diff options
Diffstat (limited to 'compiler/rustc_hir_analysis/src/astconv')
| -rw-r--r-- | compiler/rustc_hir_analysis/src/astconv/errors.rs | 4 | ||||
| -rw-r--r-- | compiler/rustc_hir_analysis/src/astconv/generics.rs | 1134 | ||||
| -rw-r--r-- | compiler/rustc_hir_analysis/src/astconv/mod.rs | 458 |
3 files changed, 883 insertions, 713 deletions
diff --git a/compiler/rustc_hir_analysis/src/astconv/errors.rs b/compiler/rustc_hir_analysis/src/astconv/errors.rs index e6465d641..232ef2079 100644 --- a/compiler/rustc_hir_analysis/src/astconv/errors.rs +++ b/compiler/rustc_hir_analysis/src/astconv/errors.rs @@ -267,7 +267,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // segments, even though `trait_ref.path.segments` is of length `1`. Work // around that bug here, even though it should be fixed elsewhere. // This would otherwise cause an invalid suggestion. For an example, look at - // `src/test/ui/issues/issue-28344.rs` where instead of the following: + // `tests/ui/issues/issue-28344.rs` where instead of the following: // // error[E0191]: the value of the associated type `Output` // (from trait `std::ops::BitXor`) must be specified @@ -331,7 +331,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } if potential_assoc_types.len() == assoc_items.len() { // When the amount of missing associated types equals the number of - // extra type arguments present. A suggesting to replace the generic args with + // extra type arguments present. A suggesting to replace the generic args with // associated types is already emitted. already_has_generics_args_suggestion = true; } else if let (Ok(snippet), false) = diff --git a/compiler/rustc_hir_analysis/src/astconv/generics.rs b/compiler/rustc_hir_analysis/src/astconv/generics.rs index f64d65cc6..7a499327d 100644 --- a/compiler/rustc_hir_analysis/src/astconv/generics.rs +++ b/compiler/rustc_hir_analysis/src/astconv/generics.rs @@ -1,6 +1,6 @@ use super::IsMethodCall; use crate::astconv::{ - AstConv, CreateSubstsForGenericArgsCtxt, ExplicitLateBound, GenericArgCountMismatch, + CreateSubstsForGenericArgsCtxt, ExplicitLateBound, GenericArgCountMismatch, GenericArgCountResult, GenericArgPosition, }; use crate::errors::AssocTypeBindingNotAllowed; @@ -18,642 +18,624 @@ use rustc_session::lint::builtin::LATE_BOUND_LIFETIME_ARGUMENTS; use rustc_span::{symbol::kw, Span}; use smallvec::SmallVec; -impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { - /// Report an error that a generic argument did not match the generic parameter that was - /// expected. - fn generic_arg_mismatch_err( - tcx: TyCtxt<'_>, - arg: &GenericArg<'_>, - param: &GenericParamDef, - possible_ordering_error: bool, - help: Option<&str>, - ) { - let sess = tcx.sess; - let mut err = struct_span_err!( - sess, - arg.span(), - E0747, - "{} provided when a {} was expected", - arg.descr(), - param.kind.descr(), - ); - - if let GenericParamDefKind::Const { .. } = param.kind { - if matches!(arg, GenericArg::Type(hir::Ty { kind: hir::TyKind::Infer, .. })) { - err.help("const arguments cannot yet be inferred with `_`"); - if sess.is_nightly_build() { - err.help( - "add `#![feature(generic_arg_infer)]` to the crate attributes to enable", - ); - } +/// Report an error that a generic argument did not match the generic parameter that was +/// expected. +fn generic_arg_mismatch_err( + tcx: TyCtxt<'_>, + arg: &GenericArg<'_>, + param: &GenericParamDef, + possible_ordering_error: bool, + help: Option<&str>, +) { + let sess = tcx.sess; + let mut err = struct_span_err!( + sess, + arg.span(), + E0747, + "{} provided when a {} was expected", + arg.descr(), + param.kind.descr(), + ); + + if let GenericParamDefKind::Const { .. } = param.kind { + if matches!(arg, GenericArg::Type(hir::Ty { kind: hir::TyKind::Infer, .. })) { + err.help("const arguments cannot yet be inferred with `_`"); + if sess.is_nightly_build() { + err.help("add `#![feature(generic_arg_infer)]` to the crate attributes to enable"); } } + } - let add_braces_suggestion = |arg: &GenericArg<'_>, err: &mut Diagnostic| { - let suggestions = vec![ - (arg.span().shrink_to_lo(), String::from("{ ")), - (arg.span().shrink_to_hi(), String::from(" }")), - ]; - err.multipart_suggestion( - "if this generic argument was intended as a const parameter, \ + let add_braces_suggestion = |arg: &GenericArg<'_>, err: &mut Diagnostic| { + let suggestions = vec![ + (arg.span().shrink_to_lo(), String::from("{ ")), + (arg.span().shrink_to_hi(), String::from(" }")), + ]; + err.multipart_suggestion( + "if this generic argument was intended as a const parameter, \ surround it with braces", - suggestions, - Applicability::MaybeIncorrect, - ); - }; - - // Specific suggestion set for diagnostics - match (arg, ¶m.kind) { - ( - GenericArg::Type(hir::Ty { - kind: hir::TyKind::Path(rustc_hir::QPath::Resolved(_, path)), - .. - }), - GenericParamDefKind::Const { .. }, - ) => match path.res { - Res::Err => { - add_braces_suggestion(arg, &mut err); - err.set_primary_message( - "unresolved item provided when a constant was expected", - ) + suggestions, + Applicability::MaybeIncorrect, + ); + }; + + // Specific suggestion set for diagnostics + match (arg, ¶m.kind) { + ( + GenericArg::Type(hir::Ty { + kind: hir::TyKind::Path(rustc_hir::QPath::Resolved(_, path)), + .. + }), + GenericParamDefKind::Const { .. }, + ) => match path.res { + Res::Err => { + add_braces_suggestion(arg, &mut err); + err.set_primary_message("unresolved item provided when a constant was expected") .emit(); - return; - } - Res::Def(DefKind::TyParam, src_def_id) => { - if let Some(param_local_id) = param.def_id.as_local() { - let param_name = tcx.hir().ty_param_name(param_local_id); - let param_type = tcx.type_of(param.def_id); - if param_type.is_suggestable(tcx, false) { - err.span_suggestion( - tcx.def_span(src_def_id), - "consider changing this type parameter to be a `const` generic", - format!("const {}: {}", param_name, param_type), - Applicability::MaybeIncorrect, - ); - }; - } - } - _ => add_braces_suggestion(arg, &mut err), - }, - ( - GenericArg::Type(hir::Ty { kind: hir::TyKind::Path(_), .. }), - GenericParamDefKind::Const { .. }, - ) => add_braces_suggestion(arg, &mut err), - ( - GenericArg::Type(hir::Ty { kind: hir::TyKind::Array(_, len), .. }), - GenericParamDefKind::Const { .. }, - ) if tcx.type_of(param.def_id) == tcx.types.usize => { - let snippet = sess.source_map().span_to_snippet(tcx.hir().span(len.hir_id())); - if let Ok(snippet) = snippet { - err.span_suggestion( - arg.span(), - "array type provided where a `usize` was expected, try", - format!("{{ {} }}", snippet), - Applicability::MaybeIncorrect, - ); + return; + } + Res::Def(DefKind::TyParam, src_def_id) => { + if let Some(param_local_id) = param.def_id.as_local() { + let param_name = tcx.hir().ty_param_name(param_local_id); + let param_type = tcx.type_of(param.def_id); + if param_type.is_suggestable(tcx, false) { + err.span_suggestion( + tcx.def_span(src_def_id), + "consider changing this type parameter to be a `const` generic", + format!("const {}: {}", param_name, param_type), + Applicability::MaybeIncorrect, + ); + }; } } - (GenericArg::Const(cnst), GenericParamDefKind::Type { .. }) => { - let body = tcx.hir().body(cnst.value.body); - if let rustc_hir::ExprKind::Path(rustc_hir::QPath::Resolved(_, path)) = - body.value.kind - { - if let Res::Def(DefKind::Fn { .. }, id) = path.res { - err.help(&format!( - "`{}` is a function item, not a type", - tcx.item_name(id) - )); - err.help("function item types cannot be named directly"); - } + _ => add_braces_suggestion(arg, &mut err), + }, + ( + GenericArg::Type(hir::Ty { kind: hir::TyKind::Path(_), .. }), + GenericParamDefKind::Const { .. }, + ) => add_braces_suggestion(arg, &mut err), + ( + GenericArg::Type(hir::Ty { kind: hir::TyKind::Array(_, len), .. }), + GenericParamDefKind::Const { .. }, + ) if tcx.type_of(param.def_id) == tcx.types.usize => { + let snippet = sess.source_map().span_to_snippet(tcx.hir().span(len.hir_id())); + if let Ok(snippet) = snippet { + err.span_suggestion( + arg.span(), + "array type provided where a `usize` was expected, try", + format!("{{ {} }}", snippet), + Applicability::MaybeIncorrect, + ); + } + } + (GenericArg::Const(cnst), GenericParamDefKind::Type { .. }) => { + let body = tcx.hir().body(cnst.value.body); + if let rustc_hir::ExprKind::Path(rustc_hir::QPath::Resolved(_, path)) = body.value.kind + { + if let Res::Def(DefKind::Fn { .. }, id) = path.res { + err.help(&format!("`{}` is a function item, not a type", tcx.item_name(id))); + err.help("function item types cannot be named directly"); } } - _ => {} } + _ => {} + } - let kind_ord = param.kind.to_ord(); - let arg_ord = arg.to_ord(); + let kind_ord = param.kind.to_ord(); + let arg_ord = arg.to_ord(); - // This note is only true when generic parameters are strictly ordered by their kind. - if possible_ordering_error && kind_ord.cmp(&arg_ord) != core::cmp::Ordering::Equal { - let (first, last) = if kind_ord < arg_ord { - (param.kind.descr(), arg.descr()) - } else { - (arg.descr(), param.kind.descr()) - }; - err.note(&format!("{} arguments must be provided before {} arguments", first, last)); - if let Some(help) = help { - err.help(help); - } + // This note is only true when generic parameters are strictly ordered by their kind. + if possible_ordering_error && kind_ord.cmp(&arg_ord) != core::cmp::Ordering::Equal { + let (first, last) = if kind_ord < arg_ord { + (param.kind.descr(), arg.descr()) + } else { + (arg.descr(), param.kind.descr()) + }; + err.note(&format!("{} arguments must be provided before {} arguments", first, last)); + if let Some(help) = help { + err.help(help); } + } + + err.emit(); +} - err.emit(); +/// Creates the relevant generic argument substitutions +/// corresponding to a set of generic parameters. This is a +/// rather complex function. Let us try to explain the role +/// of each of its parameters: +/// +/// To start, we are given the `def_id` of the thing we are +/// creating the substitutions for, and a partial set of +/// substitutions `parent_substs`. In general, the substitutions +/// for an item begin with substitutions for all the "parents" of +/// that item -- e.g., for a method it might include the +/// parameters from the impl. +/// +/// Therefore, the method begins by walking down these parents, +/// starting with the outermost parent and proceed inwards until +/// it reaches `def_id`. For each parent `P`, it will check `parent_substs` +/// first to see if the parent's substitutions are listed in there. If so, +/// we can append those and move on. Otherwise, it invokes the +/// three callback functions: +/// +/// - `args_for_def_id`: given the `DefId` `P`, supplies back the +/// generic arguments that were given to that parent from within +/// the path; so e.g., if you have `<T as Foo>::Bar`, the `DefId` +/// might refer to the trait `Foo`, and the arguments might be +/// `[T]`. The boolean value indicates whether to infer values +/// for arguments whose values were not explicitly provided. +/// - `provided_kind`: given the generic parameter and the value from `args_for_def_id`, +/// instantiate a `GenericArg`. +/// - `inferred_kind`: if no parameter was provided, and inference is enabled, then +/// creates a suitable inference variable. +pub fn create_substs_for_generic_args<'tcx, 'a>( + tcx: TyCtxt<'tcx>, + def_id: DefId, + parent_substs: &[subst::GenericArg<'tcx>], + has_self: bool, + self_ty: Option<Ty<'tcx>>, + arg_count: &GenericArgCountResult, + ctx: &mut impl CreateSubstsForGenericArgsCtxt<'a, 'tcx>, +) -> SubstsRef<'tcx> { + // Collect the segments of the path; we need to substitute arguments + // for parameters throughout the entire path (wherever there are + // generic parameters). + let mut parent_defs = tcx.generics_of(def_id); + let count = parent_defs.count(); + let mut stack = vec![(def_id, parent_defs)]; + while let Some(def_id) = parent_defs.parent { + parent_defs = tcx.generics_of(def_id); + stack.push((def_id, parent_defs)); } - /// Creates the relevant generic argument substitutions - /// corresponding to a set of generic parameters. This is a - /// rather complex function. Let us try to explain the role - /// of each of its parameters: - /// - /// To start, we are given the `def_id` of the thing we are - /// creating the substitutions for, and a partial set of - /// substitutions `parent_substs`. In general, the substitutions - /// for an item begin with substitutions for all the "parents" of - /// that item -- e.g., for a method it might include the - /// parameters from the impl. - /// - /// Therefore, the method begins by walking down these parents, - /// starting with the outermost parent and proceed inwards until - /// it reaches `def_id`. For each parent `P`, it will check `parent_substs` - /// first to see if the parent's substitutions are listed in there. If so, - /// we can append those and move on. Otherwise, it invokes the - /// three callback functions: - /// - /// - `args_for_def_id`: given the `DefId` `P`, supplies back the - /// generic arguments that were given to that parent from within - /// the path; so e.g., if you have `<T as Foo>::Bar`, the `DefId` - /// might refer to the trait `Foo`, and the arguments might be - /// `[T]`. The boolean value indicates whether to infer values - /// for arguments whose values were not explicitly provided. - /// - `provided_kind`: given the generic parameter and the value from `args_for_def_id`, - /// instantiate a `GenericArg`. - /// - `inferred_kind`: if no parameter was provided, and inference is enabled, then - /// creates a suitable inference variable. - pub fn create_substs_for_generic_args<'a>( - tcx: TyCtxt<'tcx>, - def_id: DefId, - parent_substs: &[subst::GenericArg<'tcx>], - has_self: bool, - self_ty: Option<Ty<'tcx>>, - arg_count: &GenericArgCountResult, - ctx: &mut impl CreateSubstsForGenericArgsCtxt<'a, 'tcx>, - ) -> SubstsRef<'tcx> { - // Collect the segments of the path; we need to substitute arguments - // for parameters throughout the entire path (wherever there are - // generic parameters). - let mut parent_defs = tcx.generics_of(def_id); - let count = parent_defs.count(); - let mut stack = vec![(def_id, parent_defs)]; - while let Some(def_id) = parent_defs.parent { - parent_defs = tcx.generics_of(def_id); - stack.push((def_id, parent_defs)); + // We manually build up the substitution, rather than using convenience + // methods in `subst.rs`, so that we can iterate over the arguments and + // parameters in lock-step linearly, instead of trying to match each pair. + let mut substs: SmallVec<[subst::GenericArg<'tcx>; 8]> = SmallVec::with_capacity(count); + // Iterate over each segment of the path. + while let Some((def_id, defs)) = stack.pop() { + let mut params = defs.params.iter().peekable(); + + // If we have already computed substitutions for parents, we can use those directly. + while let Some(¶m) = params.peek() { + if let Some(&kind) = parent_substs.get(param.index as usize) { + substs.push(kind); + params.next(); + } else { + break; + } } - // We manually build up the substitution, rather than using convenience - // methods in `subst.rs`, so that we can iterate over the arguments and - // parameters in lock-step linearly, instead of trying to match each pair. - let mut substs: SmallVec<[subst::GenericArg<'tcx>; 8]> = SmallVec::with_capacity(count); - // Iterate over each segment of the path. - while let Some((def_id, defs)) = stack.pop() { - let mut params = defs.params.iter().peekable(); - - // If we have already computed substitutions for parents, we can use those directly. - while let Some(¶m) = params.peek() { - if let Some(&kind) = parent_substs.get(param.index as usize) { - substs.push(kind); - params.next(); - } else { - break; + // `Self` is handled first, unless it's been handled in `parent_substs`. + if has_self { + if let Some(¶m) = params.peek() { + if param.index == 0 { + if let GenericParamDefKind::Type { .. } = param.kind { + substs.push( + self_ty + .map(|ty| ty.into()) + .unwrap_or_else(|| ctx.inferred_kind(None, param, true)), + ); + params.next(); + } } } + } - // `Self` is handled first, unless it's been handled in `parent_substs`. - if has_self { - if let Some(¶m) = params.peek() { - if param.index == 0 { - if let GenericParamDefKind::Type { .. } = param.kind { - substs.push( - self_ty - .map(|ty| ty.into()) - .unwrap_or_else(|| ctx.inferred_kind(None, param, true)), - ); + // Check whether this segment takes generic arguments and the user has provided any. + let (generic_args, infer_args) = ctx.args_for_def_id(def_id); + + let args_iter = generic_args.iter().flat_map(|generic_args| generic_args.args.iter()); + let mut args = args_iter.clone().peekable(); + + // If we encounter a type or const when we expect a lifetime, we infer the lifetimes. + // If we later encounter a lifetime, we know that the arguments were provided in the + // wrong order. `force_infer_lt` records the type or const that forced lifetimes to be + // inferred, so we can use it for diagnostics later. + let mut force_infer_lt = None; + + loop { + // We're going to iterate through the generic arguments that the user + // provided, matching them with the generic parameters we expect. + // Mismatches can occur as a result of elided lifetimes, or for malformed + // input. We try to handle both sensibly. + match (args.peek(), params.peek()) { + (Some(&arg), Some(¶m)) => { + match (arg, ¶m.kind, arg_count.explicit_late_bound) { + (GenericArg::Lifetime(_), GenericParamDefKind::Lifetime, _) + | ( + GenericArg::Type(_) | GenericArg::Infer(_), + GenericParamDefKind::Type { .. }, + _, + ) + | ( + GenericArg::Const(_) | GenericArg::Infer(_), + GenericParamDefKind::Const { .. }, + _, + ) => { + substs.push(ctx.provided_kind(param, arg)); + args.next(); params.next(); } - } - } - } - - // Check whether this segment takes generic arguments and the user has provided any. - let (generic_args, infer_args) = ctx.args_for_def_id(def_id); - - let args_iter = generic_args.iter().flat_map(|generic_args| generic_args.args.iter()); - let mut args = args_iter.clone().peekable(); - - // If we encounter a type or const when we expect a lifetime, we infer the lifetimes. - // If we later encounter a lifetime, we know that the arguments were provided in the - // wrong order. `force_infer_lt` records the type or const that forced lifetimes to be - // inferred, so we can use it for diagnostics later. - let mut force_infer_lt = None; - - loop { - // We're going to iterate through the generic arguments that the user - // provided, matching them with the generic parameters we expect. - // Mismatches can occur as a result of elided lifetimes, or for malformed - // input. We try to handle both sensibly. - match (args.peek(), params.peek()) { - (Some(&arg), Some(¶m)) => { - match (arg, ¶m.kind, arg_count.explicit_late_bound) { - (GenericArg::Lifetime(_), GenericParamDefKind::Lifetime, _) - | ( - GenericArg::Type(_) | GenericArg::Infer(_), - GenericParamDefKind::Type { .. }, - _, - ) - | ( - GenericArg::Const(_) | GenericArg::Infer(_), - GenericParamDefKind::Const { .. }, - _, - ) => { - substs.push(ctx.provided_kind(param, arg)); - args.next(); - params.next(); - } - ( - GenericArg::Infer(_) | GenericArg::Type(_) | GenericArg::Const(_), - GenericParamDefKind::Lifetime, - _, - ) => { - // We expected a lifetime argument, but got a type or const - // argument. That means we're inferring the lifetimes. - substs.push(ctx.inferred_kind(None, param, infer_args)); - force_infer_lt = Some((arg, param)); - params.next(); - } - (GenericArg::Lifetime(_), _, ExplicitLateBound::Yes) => { - // We've come across a lifetime when we expected something else in - // the presence of explicit late bounds. This is most likely - // due to the presence of the explicit bound so we're just going to - // ignore it. - args.next(); - } - (_, _, _) => { - // We expected one kind of parameter, but the user provided - // another. This is an error. However, if we already know that - // the arguments don't match up with the parameters, we won't issue - // an additional error, as the user already knows what's wrong. - if arg_count.correct.is_ok() { - // We're going to iterate over the parameters to sort them out, and - // show that order to the user as a possible order for the parameters - let mut param_types_present = defs - .params - .iter() - .map(|param| (param.kind.to_ord(), param.clone())) - .collect::<Vec<(ParamKindOrd, GenericParamDef)>>(); - param_types_present.sort_by_key(|(ord, _)| *ord); - let (mut param_types_present, ordered_params): ( - Vec<ParamKindOrd>, - Vec<GenericParamDef>, - ) = param_types_present.into_iter().unzip(); - param_types_present.dedup(); - - Self::generic_arg_mismatch_err( - tcx, - arg, - param, - !args_iter.clone().is_sorted_by_key(|arg| arg.to_ord()), - Some(&format!( - "reorder the arguments: {}: `<{}>`", - param_types_present - .into_iter() - .map(|ord| format!("{}s", ord)) - .collect::<Vec<String>>() - .join(", then "), - ordered_params - .into_iter() - .filter_map(|param| { - if param.name == kw::SelfUpper { - None - } else { - Some(param.name.to_string()) - } - }) - .collect::<Vec<String>>() - .join(", ") - )), - ); - } - - // We've reported the error, but we want to make sure that this - // problem doesn't bubble down and create additional, irrelevant - // errors. In this case, we're simply going to ignore the argument - // and any following arguments. The rest of the parameters will be - // inferred. - while args.next().is_some() {} - } + ( + GenericArg::Infer(_) | GenericArg::Type(_) | GenericArg::Const(_), + GenericParamDefKind::Lifetime, + _, + ) => { + // We expected a lifetime argument, but got a type or const + // argument. That means we're inferring the lifetimes. + substs.push(ctx.inferred_kind(None, param, infer_args)); + force_infer_lt = Some((arg, param)); + params.next(); } - } - - (Some(&arg), None) => { - // We should never be able to reach this point with well-formed input. - // There are three situations in which we can encounter this issue. - // - // 1. The number of arguments is incorrect. In this case, an error - // will already have been emitted, and we can ignore it. - // 2. There are late-bound lifetime parameters present, yet the - // lifetime arguments have also been explicitly specified by the - // user. - // 3. We've inferred some lifetimes, which have been provided later (i.e. - // after a type or const). We want to throw an error in this case. - - if arg_count.correct.is_ok() - && arg_count.explicit_late_bound == ExplicitLateBound::No - { - let kind = arg.descr(); - assert_eq!(kind, "lifetime"); - let (provided_arg, param) = - force_infer_lt.expect("lifetimes ought to have been inferred"); - Self::generic_arg_mismatch_err(tcx, provided_arg, param, false, None); + (GenericArg::Lifetime(_), _, ExplicitLateBound::Yes) => { + // We've come across a lifetime when we expected something else in + // the presence of explicit late bounds. This is most likely + // due to the presence of the explicit bound so we're just going to + // ignore it. + args.next(); } + (_, _, _) => { + // We expected one kind of parameter, but the user provided + // another. This is an error. However, if we already know that + // the arguments don't match up with the parameters, we won't issue + // an additional error, as the user already knows what's wrong. + if arg_count.correct.is_ok() { + // We're going to iterate over the parameters to sort them out, and + // show that order to the user as a possible order for the parameters + let mut param_types_present = defs + .params + .iter() + .map(|param| (param.kind.to_ord(), param.clone())) + .collect::<Vec<(ParamKindOrd, GenericParamDef)>>(); + param_types_present.sort_by_key(|(ord, _)| *ord); + let (mut param_types_present, ordered_params): ( + Vec<ParamKindOrd>, + Vec<GenericParamDef>, + ) = param_types_present.into_iter().unzip(); + param_types_present.dedup(); + + generic_arg_mismatch_err( + tcx, + arg, + param, + !args_iter.clone().is_sorted_by_key(|arg| arg.to_ord()), + Some(&format!( + "reorder the arguments: {}: `<{}>`", + param_types_present + .into_iter() + .map(|ord| format!("{}s", ord)) + .collect::<Vec<String>>() + .join(", then "), + ordered_params + .into_iter() + .filter_map(|param| { + if param.name == kw::SelfUpper { + None + } else { + Some(param.name.to_string()) + } + }) + .collect::<Vec<String>>() + .join(", ") + )), + ); + } - break; + // We've reported the error, but we want to make sure that this + // problem doesn't bubble down and create additional, irrelevant + // errors. In this case, we're simply going to ignore the argument + // and any following arguments. The rest of the parameters will be + // inferred. + while args.next().is_some() {} + } } + } - (None, Some(¶m)) => { - // If there are fewer arguments than parameters, it means - // we're inferring the remaining arguments. - substs.push(ctx.inferred_kind(Some(&substs), param, infer_args)); - params.next(); + (Some(&arg), None) => { + // We should never be able to reach this point with well-formed input. + // There are three situations in which we can encounter this issue. + // + // 1. The number of arguments is incorrect. In this case, an error + // will already have been emitted, and we can ignore it. + // 2. There are late-bound lifetime parameters present, yet the + // lifetime arguments have also been explicitly specified by the + // user. + // 3. We've inferred some lifetimes, which have been provided later (i.e. + // after a type or const). We want to throw an error in this case. + + if arg_count.correct.is_ok() + && arg_count.explicit_late_bound == ExplicitLateBound::No + { + let kind = arg.descr(); + assert_eq!(kind, "lifetime"); + let (provided_arg, param) = + force_infer_lt.expect("lifetimes ought to have been inferred"); + generic_arg_mismatch_err(tcx, provided_arg, param, false, None); } - (None, None) => break, + break; + } + + (None, Some(¶m)) => { + // If there are fewer arguments than parameters, it means + // we're inferring the remaining arguments. + substs.push(ctx.inferred_kind(Some(&substs), param, infer_args)); + params.next(); } + + (None, None) => break, } } - - tcx.intern_substs(&substs) } - /// Checks that the correct number of generic arguments have been provided. - /// Used specifically for function calls. - pub fn check_generic_arg_count_for_call( - tcx: TyCtxt<'_>, - span: Span, - def_id: DefId, - generics: &ty::Generics, - seg: &hir::PathSegment<'_>, - is_method_call: IsMethodCall, - ) -> GenericArgCountResult { - let empty_args = hir::GenericArgs::none(); - let gen_args = seg.args.unwrap_or(&empty_args); - let gen_pos = if is_method_call == IsMethodCall::Yes { - GenericArgPosition::MethodCall + tcx.intern_substs(&substs) +} + +/// Checks that the correct number of generic arguments have been provided. +/// Used specifically for function calls. +pub fn check_generic_arg_count_for_call( + tcx: TyCtxt<'_>, + span: Span, + def_id: DefId, + generics: &ty::Generics, + seg: &hir::PathSegment<'_>, + is_method_call: IsMethodCall, +) -> GenericArgCountResult { + let empty_args = hir::GenericArgs::none(); + let gen_args = seg.args.unwrap_or(&empty_args); + let gen_pos = if is_method_call == IsMethodCall::Yes { + GenericArgPosition::MethodCall + } else { + GenericArgPosition::Value + }; + let has_self = generics.parent.is_none() && generics.has_self; + + check_generic_arg_count( + tcx, + span, + def_id, + seg, + generics, + gen_args, + gen_pos, + has_self, + seg.infer_args, + ) +} + +/// Checks that the correct number of generic arguments have been provided. +/// This is used both for datatypes and function calls. +#[instrument(skip(tcx, gen_pos), level = "debug")] +pub(crate) fn check_generic_arg_count( + tcx: TyCtxt<'_>, + span: Span, + def_id: DefId, + seg: &hir::PathSegment<'_>, + gen_params: &ty::Generics, + gen_args: &hir::GenericArgs<'_>, + gen_pos: GenericArgPosition, + has_self: bool, + infer_args: bool, +) -> GenericArgCountResult { + let default_counts = gen_params.own_defaults(); + let param_counts = gen_params.own_counts(); + + // Subtracting from param count to ensure type params synthesized from `impl Trait` + // cannot be explicitly specified. + let synth_type_param_count = gen_params + .params + .iter() + .filter(|param| matches!(param.kind, ty::GenericParamDefKind::Type { synthetic: true, .. })) + .count(); + let named_type_param_count = param_counts.types - has_self as usize - synth_type_param_count; + let infer_lifetimes = + (gen_pos != GenericArgPosition::Type || infer_args) && !gen_args.has_lifetime_params(); + + if gen_pos != GenericArgPosition::Type && let Some(b) = gen_args.bindings.first() { + prohibit_assoc_ty_binding(tcx, b.span); + } + + let explicit_late_bound = + prohibit_explicit_late_bound_lifetimes(tcx, gen_params, gen_args, gen_pos); + + let mut invalid_args = vec![]; + + let mut check_lifetime_args = |min_expected_args: usize, + max_expected_args: usize, + provided_args: usize, + late_bounds_ignore: bool| { + if (min_expected_args..=max_expected_args).contains(&provided_args) { + return Ok(()); + } + + if late_bounds_ignore { + return Ok(()); + } + + if provided_args > max_expected_args { + invalid_args.extend( + gen_args.args[max_expected_args..provided_args].iter().map(|arg| arg.span()), + ); + }; + + let gen_args_info = if provided_args > min_expected_args { + invalid_args.extend( + gen_args.args[min_expected_args..provided_args].iter().map(|arg| arg.span()), + ); + let num_redundant_args = provided_args - min_expected_args; + GenericArgsInfo::ExcessLifetimes { num_redundant_args } } else { - GenericArgPosition::Value + let num_missing_args = min_expected_args - provided_args; + GenericArgsInfo::MissingLifetimes { num_missing_args } }; - let has_self = generics.parent.is_none() && generics.has_self; - Self::check_generic_arg_count( + let reported = WrongNumberOfGenericArgs::new( tcx, - span, - def_id, + gen_args_info, seg, - generics, + gen_params, + has_self as usize, gen_args, - gen_pos, - has_self, - seg.infer_args, + def_id, ) - } - - /// Checks that the correct number of generic arguments have been provided. - /// This is used both for datatypes and function calls. - #[instrument(skip(tcx, gen_pos), level = "debug")] - pub(crate) fn check_generic_arg_count( - tcx: TyCtxt<'_>, - span: Span, - def_id: DefId, - seg: &hir::PathSegment<'_>, - gen_params: &ty::Generics, - gen_args: &hir::GenericArgs<'_>, - gen_pos: GenericArgPosition, - has_self: bool, - infer_args: bool, - ) -> GenericArgCountResult { - let default_counts = gen_params.own_defaults(); - let param_counts = gen_params.own_counts(); - - // Subtracting from param count to ensure type params synthesized from `impl Trait` - // cannot be explicitly specified. - let synth_type_param_count = gen_params - .params - .iter() - .filter(|param| { - matches!(param.kind, ty::GenericParamDefKind::Type { synthetic: true, .. }) - }) - .count(); - let named_type_param_count = - param_counts.types - has_self as usize - synth_type_param_count; - let infer_lifetimes = - (gen_pos != GenericArgPosition::Type || infer_args) && !gen_args.has_lifetime_params(); - - if gen_pos != GenericArgPosition::Type && let Some(b) = gen_args.bindings.first() { - Self::prohibit_assoc_ty_binding(tcx, b.span); + .diagnostic() + .emit(); + + Err(reported) + }; + + let min_expected_lifetime_args = if infer_lifetimes { 0 } else { param_counts.lifetimes }; + let max_expected_lifetime_args = param_counts.lifetimes; + let num_provided_lifetime_args = gen_args.num_lifetime_params(); + + let lifetimes_correct = check_lifetime_args( + min_expected_lifetime_args, + max_expected_lifetime_args, + num_provided_lifetime_args, + explicit_late_bound == ExplicitLateBound::Yes, + ); + + let mut check_types_and_consts = |expected_min, + expected_max, + expected_max_with_synth, + provided, + params_offset, + args_offset| { + debug!( + ?expected_min, + ?expected_max, + ?provided, + ?params_offset, + ?args_offset, + "check_types_and_consts" + ); + if (expected_min..=expected_max).contains(&provided) { + return Ok(()); } - let explicit_late_bound = - Self::prohibit_explicit_late_bound_lifetimes(tcx, gen_params, gen_args, gen_pos); - - let mut invalid_args = vec![]; + let num_default_params = expected_max - expected_min; - let mut check_lifetime_args = - |min_expected_args: usize, - max_expected_args: usize, - provided_args: usize, - late_bounds_ignore: bool| { - if (min_expected_args..=max_expected_args).contains(&provided_args) { - return Ok(()); - } - - if late_bounds_ignore { - return Ok(()); - } + let gen_args_info = if provided > expected_max { + invalid_args.extend( + gen_args.args[args_offset + expected_max..args_offset + provided] + .iter() + .map(|arg| arg.span()), + ); + let num_redundant_args = provided - expected_max; - if provided_args > max_expected_args { - invalid_args.extend( - gen_args.args[max_expected_args..provided_args] - .iter() - .map(|arg| arg.span()), - ); - }; - - let gen_args_info = if provided_args > min_expected_args { - invalid_args.extend( - gen_args.args[min_expected_args..provided_args] - .iter() - .map(|arg| arg.span()), - ); - let num_redundant_args = provided_args - min_expected_args; - GenericArgsInfo::ExcessLifetimes { num_redundant_args } - } else { - let num_missing_args = min_expected_args - provided_args; - GenericArgsInfo::MissingLifetimes { num_missing_args } - }; - - let reported = WrongNumberOfGenericArgs::new( - tcx, - gen_args_info, - seg, - gen_params, - has_self as usize, - gen_args, - def_id, - ) - .diagnostic() - .emit(); - - Err(reported) - }; - - let min_expected_lifetime_args = if infer_lifetimes { 0 } else { param_counts.lifetimes }; - let max_expected_lifetime_args = param_counts.lifetimes; - let num_provided_lifetime_args = gen_args.num_lifetime_params(); - - let lifetimes_correct = check_lifetime_args( - min_expected_lifetime_args, - max_expected_lifetime_args, - num_provided_lifetime_args, - explicit_late_bound == ExplicitLateBound::Yes, - ); + // Provide extra note if synthetic arguments like `impl Trait` are specified. + let synth_provided = provided <= expected_max_with_synth; - let mut check_types_and_consts = |expected_min, - expected_max, - expected_max_with_synth, - provided, - params_offset, - args_offset| { - debug!( - ?expected_min, - ?expected_max, - ?provided, - ?params_offset, - ?args_offset, - "check_types_and_consts" - ); - if (expected_min..=expected_max).contains(&provided) { - return Ok(()); + GenericArgsInfo::ExcessTypesOrConsts { + num_redundant_args, + num_default_params, + args_offset, + synth_provided, } + } else { + let num_missing_args = expected_max - provided; - let num_default_params = expected_max - expected_min; - - let gen_args_info = if provided > expected_max { - invalid_args.extend( - gen_args.args[args_offset + expected_max..args_offset + provided] - .iter() - .map(|arg| arg.span()), - ); - let num_redundant_args = provided - expected_max; + GenericArgsInfo::MissingTypesOrConsts { + num_missing_args, + num_default_params, + args_offset, + } + }; - // Provide extra note if synthetic arguments like `impl Trait` are specified. - let synth_provided = provided <= expected_max_with_synth; + debug!(?gen_args_info); - GenericArgsInfo::ExcessTypesOrConsts { - num_redundant_args, - num_default_params, - args_offset, - synth_provided, - } - } else { - let num_missing_args = expected_max - provided; + let reported = WrongNumberOfGenericArgs::new( + tcx, + gen_args_info, + seg, + gen_params, + params_offset, + gen_args, + def_id, + ) + .diagnostic() + .emit_unless(gen_args.has_err()); - GenericArgsInfo::MissingTypesOrConsts { - num_missing_args, - num_default_params, - args_offset, - } - }; - - debug!(?gen_args_info); - - let reported = WrongNumberOfGenericArgs::new( - tcx, - gen_args_info, - seg, - gen_params, - params_offset, - gen_args, - def_id, - ) - .diagnostic() - .emit_unless(gen_args.has_err()); - - Err(reported) - }; + Err(reported) + }; - let args_correct = { - let expected_min = if infer_args { - 0 - } else { - param_counts.consts + named_type_param_count - - default_counts.types - - default_counts.consts - }; - debug!(?expected_min); - debug!(arg_counts.lifetimes=?gen_args.num_lifetime_params()); - - check_types_and_consts( - expected_min, - param_counts.consts + named_type_param_count, - param_counts.consts + named_type_param_count + synth_type_param_count, - gen_args.num_generic_params(), - param_counts.lifetimes + has_self as usize, - gen_args.num_lifetime_params(), - ) + let args_correct = { + let expected_min = if infer_args { + 0 + } else { + param_counts.consts + named_type_param_count + - default_counts.types + - default_counts.consts }; + debug!(?expected_min); + debug!(arg_counts.lifetimes=?gen_args.num_lifetime_params()); + + check_types_and_consts( + expected_min, + param_counts.consts + named_type_param_count, + param_counts.consts + named_type_param_count + synth_type_param_count, + gen_args.num_generic_params(), + param_counts.lifetimes + has_self as usize, + gen_args.num_lifetime_params(), + ) + }; - GenericArgCountResult { - explicit_late_bound, - correct: lifetimes_correct.and(args_correct).map_err(|reported| { - GenericArgCountMismatch { reported: Some(reported), invalid_args } - }), - } + GenericArgCountResult { + explicit_late_bound, + correct: lifetimes_correct + .and(args_correct) + .map_err(|reported| GenericArgCountMismatch { reported: Some(reported), invalid_args }), } +} - /// Emits an error regarding forbidden type binding associations - pub fn prohibit_assoc_ty_binding(tcx: TyCtxt<'_>, span: Span) { - tcx.sess.emit_err(AssocTypeBindingNotAllowed { span }); - } +/// Emits an error regarding forbidden type binding associations +pub fn prohibit_assoc_ty_binding(tcx: TyCtxt<'_>, span: Span) { + tcx.sess.emit_err(AssocTypeBindingNotAllowed { span }); +} - /// Prohibits explicit lifetime arguments if late-bound lifetime parameters - /// are present. This is used both for datatypes and function calls. - pub(crate) fn prohibit_explicit_late_bound_lifetimes( - tcx: TyCtxt<'_>, - def: &ty::Generics, - args: &hir::GenericArgs<'_>, - position: GenericArgPosition, - ) -> ExplicitLateBound { - let param_counts = def.own_counts(); - let infer_lifetimes = position != GenericArgPosition::Type && !args.has_lifetime_params(); - - if infer_lifetimes { - return ExplicitLateBound::No; - } +/// Prohibits explicit lifetime arguments if late-bound lifetime parameters +/// are present. This is used both for datatypes and function calls. +pub(crate) fn prohibit_explicit_late_bound_lifetimes( + tcx: TyCtxt<'_>, + def: &ty::Generics, + args: &hir::GenericArgs<'_>, + position: GenericArgPosition, +) -> ExplicitLateBound { + let param_counts = def.own_counts(); + let infer_lifetimes = position != GenericArgPosition::Type && !args.has_lifetime_params(); + + if infer_lifetimes { + return ExplicitLateBound::No; + } - if let Some(span_late) = def.has_late_bound_regions { - let msg = "cannot specify lifetime arguments explicitly \ + if let Some(span_late) = def.has_late_bound_regions { + let msg = "cannot specify lifetime arguments explicitly \ if late bound lifetime parameters are present"; - let note = "the late bound lifetime parameter is introduced here"; - let span = args.args[0].span(); - - if position == GenericArgPosition::Value - && args.num_lifetime_params() != param_counts.lifetimes - { - let mut err = tcx.sess.struct_span_err(span, msg); - err.span_note(span_late, note); - err.emit(); - } else { - let mut multispan = MultiSpan::from_span(span); - multispan.push_span_label(span_late, note); - tcx.struct_span_lint_hir( - LATE_BOUND_LIFETIME_ARGUMENTS, - args.args[0].hir_id(), - multispan, - msg, - |lint| lint, - ); - } - - ExplicitLateBound::Yes + let note = "the late bound lifetime parameter is introduced here"; + let span = args.args[0].span(); + + if position == GenericArgPosition::Value + && args.num_lifetime_params() != param_counts.lifetimes + { + let mut err = tcx.sess.struct_span_err(span, msg); + err.span_note(span_late, note); + err.emit(); } else { - ExplicitLateBound::No + let mut multispan = MultiSpan::from_span(span); + multispan.push_span_label(span_late, note); + tcx.struct_span_lint_hir( + LATE_BOUND_LIFETIME_ARGUMENTS, + args.args[0].hir_id(), + multispan, + msg, + |lint| lint, + ); } + + ExplicitLateBound::Yes + } else { + ExplicitLateBound::No } } diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs index 78d204d47..6435b05ce 100644 --- a/compiler/rustc_hir_analysis/src/astconv/mod.rs +++ b/compiler/rustc_hir_analysis/src/astconv/mod.rs @@ -3,8 +3,11 @@ //! instance of `AstConv`. mod errors; -mod generics; +pub mod generics; +use crate::astconv::generics::{ + check_generic_arg_count, create_substs_for_generic_args, prohibit_assoc_ty_binding, +}; use crate::bounds::Bounds; use crate::collect::HirPlaceholderCollector; use crate::errors::{ @@ -24,13 +27,12 @@ use rustc_hir::def::{CtorOf, DefKind, Namespace, Res}; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::intravisit::{walk_generics, Visitor as _}; use rustc_hir::{GenericArg, GenericArgs, OpaqueTyOrigin}; +use rustc_infer::infer::TyCtxtInferExt; use rustc_middle::middle::stability::AllowUnstable; use rustc_middle::ty::subst::{self, GenericArgKind, InternalSubsts, SubstsRef}; -use rustc_middle::ty::DynKind; use rustc_middle::ty::GenericParamDefKind; -use rustc_middle::ty::{ - self, Const, DefIdTree, EarlyBinder, IsSuggestable, Ty, TyCtxt, TypeVisitable, -}; +use rustc_middle::ty::{self, Const, DefIdTree, IsSuggestable, Ty, TyCtxt, TypeVisitable}; +use rustc_middle::ty::{DynKind, EarlyBinder}; use rustc_session::lint::builtin::{AMBIGUOUS_ASSOCIATED_ITEMS, BARE_TRAIT_OBJECTS}; use rustc_span::edition::Edition; use rustc_span::lev_distance::find_best_match_for_name; @@ -108,11 +110,12 @@ pub trait AstConv<'tcx> { poly_trait_ref: ty::PolyTraitRef<'tcx>, ) -> Ty<'tcx>; - /// Normalize an associated type coming from the user. - /// - /// This should only be used by astconv. Use `FnCtxt::normalize` - /// or `ObligationCtxt::normalize` in downstream crates. - fn normalize_ty(&self, span: Span, ty: Ty<'tcx>) -> Ty<'tcx>; + /// Returns `AdtDef` if `ty` is an ADT. + /// Note that `ty` might be a projection type that needs normalization. + /// This used to get the enum variants in scope of the type. + /// For example, `Self::A` could refer to an associated type + /// or to an enum variant depending on the result of this function. + fn probe_adt(&self, span: Span, ty: Ty<'tcx>) -> Option<ty::AdtDef<'tcx>>; /// Invoked when we encounter an error from some prior pass /// (e.g., resolve) that is translated into a ty-error. This is @@ -121,6 +124,13 @@ pub trait AstConv<'tcx> { fn set_tainted_by_errors(&self, e: ErrorGuaranteed); fn record_ty(&self, hir_id: hir::HirId, ty: Ty<'tcx>, span: Span); + + fn astconv(&self) -> &dyn AstConv<'tcx> + where + Self: Sized, + { + self + } } #[derive(Debug)] @@ -280,7 +290,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ty::BoundConstness::NotConst, ); if let Some(b) = item_segment.args().bindings.first() { - Self::prohibit_assoc_ty_binding(self.tcx(), b.span); + prohibit_assoc_ty_binding(self.tcx(), b.span); } substs @@ -350,7 +360,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { assert!(self_ty.is_none()); } - let arg_count = Self::check_generic_arg_count( + let arg_count = check_generic_arg_count( tcx, span, def_id, @@ -487,13 +497,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // Avoid ICE #86756 when type error recovery goes awry. return tcx.ty_error().into(); } - self.astconv - .normalize_ty( - self.span, - EarlyBinder(tcx.at(self.span).type_of(param.def_id)) - .subst(tcx, substs), - ) - .into() + tcx.at(self.span).bound_type_of(param.def_id).subst(tcx, substs).into() } else if infer_args { self.astconv.ty_infer(Some(param), self.span).into() } else { @@ -507,9 +511,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { return tcx.const_error(ty).into(); } if !infer_args && has_default { - tcx.bound_const_param_default(param.def_id) - .subst(tcx, substs.unwrap()) - .into() + tcx.const_param_default(param.def_id).subst(tcx, substs.unwrap()).into() } else { if infer_args { self.astconv.ct_infer(ty, Some(param), self.span).into() @@ -531,7 +533,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { inferred_params: vec![], infer_args, }; - let substs = Self::create_substs_for_generic_args( + let substs = create_substs_for_generic_args( tcx, def_id, parent_substs, @@ -567,17 +569,17 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { .bindings .iter() .map(|binding| { - let kind = match binding.kind { - hir::TypeBindingKind::Equality { ref term } => match term { - hir::Term::Ty(ref ty) => { + let kind = match &binding.kind { + hir::TypeBindingKind::Equality { term } => match term { + hir::Term::Ty(ty) => { ConvertedBindingKind::Equality(self.ast_ty_to_ty(ty).into()) } - hir::Term::Const(ref c) => { + hir::Term::Const(c) => { let c = Const::from_anon_const(self.tcx(), c.def_id); ConvertedBindingKind::Equality(c.into()) } }, - hir::TypeBindingKind::Constraint { ref bounds } => { + hir::TypeBindingKind::Constraint { bounds } => { ConvertedBindingKind::Constraint(bounds) } }; @@ -617,7 +619,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ); if let Some(b) = item_segment.args().bindings.first() { - Self::prohibit_assoc_ty_binding(self.tcx(), b.span); + prohibit_assoc_ty_binding(self.tcx(), b.span); } args @@ -680,10 +682,10 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let assoc_bindings = self.create_assoc_bindings_for_generic_args(args); let poly_trait_ref = - ty::Binder::bind_with_vars(ty::TraitRef::new(trait_def_id, substs), bound_vars); + ty::Binder::bind_with_vars(tcx.mk_trait_ref(trait_def_id, substs), bound_vars); debug!(?poly_trait_ref, ?assoc_bindings); - bounds.trait_bounds.push((poly_trait_ref, span, constness)); + bounds.push_trait_bound(tcx, poly_trait_ref, span, constness); let mut dup_bindings = FxHashMap::default(); for binding in &assoc_bindings { @@ -811,9 +813,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { constness, ); if let Some(b) = trait_segment.args().bindings.first() { - Self::prohibit_assoc_ty_binding(self.tcx(), b.span); + prohibit_assoc_ty_binding(self.tcx(), b.span); } - ty::TraitRef::new(trait_def_id, substs) + self.tcx().mk_trait_ref(trait_def_id, substs) } #[instrument(level = "debug", skip(self, span))] @@ -854,18 +856,19 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } /// Sets `implicitly_sized` to true on `Bounds` if necessary - pub(crate) fn add_implicitly_sized<'hir>( + pub(crate) fn add_implicitly_sized( &self, - bounds: &mut Bounds<'hir>, - ast_bounds: &'hir [hir::GenericBound<'hir>], - self_ty_where_predicates: Option<(LocalDefId, &'hir [hir::WherePredicate<'hir>])>, + bounds: &mut Bounds<'tcx>, + self_ty: Ty<'tcx>, + ast_bounds: &'tcx [hir::GenericBound<'tcx>], + self_ty_where_predicates: Option<(LocalDefId, &'tcx [hir::WherePredicate<'tcx>])>, span: Span, ) { let tcx = self.tcx(); // Try to find an unbound in bounds. let mut unbound = None; - let mut search_bounds = |ast_bounds: &'hir [hir::GenericBound<'hir>]| { + let mut search_bounds = |ast_bounds: &'tcx [hir::GenericBound<'tcx>]| { for ab in ast_bounds { if let hir::GenericBound::Trait(ptr, hir::TraitBoundModifier::Maybe) = ab { if unbound.is_none() { @@ -913,7 +916,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // No lang item for `Sized`, so we can't add it as a bound. return; } - bounds.implicitly_sized = Some(span); + bounds.push_sized(tcx, self_ty, span); } /// This helper takes a *converted* parameter type (`param_ty`) @@ -964,10 +967,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } hir::GenericBound::Outlives(lifetime) => { let region = self.ast_region_to_region(lifetime, None); - bounds.region_bounds.push(( - ty::Binder::bind_with_vars(region, bound_vars), + bounds.push_region_bound( + self.tcx(), + ty::Binder::bind_with_vars( + ty::OutlivesPredicate(param_ty, region), + bound_vars, + ), lifetime.ident.span, - )); + ); } } } @@ -985,7 +992,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { /// ``` /// /// The `sized_by_default` parameter indicates if, in this context, the `param_ty` should be - /// considered `Sized` unless there is an explicit `?Sized` bound. This would be true in the + /// considered `Sized` unless there is an explicit `?Sized` bound. This would be true in the /// example above, but is not true in supertrait listings like `trait Foo: Bar + Baz`. /// /// `span` should be the declaration size of the parameter. @@ -1146,10 +1153,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { debug!(?substs_trait_ref_and_assoc_item); - ty::ProjectionTy { - item_def_id: assoc_item.def_id, - substs: substs_trait_ref_and_assoc_item, - } + self.tcx().mk_alias_ty(assoc_item.def_id, substs_trait_ref_and_assoc_item) }); if !speculative { @@ -1195,7 +1199,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // the "projection predicate" for: // // `<T as Iterator>::Item = u32` - let assoc_item_def_id = projection_ty.skip_binder().item_def_id; + let assoc_item_def_id = projection_ty.skip_binder().def_id; let def_kind = tcx.def_kind(assoc_item_def_id); match (def_kind, term.unpack()) { (hir::def::DefKind::AssocTy, ty::TermKind::Ty(_)) @@ -1203,17 +1207,26 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { (_, _) => { let got = if let Some(_) = term.ty() { "type" } else { "constant" }; let expected = def_kind.descr(assoc_item_def_id); - let reported = tcx - .sess - .struct_span_err( + let mut err = tcx.sess.struct_span_err( + binding.span, + &format!("expected {expected} bound, found {got}"), + ); + err.span_note( + tcx.def_span(assoc_item_def_id), + &format!("{expected} defined here"), + ); + + if let hir::def::DefKind::AssocConst = def_kind + && let Some(t) = term.ty() && (t.is_enum() || t.references_error()) + && tcx.features().associated_const_equality { + err.span_suggestion( binding.span, - &format!("expected {expected} bound, found {got}"), - ) - .span_note( - tcx.def_span(assoc_item_def_id), - &format!("{expected} defined here"), - ) - .emit(); + "if equating a const, try wrapping with braces", + format!("{} = {{ const }}", binding.item_name), + Applicability::HasPlaceholders, + ); + } + let reported = err.emit(); term = match def_kind { hir::def::DefKind::AssocTy => { tcx.ty_error_with_guaranteed(reported).into() @@ -1229,13 +1242,12 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { }; } } - bounds.projection_bounds.push(( - projection_ty.map_bound(|projection_ty| ty::ProjectionPredicate { - projection_ty, - term: term, - }), + bounds.push_projection_bound( + tcx, + projection_ty + .map_bound(|projection_ty| ty::ProjectionPredicate { projection_ty, term }), binding.span, - )); + ); } ConvertedBindingKind::Constraint(ast_bounds) => { // "Desugar" a constraint like `T: Iterator<Item: Debug>` to @@ -1244,7 +1256,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // // Calling `skip_binder` is okay, because `add_bounds` expects the `param_ty` // parameter to have a skipped binder. - let param_ty = tcx.mk_ty(ty::Projection(projection_ty.skip_binder())); + let param_ty = tcx.mk_ty(ty::Alias(ty::Projection, projection_ty.skip_binder())); self.add_bounds(param_ty, ast_bounds.iter(), bounds, candidate.bound_vars()); } } @@ -1258,16 +1270,13 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { item_segment: &hir::PathSegment<'_>, ) -> Ty<'tcx> { let substs = self.ast_path_substs_for_ty(span, did, item_segment); - self.normalize_ty( - span, - EarlyBinder(self.tcx().at(span).type_of(did)).subst(self.tcx(), substs), - ) + self.tcx().at(span).bound_type_of(did).subst(self.tcx(), substs) } fn conv_object_ty_poly_trait_ref( &self, span: Span, - trait_bounds: &[hir::PolyTraitRef<'_>], + hir_trait_bounds: &[hir::PolyTraitRef<'_>], lifetime: &hir::Lifetime, borrowed: bool, representation: DynKind, @@ -1277,7 +1286,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let mut bounds = Bounds::default(); let mut potential_assoc_types = Vec::new(); let dummy_self = self.tcx().types.trait_object_dummy_self; - for trait_bound in trait_bounds.iter().rev() { + for trait_bound in hir_trait_bounds.iter().rev() { if let GenericArgCountResult { correct: Err(GenericArgCountMismatch { invalid_args: cur_potential_assoc_types, .. }), @@ -1294,10 +1303,45 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } } + let mut trait_bounds = vec![]; + let mut projection_bounds = vec![]; + for (pred, span) in bounds.predicates() { + let bound_pred = pred.kind(); + match bound_pred.skip_binder() { + ty::PredicateKind::Clause(clause) => match clause { + ty::Clause::Trait(trait_pred) => { + assert_eq!(trait_pred.polarity, ty::ImplPolarity::Positive); + trait_bounds.push(( + bound_pred.rebind(trait_pred.trait_ref), + span, + trait_pred.constness, + )); + } + ty::Clause::Projection(proj) => { + projection_bounds.push((bound_pred.rebind(proj), span)); + } + ty::Clause::TypeOutlives(_) => { + // Do nothing, we deal with regions separately + } + ty::Clause::RegionOutlives(_) => bug!(), + }, + ty::PredicateKind::WellFormed(_) + | ty::PredicateKind::ObjectSafe(_) + | ty::PredicateKind::ClosureKind(_, _, _) + | ty::PredicateKind::Subtype(_) + | ty::PredicateKind::Coerce(_) + | ty::PredicateKind::ConstEvaluatable(_) + | ty::PredicateKind::ConstEquate(_, _) + | ty::PredicateKind::TypeWellFormedFromEnv(_) + | ty::PredicateKind::Ambiguous => bug!(), + } + } + // Expand trait aliases recursively and check that only one regular (non-auto) trait // is used and no 'maybe' bounds are used. let expanded_traits = - traits::expand_trait_aliases(tcx, bounds.trait_bounds.iter().map(|&(a, b, _)| (a, b))); + traits::expand_trait_aliases(tcx, trait_bounds.iter().map(|&(a, b, _)| (a, b))); + let (mut auto_traits, regular_traits): (Vec<_>, Vec<_>) = expanded_traits .filter(|i| i.trait_ref().self_ty().skip_binder() == dummy_self) .partition(|i| tcx.trait_is_auto(i.trait_ref().def_id())); @@ -1334,8 +1378,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } if regular_traits.is_empty() && auto_traits.is_empty() { - let trait_alias_span = bounds - .trait_bounds + let trait_alias_span = trait_bounds .iter() .map(|&(trait_ref, _, _)| trait_ref.def_id()) .find(|&trait_ref| tcx.is_trait_alias(trait_ref)) @@ -1366,8 +1409,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // Use a `BTreeSet` to keep output in a more consistent order. let mut associated_types: FxHashMap<Span, BTreeSet<DefId>> = FxHashMap::default(); - let regular_traits_refs_spans = bounds - .trait_bounds + let regular_traits_refs_spans = trait_bounds .into_iter() .filter(|(trait_ref, _, _)| !tcx.trait_is_auto(trait_ref.def_id())); @@ -1421,7 +1463,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // the discussion in #56288 for alternatives. if !references_self { // Include projections defined on supertraits. - bounds.projection_bounds.push((pred, span)); + projection_bounds.push((pred, span)); } } _ => (), @@ -1429,7 +1471,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } } - for (projection_bound, _) in &bounds.projection_bounds { + for (projection_bound, _) in &projection_bounds { for def_ids in associated_types.values_mut() { def_ids.remove(&projection_bound.projection_def_id()); } @@ -1438,7 +1480,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { self.complain_about_missing_associated_types( associated_types, potential_assoc_types, - trait_bounds, + hir_trait_bounds, ); // De-duplicate auto traits so that, e.g., `dyn Trait + Send + Send` is the same as @@ -1455,7 +1497,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { i.trait_ref().map_bound(|trait_ref: ty::TraitRef<'tcx>| { assert_eq!(trait_ref.self_ty(), dummy_self); - // Verify that `dummy_self` did not leak inside default type parameters. This + // Verify that `dummy_self` did not leak inside default type parameters. This // could not be done at path creation, since we need to see through trait aliases. let mut missing_type_params = vec![]; let mut references_self = false; @@ -1480,7 +1522,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let substs = tcx.intern_substs(&substs[..]); let span = i.bottom().1; - let empty_generic_args = trait_bounds.iter().any(|hir_bound| { + let empty_generic_args = hir_trait_bounds.iter().any(|hir_bound| { hir_bound.trait_ref.path.res == Res::Def(DefKind::Trait, trait_ref.def_id) && hir_bound.span.contains(span) }); @@ -1512,7 +1554,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { }) }); - let existential_projections = bounds.projection_bounds.iter().map(|(bound, _)| { + let existential_projections = projection_bounds.iter().map(|(bound, _)| { bound.map_bound(|mut b| { assert_eq!(b.projection_ty.self_ty(), dummy_self); @@ -1600,8 +1642,8 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { fn report_ambiguous_associated_type( &self, span: Span, - type_str: &str, - trait_str: &str, + types: &[String], + traits: &[String], name: Symbol, ) -> ErrorGuaranteed { let mut err = struct_span_err!(self.tcx().sess, span, E0223, "ambiguous associated type"); @@ -1612,19 +1654,92 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { .keys() .any(|full_span| full_span.contains(span)) { - err.span_suggestion( + err.span_suggestion_verbose( span.shrink_to_lo(), "you are looking for the module in `std`, not the primitive type", "std::", Applicability::MachineApplicable, ); } else { - err.span_suggestion( - span, - "use fully-qualified syntax", - format!("<{} as {}>::{}", type_str, trait_str, name), - Applicability::HasPlaceholders, - ); + match (types, traits) { + ([], []) => { + err.span_suggestion_verbose( + span, + &format!( + "if there were a type named `Type` that implements a trait named \ + `Trait` with associated type `{name}`, you could use the \ + fully-qualified path", + ), + format!("<Type as Trait>::{name}"), + Applicability::HasPlaceholders, + ); + } + ([], [trait_str]) => { + err.span_suggestion_verbose( + span, + &format!( + "if there were a type named `Example` that implemented `{trait_str}`, \ + you could use the fully-qualified path", + ), + format!("<Example as {trait_str}>::{name}"), + Applicability::HasPlaceholders, + ); + } + ([], traits) => { + err.span_suggestions( + span, + &format!( + "if there were a type named `Example` that implemented one of the \ + traits with associated type `{name}`, you could use the \ + fully-qualified path", + ), + traits + .iter() + .map(|trait_str| format!("<Example as {trait_str}>::{name}")) + .collect::<Vec<_>>(), + Applicability::HasPlaceholders, + ); + } + ([type_str], []) => { + err.span_suggestion_verbose( + span, + &format!( + "if there were a trait named `Example` with associated type `{name}` \ + implemented for `{type_str}`, you could use the fully-qualified path", + ), + format!("<{type_str} as Example>::{name}"), + Applicability::HasPlaceholders, + ); + } + (types, []) => { + err.span_suggestions( + span, + &format!( + "if there were a trait named `Example` with associated type `{name}` \ + implemented for one of the types, you could use the fully-qualified \ + path", + ), + types + .into_iter() + .map(|type_str| format!("<{type_str} as Example>::{name}")), + Applicability::HasPlaceholders, + ); + } + (types, traits) => { + let mut suggestions = vec![]; + for type_str in types { + for trait_str in traits { + suggestions.push(format!("<{type_str} as {trait_str}>::{name}")); + } + } + err.span_suggestions( + span, + "use the fully-qualified path", + suggestions, + Applicability::MachineApplicable, + ); + } + } } err.emit() } @@ -1793,7 +1908,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { Ok(bound) } - // Create a type from a path to an associated type. + // Create a type from a path to an associated type or to an enum variant. // For a path `A::B::C::D`, `qself_ty` and `qself_def` are the type and def for `A::B::C` // and item_segment is the path segment for `D`. We return a type and a def for // the whole path. @@ -1813,7 +1928,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ) -> Result<(Ty<'tcx>, DefKind, DefId), ErrorGuaranteed> { let tcx = self.tcx(); let assoc_ident = assoc_segment.ident; - let qself_res = if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = qself.kind { + let qself_res = if let hir::TyKind::Path(hir::QPath::Resolved(_, path)) = &qself.kind { path.res } else { Res::Err @@ -1821,7 +1936,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // Check if we have an enum variant. let mut variant_resolution = None; - if let ty::Adt(adt_def, adt_substs) = qself_ty.kind() { + if let Some(adt_def) = self.probe_adt(span, qself_ty) { if adt_def.is_enum() { let variant_def = adt_def .variants() @@ -1856,8 +1971,8 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { return; }; let (qself_sugg_span, is_self) = if let hir::TyKind::Path( - hir::QPath::Resolved(_, ref path) - ) = qself.kind { + hir::QPath::Resolved(_, path) + ) = &qself.kind { // If the path segment already has type params, we want to overwrite // them. match &path.segments[..] { @@ -1923,6 +2038,10 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let Some(assoc_ty_did) = self.lookup_assoc_ty(assoc_ident, hir_ref_id, span, impl_) else { continue; }; + let ty::Adt(_, adt_substs) = qself_ty.kind() else { + // FIXME(inherent_associated_types) + bug!("unimplemented: non-adt self of inherent assoc ty"); + }; let item_substs = self.create_substs_for_associated_item( span, assoc_ty_did, @@ -1930,7 +2049,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { adt_substs, ); let ty = tcx.bound_type_of(assoc_ty_did).subst(tcx, item_substs); - let ty = self.normalize_ty(span, ty); return Ok((ty, DefKind::AssocTy, assoc_ty_did)); } } @@ -1948,7 +2066,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { }; self.one_bound_for_assoc_type( - || traits::supertraits(tcx, ty::Binder::dummy(trait_ref)), + || traits::supertraits(tcx, ty::Binder::dummy(trait_ref.subst_identity())), || "Self".to_string(), assoc_ident, span, @@ -2004,12 +2122,64 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { err.emit() } else if let Err(reported) = qself_ty.error_reported() { reported + } else if let ty::Alias(ty::Opaque, alias_ty) = qself_ty.kind() { + // `<impl Trait as OtherTrait>::Assoc` makes no sense. + struct_span_err!( + tcx.sess, + tcx.def_span(alias_ty.def_id), + E0667, + "`impl Trait` is not allowed in path parameters" + ) + .emit() // Already reported in an earlier stage. } else { + // Find all the `impl`s that `qself_ty` has for any trait that has the + // associated type, so that we suggest the right one. + let infcx = tcx.infer_ctxt().build(); + // We create a fresh `ty::ParamEnv` instead of the one for `self.item_def_id()` + // to avoid a cycle error in `src/test/ui/resolve/issue-102946.rs`. + let param_env = ty::ParamEnv::empty(); + let traits: Vec<_> = self + .tcx() + .all_traits() + .filter(|trait_def_id| { + // Consider only traits with the associated type + tcx.associated_items(*trait_def_id) + .in_definition_order() + .any(|i| { + i.kind.namespace() == Namespace::TypeNS + && i.ident(tcx).normalize_to_macros_2_0() == assoc_ident + && matches!(i.kind, ty::AssocKind::Type) + }) + // Consider only accessible traits + && tcx.visibility(*trait_def_id) + .is_accessible_from(self.item_def_id(), tcx) + && tcx.all_impls(*trait_def_id) + .any(|impl_def_id| { + let trait_ref = tcx.impl_trait_ref(impl_def_id); + trait_ref.map_or(false, |trait_ref| { + let impl_ = trait_ref.subst( + tcx, + infcx.fresh_substs_for_item(span, impl_def_id), + ); + infcx + .can_eq( + param_env, + tcx.erase_regions(impl_.self_ty()), + tcx.erase_regions(qself_ty), + ) + .is_ok() + }) + && tcx.impl_polarity(impl_def_id) != ty::ImplPolarity::Negative + }) + }) + .map(|trait_def_id| tcx.def_path_str(trait_def_id)) + .collect(); + // Don't print `TyErr` to the user. self.report_ambiguous_associated_type( span, - &qself_ty.to_string(), - "Trait", + &[qself_ty.to_string()], + &traits, assoc_ident.name, ) }; @@ -2027,7 +2197,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { }; let ty = self.projected_ty_from_poly_trait_ref(span, assoc_ty_did, assoc_segment, bound); - let ty = self.normalize_ty(span, ty); if let Some(variant_def_id) = variant_resolution { tcx.struct_span_lint_hir( @@ -2128,16 +2297,30 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let is_part_of_self_trait_constraints = def_id == trait_def_id; let is_part_of_fn_in_self_trait = parent_def_id == Some(trait_def_id); - let type_name = if is_part_of_self_trait_constraints || is_part_of_fn_in_self_trait { - "Self" + let type_names = if is_part_of_self_trait_constraints || is_part_of_fn_in_self_trait { + vec!["Self".to_string()] } else { - "Type" + // Find all the types that have an `impl` for the trait. + tcx.all_impls(trait_def_id) + .filter(|impl_def_id| { + // Consider only accessible traits + tcx.visibility(*impl_def_id).is_accessible_from(self.item_def_id(), tcx) + && tcx.impl_polarity(impl_def_id) != ty::ImplPolarity::Negative + }) + .filter_map(|impl_def_id| tcx.impl_trait_ref(impl_def_id)) + .map(|impl_| impl_.subst_identity().self_ty()) + // We don't care about blanket impls. + .filter(|self_ty| !self_ty.has_non_region_param()) + .map(|self_ty| tcx.erase_regions(self_ty).to_string()) + .collect() }; - + // FIXME: also look at `tcx.generics_of(self.item_def_id()).params` any that + // references the trait. Relevant for the first case in + // `src/test/ui/associated-types/associated-types-in-ambiguous-context.rs` let reported = self.report_ambiguous_associated_type( span, - type_name, - &path_str, + &type_names, + &[path_str], item_segment.ident.name, ); return tcx.ty_error_with_guaranteed(reported) @@ -2163,7 +2346,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { debug!("qpath_to_ty: trait_ref={:?}", trait_ref); - self.normalize_ty(span, tcx.mk_projection(item_def_id, item_substs)) + tcx.mk_projection(item_def_id, item_substs) } pub fn prohibit_generics<'a>( @@ -2243,7 +2426,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ), "s", ), - [only] => (format!("{only}"), ""), + [only] => (only.to_string(), ""), [] => unreachable!(), }; let last_span = *arg_spans.last().unwrap(); @@ -2266,7 +2449,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { for segment in segments { // Only emit the first error to avoid overloading the user with error messages. if let Some(b) = segment.args().bindings.first() { - Self::prohibit_assoc_ty_binding(self.tcx(), b.span); + prohibit_assoc_ty_binding(self.tcx(), b.span); return true; } } @@ -2280,6 +2463,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { self_ty: Option<Ty<'tcx>>, kind: DefKind, def_id: DefId, + span: Span, ) -> Vec<PathSeg> { // We need to extract the type parameters supplied by the user in // the path `path`. Due to the current setup, this is a bit of a @@ -2347,8 +2531,8 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // Case 2. Reference to a variant constructor. DefKind::Ctor(CtorOf::Variant, ..) | DefKind::Variant => { - let adt_def = self_ty.map(|t| t.ty_adt_def().unwrap()); - let (generics_def_id, index) = if let Some(adt_def) = adt_def { + let (generics_def_id, index) = if let Some(self_ty) = self_ty { + let adt_def = self.probe_adt(span, self_ty).unwrap(); debug_assert!(adt_def.is_enum()); (adt_def.did(), last) } else if last >= 1 && segments[last - 1].args.is_some() { @@ -2424,7 +2608,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { err.note("`impl Trait` types can't have type parameters"); }); let substs = self.ast_path_substs_for_ty(span, did, item_segment.0); - self.normalize_ty(span, tcx.mk_opaque(did, substs)) + tcx.mk_opaque(did, substs) } Res::Def( DefKind::Enum @@ -2444,7 +2628,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { assert_eq!(opt_self_ty, None); let path_segs = - self.def_ids_for_value_path_segments(path.segments, None, kind, def_id); + self.def_ids_for_value_path_segments(path.segments, None, kind, def_id, span); let generic_segs: FxHashSet<_> = path_segs.iter().map(|PathSeg(_, index)| index).collect(); self.prohibit_generics( @@ -2576,7 +2760,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { "generic `Self` types are currently not permitted in anonymous constants", ); if let Some(hir::Node::Item(&hir::Item { - kind: hir::ItemKind::Impl(ref impl_), + kind: hir::ItemKind::Impl(impl_), .. })) = tcx.hir().get_if_local(def_id) { @@ -2584,7 +2768,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } tcx.ty_error_with_guaranteed(err.emit()) } else { - self.normalize_ty(span, ty) + ty } } Res::Def(DefKind::AssocTy, def_id) => { @@ -2633,7 +2817,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let e = self .tcx() .sess - .delay_span_bug(path.span, "path with `Res:Err` but no error emitted"); + .delay_span_bug(path.span, "path with `Res::Err` but no error emitted"); self.set_tainted_by_errors(e); self.tcx().ty_error_with_guaranteed(e) } @@ -2648,7 +2832,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } /// Parses the programmer's textual representation of a type into our - /// internal notion of a type. This is meant to be used within a path. + /// internal notion of a type. This is meant to be used within a path. pub fn ast_ty_to_ty_in_path(&self, ast_ty: &hir::Ty<'_>) -> Ty<'tcx> { self.ast_ty_to_ty_inner(ast_ty, false, true) } @@ -2659,12 +2843,12 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { fn ast_ty_to_ty_inner(&self, ast_ty: &hir::Ty<'_>, borrowed: bool, in_path: bool) -> Ty<'tcx> { let tcx = self.tcx(); - let result_ty = match ast_ty.kind { - hir::TyKind::Slice(ref ty) => tcx.mk_slice(self.ast_ty_to_ty(ty)), - hir::TyKind::Ptr(ref mt) => { + let result_ty = match &ast_ty.kind { + hir::TyKind::Slice(ty) => tcx.mk_slice(self.ast_ty_to_ty(ty)), + hir::TyKind::Ptr(mt) => { tcx.mk_ptr(ty::TypeAndMut { ty: self.ast_ty_to_ty(mt.ty), mutbl: mt.mutbl }) } - hir::TyKind::Rptr(ref region, ref mt) => { + hir::TyKind::Ref(region, mt) => { let r = self.ast_region_to_region(region, None); debug!(?r); let t = self.ast_ty_to_ty_inner(mt.ty, true, false); @@ -2684,7 +2868,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { Some(ast_ty), )) } - hir::TyKind::TraitObject(bounds, ref lifetime, repr) => { + hir::TyKind::TraitObject(bounds, lifetime, repr) => { self.maybe_lint_bare_trait(ast_ty, in_path); let repr = match repr { TraitObjectSyntax::Dyn | TraitObjectSyntax::None => ty::Dyn, @@ -2692,12 +2876,12 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { }; self.conv_object_ty_poly_trait_ref(ast_ty.span, bounds, lifetime, borrowed, repr) } - hir::TyKind::Path(hir::QPath::Resolved(ref maybe_qself, ref path)) => { + hir::TyKind::Path(hir::QPath::Resolved(maybe_qself, path)) => { debug!(?maybe_qself, ?path); let opt_self_ty = maybe_qself.as_ref().map(|qself| self.ast_ty_to_ty(qself)); self.res_to_ty(opt_self_ty, path, false) } - hir::TyKind::OpaqueDef(item_id, lifetimes, in_trait) => { + &hir::TyKind::OpaqueDef(item_id, lifetimes, in_trait) => { let opaque_ty = tcx.hir().item(item_id); let def_id = item_id.owner_id.to_def_id(); @@ -2708,14 +2892,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ref i => bug!("`impl Trait` pointed to non-opaque type?? {:#?}", i), } } - hir::TyKind::Path(hir::QPath::TypeRelative(ref qself, ref segment)) => { + hir::TyKind::Path(hir::QPath::TypeRelative(qself, segment)) => { debug!(?qself, ?segment); let ty = self.ast_ty_to_ty_inner(qself, false, true); self.associated_path_to_ty(ast_ty.hir_id, ast_ty.span, ty, qself, segment, false) .map(|(ty, _, _)| ty) .unwrap_or_else(|_| tcx.ty_error()) } - hir::TyKind::Path(hir::QPath::LangItem(lang_item, span, _)) => { + &hir::TyKind::Path(hir::QPath::LangItem(lang_item, span, _)) => { let def_id = tcx.require_lang_item(lang_item, Some(span)); let (substs, _) = self.create_substs_for_ast_path( span, @@ -2727,10 +2911,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { None, ty::BoundConstness::NotConst, ); - EarlyBinder(self.normalize_ty(span, tcx.at(span).type_of(def_id))) - .subst(tcx, substs) + EarlyBinder(tcx.at(span).type_of(def_id)).subst(tcx, substs) } - hir::TyKind::Array(ref ty, ref length) => { + hir::TyKind::Array(ty, length) => { let length = match length { &hir::ArrayLen::Infer(_, span) => self.ct_infer(tcx.types.usize, None, span), hir::ArrayLen::Body(constant) => { @@ -2738,10 +2921,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } }; - let array_ty = tcx.mk_ty(ty::Array(self.ast_ty_to_ty(ty), length)); - self.normalize_ty(ast_ty.span, array_ty) + tcx.mk_ty(ty::Array(self.ast_ty_to_ty(ty), length)) } - hir::TyKind::Typeof(ref e) => { + hir::TyKind::Typeof(e) => { let ty_erased = tcx.type_of(e.def_id); let ty = tcx.fold_regions(ty_erased, |r, _| { if r.is_erased() { tcx.lifetimes.re_static } else { r } @@ -2943,7 +3125,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let hir::Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Fn(..), ident, .. }) = hir.get(fn_hir_id) else { return None }; let hir::Node::Item(hir::Item { kind: hir::ItemKind::Impl(i), .. }) = - hir.get(hir.get_parent_node(fn_hir_id)) else { bug!("ImplItem should have Impl parent") }; + hir.get_parent(fn_hir_id) else { bug!("ImplItem should have Impl parent") }; let trait_ref = self.instantiate_mono_trait_ref( i.of_trait.as_ref()?, @@ -3123,7 +3305,13 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let label = "add `dyn` keyword before this trait"; let mut diag = rustc_errors::struct_span_err!(tcx.sess, self_ty.span, E0782, "{}", msg); - diag.multipart_suggestion_verbose(label, sugg, Applicability::MachineApplicable); + if self_ty.span.can_be_used_for_suggestions() { + diag.multipart_suggestion_verbose( + label, + sugg, + Applicability::MachineApplicable, + ); + } // check if the impl trait that we are considering is a impl of a local trait self.maybe_lint_blanket_trait_impl(&self_ty, &mut diag); diag.emit(); |