diff options
Diffstat (limited to 'compiler/rustc_parse/src')
| -rw-r--r-- | compiler/rustc_parse/src/errors.rs | 38 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/lexer/mod.rs | 3 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/lib.rs | 16 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/attr.rs | 3 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/cfg_select.rs | 30 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/diagnostics.rs | 23 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/expr.rs | 12 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/generics.rs | 11 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/item.rs | 70 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/mod.rs | 25 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/pat.rs | 18 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/path.rs | 12 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/stmt.rs | 6 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/ty.rs | 161 |
14 files changed, 266 insertions, 162 deletions
diff --git a/compiler/rustc_parse/src/errors.rs b/compiler/rustc_parse/src/errors.rs index a07d0606fd0..2c046329e33 100644 --- a/compiler/rustc_parse/src/errors.rs +++ b/compiler/rustc_parse/src/errors.rs @@ -2661,7 +2661,7 @@ pub(crate) enum TopLevelOrPatternNotAllowedSugg { parse_sugg_remove_leading_vert_in_pattern, code = "", applicability = "machine-applicable", - style = "verbose" + style = "tool-only" )] RemoveLeadingVert { #[primary_span] @@ -2694,12 +2694,25 @@ pub(crate) struct UnexpectedVertVertInPattern { pub start: Option<Span>, } +#[derive(Subdiagnostic)] +#[suggestion( + parse_trailing_vert_not_allowed, + code = "", + applicability = "machine-applicable", + style = "tool-only" +)] +pub(crate) struct TrailingVertSuggestion { + #[primary_span] + pub span: Span, +} + #[derive(Diagnostic)] #[diag(parse_trailing_vert_not_allowed)] pub(crate) struct TrailingVertNotAllowed { #[primary_span] - #[suggestion(code = "", applicability = "machine-applicable", style = "verbose")] pub span: Span, + #[subdiagnostic] + pub suggestion: TrailingVertSuggestion, #[label(parse_label_while_parsing_or_pattern_here)] pub start: Option<Span>, pub token: Token, @@ -3150,27 +3163,6 @@ pub(crate) struct ModifierLifetime { pub modifier: &'static str, } -#[derive(Subdiagnostic)] -#[multipart_suggestion( - parse_parenthesized_lifetime_suggestion, - applicability = "machine-applicable" -)] -pub(crate) struct RemoveParens { - #[suggestion_part(code = "")] - pub lo: Span, - #[suggestion_part(code = "")] - pub hi: Span, -} - -#[derive(Diagnostic)] -#[diag(parse_parenthesized_lifetime)] -pub(crate) struct ParenthesizedLifetime { - #[primary_span] - pub span: Span, - #[subdiagnostic] - pub sugg: RemoveParens, -} - #[derive(Diagnostic)] #[diag(parse_underscore_literal_suffix)] pub(crate) struct UnderscoreLiteralSuffix { diff --git a/compiler/rustc_parse/src/lexer/mod.rs b/compiler/rustc_parse/src/lexer/mod.rs index 85af5a615ae..7c7e7e50b27 100644 --- a/compiler/rustc_parse/src/lexer/mod.rs +++ b/compiler/rustc_parse/src/lexer/mod.rs @@ -49,6 +49,7 @@ pub(crate) fn lex_token_trees<'psess, 'src>( mut src: &'src str, mut start_pos: BytePos, override_span: Option<Span>, + frontmatter_allowed: FrontmatterAllowed, ) -> Result<TokenStream, Vec<Diag<'psess>>> { // Skip `#!`, if present. if let Some(shebang_len) = rustc_lexer::strip_shebang(src) { @@ -56,7 +57,7 @@ pub(crate) fn lex_token_trees<'psess, 'src>( start_pos = start_pos + BytePos::from_usize(shebang_len); } - let cursor = Cursor::new(src, FrontmatterAllowed::Yes); + let cursor = Cursor::new(src, frontmatter_allowed); let mut lexer = Lexer { psess, start_pos, diff --git a/compiler/rustc_parse/src/lib.rs b/compiler/rustc_parse/src/lib.rs index 2050c5f9608..adad5751871 100644 --- a/compiler/rustc_parse/src/lib.rs +++ b/compiler/rustc_parse/src/lib.rs @@ -20,6 +20,7 @@ use rustc_ast::tokenstream::TokenStream; use rustc_ast::{AttrItem, Attribute, MetaItemInner, token}; use rustc_ast_pretty::pprust; use rustc_errors::{Diag, EmissionGuarantee, FatalError, PResult, pluralize}; +use rustc_lexer::FrontmatterAllowed; use rustc_session::parse::ParseSess; use rustc_span::source_map::SourceMap; use rustc_span::{FileName, SourceFile, Span}; @@ -146,7 +147,7 @@ fn new_parser_from_source_file( source_file: Arc<SourceFile>, ) -> Result<Parser<'_>, Vec<Diag<'_>>> { let end_pos = source_file.end_position(); - let stream = source_file_to_stream(psess, source_file, None)?; + let stream = source_file_to_stream(psess, source_file, None, FrontmatterAllowed::Yes)?; let mut parser = Parser::new(psess, stream, None); if parser.token == token::Eof { parser.token.span = Span::new(end_pos, end_pos, parser.token.span.ctxt(), None); @@ -161,7 +162,9 @@ pub fn source_str_to_stream( override_span: Option<Span>, ) -> Result<TokenStream, Vec<Diag<'_>>> { let source_file = psess.source_map().new_source_file(name, source); - source_file_to_stream(psess, source_file, override_span) + // used mainly for `proc_macro` and the likes, not for our parsing purposes, so don't parse + // frontmatters as frontmatters. + source_file_to_stream(psess, source_file, override_span, FrontmatterAllowed::No) } /// Given a source file, produces a sequence of token trees. Returns any buffered errors from @@ -170,6 +173,7 @@ fn source_file_to_stream<'psess>( psess: &'psess ParseSess, source_file: Arc<SourceFile>, override_span: Option<Span>, + frontmatter_allowed: FrontmatterAllowed, ) -> Result<TokenStream, Vec<Diag<'psess>>> { let src = source_file.src.as_ref().unwrap_or_else(|| { psess.dcx().bug(format!( @@ -178,7 +182,13 @@ fn source_file_to_stream<'psess>( )); }); - lexer::lex_token_trees(psess, src.as_str(), source_file.start_pos, override_span) + lexer::lex_token_trees( + psess, + src.as_str(), + source_file.start_pos, + override_span, + frontmatter_allowed, + ) } /// Runs the given subparser `f` on the tokens of the given `attr`'s item. diff --git a/compiler/rustc_parse/src/parser/attr.rs b/compiler/rustc_parse/src/parser/attr.rs index 41d3889c448..7f6afeba28c 100644 --- a/compiler/rustc_parse/src/parser/attr.rs +++ b/compiler/rustc_parse/src/parser/attr.rs @@ -11,6 +11,7 @@ use tracing::debug; use super::{ AttrWrapper, Capturing, FnParseMode, ForceCollect, Parser, PathStyle, Trailing, UsePreAttrPos, }; +use crate::parser::FnContext; use crate::{errors, exp, fluent_generated as fluent}; // Public for rustfmt usage @@ -200,7 +201,7 @@ impl<'a> Parser<'a> { AttrWrapper::empty(), true, false, - FnParseMode { req_name: |_| true, req_body: true }, + FnParseMode { req_name: |_| true, context: FnContext::Free, req_body: true }, ForceCollect::No, ) { Ok(Some(item)) => { diff --git a/compiler/rustc_parse/src/parser/cfg_select.rs b/compiler/rustc_parse/src/parser/cfg_select.rs index 2c6fb224d70..08a71db4de8 100644 --- a/compiler/rustc_parse/src/parser/cfg_select.rs +++ b/compiler/rustc_parse/src/parser/cfg_select.rs @@ -1,11 +1,12 @@ use rustc_ast::token::Token; use rustc_ast::tokenstream::{TokenStream, TokenTree}; +use rustc_ast::util::classify; use rustc_ast::{MetaItemInner, token}; use rustc_errors::PResult; use rustc_span::Span; use crate::exp; -use crate::parser::Parser; +use crate::parser::{AttrWrapper, ForceCollect, Parser, Restrictions, Trailing, UsePreAttrPos}; pub enum CfgSelectPredicate { Cfg(MetaItemInner), @@ -23,19 +24,26 @@ pub struct CfgSelectBranches { pub unreachable: Vec<(CfgSelectPredicate, TokenStream, Span)>, } -/// Parses a `TokenTree` that must be of the form `{ /* ... */ }`, and returns a `TokenStream` where -/// the surrounding braces are stripped. +/// Parses a `TokenTree` consisting either of `{ /* ... */ }` (and strip the braces) or an +/// expression followed by a comma (and strip the comma). fn parse_token_tree<'a>(p: &mut Parser<'a>) -> PResult<'a, TokenStream> { - // Generate an error if the `=>` is not followed by `{`. - if p.token != token::OpenBrace { - p.expect(exp!(OpenBrace))?; + if p.token == token::OpenBrace { + // Strip the outer '{' and '}'. + match p.parse_token_tree() { + TokenTree::Token(..) => unreachable!("because of the expect above"), + TokenTree::Delimited(.., tts) => return Ok(tts), + } } - - // Strip the outer '{' and '}'. - match p.parse_token_tree() { - TokenTree::Token(..) => unreachable!("because of the expect above"), - TokenTree::Delimited(.., tts) => Ok(tts), + let expr = p.collect_tokens(None, AttrWrapper::empty(), ForceCollect::Yes, |p, _| { + p.parse_expr_res(Restrictions::STMT_EXPR, AttrWrapper::empty()) + .map(|(expr, _)| (expr, Trailing::No, UsePreAttrPos::No)) + })?; + if !classify::expr_is_complete(&expr) && p.token != token::CloseBrace && p.token != token::Eof { + p.expect(exp!(Comma))?; + } else { + let _ = p.eat(exp!(Comma)); } + Ok(TokenStream::from_ast(&expr)) } pub fn parse_cfg_select<'a>(p: &mut Parser<'a>) -> PResult<'a, CfgSelectBranches> { diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs index a32cd33a260..220e4ac18fc 100644 --- a/compiler/rustc_parse/src/parser/diagnostics.rs +++ b/compiler/rustc_parse/src/parser/diagnostics.rs @@ -44,6 +44,7 @@ use crate::errors::{ UnexpectedConstParamDeclaration, UnexpectedConstParamDeclarationSugg, UnmatchedAngleBrackets, UseEqInstead, WrapType, }; +use crate::parser::FnContext; use crate::parser::attr::InnerAttrPolicy; use crate::{exp, fluent_generated as fluent}; @@ -2246,6 +2247,7 @@ impl<'a> Parser<'a> { pat: Box<ast::Pat>, require_name: bool, first_param: bool, + fn_parse_mode: &crate::parser::item::FnParseMode, ) -> Option<Ident> { // If we find a pattern followed by an identifier, it could be an (incorrect) // C-style parameter declaration. @@ -2268,7 +2270,14 @@ impl<'a> Parser<'a> { || self.token == token::Lt || self.token == token::CloseParen) { - let rfc_note = "anonymous parameters are removed in the 2018 edition (see RFC 1685)"; + let maybe_emit_anon_params_note = |this: &mut Self, err: &mut Diag<'_>| { + let ed = this.token.span.with_neighbor(this.prev_token.span).edition(); + if matches!(fn_parse_mode.context, crate::parser::item::FnContext::Trait) + && (fn_parse_mode.req_name)(ed) + { + err.note("anonymous parameters are removed in the 2018 edition (see RFC 1685)"); + } + }; let (ident, self_sugg, param_sugg, type_sugg, self_span, param_span, type_span) = match pat.kind { @@ -2305,7 +2314,7 @@ impl<'a> Parser<'a> { "_: ".to_string(), Applicability::MachineApplicable, ); - err.note(rfc_note); + maybe_emit_anon_params_note(self, err); } return None; @@ -2313,7 +2322,13 @@ impl<'a> Parser<'a> { }; // `fn foo(a, b) {}`, `fn foo(a<x>, b<y>) {}` or `fn foo(usize, usize) {}` - if first_param { + if first_param + // Only when the fn is a method, we emit this suggestion. + && matches!( + fn_parse_mode.context, + FnContext::Trait | FnContext::Impl + ) + { err.span_suggestion_verbose( self_span, "if this is a `self` type, give it a parameter name", @@ -2337,7 +2352,7 @@ impl<'a> Parser<'a> { type_sugg, Applicability::MachineApplicable, ); - err.note(rfc_note); + maybe_emit_anon_params_note(self, err); // Don't attempt to recover by using the `X` in `X<Y>` as the parameter name. return if self.token == token::Lt { None } else { Some(ident) }; diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index d0604f76317..cb7f755f524 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -2397,20 +2397,24 @@ impl<'a> Parser<'a> { let before = self.prev_token; let binder = if self.check_keyword(exp!(For)) { let lo = self.token.span; - let (lifetime_defs, _) = self.parse_late_bound_lifetime_defs()?; + let (bound_vars, _) = self.parse_higher_ranked_binder()?; let span = lo.to(self.prev_token.span); self.psess.gated_spans.gate(sym::closure_lifetime_binder, span); - ClosureBinder::For { span, generic_params: lifetime_defs } + ClosureBinder::For { span, generic_params: bound_vars } } else { ClosureBinder::NotPresent }; let constness = self.parse_closure_constness(); - let movability = - if self.eat_keyword(exp!(Static)) { Movability::Static } else { Movability::Movable }; + let movability = if self.eat_keyword(exp!(Static)) { + self.psess.gated_spans.gate(sym::coroutines, self.prev_token.span); + Movability::Static + } else { + Movability::Movable + }; let coroutine_kind = if self.token_uninterpolated_span().at_least_rust_2018() { self.parse_coroutine_kind(Case::Sensitive) diff --git a/compiler/rustc_parse/src/parser/generics.rs b/compiler/rustc_parse/src/parser/generics.rs index 4a8530a2b38..eb684c3a62f 100644 --- a/compiler/rustc_parse/src/parser/generics.rs +++ b/compiler/rustc_parse/src/parser/generics.rs @@ -172,8 +172,11 @@ impl<'a> Parser<'a> { }) } - /// Parses a (possibly empty) list of lifetime and type parameters, possibly including - /// a trailing comma and erroneous trailing attributes. + /// Parse a (possibly empty) list of generic (lifetime, type, const) parameters. + /// + /// ```ebnf + /// GenericParams = (GenericParam ("," GenericParam)* ","?)? + /// ``` pub(super) fn parse_generic_params(&mut self) -> PResult<'a, ThinVec<ast::GenericParam>> { let mut params = ThinVec::new(); let mut done = false; @@ -520,7 +523,7 @@ impl<'a> Parser<'a> { // * `for<'a> Trait1<'a>: Trait2<'a /* ok */>` // * `(for<'a> Trait1<'a>): Trait2<'a /* not ok */>` // * `for<'a> for<'b> Trait1<'a, 'b>: Trait2<'a /* ok */, 'b /* not ok */>` - let (lifetime_defs, _) = self.parse_late_bound_lifetime_defs()?; + let (bound_vars, _) = self.parse_higher_ranked_binder()?; // Parse type with mandatory colon and (possibly empty) bounds, // or with mandatory equality sign and the second type. @@ -528,7 +531,7 @@ impl<'a> Parser<'a> { if self.eat(exp!(Colon)) { let bounds = self.parse_generic_bounds()?; Ok(ast::WherePredicateKind::BoundPredicate(ast::WhereBoundPredicate { - bound_generic_params: lifetime_defs, + bound_generic_params: bound_vars, bounded_ty: ty, bounds, })) diff --git a/compiler/rustc_parse/src/parser/item.rs b/compiler/rustc_parse/src/parser/item.rs index 607adaf0829..fd9fb65417c 100644 --- a/compiler/rustc_parse/src/parser/item.rs +++ b/compiler/rustc_parse/src/parser/item.rs @@ -43,7 +43,7 @@ impl<'a> Parser<'a> { self.expect(exp!(OpenBrace))?; let (inner_attrs, items, inner_span) = self.parse_mod(exp!(CloseBrace))?; attrs.extend(inner_attrs); - ModKind::Loaded(items, Inline::Yes, inner_span, Ok(())) + ModKind::Loaded(items, Inline::Yes, inner_span) }; Ok(ItemKind::Mod(safety, ident, mod_kind)) } @@ -116,7 +116,8 @@ impl<'a> Parser<'a> { impl<'a> Parser<'a> { pub fn parse_item(&mut self, force_collect: ForceCollect) -> PResult<'a, Option<Box<Item>>> { - let fn_parse_mode = FnParseMode { req_name: |_| true, req_body: true }; + let fn_parse_mode = + FnParseMode { req_name: |_| true, context: FnContext::Free, req_body: true }; self.parse_item_(fn_parse_mode, force_collect).map(|i| i.map(Box::new)) } @@ -975,7 +976,8 @@ impl<'a> Parser<'a> { &mut self, force_collect: ForceCollect, ) -> PResult<'a, Option<Option<Box<AssocItem>>>> { - let fn_parse_mode = FnParseMode { req_name: |_| true, req_body: true }; + let fn_parse_mode = + FnParseMode { req_name: |_| true, context: FnContext::Impl, req_body: true }; self.parse_assoc_item(fn_parse_mode, force_collect) } @@ -983,8 +985,11 @@ impl<'a> Parser<'a> { &mut self, force_collect: ForceCollect, ) -> PResult<'a, Option<Option<Box<AssocItem>>>> { - let fn_parse_mode = - FnParseMode { req_name: |edition| edition >= Edition::Edition2018, req_body: false }; + let fn_parse_mode = FnParseMode { + req_name: |edition| edition >= Edition::Edition2018, + context: FnContext::Trait, + req_body: false, + }; self.parse_assoc_item(fn_parse_mode, force_collect) } @@ -1261,7 +1266,8 @@ impl<'a> Parser<'a> { &mut self, force_collect: ForceCollect, ) -> PResult<'a, Option<Option<Box<ForeignItem>>>> { - let fn_parse_mode = FnParseMode { req_name: |_| true, req_body: false }; + let fn_parse_mode = + FnParseMode { req_name: |_| true, context: FnContext::Free, req_body: false }; Ok(self.parse_item_(fn_parse_mode, force_collect)?.map( |Item { attrs, id, span, vis, kind, tokens }| { let kind = match ForeignItemKind::try_from(kind) { @@ -2135,7 +2141,8 @@ impl<'a> Parser<'a> { let inherited_vis = Visibility { span: DUMMY_SP, kind: VisibilityKind::Inherited, tokens: None }; // We use `parse_fn` to get a span for the function - let fn_parse_mode = FnParseMode { req_name: |_| true, req_body: true }; + let fn_parse_mode = + FnParseMode { req_name: |_| true, context: FnContext::Free, req_body: true }; match self.parse_fn( &mut AttrVec::new(), fn_parse_mode, @@ -2403,6 +2410,9 @@ pub(crate) struct FnParseMode { /// * The span is from Edition 2015. In particular, you can get a /// 2015 span inside a 2021 crate using macros. pub(super) req_name: ReqName, + /// The context in which this function is parsed, used for diagnostics. + /// This indicates the fn is a free function or method and so on. + pub(super) context: FnContext, /// If this flag is set to `true`, then plain, semicolon-terminated function /// prototypes are not allowed here. /// @@ -2424,6 +2434,18 @@ pub(crate) struct FnParseMode { pub(super) req_body: bool, } +/// The context in which a function is parsed. +/// FIXME(estebank, xizheyin): Use more variants. +#[derive(Clone, Copy, PartialEq, Eq)] +pub(crate) enum FnContext { + /// Free context. + Free, + /// A Trait context. + Trait, + /// An Impl block. + Impl, +} + /// Parsing of functions and methods. impl<'a> Parser<'a> { /// Parse a function starting from the front matter (`const ...`) to the body `{ ... }` or `;`. @@ -2439,11 +2461,8 @@ impl<'a> Parser<'a> { let header = self.parse_fn_front_matter(vis, case, FrontMatterParsingMode::Function)?; // `const ... fn` let ident = self.parse_ident()?; // `foo` let mut generics = self.parse_generics()?; // `<'a, T, ...>` - let decl = match self.parse_fn_decl( - fn_parse_mode.req_name, - AllowPlus::Yes, - RecoverReturnSign::Yes, - ) { + let decl = match self.parse_fn_decl(&fn_parse_mode, AllowPlus::Yes, RecoverReturnSign::Yes) + { Ok(decl) => decl, Err(old_err) => { // If we see `for Ty ...` then user probably meant `impl` item. @@ -2961,18 +2980,21 @@ impl<'a> Parser<'a> { /// Parses the parameter list and result type of a function declaration. pub(super) fn parse_fn_decl( &mut self, - req_name: ReqName, + fn_parse_mode: &FnParseMode, ret_allow_plus: AllowPlus, recover_return_sign: RecoverReturnSign, ) -> PResult<'a, Box<FnDecl>> { Ok(Box::new(FnDecl { - inputs: self.parse_fn_params(req_name)?, + inputs: self.parse_fn_params(fn_parse_mode)?, output: self.parse_ret_ty(ret_allow_plus, RecoverQPath::Yes, recover_return_sign)?, })) } /// Parses the parameter list of a function, including the `(` and `)` delimiters. - pub(super) fn parse_fn_params(&mut self, req_name: ReqName) -> PResult<'a, ThinVec<Param>> { + pub(super) fn parse_fn_params( + &mut self, + fn_parse_mode: &FnParseMode, + ) -> PResult<'a, ThinVec<Param>> { let mut first_param = true; // Parse the arguments, starting out with `self` being allowed... if self.token != TokenKind::OpenParen @@ -2988,7 +3010,7 @@ impl<'a> Parser<'a> { let (mut params, _) = self.parse_paren_comma_seq(|p| { p.recover_vcs_conflict_marker(); let snapshot = p.create_snapshot_for_diagnostic(); - let param = p.parse_param_general(req_name, first_param, true).or_else(|e| { + let param = p.parse_param_general(fn_parse_mode, first_param, true).or_else(|e| { let guar = e.emit(); // When parsing a param failed, we should check to make the span of the param // not contain '(' before it. @@ -3019,7 +3041,7 @@ impl<'a> Parser<'a> { /// - `recover_arg_parse` is used to recover from a failed argument parse. pub(super) fn parse_param_general( &mut self, - req_name: ReqName, + fn_parse_mode: &FnParseMode, first_param: bool, recover_arg_parse: bool, ) -> PResult<'a, Param> { @@ -3035,16 +3057,22 @@ impl<'a> Parser<'a> { let is_name_required = match this.token.kind { token::DotDotDot => false, - _ => req_name(this.token.span.with_neighbor(this.prev_token.span).edition()), + _ => (fn_parse_mode.req_name)( + this.token.span.with_neighbor(this.prev_token.span).edition(), + ), }; let (pat, ty) = if is_name_required || this.is_named_param() { debug!("parse_param_general parse_pat (is_name_required:{})", is_name_required); let (pat, colon) = this.parse_fn_param_pat_colon()?; if !colon { let mut err = this.unexpected().unwrap_err(); - return if let Some(ident) = - this.parameter_without_type(&mut err, pat, is_name_required, first_param) - { + return if let Some(ident) = this.parameter_without_type( + &mut err, + pat, + is_name_required, + first_param, + fn_parse_mode, + ) { let guar = err.emit(); Ok((dummy_arg(ident, guar), Trailing::No, UsePreAttrPos::No)) } else { diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs index 0a8a0203013..21f42b54f21 100644 --- a/compiler/rustc_parse/src/parser/mod.rs +++ b/compiler/rustc_parse/src/parser/mod.rs @@ -22,7 +22,7 @@ use std::{fmt, mem, slice}; use attr_wrapper::{AttrWrapper, UsePreAttrPos}; pub use diagnostics::AttemptLocalParseRecovery; pub(crate) use expr::ForbiddenLetReason; -pub(crate) use item::FnParseMode; +pub(crate) use item::{FnContext, FnParseMode}; pub use pat::{CommaRecoveryMode, RecoverColon, RecoverComma}; use path::PathStyle; use rustc_ast::token::{ @@ -1388,15 +1388,26 @@ impl<'a> Parser<'a> { // matching `CloseDelim` we are *after* the delimited sequence, // i.e. at depth `d - 1`. let target_depth = self.token_cursor.stack.len() - 1; - loop { - // Advance one token at a time, so `TokenCursor::next()` - // can capture these tokens if necessary. + + if let Capturing::No = self.capture_state.capturing { + // We are not capturing tokens, so skip to the end of the + // delimited sequence. This is a perf win when dealing with + // declarative macros that pass large `tt` fragments through + // multiple rules, as seen in the uom-0.37.0 crate. + self.token_cursor.curr.bump_to_end(); self.bump(); - if self.token_cursor.stack.len() == target_depth { - debug_assert!(self.token.kind.close_delim().is_some()); - break; + debug_assert_eq!(self.token_cursor.stack.len(), target_depth); + } else { + loop { + // Advance one token at a time, so `TokenCursor::next()` + // can capture these tokens if necessary. + self.bump(); + if self.token_cursor.stack.len() == target_depth { + break; + } } } + debug_assert!(self.token.kind.close_delim().is_some()); // Consume close delimiter self.bump(); diff --git a/compiler/rustc_parse/src/parser/pat.rs b/compiler/rustc_parse/src/parser/pat.rs index a415849b915..9754691a0b9 100644 --- a/compiler/rustc_parse/src/parser/pat.rs +++ b/compiler/rustc_parse/src/parser/pat.rs @@ -24,10 +24,10 @@ use crate::errors::{ GenericArgsInPatRequireTurbofishSyntax, InclusiveRangeExtraEquals, InclusiveRangeMatchArrow, InclusiveRangeNoEnd, InvalidMutInPattern, ParenRangeSuggestion, PatternOnWrongSideOfAt, RemoveLet, RepeatedMutInPattern, SwitchRefBoxOrder, TopLevelOrPatternNotAllowed, - TopLevelOrPatternNotAllowedSugg, TrailingVertNotAllowed, UnexpectedExpressionInPattern, - UnexpectedExpressionInPatternSugg, UnexpectedLifetimeInPattern, UnexpectedParenInRangePat, - UnexpectedParenInRangePatSugg, UnexpectedVertVertBeforeFunctionParam, - UnexpectedVertVertInPattern, WrapInParens, + TopLevelOrPatternNotAllowedSugg, TrailingVertNotAllowed, TrailingVertSuggestion, + UnexpectedExpressionInPattern, UnexpectedExpressionInPatternSugg, UnexpectedLifetimeInPattern, + UnexpectedParenInRangePat, UnexpectedParenInRangePatSugg, + UnexpectedVertVertBeforeFunctionParam, UnexpectedVertVertInPattern, WrapInParens, }; use crate::parser::expr::{DestructuredFloat, could_be_unclosed_char_literal}; use crate::{exp, maybe_recover_from_interpolated_ty_qpath}; @@ -267,10 +267,9 @@ impl<'a> Parser<'a> { if let PatKind::Or(pats) = &pat.kind { let span = pat.span; - let sub = if pats.len() == 1 { - Some(TopLevelOrPatternNotAllowedSugg::RemoveLeadingVert { - span: span.with_hi(span.lo() + BytePos(1)), - }) + let sub = if let [_] = &pats[..] { + let span = span.with_hi(span.lo() + BytePos(1)); + Some(TopLevelOrPatternNotAllowedSugg::RemoveLeadingVert { span }) } else { Some(TopLevelOrPatternNotAllowedSugg::WrapInParens { span, @@ -362,6 +361,9 @@ impl<'a> Parser<'a> { self.dcx().emit_err(TrailingVertNotAllowed { span: self.token.span, start: lo, + suggestion: TrailingVertSuggestion { + span: self.prev_token.span.shrink_to_hi().with_hi(self.token.span.hi()), + }, token: self.token, note_double_vert: self.token.kind == token::OrOr, }); diff --git a/compiler/rustc_parse/src/parser/path.rs b/compiler/rustc_parse/src/parser/path.rs index a6ec3ea4245..37fc723cd89 100644 --- a/compiler/rustc_parse/src/parser/path.rs +++ b/compiler/rustc_parse/src/parser/path.rs @@ -20,7 +20,9 @@ use crate::errors::{ PathFoundAttributeInParams, PathFoundCVariadicParams, PathSingleColon, PathTripleColon, }; use crate::exp; -use crate::parser::{CommaRecoveryMode, ExprKind, RecoverColon, RecoverComma}; +use crate::parser::{ + CommaRecoveryMode, ExprKind, FnContext, FnParseMode, RecoverColon, RecoverComma, +}; /// Specifies how to parse a path. #[derive(Copy, Clone, PartialEq)] @@ -399,7 +401,13 @@ impl<'a> Parser<'a> { let dcx = self.dcx(); let parse_params_result = self.parse_paren_comma_seq(|p| { - let param = p.parse_param_general(|_| false, false, false); + // Inside parenthesized type arguments, we want types only, not names. + let mode = FnParseMode { + context: FnContext::Free, + req_name: |_| false, + req_body: false, + }; + let param = p.parse_param_general(&mode, false, false); param.map(move |param| { if !matches!(param.pat.kind, PatKind::Missing) { dcx.emit_err(FnPathFoundNamedParams { diff --git a/compiler/rustc_parse/src/parser/stmt.rs b/compiler/rustc_parse/src/parser/stmt.rs index 7aacb674253..b4943ff7de6 100644 --- a/compiler/rustc_parse/src/parser/stmt.rs +++ b/compiler/rustc_parse/src/parser/stmt.rs @@ -19,8 +19,8 @@ use super::diagnostics::AttemptLocalParseRecovery; use super::pat::{PatternLocation, RecoverComma}; use super::path::PathStyle; use super::{ - AttrWrapper, BlockMode, FnParseMode, ForceCollect, Parser, Restrictions, SemiColonMode, - Trailing, UsePreAttrPos, + AttrWrapper, BlockMode, FnContext, FnParseMode, ForceCollect, Parser, Restrictions, + SemiColonMode, Trailing, UsePreAttrPos, }; use crate::errors::{self, MalformedLoopLabel}; use crate::exp; @@ -153,7 +153,7 @@ impl<'a> Parser<'a> { attrs.clone(), // FIXME: unwanted clone of attrs false, true, - FnParseMode { req_name: |_| true, req_body: true }, + FnParseMode { req_name: |_| true, context: FnContext::Free, req_body: true }, force_collect, )? { self.mk_stmt(lo.to(item.span), StmtKind::Item(Box::new(item))) diff --git a/compiler/rustc_parse/src/parser/ty.rs b/compiler/rustc_parse/src/parser/ty.rs index 0d479731e73..899a43955ab 100644 --- a/compiler/rustc_parse/src/parser/ty.rs +++ b/compiler/rustc_parse/src/parser/ty.rs @@ -19,6 +19,7 @@ use crate::errors::{ NestedCVariadicType, ReturnTypesUseThinArrow, }; use crate::parser::item::FrontMatterParsingMode; +use crate::parser::{FnContext, FnParseMode}; use crate::{exp, maybe_recover_from_interpolated_ty_qpath}; /// Signals whether parsing a type should allow `+`. @@ -307,11 +308,11 @@ impl<'a> Parser<'a> { // Function pointer type or bound list (trait object type) starting with a poly-trait. // `for<'lt> [unsafe] [extern "ABI"] fn (&'lt S) -> T` // `for<'lt> Trait1<'lt> + Trait2 + 'a` - let (lifetime_defs, _) = self.parse_late_bound_lifetime_defs()?; + let (bound_vars, _) = self.parse_higher_ranked_binder()?; if self.check_fn_front_matter(false, Case::Sensitive) { self.parse_ty_fn_ptr( lo, - lifetime_defs, + bound_vars, Some(self.prev_token.span.shrink_to_lo()), recover_return_sign, )? @@ -325,7 +326,7 @@ impl<'a> Parser<'a> { let path = self.parse_path(PathStyle::Type)?; let parse_plus = allow_plus == AllowPlus::Yes && self.check_plus(); let kind = self.parse_remaining_bounds_path( - lifetime_defs, + bound_vars, path, lo, parse_plus, @@ -358,7 +359,7 @@ impl<'a> Parser<'a> { let path = self.parse_path(PathStyle::Type)?; let parse_plus = allow_plus == AllowPlus::Yes && self.check_plus(); self.parse_remaining_bounds_path( - lifetime_defs, + bound_vars, path, lo, parse_plus, @@ -442,7 +443,7 @@ impl<'a> Parser<'a> { let ty = ts.into_iter().next().unwrap(); let maybe_bounds = allow_plus == AllowPlus::Yes && self.token.is_like_plus(); match ty.kind { - // `(TY_BOUND_NOPAREN) + BOUND + ...`. + // `"(" BareTraitBound ")" "+" Bound "+" ...`. TyKind::Path(None, path) if maybe_bounds => self.parse_remaining_bounds_path( ThinVec::new(), path, @@ -769,7 +770,12 @@ impl<'a> Parser<'a> { if self.may_recover() && self.token == TokenKind::Lt { self.recover_fn_ptr_with_generics(lo, &mut params, param_insertion_point)?; } - let decl = self.parse_fn_decl(|_| false, AllowPlus::No, recover_return_sign)?; + let mode = crate::parser::item::FnParseMode { + req_name: |_| false, + context: FnContext::Free, + req_body: false, + }; + let decl = self.parse_fn_decl(&mode, AllowPlus::No, recover_return_sign)?; let decl_span = span_start.to(self.prev_token.span); Ok(TyKind::FnPtr(Box::new(FnPtrTy { @@ -847,10 +853,13 @@ impl<'a> Parser<'a> { Ok(TyKind::ImplTrait(ast::DUMMY_NODE_ID, bounds)) } - fn parse_precise_capturing_args( - &mut self, - ) -> PResult<'a, (ThinVec<PreciseCapturingArg>, Span)> { - let lo = self.token.span; + /// Parse a use-bound aka precise capturing list. + /// + /// ```ebnf + /// UseBound = "use" "<" (PreciseCapture ("," PreciseCapture)* ","?)? ">" + /// PreciseCapture = "Self" | Ident | Lifetime + /// ``` + fn parse_use_bound(&mut self, lo: Span, parens: ast::Parens) -> PResult<'a, GenericBound> { self.expect_lt()?; let (args, _, _) = self.parse_seq_to_before_tokens( &[exp!(Gt)], @@ -876,7 +885,13 @@ impl<'a> Parser<'a> { }, )?; self.expect_gt()?; - Ok((args, lo.to(self.prev_token.span))) + + if let ast::Parens::Yes = parens { + self.expect(exp!(CloseParen))?; + self.report_parenthesized_bound(lo, self.prev_token.span, "precise capturing lists"); + } + + Ok(GenericBound::Use(args, lo.to(self.prev_token.span))) } /// Is a `dyn B0 + ... + Bn` type allowed here? @@ -934,9 +949,10 @@ impl<'a> Parser<'a> { self.parse_generic_bounds_common(AllowPlus::Yes) } - /// Parses bounds of a type parameter `BOUND + BOUND + ...`, possibly with trailing `+`. + /// Parse generic bounds. /// - /// See `parse_generic_bound` for the `BOUND` grammar. + /// Only if `allow_plus` this parses a `+`-separated list of bounds (trailing `+` is admitted). + /// Otherwise, this only parses a single bound or none. fn parse_generic_bounds_common(&mut self, allow_plus: AllowPlus) -> PResult<'a, GenericBounds> { let mut bounds = Vec::new(); @@ -982,48 +998,56 @@ impl<'a> Parser<'a> { || self.check_keyword(exp!(Use)) } - /// Parses a bound according to the grammar: + /// Parse a bound. + /// /// ```ebnf - /// BOUND = TY_BOUND | LT_BOUND + /// Bound = LifetimeBound | UseBound | TraitBound /// ``` fn parse_generic_bound(&mut self) -> PResult<'a, GenericBound> { - let lo = self.token.span; let leading_token = self.prev_token; + let lo = self.token.span; + + // We only admit parenthesized *trait* bounds. However, we want to gracefully recover from + // other kinds of parenthesized bounds, so parse the opening parenthesis *here*. + // + // In the future we might want to lift this syntactic restriction and + // introduce "`GenericBound::Paren(Box<GenericBound>)`". let parens = if self.eat(exp!(OpenParen)) { ast::Parens::Yes } else { ast::Parens::No }; - let bound = if self.token.is_lifetime() { - self.parse_generic_lt_bound(lo, parens)? + if self.token.is_lifetime() { + self.parse_lifetime_bound(lo, parens) } else if self.eat_keyword(exp!(Use)) { - // parse precise captures, if any. This is `use<'lt, 'lt, P, P>`; a list of - // lifetimes and ident params (including SelfUpper). These are validated later - // for order, duplication, and whether they actually reference params. - let use_span = self.prev_token.span; - let (args, args_span) = self.parse_precise_capturing_args()?; - GenericBound::Use(args, use_span.to(args_span)) + self.parse_use_bound(lo, parens) } else { - self.parse_generic_ty_bound(lo, parens, &leading_token)? - }; - - Ok(bound) + self.parse_trait_bound(lo, parens, &leading_token) + } } - /// Parses a lifetime ("outlives") bound, e.g. `'a`, according to: + /// Parse a lifetime-bound aka outlives-bound. + /// /// ```ebnf - /// LT_BOUND = LIFETIME + /// LifetimeBound = Lifetime /// ``` - fn parse_generic_lt_bound( - &mut self, - lo: Span, - parens: ast::Parens, - ) -> PResult<'a, GenericBound> { + fn parse_lifetime_bound(&mut self, lo: Span, parens: ast::Parens) -> PResult<'a, GenericBound> { let lt = self.expect_lifetime(); - let bound = GenericBound::Outlives(lt); + if let ast::Parens::Yes = parens { - // FIXME(Centril): Consider not erroring here and accepting `('lt)` instead, - // possibly introducing `GenericBound::Paren(Box<GenericBound>)`? - self.recover_paren_lifetime(lo)?; + self.expect(exp!(CloseParen))?; + self.report_parenthesized_bound(lo, self.prev_token.span, "lifetime bounds"); } - Ok(bound) + + Ok(GenericBound::Outlives(lt)) + } + + fn report_parenthesized_bound(&self, lo: Span, hi: Span, kind: &str) -> ErrorGuaranteed { + let mut diag = + self.dcx().struct_span_err(lo.to(hi), format!("{kind} may not be parenthesized")); + diag.multipart_suggestion( + "remove the parentheses", + vec![(lo, String::new()), (hi, String::new())], + Applicability::MachineApplicable, + ); + diag.emit() } /// Emits an error if any trait bound modifiers were present. @@ -1068,27 +1092,17 @@ impl<'a> Parser<'a> { unreachable!("lifetime bound intercepted in `parse_generic_ty_bound` but no modifiers?") } - /// Recover on `('lifetime)` with `(` already eaten. - fn recover_paren_lifetime(&mut self, lo: Span) -> PResult<'a, ()> { - self.expect(exp!(CloseParen))?; - let span = lo.to(self.prev_token.span); - let sugg = errors::RemoveParens { lo, hi: self.prev_token.span }; - - self.dcx().emit_err(errors::ParenthesizedLifetime { span, sugg }); - Ok(()) - } - /// Parses the modifiers that may precede a trait in a bound, e.g. `?Trait` or `[const] Trait`. /// /// If no modifiers are present, this does not consume any tokens. /// /// ```ebnf - /// CONSTNESS = [["["] "const" ["]"]] - /// ASYNCNESS = ["async"] - /// POLARITY = ["?" | "!"] + /// Constness = ("const" | "[" "const" "]")? + /// Asyncness = "async"? + /// Polarity = ("?" | "!")? /// ``` /// - /// See `parse_generic_ty_bound` for the complete grammar of trait bound modifiers. + /// See `parse_trait_bound` for more context. fn parse_trait_bound_modifiers(&mut self) -> PResult<'a, TraitBoundModifiers> { let modifier_lo = self.token.span; let constness = self.parse_bound_constness()?; @@ -1181,20 +1195,21 @@ impl<'a> Parser<'a> { }) } - /// Parses a type bound according to: + /// Parse a trait bound. + /// /// ```ebnf - /// TY_BOUND = TY_BOUND_NOPAREN | (TY_BOUND_NOPAREN) - /// TY_BOUND_NOPAREN = [for<GENERIC_PARAMS> CONSTNESS ASYNCNESS | POLARITY] SIMPLE_PATH + /// TraitBound = BareTraitBound | "(" BareTraitBound ")" + /// BareTraitBound = + /// (HigherRankedBinder Constness Asyncness | Polarity) + /// TypePath /// ``` - /// - /// For example, this grammar accepts `for<'a: 'b> [const] ?m::Trait<'a>`. - fn parse_generic_ty_bound( + fn parse_trait_bound( &mut self, lo: Span, parens: ast::Parens, leading_token: &Token, ) -> PResult<'a, GenericBound> { - let (mut lifetime_defs, binder_span) = self.parse_late_bound_lifetime_defs()?; + let (mut bound_vars, binder_span) = self.parse_higher_ranked_binder()?; let modifiers_lo = self.token.span; let modifiers = self.parse_trait_bound_modifiers()?; @@ -1217,11 +1232,11 @@ impl<'a> Parser<'a> { // e.g. `T: for<'a> 'a` or `T: [const] 'a`. if self.token.is_lifetime() { let _: ErrorGuaranteed = self.error_lt_bound_with_modifiers(modifiers, binder_span); - return self.parse_generic_lt_bound(lo, parens); + return self.parse_lifetime_bound(lo, parens); } - if let (more_lifetime_defs, Some(binder_span)) = self.parse_late_bound_lifetime_defs()? { - lifetime_defs.extend(more_lifetime_defs); + if let (more_bound_vars, Some(binder_span)) = self.parse_higher_ranked_binder()? { + bound_vars.extend(more_bound_vars); self.dcx().emit_err(errors::BinderBeforeModifiers { binder_span, modifiers_span }); } @@ -1281,7 +1296,7 @@ impl<'a> Parser<'a> { }; if self.may_recover() && self.token == TokenKind::OpenParen { - self.recover_fn_trait_with_lifetime_params(&mut path, &mut lifetime_defs)?; + self.recover_fn_trait_with_lifetime_params(&mut path, &mut bound_vars)?; } if let ast::Parens::Yes = parens { @@ -1304,7 +1319,7 @@ impl<'a> Parser<'a> { } let poly_trait = - PolyTraitRef::new(lifetime_defs, path, modifiers, lo.to(self.prev_token.span), parens); + PolyTraitRef::new(bound_vars, path, modifiers, lo.to(self.prev_token.span), parens); Ok(GenericBound::Trait(poly_trait)) } @@ -1314,7 +1329,8 @@ impl<'a> Parser<'a> { self.bump(); let args_lo = self.token.span; let snapshot = self.create_snapshot_for_diagnostic(); - match self.parse_fn_decl(|_| false, AllowPlus::No, RecoverReturnSign::OnlyFatArrow) { + let mode = FnParseMode { req_name: |_| false, context: FnContext::Free, req_body: false }; + match self.parse_fn_decl(&mode, AllowPlus::No, RecoverReturnSign::OnlyFatArrow) { Ok(decl) => { self.dcx().emit_err(ExpectedFnPathFoundFnKeyword { fn_token_span }); Some(ast::Path { @@ -1342,8 +1358,12 @@ impl<'a> Parser<'a> { } } - /// Optionally parses `for<$generic_params>`. - pub(super) fn parse_late_bound_lifetime_defs( + /// Parse an optional higher-ranked binder. + /// + /// ```ebnf + /// HigherRankedBinder = ("for" "<" GenericParams ">")? + /// ``` + pub(super) fn parse_higher_ranked_binder( &mut self, ) -> PResult<'a, (ThinVec<GenericParam>, Option<Span>)> { if self.eat_keyword(exp!(For)) { @@ -1400,8 +1420,9 @@ impl<'a> Parser<'a> { // Parse `(T, U) -> R`. let inputs_lo = self.token.span; + let mode = FnParseMode { req_name: |_| false, context: FnContext::Free, req_body: false }; let inputs: ThinVec<_> = - self.parse_fn_params(|_| false)?.into_iter().map(|input| input.ty).collect(); + self.parse_fn_params(&mode)?.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)?; let args = ast::ParenthesizedArgs { |