diff options
Diffstat (limited to 'compiler/rustc_parse/src/parser/ty.rs')
| -rw-r--r-- | compiler/rustc_parse/src/parser/ty.rs | 182 |
1 files changed, 67 insertions, 115 deletions
diff --git a/compiler/rustc_parse/src/parser/ty.rs b/compiler/rustc_parse/src/parser/ty.rs index 867974672..6fe4da71f 100644 --- a/compiler/rustc_parse/src/parser/ty.rs +++ b/compiler/rustc_parse/src/parser/ty.rs @@ -1,6 +1,12 @@ use super::{Parser, PathStyle, TokenType}; -use crate::errors::{ExpectedFnPathFoundFnKeyword, FnPtrWithGenerics, FnPtrWithGenericsSugg}; +use crate::errors::{ + DynAfterMut, ExpectedFnPathFoundFnKeyword, ExpectedMutOrConstInRawPointerType, + FnPointerCannotBeAsync, FnPointerCannotBeConst, FnPtrWithGenerics, FnPtrWithGenericsSugg, + InvalidDynKeyword, LifetimeAfterMut, NeedPlusAfterTraitObjectLifetime, + NegativeBoundsNotSupported, NegativeBoundsNotSupportedSugg, NestedCVariadicType, + ReturnTypesUseThinArrow, +}; use crate::{maybe_recover_from_interpolated_ty_qpath, maybe_whole}; use ast::DUMMY_NODE_ID; @@ -11,11 +17,11 @@ use rustc_ast::{ self as ast, BareFnTy, FnRetTy, GenericBound, GenericBounds, GenericParam, Generics, Lifetime, MacCall, MutTy, Mutability, PolyTraitRef, TraitBoundModifier, TraitObjectSyntax, Ty, TyKind, }; -use rustc_errors::{pluralize, struct_span_err, Applicability, PResult}; +use rustc_errors::{Applicability, PResult}; use rustc_span::source_map::Span; use rustc_span::symbol::{kw, sym, Ident}; use rustc_span::Symbol; -use thin_vec::thin_vec; +use thin_vec::{thin_vec, ThinVec}; /// Any `?` or `~const` modifiers that appear at the start of a bound. struct BoundModifiers { @@ -217,14 +223,7 @@ impl<'a> Parser<'a> { // Don't `eat` to prevent `=>` from being added as an expected token which isn't // actually expected and could only confuse users self.bump(); - self.struct_span_err(self.prev_token.span, "return types are denoted using `->`") - .span_suggestion_short( - self.prev_token.span, - "use `->` instead", - "->", - Applicability::MachineApplicable, - ) - .emit(); + self.sess.emit_err(ReturnTypesUseThinArrow { span: self.prev_token.span }); let ty = self.parse_ty_common( allow_plus, AllowCVariadic::No, @@ -274,7 +273,7 @@ impl<'a> Parser<'a> { TyKind::Infer } else if self.check_fn_front_matter(false, Case::Sensitive) { // Function pointer type - self.parse_ty_bare_fn(lo, Vec::new(), None, recover_return_sign)? + self.parse_ty_bare_fn(lo, ThinVec::new(), None, recover_return_sign)? } else if self.check_keyword(kw::For) { // Function pointer type or bound list (trait object type) starting with a poly-trait. // `for<'lt> [unsafe] [extern "ABI"] fn (&'lt S) -> T` @@ -305,13 +304,14 @@ impl<'a> Parser<'a> { } else if self.can_begin_bound() { self.parse_bare_trait_object(lo, allow_plus)? } else if self.eat(&token::DotDotDot) { - if allow_c_variadic == AllowCVariadic::Yes { - TyKind::CVarArgs - } else { - // FIXME(Centril): Should we just allow `...` syntactically - // anywhere in a type and use semantic restrictions instead? - self.error_illegal_c_varadic_ty(lo); - TyKind::Err + match allow_c_variadic { + AllowCVariadic::Yes => TyKind::CVarArgs, + AllowCVariadic::No => { + // FIXME(Centril): Should we just allow `...` syntactically + // anywhere in a type and use semantic restrictions instead? + self.sess.emit_err(NestedCVariadicType { span: lo.to(self.prev_token.span) }); + TyKind::Err + } } } else { let msg = format!("expected type, found {}", super::token_descr(&self.token)); @@ -325,10 +325,9 @@ impl<'a> Parser<'a> { let mut ty = self.mk_ty(span, kind); // Try to recover from use of `+` with incorrect priority. - if matches!(allow_plus, AllowPlus::Yes) { - self.maybe_recover_from_bad_type_plus(&ty)?; - } else { - self.maybe_report_ambiguous_plus(impl_dyn_multi, &ty); + match allow_plus { + AllowPlus::Yes => self.maybe_recover_from_bad_type_plus(&ty)?, + AllowPlus::No => self.maybe_report_ambiguous_plus(impl_dyn_multi, &ty), } if let RecoverQuestionMark::Yes = recover_question_mark { ty = self.maybe_recover_from_question_mark(ty); @@ -353,7 +352,7 @@ impl<'a> Parser<'a> { match ty.kind { // `(TY_BOUND_NOPAREN) + BOUND + ...`. TyKind::Path(None, path) if maybe_bounds => { - self.parse_remaining_bounds_path(Vec::new(), path, lo, true) + self.parse_remaining_bounds_path(ThinVec::new(), path, lo, true) } TyKind::TraitObject(bounds, TraitObjectSyntax::None) if maybe_bounds && bounds.len() == 1 && !trailing_plus => @@ -372,15 +371,14 @@ impl<'a> Parser<'a> { let lt_no_plus = self.check_lifetime() && !self.look_ahead(1, |t| t.is_like_plus()); let bounds = self.parse_generic_bounds_common(allow_plus, None)?; if lt_no_plus { - self.struct_span_err(lo, "lifetime in trait object type must be followed by `+`") - .emit(); + self.sess.emit_err(NeedPlusAfterTraitObjectLifetime { span: lo }); } Ok(TyKind::TraitObject(bounds, TraitObjectSyntax::None)) } fn parse_remaining_bounds_path( &mut self, - generic_params: Vec<GenericParam>, + generic_params: ThinVec<GenericParam>, path: ast::Path, lo: Span, parse_plus: bool, @@ -407,14 +405,10 @@ impl<'a> Parser<'a> { fn parse_ty_ptr(&mut self) -> PResult<'a, TyKind> { let mutbl = self.parse_const_or_mut().unwrap_or_else(|| { let span = self.prev_token.span; - self.struct_span_err(span, "expected `mut` or `const` keyword in raw pointer type") - .span_suggestions( - span.shrink_to_hi(), - "add `mut` or `const` here", - ["mut ".to_string(), "const ".to_string()], - Applicability::HasPlaceholders, - ) - .emit(); + self.sess.emit_err(ExpectedMutOrConstInRawPointerType { + span, + after_asterisk: span.shrink_to_hi(), + }); Mutability::Not }); let ty = self.parse_ty_no_plus()?; @@ -439,7 +433,7 @@ impl<'a> Parser<'a> { }; let ty = if self.eat(&token::Semi) { - let mut length = self.parse_anon_const_expr()?; + let mut length = self.parse_expr_anon_const()?; if let Err(e) = self.expect(&token::CloseDelim(Delimiter::Bracket)) { // Try to recover from `X<Y, ...>` when `X::<Y, ...>` works self.check_mistyped_turbofish_with_multiple_type_params(e, &mut length.value)?; @@ -456,8 +450,7 @@ impl<'a> Parser<'a> { fn parse_borrowed_pointee(&mut self) -> PResult<'a, TyKind> { let and_span = self.prev_token.span; - let mut opt_lifetime = - if self.check_lifetime() { Some(self.expect_lifetime()) } else { None }; + let mut opt_lifetime = self.check_lifetime().then(|| self.expect_lifetime()); let mut mutbl = self.parse_mutability(); if self.token.is_lifetime() && mutbl == Mutability::Mut && opt_lifetime.is_none() { // A lifetime is invalid here: it would be part of a bare trait bound, which requires @@ -469,16 +462,13 @@ impl<'a> Parser<'a> { let lifetime_span = self.token.span; let span = and_span.to(lifetime_span); - let mut err = self.struct_span_err(span, "lifetime must precede `mut`"); - if let Ok(lifetime_src) = self.span_to_snippet(lifetime_span) { - err.span_suggestion( - span, - "place the lifetime before `mut`", - format!("&{} mut", lifetime_src), - Applicability::MaybeIncorrect, - ); - } - err.emit(); + let (suggest_lifetime, snippet) = + if let Ok(lifetime_src) = self.span_to_snippet(lifetime_span) { + (Some(span), lifetime_src) + } else { + (None, String::new()) + }; + self.sess.emit_err(LifetimeAfterMut { span, suggest_lifetime, snippet }); opt_lifetime = Some(self.expect_lifetime()); } @@ -488,14 +478,7 @@ impl<'a> Parser<'a> { { // We have `&dyn mut ...`, which is invalid and should be `&mut dyn ...`. let span = and_span.to(self.look_ahead(1, |t| t.span)); - let mut err = self.struct_span_err(span, "`mut` must precede `dyn`"); - err.span_suggestion( - span, - "place `mut` before `dyn`", - "&mut dyn", - Applicability::MachineApplicable, - ); - err.emit(); + self.sess.emit_err(DynAfterMut { span }); // Recovery mutbl = Mutability::Mut; @@ -511,7 +494,7 @@ impl<'a> Parser<'a> { // To avoid ambiguity, the type is surrounded by parentheses. fn parse_typeof_ty(&mut self) -> PResult<'a, TyKind> { self.expect(&token::OpenDelim(Delimiter::Parenthesis))?; - let expr = self.parse_anon_const_expr()?; + let expr = self.parse_expr_anon_const()?; self.expect(&token::CloseDelim(Delimiter::Parenthesis))?; Ok(TyKind::Typeof(expr)) } @@ -528,7 +511,7 @@ impl<'a> Parser<'a> { fn parse_ty_bare_fn( &mut self, lo: Span, - mut params: Vec<GenericParam>, + mut params: ThinVec<GenericParam>, param_insertion_point: Option<Span>, recover_return_sign: RecoverReturnSign, ) -> PResult<'a, TyKind> { @@ -549,10 +532,10 @@ impl<'a> Parser<'a> { // If we ever start to allow `const fn()`, then update // feature gating for `#![feature(const_extern_fn)]` to // cover it. - self.error_fn_ptr_bad_qualifier(whole_span, span, "const"); + self.sess.emit_err(FnPointerCannotBeConst { span: whole_span, qualifier: span }); } if let ast::Async::Yes { span, .. } = asyncness { - self.error_fn_ptr_bad_qualifier(whole_span, span, "async"); + self.sess.emit_err(FnPointerCannotBeAsync { span: whole_span, qualifier: span }); } let decl_span = span_start.to(self.token.span); Ok(TyKind::BareFn(P(BareFnTy { ext, unsafety, generic_params: params, decl, decl_span }))) @@ -562,13 +545,13 @@ impl<'a> Parser<'a> { fn recover_fn_ptr_with_generics( &mut self, lo: Span, - params: &mut Vec<GenericParam>, + params: &mut ThinVec<GenericParam>, param_insertion_point: Option<Span>, ) -> PResult<'a, ()> { let generics = self.parse_generics()?; let arity = generics.params.len(); - let mut lifetimes: Vec<_> = generics + let mut lifetimes: ThinVec<_> = generics .params .into_iter() .filter(|param| matches!(param.kind, ast::GenericParamKind::Lifetime)) @@ -600,19 +583,6 @@ impl<'a> Parser<'a> { Ok(()) } - /// Emit an error for the given bad function pointer qualifier. - fn error_fn_ptr_bad_qualifier(&self, span: Span, qual_span: Span, qual: &str) { - self.struct_span_err(span, &format!("an `fn` pointer type cannot be `{}`", qual)) - .span_label(qual_span, format!("`{}` because of this", qual)) - .span_suggestion_short( - qual_span, - &format!("remove the `{}` qualifier", qual), - "", - Applicability::MaybeIncorrect, - ) - .emit(); - } - /// Parses an `impl B0 + ... + Bn` type. fn parse_impl_ty(&mut self, impl_dyn_multi: &mut bool) -> PResult<'a, TyKind> { // Always parse bounds greedily for better error recovery. @@ -643,7 +613,7 @@ impl<'a> Parser<'a> { /// Is a `dyn B0 + ... + Bn` type allowed here? fn is_explicit_dyn_type(&mut self) -> bool { self.check_keyword(kw::Dyn) - && (!self.token.uninterpolated_span().rust_2015() + && (self.token.uninterpolated_span().rust_2018() || self.look_ahead(1, |t| { (t.can_begin_bound() || t.kind == TokenKind::BinOp(token::Star)) && !can_continue_type_after_non_fn_ident(t) @@ -692,23 +662,13 @@ impl<'a> Parser<'a> { }))) } else if allow_plus == AllowPlus::Yes && self.check_plus() { // `Trait1 + Trait2 + 'a` - self.parse_remaining_bounds_path(Vec::new(), path, lo, true) + self.parse_remaining_bounds_path(ThinVec::new(), path, lo, true) } else { // Just a type path. Ok(TyKind::Path(None, path)) } } - fn error_illegal_c_varadic_ty(&self, lo: Span) { - struct_span_err!( - self.sess.span_diagnostic, - lo.to(self.prev_token.span), - E0743, - "C-variadic type `...` may not be nested inside another type", - ) - .emit(); - } - pub(super) fn parse_generic_bounds( &mut self, colon_span: Option<Span>, @@ -739,15 +699,7 @@ impl<'a> Parser<'a> { { if self.token.is_keyword(kw::Dyn) { // Account for `&dyn Trait + dyn Other`. - self.struct_span_err(self.token.span, "invalid `dyn` keyword") - .help("`dyn` is only needed at the start of a trait `+`-separated list") - .span_suggestion( - self.token.span, - "remove this keyword", - "", - Applicability::MachineApplicable, - ) - .emit(); + self.sess.emit_err(InvalidDynKeyword { span: self.token.span }); self.bump(); } match self.parse_generic_bound()? { @@ -784,11 +736,7 @@ impl<'a> Parser<'a> { bounds: &[GenericBound], negative_bounds: Vec<Span>, ) { - let negative_bounds_len = negative_bounds.len(); - let last_span = *negative_bounds.last().expect("no negative bounds, but still error?"); - let mut err = self.struct_span_err(negative_bounds, "negative bounds are not supported"); - err.span_label(last_span, "negative bounds are not supported"); - if let Some(bound_list) = colon_span { + let sub = if let Some(bound_list) = colon_span { let bound_list = bound_list.to(self.prev_token.span); let mut new_bound_list = String::new(); if !bounds.is_empty() { @@ -799,14 +747,18 @@ impl<'a> Parser<'a> { } new_bound_list = new_bound_list.replacen(" +", ":", 1); } - err.tool_only_span_suggestion( + + Some(NegativeBoundsNotSupportedSugg { bound_list, - &format!("remove the bound{}", pluralize!(negative_bounds_len)), - new_bound_list, - Applicability::MachineApplicable, - ); - } - err.emit(); + num_bounds: negative_bounds.len(), + fixed: new_bound_list, + }) + } else { + None + }; + + let last_span = *negative_bounds.last().expect("no negative bounds, but still error?"); + self.sess.emit_err(NegativeBoundsNotSupported { negative_bounds, last_span, sub }); } /// Parses a bound according to the grammar: @@ -918,7 +870,7 @@ impl<'a> Parser<'a> { None }; - let maybe = if self.eat(&token::Question) { Some(self.prev_token.span) } else { None }; + let maybe = self.eat(&token::Question).then_some(self.prev_token.span); Ok(BoundModifiers { maybe, maybe_const }) } @@ -990,7 +942,7 @@ impl<'a> Parser<'a> { self.parse_remaining_bounds(bounds, true)?; self.expect(&token::CloseDelim(Delimiter::Parenthesis))?; let sp = vec![lo, self.prev_token.span]; - let sugg: Vec<_> = sp.iter().map(|sp| (*sp, String::new())).collect(); + let sugg = vec![(lo, String::from(" ")), (self.prev_token.span, String::new())]; self.struct_span_err(sp, "incorrect braces around trait bounds") .multipart_suggestion( "remove the parentheses", @@ -1041,7 +993,7 @@ impl<'a> Parser<'a> { } /// Optionally parses `for<$generic_params>`. - pub(super) fn parse_late_bound_lifetime_defs(&mut self) -> PResult<'a, Vec<GenericParam>> { + pub(super) fn parse_late_bound_lifetime_defs(&mut self) -> PResult<'a, ThinVec<GenericParam>> { if self.eat_keyword(kw::For) { self.expect_lt()?; let params = self.parse_generic_params()?; @@ -1050,7 +1002,7 @@ impl<'a> Parser<'a> { // parameters, and the lifetime parameters must not have bounds. Ok(params) } else { - Ok(Vec::new()) + Ok(ThinVec::new()) } } @@ -1060,7 +1012,7 @@ impl<'a> Parser<'a> { fn recover_fn_trait_with_lifetime_params( &mut self, fn_path: &mut ast::Path, - lifetime_defs: &mut Vec<GenericParam>, + lifetime_defs: &mut ThinVec<GenericParam>, ) -> PResult<'a, ()> { let fn_path_segment = fn_path.segments.last_mut().unwrap(); let generic_args = if let Some(p_args) = &fn_path_segment.args { @@ -1094,7 +1046,7 @@ impl<'a> Parser<'a> { // Parse `(T, U) -> R`. let inputs_lo = self.token.span; - let inputs: Vec<_> = + let inputs: ThinVec<_> = self.parse_fn_params(|_| false)?.into_iter().map(|input| input.ty).collect(); let inputs_span = inputs_lo.to(self.prev_token.span); let output = self.parse_ret_ty(AllowPlus::No, RecoverQPath::No, RecoverReturnSign::No)?; @@ -1120,7 +1072,7 @@ impl<'a> Parser<'a> { kind: ast::GenericParamKind::Lifetime, colon_span: None, }) - .collect::<Vec<GenericParam>>(); + .collect::<ThinVec<GenericParam>>(); lifetime_defs.append(&mut generic_params); let generic_args_span = generic_args.span(); |