypeParamId(_))); - had_explicit_args = true; - if let GenericArg::Type(ty) = &args[0] { - substs.push(self.lower_ty(*ty).cast(Interner)); - } - } - } else { - fill_self_param() - }; - - // Then fill in the supplied lifetime args, or error lifetimes if there are too few - // (default lifetimes aren't a thing) - for arg in args - .iter() - .filter_map(|arg| match arg { - GenericArg::Lifetime(arg) => Some(self.lower_lifetime(arg)), - _ => None, - }) - .chain(iter::repeat(error_lifetime())) - .take(lifetime_params) - { - substs.push(arg.cast(Interner)); - } - - let skip = if has_self_type { 1 } else { 0 }; - // Fill in supplied type and const args - // Note if non-lifetime args are provided, it should be all of them, but we can't rely on that - for (arg, id) in args - .iter() - .filter(|arg| !matches!(arg, GenericArg::Lifetime(_))) - .skip(skip) - .take(type_params + const_params) - .zip(def_toc_iter) - { - had_explicit_args = true; - let arg = generic_arg_to_chalk( - self.db, - id, - arg, - self, - self.types_map, - |this, type_ref| this.lower_ty(type_ref), - |this, const_ref, ty| this.lower_const(const_ref, ty), - |this, lifetime_ref| this.lower_lifetime(lifetime_ref), - ); - substs.push(arg); - } - } else { - fill_self_param(); - } - - let param_to_err = |id| match id { - GenericParamId::ConstParamId(x) => unknown_const_as_generic(self.db.const_param_ty(x)), - GenericParamId::TypeParamId(_) => ty_error(), - GenericParamId::LifetimeParamId(_) => error_lifetime().cast(Interner), - }; - // handle defaults. In expression or pattern path segments without - // explicitly specified type arguments, missing type arguments are inferred - // (i.e. defaults aren't used). - // Generic parameters for associated types are not supposed to have defaults, so we just - // ignore them. - let is_assoc_ty = || match def { - GenericDefId::TypeAliasId(id) => { - matches!(id.lookup(self.db.upcast()).container, ItemContainerId::TraitId(_)) - } - _ => false, - }; - let fill_defaults = (!infer_args || had_explicit_args) && !is_assoc_ty(); - if fill_defaults { - let defaults = &*self.db.generic_defaults(def); - let (item, _parent) = defaults.split_at(item_len); - let parent_from = item_len - substs.len(); - - let mut rem = - def_generics.iter_id().skip(substs.len()).map(param_to_err).collect::>(); - // Fill in defaults for type/const params - for (idx, default_ty) in item[substs.len()..].iter().enumerate() { - // each default can depend on the previous parameters - let substs_so_far = Substitution::from_iter( - Interner, - substs.iter().cloned().chain(rem[idx..].iter().cloned()), - ); - substs.push(default_ty.clone().substitute(Interner, &substs_so_far)); - } - // Fill in remaining parent params - substs.extend(rem.drain(parent_from..)); - } else { - // Fill in remaining def params and parent params - substs.extend(def_generics.iter_id().skip(substs.len()).map(param_to_err)); - } - - assert_eq!(substs.len(), total_len, "expected {} substs, got {}", total_len, substs.len()); - Substitution::from_iter(Interner, substs) - } - - pub(crate) fn lower_trait_ref_from_resolved_path( - &mut self, - resolved: TraitId, - segment: PathSegment<'_>, - explicit_self_ty: Ty, - ) -> TraitRef { - let substs = self.trait_ref_substs_from_path(segment, resolved, explicit_self_ty); - TraitRef { trait_id: to_chalk_trait_id(resolved), substitution: substs } - } - - fn prohibit_generics( - &mut self, - path_id: PathId, - idx: u32, - segments: PathSegments<'_>, - reason: GenericArgsProhibitedReason, - ) { - segments.iter().zip(idx..).for_each(|(segment, idx)| { - if segment.args_and_bindings.is_some() { - self.push_diagnostic( - path_id.type_ref(), - TyLoweringDiagnosticKind::PathDiagnostic( - PathLoweringDiagnostic::GenericArgsProhibited { segment: idx, reason }, - ), - ); - } - }); + ctx.lower_partly_resolved_path(resolution, false) } fn lower_trait_ref_from_path( &mut self, path_id: PathId, explicit_self_ty: Ty, - ) -> Option { - let path = &self.types_map[path_id]; - let resolved = match self.resolve_path_in_type_ns_fully( - path, - &mut Self::on_path_diagnostic_callback(path_id.type_ref()), - )? { + ) -> Option<(TraitRef, PathLoweringContext<'_, 'a>)> { + let mut ctx = self.at_path(path_id); + let resolved = match ctx.resolve_path_in_type_ns_fully()? { // FIXME(trait_alias): We need to handle trait alias here. TypeNs::TraitId(tr) => tr, _ => return None, }; - // Do this after we verify it's indeed a trait to not confuse the user if they're not modules. - self.prohibit_generics( - path_id, - 0, - path.segments().strip_last(), - GenericArgsProhibitedReason::Module, - ); - let segment = path.segments().last().expect("path should have at least one segment"); - Some(self.lower_trait_ref_from_resolved_path(resolved, segment, explicit_self_ty)) + Some((ctx.lower_trait_ref_from_resolved_path(resolved, explicit_self_ty), ctx)) } fn lower_trait_ref( @@ -1308,16 +602,7 @@ impl<'a> TyLoweringContext<'a> { trait_ref: &HirTraitRef, explicit_self_ty: Ty, ) -> Option { - self.lower_trait_ref_from_path(trait_ref.path, explicit_self_ty) - } - - fn trait_ref_substs_from_path( - &mut self, - segment: PathSegment<'_>, - resolved: TraitId, - explicit_self_ty: Ty, - ) -> Substitution { - self.substs_from_path_segment(segment, Some(resolved.into()), false, Some(explicit_self_ty)) + self.lower_trait_ref_from_path(trait_ref.path, explicit_self_ty).map(|it| it.0) } pub(crate) fn lower_where_predicate<'b>( @@ -1365,11 +650,18 @@ impl<'a> TyLoweringContext<'a> { self_ty: Ty, ignore_bindings: bool, ) -> impl Iterator + use<'b, 'a> { - let mut trait_ref = None; - let clause = match bound { - &TypeBound::Path(path, TraitBoundModifier::None) => { - trait_ref = self.lower_trait_ref_from_path(path, self_ty); - trait_ref.clone().map(WhereClause::Implemented).map(crate::wrap_empty_binders) + let mut assoc_bounds = None; + let mut clause = None; + match bound { + &TypeBound::Path(path, TraitBoundModifier::None) | &TypeBound::ForLifetime(_, path) => { + // FIXME Don't silently drop the hrtb lifetimes here + if let Some((trait_ref, ctx)) = self.lower_trait_ref_from_path(path, self_ty) { + if !ignore_bindings { + assoc_bounds = + ctx.assoc_type_bindings_from_type_bound(bound, trait_ref.clone()); + } + clause = Some(crate::wrap_empty_binders(WhereClause::Implemented(trait_ref))); + } } &TypeBound::Path(path, TraitBoundModifier::Maybe) => { let sized_trait = self @@ -1381,170 +673,21 @@ impl<'a> TyLoweringContext<'a> { // If we got another trait here ignore the bound completely. let trait_id = self .lower_trait_ref_from_path(path, self_ty.clone()) - .map(|trait_ref| trait_ref.hir_trait_id()); + .map(|(trait_ref, _)| trait_ref.hir_trait_id()); if trait_id == sized_trait { self.unsized_types.insert(self_ty); } - None - } - &TypeBound::ForLifetime(_, path) => { - // FIXME Don't silently drop the hrtb lifetimes here - trait_ref = self.lower_trait_ref_from_path(path, self_ty); - trait_ref.clone().map(WhereClause::Implemented).map(crate::wrap_empty_binders) } TypeBound::Lifetime(l) => { let lifetime = self.lower_lifetime(l); - Some(crate::wrap_empty_binders(WhereClause::TypeOutlives(TypeOutlives { + clause = Some(crate::wrap_empty_binders(WhereClause::TypeOutlives(TypeOutlives { ty: self_ty, lifetime, - }))) + }))); } - TypeBound::Use(_) | TypeBound::Error => None, - }; - clause.into_iter().chain( - trait_ref - .filter(move |_| !ignore_bindings) - .map(move |tr| self.assoc_type_bindings_from_type_bound(bound, tr)) - .into_iter() - .flatten(), - ) - } - - fn assoc_type_bindings_from_type_bound<'b>( - &'b mut self, - bound: &'b TypeBound, - trait_ref: TraitRef, - ) -> impl Iterator + use<'b, 'a> { - let last_segment = match bound { - &TypeBound::Path(path, TraitBoundModifier::None) | &TypeBound::ForLifetime(_, path) => { - self.types_map[path].segments().last() - } - TypeBound::Path(_, TraitBoundModifier::Maybe) - | TypeBound::Use(_) - | TypeBound::Error - | TypeBound::Lifetime(_) => None, - }; - last_segment - .into_iter() - .filter_map(|segment| segment.args_and_bindings) - .flat_map(|args_and_bindings| args_and_bindings.bindings.iter()) - .flat_map(move |binding| { - let found = associated_type_by_name_including_super_traits( - self.db, - trait_ref.clone(), - &binding.name, - ); - let (super_trait_ref, associated_ty) = match found { - None => return SmallVec::new(), - Some(t) => t, - }; - // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent - // generic params. It's inefficient to splice the `Substitution`s, so we may want - // that method to optionally take parent `Substitution` as we already know them at - // this point (`super_trait_ref.substitution`). - let substitution = self.substs_from_path_segment( - // FIXME: This is hack. We shouldn't really build `PathSegment` directly. - PathSegment { name: &binding.name, args_and_bindings: binding.args.as_ref() }, - Some(associated_ty.into()), - false, // this is not relevant - Some(super_trait_ref.self_type_parameter(Interner)), - ); - let self_params = generics(self.db.upcast(), associated_ty.into()).len_self(); - let substitution = Substitution::from_iter( - Interner, - substitution - .iter(Interner) - .take(self_params) - .chain(super_trait_ref.substitution.iter(Interner)), - ); - let projection_ty = ProjectionTy { - associated_ty_id: to_assoc_type_id(associated_ty), - substitution, - }; - let mut predicates: SmallVec<[_; 1]> = SmallVec::with_capacity( - binding.type_ref.as_ref().map_or(0, |_| 1) + binding.bounds.len(), - ); - if let Some(type_ref) = binding.type_ref { - match (&self.types_map[type_ref], self.impl_trait_mode.mode) { - (TypeRef::ImplTrait(_), ImplTraitLoweringMode::Disallowed) => (), - (_, ImplTraitLoweringMode::Disallowed | ImplTraitLoweringMode::Opaque) => { - let ty = self.lower_ty(type_ref); - let alias_eq = - AliasEq { alias: AliasTy::Projection(projection_ty.clone()), ty }; - predicates - .push(crate::wrap_empty_binders(WhereClause::AliasEq(alias_eq))); - } - (_, ImplTraitLoweringMode::Param | ImplTraitLoweringMode::Variable) => { - // Find the generic index for the target of our `bound` - let target_param_idx = self - .resolver - .where_predicates_in_scope() - .find_map(|(p, _)| match p { - WherePredicate::TypeBound { - target: WherePredicateTypeTarget::TypeOrConstParam(idx), - bound: b, - } if b == bound => Some(idx), - _ => None, - }); - let ty = if let Some(target_param_idx) = target_param_idx { - let mut counter = 0; - let generics = self.generics().expect("generics in scope"); - for (idx, data) in generics.iter_self_type_or_consts() { - // Count the number of `impl Trait` things that appear before - // the target of our `bound`. - // Our counter within `impl_trait_mode` should be that number - // to properly lower each types within `type_ref` - if data.type_param().is_some_and(|p| { - p.provenance == TypeParamProvenance::ArgumentImplTrait - }) { - counter += 1; - } - if idx == *target_param_idx { - break; - } - } - let mut ext = TyLoweringContext::new_maybe_unowned( - self.db, - self.resolver, - self.types_map, - self.types_source_map, - self.owner, - ) - .with_type_param_mode(self.type_param_mode); - match self.impl_trait_mode.mode { - ImplTraitLoweringMode::Param => { - ext.impl_trait_mode = - ImplTraitLoweringState::param(counter); - } - ImplTraitLoweringMode::Variable => { - ext.impl_trait_mode = - ImplTraitLoweringState::variable(counter); - } - _ => unreachable!(), - } - let ty = ext.lower_ty(type_ref); - self.diagnostics.extend(ext.diagnostics); - ty - } else { - self.lower_ty(type_ref) - }; - - let alias_eq = - AliasEq { alias: AliasTy::Projection(projection_ty.clone()), ty }; - predicates - .push(crate::wrap_empty_binders(WhereClause::AliasEq(alias_eq))); - } - } - } - for bound in binding.bounds.iter() { - predicates.extend(self.lower_type_bound( - bound, - TyKind::Alias(AliasTy::Projection(projection_ty.clone())).intern(Interner), - false, - )); - } - predicates - }) + TypeBound::Use(_) | TypeBound::Error => {} + } + clause.into_iter().chain(assoc_bounds.into_iter().flatten()) } fn lower_dyn_trait(&mut self, bounds: &[TypeBound]) -> Ty { diff --git a/crates/hir-ty/src/lower/diagnostics.rs b/crates/hir-ty/src/lower/diagnostics.rs index 7fe196cdbb59..5c77bcd0736a 100644 --- a/crates/hir-ty/src/lower/diagnostics.rs +++ b/crates/hir-ty/src/lower/diagnostics.rs @@ -26,11 +26,11 @@ pub enum GenericArgsProhibitedReason { Static, /// When there is a generic enum, within the expression `Enum::Variant`, /// either `Enum` or `Variant` are allowed to have generic arguments, but not both. - // FIXME: This is not used now but it should be. EnumVariant, } #[derive(Debug, PartialEq, Eq, Clone)] pub enum PathLoweringDiagnostic { GenericArgsProhibited { segment: u32, reason: GenericArgsProhibitedReason }, + ParenthesizedGenericArgsWithoutFnTrait { segment: u32 }, } diff --git a/crates/hir-ty/src/lower/path.rs b/crates/hir-ty/src/lower/path.rs new file mode 100644 index 000000000000..22c5bb9923f0 --- /dev/null +++ b/crates/hir-ty/src/lower/path.rs @@ -0,0 +1,911 @@ +//! A wrapper around [`TyLoweringContext`] specifically for lowering paths. + +use std::iter; + +use chalk_ir::{cast::Cast, fold::Shift, BoundVar}; +use either::Either; +use hir_def::{ + data::TraitFlags, + expr_store::HygieneId, + generics::{TypeParamProvenance, WherePredicate, WherePredicateTypeTarget}, + path::{GenericArg, GenericArgs, Path, PathSegment, PathSegments}, + resolver::{ResolveValueResult, TypeNs, ValueNs}, + type_ref::{TypeBound, TypeRef}, + GenericDefId, GenericParamId, ItemContainerId, Lookup, TraitId, +}; +use smallvec::SmallVec; +use stdx::never; + +use crate::{ + consteval::unknown_const_as_generic, + error_lifetime, + generics::generics, + lower::{ + generic_arg_to_chalk, named_associated_type_shorthand_candidates, ImplTraitLoweringState, + }, + to_assoc_type_id, to_chalk_trait_id, to_placeholder_idx, + utils::associated_type_by_name_including_super_traits, + AliasEq, AliasTy, GenericArgsProhibitedReason, ImplTraitLoweringMode, Interner, + ParamLoweringMode, PathLoweringDiagnostic, ProjectionTy, QuantifiedWhereClause, Substitution, + TraitRef, Ty, TyBuilder, TyDefId, TyKind, TyLoweringContext, ValueTyDefId, WhereClause, +}; + +type CallbackData<'a> = Either< + super::PathDiagnosticCallbackData, + crate::infer::diagnostics::PathDiagnosticCallbackData<'a>, +>; + +// We cannot use `&mut dyn FnMut()` because of lifetime issues, and we don't want to use `Box` +// because of the allocation, so we create a lifetime-less callback, tailored for our needs. +pub(crate) struct PathDiagnosticCallback<'a> { + pub(crate) data: CallbackData<'a>, + pub(crate) callback: fn(&CallbackData<'_>, &mut TyLoweringContext<'_>, PathLoweringDiagnostic), +} + +pub(crate) struct PathLoweringContext<'a, 'b> { + ctx: &'a mut TyLoweringContext<'b>, + on_diagnostic: PathDiagnosticCallback<'a>, + path: &'a Path, + segments: PathSegments<'a>, + current_segment_idx: usize, + /// Contains the previous segment if `current_segment_idx == segments.len()` + current_or_prev_segment: PathSegment<'a>, +} + +impl<'a, 'b> PathLoweringContext<'a, 'b> { + #[inline] + pub(crate) fn new( + ctx: &'a mut TyLoweringContext<'b>, + on_diagnostic: PathDiagnosticCallback<'a>, + path: &'a Path, + ) -> Self { + let segments = path.segments(); + let first_segment = segments.first().unwrap_or(PathSegment::MISSING); + Self { + ctx, + on_diagnostic, + path, + segments, + current_segment_idx: 0, + current_or_prev_segment: first_segment, + } + } + + #[inline] + #[cold] + fn on_diagnostic(&mut self, diag: PathLoweringDiagnostic) { + (self.on_diagnostic.callback)(&self.on_diagnostic.data, self.ctx, diag); + } + + #[inline] + pub(crate) fn ty_ctx(&mut self) -> &mut TyLoweringContext<'b> { + self.ctx + } + + #[inline] + fn current_segment_u32(&self) -> u32 { + self.current_segment_idx as u32 + } + + #[inline] + fn skip_resolved_segment(&mut self) { + if !matches!(self.path, Path::LangItem(..)) { + // In lang items, the resolved "segment" is not one of the segments. Perhaps we should've put it + // point at -1, but I don't feel this is clearer. + self.current_segment_idx += 1; + } + self.update_current_segment(); + } + + #[inline] + fn update_current_segment(&mut self) { + self.current_or_prev_segment = + self.segments.get(self.current_segment_idx).unwrap_or(self.current_or_prev_segment); + } + + #[inline] + pub(crate) fn ignore_last_segment(&mut self) { + self.segments = self.segments.strip_last(); + } + + #[inline] + pub(crate) fn set_current_segment(&mut self, segment: usize) { + self.current_segment_idx = segment; + self.current_or_prev_segment = self + .segments + .get(segment) + .expect("invalid segment passed to PathLoweringContext::set_current_segment()"); + } + + pub(crate) fn lower_ty_relative_path( + &mut self, + ty: Ty, + // We need the original resolution to lower `Self::AssocTy` correctly + res: Option, + ) -> (Ty, Option) { + match self.segments.len() - self.current_segment_idx { + 0 => (ty, res), + 1 => { + // resolve unselected assoc types + (self.select_associated_type(res), None) + } + _ => { + // FIXME report error (ambiguous associated type) + (TyKind::Error.intern(Interner), None) + } + } + } + + fn prohibit_parenthesized_generic_args(&mut self) -> bool { + if let Some(generic_args) = self.current_or_prev_segment.args_and_bindings { + if generic_args.desugared_from_fn { + let segment = self.current_segment_u32(); + self.on_diagnostic( + PathLoweringDiagnostic::ParenthesizedGenericArgsWithoutFnTrait { segment }, + ); + return true; + } + } + false + } + + // When calling this, the current segment is the resolved segment (we don't advance it yet). + pub(crate) fn lower_partly_resolved_path( + &mut self, + resolution: TypeNs, + infer_args: bool, + ) -> (Ty, Option) { + let remaining_segments = self.segments.skip(self.current_segment_idx + 1); + + let ty = match resolution { + TypeNs::TraitId(trait_) => { + let ty = match remaining_segments.len() { + 1 => { + let trait_ref = self.lower_trait_ref_from_resolved_path( + trait_, + TyKind::Error.intern(Interner), + ); + + self.skip_resolved_segment(); + let segment = self.current_or_prev_segment; + let found = + self.ctx.db.trait_data(trait_).associated_type_by_name(segment.name); + + match found { + Some(associated_ty) => { + // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent + // generic params. It's inefficient to splice the `Substitution`s, so we may want + // that method to optionally take parent `Substitution` as we already know them at + // this point (`trait_ref.substitution`). + let substitution = self.substs_from_path_segment( + associated_ty.into(), + false, + None, + ); + let len_self = + generics(self.ctx.db.upcast(), associated_ty.into()).len_self(); + let substitution = Substitution::from_iter( + Interner, + substitution + .iter(Interner) + .take(len_self) + .chain(trait_ref.substitution.iter(Interner)), + ); + TyKind::Alias(AliasTy::Projection(ProjectionTy { + associated_ty_id: to_assoc_type_id(associated_ty), + substitution, + })) + .intern(Interner) + } + None => { + // FIXME: report error (associated type not found) + TyKind::Error.intern(Interner) + } + } + } + 0 => { + // Trait object type without dyn; this should be handled in upstream. See + // `lower_path()`. + stdx::never!("unexpected fully resolved trait path"); + TyKind::Error.intern(Interner) + } + _ => { + // FIXME report error (ambiguous associated type) + TyKind::Error.intern(Interner) + } + }; + return (ty, None); + } + TypeNs::TraitAliasId(_) => { + // FIXME(trait_alias): Implement trait alias. + return (TyKind::Error.intern(Interner), None); + } + TypeNs::GenericParam(param_id) => match self.ctx.type_param_mode { + ParamLoweringMode::Placeholder => { + TyKind::Placeholder(to_placeholder_idx(self.ctx.db, param_id.into())) + } + ParamLoweringMode::Variable => { + let idx = match self + .ctx + .generics() + .expect("generics in scope") + .type_or_const_param_idx(param_id.into()) + { + None => { + never!("no matching generics"); + return (TyKind::Error.intern(Interner), None); + } + Some(idx) => idx, + }; + + TyKind::BoundVar(BoundVar::new(self.ctx.in_binders, idx)) + } + } + .intern(Interner), + TypeNs::SelfType(impl_id) => { + let generics = self.ctx.generics().expect("impl should have generic param scope"); + + match self.ctx.type_param_mode { + ParamLoweringMode::Placeholder => { + // `def` can be either impl itself or item within, and we need impl itself + // now. + let generics = generics.parent_or_self(); + let subst = generics.placeholder_subst(self.ctx.db); + self.ctx.db.impl_self_ty(impl_id).substitute(Interner, &subst) + } + ParamLoweringMode::Variable => { + let starting_from = match generics.def() { + GenericDefId::ImplId(_) => 0, + // `def` is an item within impl. We need to substitute `BoundVar`s but + // remember that they are for parent (i.e. impl) generic params so they + // come after our own params. + _ => generics.len_self(), + }; + TyBuilder::impl_self_ty(self.ctx.db, impl_id) + .fill_with_bound_vars(self.ctx.in_binders, starting_from) + .build() + } + } + } + TypeNs::AdtSelfType(adt) => { + let generics = generics(self.ctx.db.upcast(), adt.into()); + let substs = match self.ctx.type_param_mode { + ParamLoweringMode::Placeholder => generics.placeholder_subst(self.ctx.db), + ParamLoweringMode::Variable => { + generics.bound_vars_subst(self.ctx.db, self.ctx.in_binders) + } + }; + self.ctx.db.ty(adt.into()).substitute(Interner, &substs) + } + + TypeNs::AdtId(it) => self.lower_path_inner(it.into(), infer_args), + TypeNs::BuiltinType(it) => self.lower_path_inner(it.into(), infer_args), + TypeNs::TypeAliasId(it) => self.lower_path_inner(it.into(), infer_args), + // FIXME: report error + TypeNs::EnumVariantId(_) => return (TyKind::Error.intern(Interner), None), + }; + + self.skip_resolved_segment(); + self.lower_ty_relative_path(ty, Some(resolution)) + } + + fn handle_type_ns_resolution(&mut self, resolution: &TypeNs) { + let mut prohibit_generics_on_resolved = |reason| { + if self.current_or_prev_segment.args_and_bindings.is_some() { + let segment = self.current_segment_u32(); + self.on_diagnostic(PathLoweringDiagnostic::GenericArgsProhibited { + segment, + reason, + }); + } + }; + + match resolution { + TypeNs::SelfType(_) => { + prohibit_generics_on_resolved(GenericArgsProhibitedReason::SelfTy) + } + TypeNs::GenericParam(_) => { + prohibit_generics_on_resolved(GenericArgsProhibitedReason::TyParam) + } + TypeNs::AdtSelfType(_) => { + prohibit_generics_on_resolved(GenericArgsProhibitedReason::SelfTy) + } + TypeNs::BuiltinType(_) => { + prohibit_generics_on_resolved(GenericArgsProhibitedReason::PrimitiveTy) + } + TypeNs::AdtId(_) + | TypeNs::EnumVariantId(_) + | TypeNs::TypeAliasId(_) + | TypeNs::TraitId(_) + | TypeNs::TraitAliasId(_) => {} + } + } + + pub(crate) fn resolve_path_in_type_ns_fully(&mut self) -> Option { + let (res, unresolved) = self.resolve_path_in_type_ns()?; + if unresolved.is_some() { + return None; + } + Some(res) + } + + pub(crate) fn resolve_path_in_type_ns(&mut self) -> Option<(TypeNs, Option)> { + let (resolution, remaining_index, _, prefix_info) = self + .ctx + .resolver + .resolve_path_in_type_ns_with_prefix_info(self.ctx.db.upcast(), self.path)?; + + let segments = self.segments; + if segments.is_empty() || matches!(self.path, Path::LangItem(..)) { + // `segments.is_empty()` can occur with `self`. + return Some((resolution, remaining_index)); + } + + let (module_segments, resolved_segment_idx, enum_segment) = match remaining_index { + None if prefix_info.enum_variant => { + (segments.strip_last_two(), segments.len() - 1, Some(segments.len() - 2)) + } + None => (segments.strip_last(), segments.len() - 1, None), + Some(i) => (segments.take(i - 1), i - 1, None), + }; + + self.current_segment_idx = resolved_segment_idx; + self.current_or_prev_segment = + segments.get(resolved_segment_idx).expect("should have resolved segment"); + + if matches!(self.path, Path::BarePath(..)) { + // Bare paths cannot have generics, so skip them as an optimization. + return Some((resolution, remaining_index)); + } + + for (i, mod_segment) in module_segments.iter().enumerate() { + if mod_segment.args_and_bindings.is_some() { + self.on_diagnostic(PathLoweringDiagnostic::GenericArgsProhibited { + segment: i as u32, + reason: GenericArgsProhibitedReason::Module, + }); + } + } + + if let Some(enum_segment) = enum_segment { + if segments.get(enum_segment).is_some_and(|it| it.args_and_bindings.is_some()) + && segments.get(enum_segment + 1).is_some_and(|it| it.args_and_bindings.is_some()) + { + self.on_diagnostic(PathLoweringDiagnostic::GenericArgsProhibited { + segment: (enum_segment + 1) as u32, + reason: GenericArgsProhibitedReason::EnumVariant, + }); + } + } + + self.handle_type_ns_resolution(&resolution); + + Some((resolution, remaining_index)) + } + + pub(crate) fn resolve_path_in_value_ns( + &mut self, + hygiene_id: HygieneId, + ) -> Option { + let (res, prefix_info) = self.ctx.resolver.resolve_path_in_value_ns_with_prefix_info( + self.ctx.db.upcast(), + self.path, + hygiene_id, + )?; + + let segments = self.segments; + if segments.is_empty() || matches!(self.path, Path::LangItem(..)) { + // `segments.is_empty()` can occur with `self`. + return Some(res); + } + + let (mod_segments, enum_segment, resolved_segment_idx) = match res { + ResolveValueResult::Partial(_, unresolved_segment, _) => { + (segments.take(unresolved_segment - 1), None, unresolved_segment - 1) + } + ResolveValueResult::ValueNs(ValueNs::EnumVariantId(_), _) + if prefix_info.enum_variant => + { + (segments.strip_last_two(), segments.len().checked_sub(2), segments.len() - 1) + } + ResolveValueResult::ValueNs(..) => (segments.strip_last(), None, segments.len() - 1), + }; + + self.current_segment_idx = resolved_segment_idx; + self.current_or_prev_segment = + segments.get(resolved_segment_idx).expect("should have resolved segment"); + + for (i, mod_segment) in mod_segments.iter().enumerate() { + if mod_segment.args_and_bindings.is_some() { + self.on_diagnostic(PathLoweringDiagnostic::GenericArgsProhibited { + segment: i as u32, + reason: GenericArgsProhibitedReason::Module, + }); + } + } + + if let Some(enum_segment) = enum_segment { + if segments.get(enum_segment).is_some_and(|it| it.args_and_bindings.is_some()) + && segments.get(enum_segment + 1).is_some_and(|it| it.args_and_bindings.is_some()) + { + self.on_diagnostic(PathLoweringDiagnostic::GenericArgsProhibited { + segment: (enum_segment + 1) as u32, + reason: GenericArgsProhibitedReason::EnumVariant, + }); + } + } + + match &res { + ResolveValueResult::ValueNs(resolution, _) => { + let resolved_segment_idx = self.current_segment_u32(); + let resolved_segment = self.current_or_prev_segment; + + let mut prohibit_generics_on_resolved = |reason| { + if resolved_segment.args_and_bindings.is_some() { + self.on_diagnostic(PathLoweringDiagnostic::GenericArgsProhibited { + segment: resolved_segment_idx, + reason, + }); + } + }; + + match resolution { + ValueNs::ImplSelf(_) => { + prohibit_generics_on_resolved(GenericArgsProhibitedReason::SelfTy) + } + // FIXME: rustc generates E0107 (incorrect number of generic arguments) and not + // E0109 (generic arguments provided for a type that doesn't accept them) for + // consts and statics, presumably as a defense against future in which consts + // and statics can be generic, or just because it was easier for rustc implementors. + // That means we'll show the wrong error code. Because of us it's easier to do it + // this way :) + ValueNs::GenericParam(_) | ValueNs::ConstId(_) => { + prohibit_generics_on_resolved(GenericArgsProhibitedReason::Const) + } + ValueNs::StaticId(_) => { + prohibit_generics_on_resolved(GenericArgsProhibitedReason::Static) + } + ValueNs::FunctionId(_) | ValueNs::StructId(_) | ValueNs::EnumVariantId(_) => {} + ValueNs::LocalBinding(_) => {} + } + } + ResolveValueResult::Partial(resolution, _, _) => { + self.handle_type_ns_resolution(resolution); + } + }; + Some(res) + } + + fn select_associated_type(&mut self, res: Option) -> Ty { + let Some((generics, res)) = self.ctx.generics().zip(res) else { + return TyKind::Error.intern(Interner); + }; + let segment = self.current_or_prev_segment; + let ty = named_associated_type_shorthand_candidates( + self.ctx.db, + generics.def(), + res, + Some(segment.name.clone()), + move |name, t, associated_ty| { + let generics = self.ctx.generics().unwrap(); + + if name != segment.name { + return None; + } + + let parent_subst = t.substitution.clone(); + let parent_subst = match self.ctx.type_param_mode { + ParamLoweringMode::Placeholder => { + // if we're lowering to placeholders, we have to put them in now. + let s = generics.placeholder_subst(self.ctx.db); + s.apply(parent_subst, Interner) + } + ParamLoweringMode::Variable => { + // We need to shift in the bound vars, since + // `named_associated_type_shorthand_candidates` does not do that. + parent_subst.shifted_in_from(Interner, self.ctx.in_binders) + } + }; + + // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent + // generic params. It's inefficient to splice the `Substitution`s, so we may want + // that method to optionally take parent `Substitution` as we already know them at + // this point (`t.substitution`). + let substs = self.substs_from_path_segment(associated_ty.into(), false, None); + + let len_self = + crate::generics::generics(self.ctx.db.upcast(), associated_ty.into()) + .len_self(); + + let substs = Substitution::from_iter( + Interner, + substs.iter(Interner).take(len_self).chain(parent_subst.iter(Interner)), + ); + + Some( + TyKind::Alias(AliasTy::Projection(ProjectionTy { + associated_ty_id: to_assoc_type_id(associated_ty), + substitution: substs, + })) + .intern(Interner), + ) + }, + ); + + ty.unwrap_or_else(|| TyKind::Error.intern(Interner)) + } + + fn lower_path_inner(&mut self, typeable: TyDefId, infer_args: bool) -> Ty { + let generic_def = match typeable { + TyDefId::BuiltinType(builtin) => return TyBuilder::builtin(builtin), + TyDefId::AdtId(it) => it.into(), + TyDefId::TypeAliasId(it) => it.into(), + }; + let substs = self.substs_from_path_segment(generic_def, infer_args, None); + self.ctx.db.ty(typeable).substitute(Interner, &substs) + } + + /// Collect generic arguments from a path into a `Substs`. See also + /// `create_substs_for_ast_path` and `def_to_ty` in rustc. + pub(crate) fn substs_from_path( + &mut self, + // Note that we don't call `db.value_type(resolved)` here, + // `ValueTyDefId` is just a convenient way to pass generics and + // special-case enum variants + resolved: ValueTyDefId, + infer_args: bool, + ) -> Substitution { + let prev_current_segment_idx = self.current_segment_idx; + let prev_current_segment = self.current_or_prev_segment; + + let generic_def = match resolved { + ValueTyDefId::FunctionId(it) => it.into(), + ValueTyDefId::StructId(it) => it.into(), + ValueTyDefId::UnionId(it) => it.into(), + ValueTyDefId::ConstId(it) => it.into(), + ValueTyDefId::StaticId(_) => return Substitution::empty(Interner), + ValueTyDefId::EnumVariantId(var) => { + // the generic args for an enum variant may be either specified + // on the segment referring to the enum, or on the segment + // referring to the variant. So `Option::::None` and + // `Option::None::` are both allowed (though the former is + // FIXME: This isn't strictly correct, enum variants may be used not through the enum + // (via `use Enum::Variant`). The resolver returns whether they were, but we don't have its result + // available here. The worst that can happen is that we will show some confusing diagnostics to the user, + // if generics exist on the module and they don't match with the variant. + // preferred). See also `def_ids_for_path_segments` in rustc. + // + // `wrapping_sub(1)` will return a number which `get` will return None for if current_segment_idx<2. + // This simplifies the code a bit. + let penultimate_idx = self.current_segment_idx.wrapping_sub(1); + let penultimate = self.segments.get(penultimate_idx); + if let Some(penultimate) = penultimate { + if self.current_or_prev_segment.args_and_bindings.is_none() + && penultimate.args_and_bindings.is_some() + { + self.current_segment_idx = penultimate_idx; + self.current_or_prev_segment = penultimate; + } + } + var.lookup(self.ctx.db.upcast()).parent.into() + } + }; + let result = self.substs_from_path_segment(generic_def, infer_args, None); + self.current_segment_idx = prev_current_segment_idx; + self.current_or_prev_segment = prev_current_segment; + result + } + + pub(crate) fn substs_from_path_segment( + &mut self, + def: GenericDefId, + infer_args: bool, + explicit_self_ty: Option, + ) -> Substitution { + let prohibit_parens = match def { + GenericDefId::TraitId(trait_) => { + let trait_data = self.ctx.db.trait_data(trait_); + !trait_data.flags.contains(TraitFlags::RUSTC_PAREN_SUGAR) + } + _ => true, + }; + if prohibit_parens && self.prohibit_parenthesized_generic_args() { + return TyBuilder::unknown_subst(self.ctx.db, def); + } + + self.substs_from_args_and_bindings( + self.current_or_prev_segment.args_and_bindings, + def, + infer_args, + explicit_self_ty, + ) + } + + pub(super) fn substs_from_args_and_bindings( + &mut self, + args_and_bindings: Option<&GenericArgs>, + def: GenericDefId, + infer_args: bool, + explicit_self_ty: Option, + ) -> Substitution { + // Order is + // - Optional Self parameter + // - Lifetime parameters + // - Type or Const parameters + // - Parent parameters + let def_generics = generics(self.ctx.db.upcast(), def); + let ( + parent_params, + self_param, + type_params, + const_params, + impl_trait_params, + lifetime_params, + ) = def_generics.provenance_split(); + let item_len = + self_param as usize + type_params + const_params + impl_trait_params + lifetime_params; + let total_len = parent_params + item_len; + + let mut substs = Vec::new(); + + // we need to iterate the lifetime and type/const params separately as our order of them + // differs from the supplied syntax + + let ty_error = || TyKind::Error.intern(Interner).cast(Interner); + let mut def_toc_iter = def_generics.iter_self_type_or_consts_id(); + let fill_self_param = || { + if self_param { + let self_ty = explicit_self_ty.map(|x| x.cast(Interner)).unwrap_or_else(ty_error); + + if let Some(id) = def_toc_iter.next() { + assert!(matches!(id, GenericParamId::TypeParamId(_))); + substs.push(self_ty); + } + } + }; + let mut had_explicit_args = false; + + if let Some(&GenericArgs { ref args, has_self_type, .. }) = args_and_bindings { + // Fill in the self param first + if has_self_type && self_param { + had_explicit_args = true; + if let Some(id) = def_toc_iter.next() { + assert!(matches!(id, GenericParamId::TypeParamId(_))); + had_explicit_args = true; + if let GenericArg::Type(ty) = &args[0] { + substs.push(self.ctx.lower_ty(*ty).cast(Interner)); + } + } + } else { + fill_self_param() + }; + + // Then fill in the supplied lifetime args, or error lifetimes if there are too few + // (default lifetimes aren't a thing) + for arg in args + .iter() + .filter_map(|arg| match arg { + GenericArg::Lifetime(arg) => Some(self.ctx.lower_lifetime(arg)), + _ => None, + }) + .chain(iter::repeat(error_lifetime())) + .take(lifetime_params) + { + substs.push(arg.cast(Interner)); + } + + let skip = if has_self_type { 1 } else { 0 }; + // Fill in supplied type and const args + // Note if non-lifetime args are provided, it should be all of them, but we can't rely on that + for (arg, id) in args + .iter() + .filter(|arg| !matches!(arg, GenericArg::Lifetime(_))) + .skip(skip) + .take(type_params + const_params) + .zip(def_toc_iter) + { + had_explicit_args = true; + let arg = generic_arg_to_chalk( + self.ctx.db, + id, + arg, + self.ctx, + self.ctx.types_map, + |ctx, type_ref| ctx.lower_ty(type_ref), + |ctx, const_ref, ty| ctx.lower_const(const_ref, ty), + |ctx, lifetime_ref| ctx.lower_lifetime(lifetime_ref), + ); + substs.push(arg); + } + } else { + fill_self_param(); + } + + let param_to_err = |id| match id { + GenericParamId::ConstParamId(x) => { + unknown_const_as_generic(self.ctx.db.const_param_ty(x)) + } + GenericParamId::TypeParamId(_) => ty_error(), + GenericParamId::LifetimeParamId(_) => error_lifetime().cast(Interner), + }; + // handle defaults. In expression or pattern path segments without + // explicitly specified type arguments, missing type arguments are inferred + // (i.e. defaults aren't used). + // Generic parameters for associated types are not supposed to have defaults, so we just + // ignore them. + let is_assoc_ty = || match def { + GenericDefId::TypeAliasId(id) => { + matches!(id.lookup(self.ctx.db.upcast()).container, ItemContainerId::TraitId(_)) + } + _ => false, + }; + let fill_defaults = (!infer_args || had_explicit_args) && !is_assoc_ty(); + if fill_defaults { + let defaults = &*self.ctx.db.generic_defaults(def); + let (item, _parent) = defaults.split_at(item_len); + let parent_from = item_len - substs.len(); + + let mut rem = + def_generics.iter_id().skip(substs.len()).map(param_to_err).collect::>(); + // Fill in defaults for type/const params + for (idx, default_ty) in item[substs.len()..].iter().enumerate() { + // each default can depend on the previous parameters + let substs_so_far = Substitution::from_iter( + Interner, + substs.iter().cloned().chain(rem[idx..].iter().cloned()), + ); + substs.push(default_ty.clone().substitute(Interner, &substs_so_far)); + } + // Fill in remaining parent params + substs.extend(rem.drain(parent_from..)); + } else { + // Fill in remaining def params and parent params + substs.extend(def_generics.iter_id().skip(substs.len()).map(param_to_err)); + } + + assert_eq!(substs.len(), total_len, "expected {} substs, got {}", total_len, substs.len()); + Substitution::from_iter(Interner, substs) + } + + pub(crate) fn lower_trait_ref_from_resolved_path( + &mut self, + resolved: TraitId, + explicit_self_ty: Ty, + ) -> TraitRef { + let substs = self.trait_ref_substs_from_path(resolved, explicit_self_ty); + TraitRef { trait_id: to_chalk_trait_id(resolved), substitution: substs } + } + + fn trait_ref_substs_from_path( + &mut self, + resolved: TraitId, + explicit_self_ty: Ty, + ) -> Substitution { + self.substs_from_path_segment(resolved.into(), false, Some(explicit_self_ty)) + } + + pub(super) fn assoc_type_bindings_from_type_bound<'c>( + mut self, + bound: &'c TypeBound, + trait_ref: TraitRef, + ) -> Option + use<'a, 'b, 'c>> { + self.current_or_prev_segment.args_and_bindings.map(|args_and_bindings| { + args_and_bindings.bindings.iter().flat_map(move |binding| { + let found = associated_type_by_name_including_super_traits( + self.ctx.db, + trait_ref.clone(), + &binding.name, + ); + let (super_trait_ref, associated_ty) = match found { + None => return SmallVec::new(), + Some(t) => t, + }; + // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent + // generic params. It's inefficient to splice the `Substitution`s, so we may want + // that method to optionally take parent `Substitution` as we already know them at + // this point (`super_trait_ref.substitution`). + let substitution = self.substs_from_args_and_bindings( + binding.args.as_ref(), + associated_ty.into(), + false, // this is not relevant + Some(super_trait_ref.self_type_parameter(Interner)), + ); + let self_params = generics(self.ctx.db.upcast(), associated_ty.into()).len_self(); + let substitution = Substitution::from_iter( + Interner, + substitution + .iter(Interner) + .take(self_params) + .chain(super_trait_ref.substitution.iter(Interner)), + ); + let projection_ty = ProjectionTy { + associated_ty_id: to_assoc_type_id(associated_ty), + substitution, + }; + let mut predicates: SmallVec<[_; 1]> = SmallVec::with_capacity( + binding.type_ref.as_ref().map_or(0, |_| 1) + binding.bounds.len(), + ); + if let Some(type_ref) = binding.type_ref { + match (&self.ctx.types_map[type_ref], self.ctx.impl_trait_mode.mode) { + (TypeRef::ImplTrait(_), ImplTraitLoweringMode::Disallowed) => (), + (_, ImplTraitLoweringMode::Disallowed | ImplTraitLoweringMode::Opaque) => { + let ty = self.ctx.lower_ty(type_ref); + let alias_eq = + AliasEq { alias: AliasTy::Projection(projection_ty.clone()), ty }; + predicates + .push(crate::wrap_empty_binders(WhereClause::AliasEq(alias_eq))); + } + (_, ImplTraitLoweringMode::Param | ImplTraitLoweringMode::Variable) => { + // Find the generic index for the target of our `bound` + let target_param_idx = + self.ctx.resolver.where_predicates_in_scope().find_map(|(p, _)| { + match p { + WherePredicate::TypeBound { + target: WherePredicateTypeTarget::TypeOrConstParam(idx), + bound: b, + } if b == bound => Some(idx), + _ => None, + } + }); + let ty = if let Some(target_param_idx) = target_param_idx { + let mut counter = 0; + let generics = self.ctx.generics().expect("generics in scope"); + for (idx, data) in generics.iter_self_type_or_consts() { + // Count the number of `impl Trait` things that appear before + // the target of our `bound`. + // Our counter within `impl_trait_mode` should be that number + // to properly lower each types within `type_ref` + if data.type_param().is_some_and(|p| { + p.provenance == TypeParamProvenance::ArgumentImplTrait + }) { + counter += 1; + } + if idx == *target_param_idx { + break; + } + } + let mut ext = TyLoweringContext::new_maybe_unowned( + self.ctx.db, + self.ctx.resolver, + self.ctx.types_map, + self.ctx.types_source_map, + self.ctx.owner, + ) + .with_type_param_mode(self.ctx.type_param_mode); + match self.ctx.impl_trait_mode.mode { + ImplTraitLoweringMode::Param => { + ext.impl_trait_mode = + ImplTraitLoweringState::param(counter); + } + ImplTraitLoweringMode::Variable => { + ext.impl_trait_mode = + ImplTraitLoweringState::variable(counter); + } + _ => unreachable!(), + } + let ty = ext.lower_ty(type_ref); + self.ctx.diagnostics.extend(ext.diagnostics); + ty + } else { + self.ctx.lower_ty(type_ref) + }; + + let alias_eq = + AliasEq { alias: AliasTy::Projection(projection_ty.clone()), ty }; + predicates + .push(crate::wrap_empty_binders(WhereClause::AliasEq(alias_eq))); + } + } + } + for bound in binding.bounds.iter() { + predicates.extend(self.ctx.lower_type_bound( + bound, + TyKind::Alias(AliasTy::Projection(projection_ty.clone())).intern(Interner), + false, + )); + } + predicates + }) + }) + } +} diff --git a/crates/hir/src/diagnostics.rs b/crates/hir/src/diagnostics.rs index 64e982c42d7f..f6c0bdc6a62c 100644 --- a/crates/hir/src/diagnostics.rs +++ b/crates/hir/src/diagnostics.rs @@ -111,6 +111,7 @@ diagnostics![ UnusedMut, UnusedVariable, GenericArgsProhibited, + ParenthesizedGenericArgsWithoutFnTrait, ]; #[derive(Debug)] @@ -413,6 +414,11 @@ pub struct GenericArgsProhibited { pub reason: GenericArgsProhibitedReason, } +#[derive(Debug)] +pub struct ParenthesizedGenericArgsWithoutFnTrait { + pub args: InFile>, +} + impl AnyDiagnostic { pub(crate) fn body_validation_diagnostic( db: &dyn HirDatabase, @@ -702,8 +708,8 @@ impl AnyDiagnostic { diag: &PathLoweringDiagnostic, path: InFile, ) -> Option { - Some(match diag { - &PathLoweringDiagnostic::GenericArgsProhibited { segment, reason } => { + Some(match *diag { + PathLoweringDiagnostic::GenericArgsProhibited { segment, reason } => { let segment = hir_segment_to_ast_segment(&path.value, segment)?; let args = if let Some(generics) = segment.generic_arg_list() { AstPtr::new(&generics).wrap_left() @@ -713,6 +719,12 @@ impl AnyDiagnostic { let args = path.with_value(args); GenericArgsProhibited { args, reason }.into() } + PathLoweringDiagnostic::ParenthesizedGenericArgsWithoutFnTrait { segment } => { + let segment = hir_segment_to_ast_segment(&path.value, segment)?; + let args = AstPtr::new(&segment.parenthesized_arg_list()?); + let args = path.with_value(args); + ParenthesizedGenericArgsWithoutFnTrait { args }.into() + } }) } diff --git a/crates/ide-diagnostics/src/handlers/parenthesized_generic_args_without_fn_trait.rs b/crates/ide-diagnostics/src/handlers/parenthesized_generic_args_without_fn_trait.rs new file mode 100644 index 000000000000..ccf517234183 --- /dev/null +++ b/crates/ide-diagnostics/src/handlers/parenthesized_generic_args_without_fn_trait.rs @@ -0,0 +1,59 @@ +use crate::{Diagnostic, DiagnosticCode, DiagnosticsContext}; + +// Diagnostic: parenthesized-generic-args-without-fn-trait +// +// This diagnostic is shown when a `Fn`-trait-style generic parameters (`Trait(A, B) -> C`) +// was used on non-`Fn` trait/type. +pub(crate) fn parenthesized_generic_args_without_fn_trait( + ctx: &DiagnosticsContext<'_>, + d: &hir::ParenthesizedGenericArgsWithoutFnTrait, +) -> Diagnostic { + Diagnostic::new_with_syntax_node_ptr( + ctx, + DiagnosticCode::RustcHardError("E0214"), + "parenthesized type parameters may only be used with a `Fn` trait", + d.args.map(Into::into), + ) +} + +#[cfg(test)] +mod tests { + use crate::tests::check_diagnostics; + + #[test] + fn fn_traits_work() { + check_diagnostics( + r#" +//- minicore: async_fn, fn +fn foo< + A: Fn(), + B: FnMut() -> i32, + C: FnOnce(&str, bool), + D: AsyncFn::(u32) -> u32, + E: AsyncFnMut(), + F: AsyncFnOnce() -> bool, +>() {} + "#, + ); + } + + #[test] + fn non_fn_trait() { + check_diagnostics( + r#" +struct Struct(T); +enum Enum { EnumVariant(T) } +type TypeAlias = bool; + +type Foo = TypeAlias() -> bool; + // ^^ error: parenthesized type parameters may only be used with a `Fn` trait + +fn foo(_a: Struct(i32)) { + // ^^^^^ error: parenthesized type parameters may only be used with a `Fn` trait + let _ = ::EnumVariant(0); + // ^^^^^^^ error: parenthesized type parameters may only be used with a `Fn` trait +} + "#, + ); + } +} diff --git a/crates/ide-diagnostics/src/lib.rs b/crates/ide-diagnostics/src/lib.rs index 50c91a69602c..3ea41aa7e859 100644 --- a/crates/ide-diagnostics/src/lib.rs +++ b/crates/ide-diagnostics/src/lib.rs @@ -43,6 +43,7 @@ mod handlers { pub(crate) mod mutability_errors; pub(crate) mod no_such_field; pub(crate) mod non_exhaustive_let; + pub(crate) mod parenthesized_generic_args_without_fn_trait; pub(crate) mod private_assoc_item; pub(crate) mod private_field; pub(crate) mod remove_trailing_return; @@ -466,7 +467,12 @@ pub fn semantic_diagnostics( Some(it) => it, None => continue, }, - AnyDiagnostic::GenericArgsProhibited(d) => handlers::generic_args_prohibited::generic_args_prohibited(&ctx, &d) + AnyDiagnostic::GenericArgsProhibited(d) => { + handlers::generic_args_prohibited::generic_args_prohibited(&ctx, &d) + } + AnyDiagnostic::ParenthesizedGenericArgsWithoutFnTrait(d) => { + handlers::parenthesized_generic_args_without_fn_trait::parenthesized_generic_args_without_fn_trait(&ctx, &d) + } }; res.push(d) } diff --git a/crates/ide/src/syntax_highlighting/test_data/highlight_general.html b/crates/ide/src/syntax_highlighting/test_data/highlight_general.html index 9be7c92fc798..9477d0d1b877 100644 --- a/crates/ide/src/syntax_highlighting/test_data/highlight_general.html +++ b/crates/ide/src/syntax_highlighting/test_data/highlight_general.html @@ -48,17 +48,6 @@ 
use inner::{self as inner_mod};
 mod inner {}
 
-pub mod ops {
-    #[lang = "fn_once"]
-    pub trait FnOnce<Args> {}
-
-    #[lang = "fn_mut"]
-    pub trait FnMut<Args>: FnOnce<Args> {}
-
-    #[lang = "fn"]
-    pub trait Fn<Args>: FnMut<Args> {}
-}
-
 struct Foo {
     x: u32,
 }
@@ -125,8 +114,8 @@
     FOO
 }
 
-use ops::Fn;
-fn baz<F: Fn() -> ()>(f: F) {
+use core::ops::Fn;
+fn baz<F: Fn() -> ()>(f: F) {
     f()
 }
 
diff --git a/crates/ide/src/syntax_highlighting/tests.rs b/crates/ide/src/syntax_highlighting/tests.rs
index b9520ae2bba2..75dc5235625b 100644
--- a/crates/ide/src/syntax_highlighting/tests.rs
+++ b/crates/ide/src/syntax_highlighting/tests.rs
@@ -136,22 +136,11 @@ use self::foo as bar;
 fn test_highlighting() {
     check_highlighting(
         r#"
-//- minicore: derive, copy
+//- minicore: derive, copy, fn
 //- /main.rs crate:main deps:foo
 use inner::{self as inner_mod};
 mod inner {}
 
-pub mod ops {
-    #[lang = "fn_once"]
-    pub trait FnOnce {}
-
-    #[lang = "fn_mut"]
-    pub trait FnMut: FnOnce {}
-
-    #[lang = "fn"]
-    pub trait Fn: FnMut {}
-}
-
 struct Foo {
     x: u32,
 }
@@ -218,7 +207,7 @@ fn const_param() -> usize {
     FOO
 }
 
-use ops::Fn;
+use core::ops::Fn;
 fn baz ()>(f: F) {
     f()
 }
diff --git a/crates/intern/src/symbol/symbols.rs b/crates/intern/src/symbol/symbols.rs
index a53da69d9013..1958e3f7b1d8 100644
--- a/crates/intern/src/symbol/symbols.rs
+++ b/crates/intern/src/symbol/symbols.rs
@@ -13,15 +13,35 @@ use crate::{
 
 macro_rules! define_symbols {
     (@WITH_NAME: $($alias:ident = $value:literal,)* @PLAIN: $($name:ident,)*) => {
-        // Ideally we would be emitting `const` here, but then we no longer have stable addresses
-        // which is what we are relying on for equality! In the future if consts can refer to
-        // statics we should swap these for `const`s and have the string literal being pointed
-        // to be statics to refer to such that their address is stable.
+        // We define symbols as both `const`s and `static`s because some const code requires const symbols,
+        // but code from before the transition relies on the lifetime of the predefined symbols and making them
+        // `const`s make it error (because now they're temporaries). In the future we probably should only
+        // use consts.
+
+        /// Predefined symbols as `const`s (instead of the default `static`s).
+        pub mod consts {
+            use super::{Symbol, TaggedArcPtr};
+
+            // The strings should be in `static`s so that symbol equality holds.
+            $(
+                pub const $name: Symbol = {
+                    static SYMBOL_STR: &str = stringify!($name);
+                    Symbol { repr: TaggedArcPtr::non_arc(&SYMBOL_STR) }
+                };
+            )*
+            $(
+                pub const $alias: Symbol = {
+                    static SYMBOL_STR: &str = $value;
+                    Symbol { repr: TaggedArcPtr::non_arc(&SYMBOL_STR) }
+                };
+            )*
+        }
+
         $(
-            pub static $name: Symbol = Symbol { repr: TaggedArcPtr::non_arc(&stringify!($name)) };
+            pub static $name: Symbol = consts::$name;
         )*
         $(
-            pub static $alias: Symbol = Symbol { repr: TaggedArcPtr::non_arc(&$value) };
+            pub static $alias: Symbol = consts::$alias;
         )*
 
 
@@ -427,6 +447,7 @@ define_symbols! {
     rustc_layout_scalar_valid_range_start,
     rustc_legacy_const_generics,
     rustc_macro_transparency,
+    rustc_paren_sugar,
     rustc_reallocator,
     rustc_reservation_impl,
     rustc_safe_intrinsic,
diff --git a/crates/test-utils/src/minicore.rs b/crates/test-utils/src/minicore.rs
index 4ed68d18e807..202afebde70f 100644
--- a/crates/test-utils/src/minicore.rs
+++ b/crates/test-utils/src/minicore.rs
@@ -647,18 +647,21 @@ pub mod ops {
 
         #[lang = "fn"]
         #[fundamental]
+        #[rustc_paren_sugar]
         pub trait Fn: FnMut {
             extern "rust-call" fn call(&self, args: Args) -> Self::Output;
         }
 
         #[lang = "fn_mut"]
         #[fundamental]
+        #[rustc_paren_sugar]
         pub trait FnMut: FnOnce {
             extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output;
         }
 
         #[lang = "fn_once"]
         #[fundamental]
+        #[rustc_paren_sugar]
         pub trait FnOnce {
             #[lang = "fn_once_output"]
             type Output;
@@ -736,12 +739,14 @@ pub mod ops {
 
         #[lang = "async_fn"]
         #[fundamental]
+        #[rustc_paren_sugar]
         pub trait AsyncFn: AsyncFnMut {
             extern "rust-call" fn async_call(&self, args: Args) -> Self::CallRefFuture<'_>;
         }
 
         #[lang = "async_fn_mut"]
         #[fundamental]
+        #[rustc_paren_sugar]
         pub trait AsyncFnMut: AsyncFnOnce {
             #[lang = "call_ref_future"]
             type CallRefFuture<'a>: Future
@@ -752,6 +757,7 @@ pub mod ops {
 
         #[lang = "async_fn_once"]
         #[fundamental]
+        #[rustc_paren_sugar]
         pub trait AsyncFnOnce {
             #[lang = "async_fn_once_output"]
             type Output;