diff --git a/compiler/rustc_ast_lowering/src/index.rs b/compiler/rustc_ast_lowering/src/index.rs index c506360aa8a..4da09c4ef48 100644 --- a/compiler/rustc_ast_lowering/src/index.rs +++ b/compiler/rustc_ast_lowering/src/index.rs @@ -313,6 +313,13 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> { }); } + fn visit_assoc_type_binding(&mut self, type_binding: &'hir TypeBinding<'hir>) { + self.insert(type_binding.span, type_binding.hir_id, Node::TypeBinding(type_binding)); + self.with_parent(type_binding.hir_id, |this| { + intravisit::walk_assoc_type_binding(this, type_binding) + }) + } + fn visit_trait_item_ref(&mut self, ii: &'hir TraitItemRef) { // Do not visit the duplicate information in TraitItemRef. We want to // map the actual nodes, not the duplicate ones in the *Ref. diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs index cb2e66090e7..01cedccf997 100644 --- a/compiler/rustc_hir/src/hir.rs +++ b/compiler/rustc_hir/src/hir.rs @@ -3302,6 +3302,7 @@ pub enum Node<'hir> { Stmt(&'hir Stmt<'hir>), PathSegment(&'hir PathSegment<'hir>), Ty(&'hir Ty<'hir>), + TypeBinding(&'hir TypeBinding<'hir>), TraitRef(&'hir TraitRef<'hir>), Binding(&'hir Pat<'hir>), Pat(&'hir Pat<'hir>), @@ -3347,6 +3348,7 @@ impl<'hir> Node<'hir> { | Node::PathSegment(PathSegment { ident, .. }) => Some(*ident), Node::Lifetime(lt) => Some(lt.name.ident()), Node::GenericParam(p) => Some(p.name.ident()), + Node::TypeBinding(b) => Some(b.ident), Node::Param(..) | Node::AnonConst(..) | Node::Expr(..) diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs index 4558a3d10c4..fb40008d60b 100644 --- a/compiler/rustc_hir_pretty/src/lib.rs +++ b/compiler/rustc_hir_pretty/src/lib.rs @@ -85,6 +85,7 @@ impl<'a> State<'a> { Node::Stmt(a) => self.print_stmt(&a), Node::PathSegment(a) => self.print_path_segment(&a), Node::Ty(a) => self.print_type(&a), + Node::TypeBinding(a) => self.print_type_binding(&a), Node::TraitRef(a) => self.print_trait_ref(&a), Node::Binding(a) | Node::Pat(a) => self.print_pat(&a), Node::Arm(a) => self.print_arm(&a), @@ -1703,21 +1704,7 @@ impl<'a> State<'a> { for binding in generic_args.bindings.iter() { start_or_comma(self); - self.print_ident(binding.ident); - self.print_generic_args(binding.gen_args, false, false); - self.space(); - match generic_args.bindings[0].kind { - hir::TypeBindingKind::Equality { ref term } => { - self.word_space("="); - match term { - Term::Ty(ref ty) => self.print_type(ty), - Term::Const(ref c) => self.print_anon_const(c), - } - } - hir::TypeBindingKind::Constraint { bounds } => { - self.print_bounds(":", bounds); - } - } + self.print_type_binding(binding); } if !empty.get() { @@ -1726,6 +1713,24 @@ impl<'a> State<'a> { } } + pub fn print_type_binding(&mut self, binding: &hir::TypeBinding<'_>) { + self.print_ident(binding.ident); + self.print_generic_args(binding.gen_args, false, false); + self.space(); + match binding.kind { + hir::TypeBindingKind::Equality { ref term } => { + self.word_space("="); + match term { + Term::Ty(ref ty) => self.print_type(ty), + Term::Const(ref c) => self.print_anon_const(c), + } + } + hir::TypeBindingKind::Constraint { bounds } => { + self.print_bounds(":", bounds); + } + } + } + pub fn print_pat(&mut self, pat: &hir::Pat<'_>) { self.maybe_print_comment(pat.span.lo()); self.ann.pre(self, AnnNode::Pat(pat)); diff --git a/compiler/rustc_middle/src/hir/map/mod.rs b/compiler/rustc_middle/src/hir/map/mod.rs index 779af7a3827..ebda9f7588d 100644 --- a/compiler/rustc_middle/src/hir/map/mod.rs +++ b/compiler/rustc_middle/src/hir/map/mod.rs @@ -298,6 +298,7 @@ impl<'hir> Map<'hir> { Node::Stmt(_) | Node::PathSegment(_) | Node::Ty(_) + | Node::TypeBinding(_) | Node::Infer(_) | Node::TraitRef(_) | Node::Pat(_) @@ -323,7 +324,8 @@ impl<'hir> Map<'hir> { } pub fn get_parent_node(self, hir_id: HirId) -> HirId { - self.find_parent_node(hir_id).unwrap() + self.find_parent_node(hir_id) + .unwrap_or_else(|| bug!("No parent for node {:?}", self.node_to_string(hir_id))) } /// Retrieves the `Node` corresponding to `id`, returning `None` if cannot be found. @@ -973,6 +975,7 @@ impl<'hir> Map<'hir> { .with_hi(seg.args.map_or_else(|| ident_span.hi(), |args| args.span_ext.hi())) } Node::Ty(ty) => ty.span, + Node::TypeBinding(tb) => tb.span, Node::TraitRef(tr) => tr.path.span, Node::Binding(pat) => pat.span, Node::Pat(pat) => pat.span, @@ -1205,6 +1208,7 @@ fn hir_id_to_string(map: Map<'_>, id: HirId) -> String { Some(Node::Stmt(_)) => node_str("stmt"), Some(Node::PathSegment(_)) => node_str("path segment"), Some(Node::Ty(_)) => node_str("type"), + Some(Node::TypeBinding(_)) => node_str("type binding"), Some(Node::TraitRef(_)) => node_str("trait ref"), Some(Node::Binding(_)) => node_str("local"), Some(Node::Pat(_)) => node_str("pat"), diff --git a/compiler/rustc_middle/src/middle/resolve_lifetime.rs b/compiler/rustc_middle/src/middle/resolve_lifetime.rs index cdc0d076801..7d0b751d35a 100644 --- a/compiler/rustc_middle/src/middle/resolve_lifetime.rs +++ b/compiler/rustc_middle/src/middle/resolve_lifetime.rs @@ -23,8 +23,7 @@ pub enum Region { pub enum LifetimeScopeForPath { /// Contains all lifetime names that are in scope and could possibly be used in generics /// arguments of path. - NonElided(Vec), - + NonElided, /// Information that allows us to suggest args of the form `<'_>` in case /// no generic arguments were provided for a path. Elided, diff --git a/compiler/rustc_resolve/src/late/lifetimes.rs b/compiler/rustc_resolve/src/late/lifetimes.rs index 11f80b314d7..50e067e225f 100644 --- a/compiler/rustc_resolve/src/late/lifetimes.rs +++ b/compiler/rustc_resolve/src/late/lifetimes.rs @@ -517,30 +517,16 @@ fn late_region_as_bound_region<'tcx>(tcx: TyCtxt<'tcx>, region: &Region) -> ty:: #[tracing::instrument(level = "debug")] fn get_lifetime_scopes_for_path(mut scope: &Scope<'_>) -> LifetimeScopeForPath { - let mut available_lifetimes = vec![]; loop { match scope { - Scope::Binder { lifetimes, s, .. } => { - available_lifetimes.extend(lifetimes.keys()); - scope = s; - } - Scope::Body { s, .. } => { - scope = s; - } - Scope::Elision { elide, s } => { - if let Elide::Exact(_) = elide { - return LifetimeScopeForPath::Elided; - } else { - scope = s; - } - } - Scope::ObjectLifetimeDefault { s, .. } => { - scope = s; - } - Scope::Root => { - return LifetimeScopeForPath::NonElided(available_lifetimes); - } - Scope::Supertrait { s, .. } | Scope::TraitRefBoundary { s, .. } => { + Scope::Elision { elide: Elide::Exact(_), .. } => return LifetimeScopeForPath::Elided, + Scope::Root => return LifetimeScopeForPath::NonElided, + Scope::Binder { s, .. } + | Scope::Body { s, .. } + | Scope::ObjectLifetimeDefault { s, .. } + | Scope::Supertrait { s, .. } + | Scope::TraitRefBoundary { s, .. } + | Scope::Elision { s, .. } => { scope = s; } } @@ -2170,6 +2156,9 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> { // Foreign functions, `fn(...) -> R` and `Trait(...) -> R` (both types and bounds). Node::ForeignItem(_) | Node::Ty(_) | Node::TraitRef(_) => None, + + Node::TypeBinding(_) if let Node::TraitRef(_) = self.tcx.hir().get(self.tcx.hir().get_parent_node(parent)) => None, + // Everything else (only closures?) doesn't // actually enjoy elision in return types. _ => { diff --git a/compiler/rustc_typeck/src/check/generator_interior/drop_ranges/cfg_build.rs b/compiler/rustc_typeck/src/check/generator_interior/drop_ranges/cfg_build.rs index 417778cc57d..58b63804b4a 100644 --- a/compiler/rustc_typeck/src/check/generator_interior/drop_ranges/cfg_build.rs +++ b/compiler/rustc_typeck/src/check/generator_interior/drop_ranges/cfg_build.rs @@ -249,6 +249,7 @@ impl<'a, 'tcx> DropRangeVisitor<'a, 'tcx> { | hir::Node::Stmt(..) | hir::Node::PathSegment(..) | hir::Node::Ty(..) + | hir::Node::TypeBinding(..) | hir::Node::TraitRef(..) | hir::Node::Binding(..) | hir::Node::Pat(..) diff --git a/compiler/rustc_typeck/src/collect/type_of.rs b/compiler/rustc_typeck/src/collect/type_of.rs index 7e3fefe4502..2433401b7f0 100644 --- a/compiler/rustc_typeck/src/collect/type_of.rs +++ b/compiler/rustc_typeck/src/collect/type_of.rs @@ -450,21 +450,10 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> { .discr_type() .to_ty(tcx), - Node::TraitRef(trait_ref @ &TraitRef { - path, .. - }) if let Some((binding, seg)) = - path - .segments - .iter() - .find_map(|seg| { - seg.args?.bindings - .iter() - .find_map(|binding| if binding.opt_const()?.hir_id == hir_id { - Some((binding, seg)) - } else { - None - }) - }) => + Node::TypeBinding(binding @ &TypeBinding { hir_id: binding_id, .. }) + if let Node::TraitRef(trait_ref) = tcx.hir().get( + tcx.hir().get_parent_node(binding_id) + ) => { let Some(trait_def_id) = trait_ref.trait_def_id() else { return tcx.ty_error_with_message(DUMMY_SP, "Could not find trait"); diff --git a/compiler/rustc_typeck/src/structured_errors/wrong_number_of_generic_args.rs b/compiler/rustc_typeck/src/structured_errors/wrong_number_of_generic_args.rs index bc3a3db9fda..c433c5ebbd3 100644 --- a/compiler/rustc_typeck/src/structured_errors/wrong_number_of_generic_args.rs +++ b/compiler/rustc_typeck/src/structured_errors/wrong_number_of_generic_args.rs @@ -291,7 +291,52 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> { } // Creates lifetime name suggestions from the lifetime parameter names - fn get_lifetime_args_suggestions_from_param_names(&self, num_params_to_take: usize) -> String { + fn get_lifetime_args_suggestions_from_param_names( + &self, + path_hir_id: Option, + num_params_to_take: usize, + ) -> String { + debug!(?path_hir_id); + + if let Some(path_hir_id) = path_hir_id { + // We first try to get lifetime name suggestions from scope or elision information. + // If none is available we use the parameter definitions + if let Some(LifetimeScopeForPath::Elided) = self.tcx.lifetime_scope(path_hir_id) { + // Use suggestions of the form `<'_, '_>` in case lifetime can be elided + return ["'_"].repeat(num_params_to_take).join(","); + } + + let mut ret = Vec::new(); + for (id, node) in self.tcx.hir().parent_iter(path_hir_id) { + debug!(?id); + let params = if let Some(generics) = node.generics() { + generics.params + } else if let hir::Node::Ty(ty) = node + && let hir::TyKind::BareFn(bare_fn) = ty.kind + { + bare_fn.generic_params + } else { + &[] + }; + ret.extend(params.iter().filter_map(|p| { + let hir::GenericParamKind::Lifetime { kind: hir::LifetimeParamKind::Explicit } + = p.kind + else { return None }; + let hir::ParamName::Plain(name) = p.name else { return None }; + Some(name.to_string()) + })); + if ret.len() >= num_params_to_take { + return ret[..num_params_to_take].join(", "); + } + // We cannot refer to lifetimes defined in an outer function. + if let hir::Node::Item(_) = node { + break; + } + } + } + + // We could not gather enough lifetime parameters in the scope. + // We use the parameter names from the target type's definition instead. self.gen_params .params .iter() @@ -501,44 +546,10 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> { let num_params_to_take = num_missing_args; let msg = format!("add missing {} argument{}", self.kind(), pluralize!(num_missing_args)); - // we first try to get lifetime name suggestions from scope or elision information. If none is - // available we use the parameter definitions - let suggested_args = if let Some(hir_id) = self.path_segment.hir_id { - if let Some(lifetimes_in_scope) = self.tcx.lifetime_scope(hir_id) { - match lifetimes_in_scope { - LifetimeScopeForPath::NonElided(param_names) => { - debug!("NonElided(param_names: {:?})", param_names); - - if param_names.len() >= num_params_to_take { - // use lifetime parameters in scope for suggestions - param_names - .iter() - .take(num_params_to_take) - .map(|def_id| { - self.tcx.item_name(def_id.to_def_id()).to_ident_string() - }) - .collect::>() - .join(", ") - } else { - // Not enough lifetime arguments in scope -> create suggestions from - // lifetime parameter names in definition. An error for the incorrect - // lifetime scope will be output later. - self.get_lifetime_args_suggestions_from_param_names(num_params_to_take) - } - } - LifetimeScopeForPath::Elided => { - debug!("Elided"); - // use suggestions of the form `<'_, '_>` in case lifetime can be elided - ["'_"].repeat(num_params_to_take).join(",") - } - } - } else { - self.get_lifetime_args_suggestions_from_param_names(num_params_to_take) - } - } else { - self.get_lifetime_args_suggestions_from_param_names(num_params_to_take) - }; - + let suggested_args = self.get_lifetime_args_suggestions_from_param_names( + self.path_segment.hir_id, + num_params_to_take, + ); debug!("suggested_args: {:?}", &suggested_args); match self.angle_brackets {