diff options
Diffstat (limited to 'compiler/rustc_parse/src/parser')
| -rw-r--r-- | compiler/rustc_parse/src/parser/attr.rs | 37 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/attr_wrapper.rs | 14 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/diagnostics.rs | 85 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/expr.rs | 435 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/item.rs | 171 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/mod.rs | 142 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/nonterminal.rs | 16 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/pat.rs | 18 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/path.rs | 17 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/stmt.rs | 86 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/ty.rs | 69 |
11 files changed, 655 insertions, 435 deletions
diff --git a/compiler/rustc_parse/src/parser/attr.rs b/compiler/rustc_parse/src/parser/attr.rs index 9e4565694..c7d239b64 100644 --- a/compiler/rustc_parse/src/parser/attr.rs +++ b/compiler/rustc_parse/src/parser/attr.rs @@ -55,7 +55,7 @@ impl<'a> Parser<'a> { let span = self.token.span; let mut err = self.sess.span_diagnostic.struct_span_err_with_code( span, - fluent::parser_inner_doc_comment_not_permitted, + fluent::parse_inner_doc_comment_not_permitted, error_code!(E0753), ); if let Some(replacement_span) = self.annotate_following_item_if_applicable( @@ -200,7 +200,7 @@ impl<'a> Parser<'a> { Some(InnerAttrForbiddenReason::AfterOuterDocComment { prev_doc_comment_span }) => { let mut diag = self.struct_span_err( attr_sp, - fluent::parser_inner_attr_not_permitted_after_outer_doc_comment, + fluent::parse_inner_attr_not_permitted_after_outer_doc_comment, ); diag.span_label(attr_sp, fluent::label_attr) .span_label(prev_doc_comment_span, fluent::label_prev_doc_comment); @@ -209,18 +209,18 @@ impl<'a> Parser<'a> { Some(InnerAttrForbiddenReason::AfterOuterAttribute { prev_outer_attr_sp }) => { let mut diag = self.struct_span_err( attr_sp, - fluent::parser_inner_attr_not_permitted_after_outer_attr, + fluent::parse_inner_attr_not_permitted_after_outer_attr, ); diag.span_label(attr_sp, fluent::label_attr) .span_label(prev_outer_attr_sp, fluent::label_prev_attr); diag } Some(InnerAttrForbiddenReason::InCodeBlock) | None => { - self.struct_span_err(attr_sp, fluent::parser_inner_attr_not_permitted) + self.struct_span_err(attr_sp, fluent::parse_inner_attr_not_permitted) } }; - diag.note(fluent::parser_inner_attr_explanation); + diag.note(fluent::parse_inner_attr_explanation); if self .annotate_following_item_if_applicable( &mut diag, @@ -229,7 +229,7 @@ impl<'a> Parser<'a> { ) .is_some() { - diag.note(fluent::parser_outer_attr_explanation); + diag.note(fluent::parse_outer_attr_explanation); }; diag.emit(); } @@ -245,9 +245,9 @@ impl<'a> Parser<'a> { /// PATH `=` UNSUFFIXED_LIT /// The delimiters or `=` are still put into the resulting token stream. pub fn parse_attr_item(&mut self, capture_tokens: bool) -> PResult<'a, ast::AttrItem> { - let item = match self.token.kind { - token::Interpolated(ref nt) => match **nt { - Nonterminal::NtMeta(ref item) => Some(item.clone().into_inner()), + let item = match &self.token.kind { + token::Interpolated(nt) => match &**nt { + Nonterminal::NtMeta(item) => Some(item.clone().into_inner()), _ => None, }, _ => None, @@ -315,9 +315,10 @@ impl<'a> Parser<'a> { Ok(attrs) } - pub(crate) fn parse_unsuffixed_lit(&mut self) -> PResult<'a, ast::Lit> { - let lit = self.parse_lit()?; - debug!("checking if {:?} is unusuffixed", lit); + // Note: must be unsuffixed. + pub(crate) fn parse_unsuffixed_meta_item_lit(&mut self) -> PResult<'a, ast::MetaItemLit> { + let lit = self.parse_meta_item_lit()?; + debug!("checking if {:?} is unsuffixed", lit); if !lit.kind.is_unsuffixed() { self.sess.emit_err(SuffixedLiteralInAttribute { span: lit.span }); @@ -364,9 +365,9 @@ impl<'a> Parser<'a> { /// meta_item_inner : (meta_item | UNSUFFIXED_LIT) (',' meta_item_inner)? ; /// ``` pub fn parse_meta_item(&mut self) -> PResult<'a, ast::MetaItem> { - let nt_meta = match self.token.kind { - token::Interpolated(ref nt) => match **nt { - token::NtMeta(ref e) => Some(e.clone()), + let nt_meta = match &self.token.kind { + token::Interpolated(nt) => match &**nt { + token::NtMeta(e) => Some(e.clone()), _ => None, }, _ => None, @@ -391,7 +392,7 @@ impl<'a> Parser<'a> { pub(crate) fn parse_meta_item_kind(&mut self) -> PResult<'a, ast::MetaItemKind> { Ok(if self.eat(&token::Eq) { - ast::MetaItemKind::NameValue(self.parse_unsuffixed_lit()?) + ast::MetaItemKind::NameValue(self.parse_unsuffixed_meta_item_lit()?) } else if self.check(&token::OpenDelim(Delimiter::Parenthesis)) { // Matches `meta_seq = ( COMMASEP(meta_item_inner) )`. let (list, _) = self.parse_paren_comma_seq(|p| p.parse_meta_item_inner())?; @@ -403,8 +404,8 @@ impl<'a> Parser<'a> { /// Matches `meta_item_inner : (meta_item | UNSUFFIXED_LIT) ;`. fn parse_meta_item_inner(&mut self) -> PResult<'a, ast::NestedMetaItem> { - match self.parse_unsuffixed_lit() { - Ok(lit) => return Ok(ast::NestedMetaItem::Literal(lit)), + match self.parse_unsuffixed_meta_item_lit() { + Ok(lit) => return Ok(ast::NestedMetaItem::Lit(lit)), Err(err) => err.cancel(), } diff --git a/compiler/rustc_parse/src/parser/attr_wrapper.rs b/compiler/rustc_parse/src/parser/attr_wrapper.rs index 1b16ecb5e..a084a7010 100644 --- a/compiler/rustc_parse/src/parser/attr_wrapper.rs +++ b/compiler/rustc_parse/src/parser/attr_wrapper.rs @@ -5,7 +5,8 @@ use rustc_ast::tokenstream::{AttrTokenTree, DelimSpan, LazyAttrTokenStream, Spac use rustc_ast::{self as ast}; use rustc_ast::{AttrVec, Attribute, HasAttrs, HasTokens}; use rustc_errors::PResult; -use rustc_span::{sym, Span}; +use rustc_session::parse::ParseSess; +use rustc_span::{sym, Span, DUMMY_SP}; use std::convert::TryInto; use std::ops::Range; @@ -39,12 +40,17 @@ impl AttrWrapper { pub fn empty() -> AttrWrapper { AttrWrapper { attrs: AttrVec::new(), start_pos: usize::MAX } } - // FIXME: Delay span bug here? - pub(crate) fn take_for_recovery(self) -> AttrVec { + + pub(crate) fn take_for_recovery(self, sess: &ParseSess) -> AttrVec { + sess.span_diagnostic.delay_span_bug( + self.attrs.get(0).map(|attr| attr.span).unwrap_or(DUMMY_SP), + "AttrVec is taken for recovery but no error is produced", + ); + self.attrs } - // Prepend `self.attrs` to `attrs`. + /// Prepend `self.attrs` to `attrs`. // FIXME: require passing an NT to prevent misuse of this method pub(crate) fn prepend_to_nt_inner(self, attrs: &mut AttrVec) { let mut self_attrs = self.attrs; diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs index 309717350..c316a4dd6 100644 --- a/compiler/rustc_parse/src/parser/diagnostics.rs +++ b/compiler/rustc_parse/src/parser/diagnostics.rs @@ -18,6 +18,7 @@ use crate::errors::{ }; use crate::lexer::UnmatchedBrace; +use crate::parser; use rustc_ast as ast; use rustc_ast::ptr::P; use rustc_ast::token::{self, Delimiter, Lit, LitKind, TokenKind}; @@ -37,11 +38,10 @@ use rustc_session::errors::ExprParenthesesNeeded; use rustc_span::source_map::Spanned; use rustc_span::symbol::{kw, sym, Ident}; use rustc_span::{Span, SpanSnippetError, DUMMY_SP}; -use std::ops::{Deref, DerefMut}; - use std::mem::take; - -use crate::parser; +use std::ops::{Deref, DerefMut}; +use thin_vec::{thin_vec, ThinVec}; +use tracing::{debug, trace}; /// Creates a placeholder argument. pub(super) fn dummy_arg(ident: Ident) -> Param { @@ -65,7 +65,7 @@ pub(super) fn dummy_arg(ident: Ident) -> Param { pub(super) trait RecoverQPath: Sized + 'static { const PATH_STYLE: PathStyle = PathStyle::Expr; fn to_ty(&self) -> Option<P<Ty>>; - fn recovered(qself: Option<QSelf>, path: ast::Path) -> Self; + fn recovered(qself: Option<P<QSelf>>, path: ast::Path) -> Self; } impl RecoverQPath for Ty { @@ -73,7 +73,7 @@ impl RecoverQPath for Ty { fn to_ty(&self) -> Option<P<Ty>> { Some(P(self.clone())) } - fn recovered(qself: Option<QSelf>, path: ast::Path) -> Self { + fn recovered(qself: Option<P<QSelf>>, path: ast::Path) -> Self { Self { span: path.span, kind: TyKind::Path(qself, path), @@ -87,7 +87,7 @@ impl RecoverQPath for Pat { fn to_ty(&self) -> Option<P<Ty>> { self.to_ty() } - fn recovered(qself: Option<QSelf>, path: ast::Path) -> Self { + fn recovered(qself: Option<P<QSelf>>, path: ast::Path) -> Self { Self { span: path.span, kind: PatKind::Path(qself, path), @@ -101,7 +101,7 @@ impl RecoverQPath for Expr { fn to_ty(&self) -> Option<P<Ty>> { self.to_ty() } - fn recovered(qself: Option<QSelf>, path: ast::Path) -> Self { + fn recovered(qself: Option<P<QSelf>>, path: ast::Path) -> Self { Self { span: path.span, kind: ExprKind::Path(qself, path), @@ -224,9 +224,9 @@ impl MultiSugg { } } -// SnapshotParser is used to create a snapshot of the parser -// without causing duplicate errors being emitted when the `Parser` -// is dropped. +/// SnapshotParser is used to create a snapshot of the parser +/// without causing duplicate errors being emitted when the `Parser` +/// is dropped. pub struct SnapshotParser<'a> { parser: Parser<'a>, unclosed_delims: Vec<UnmatchedBrace>, @@ -638,8 +638,11 @@ impl<'a> Parser<'a> { // field: value, // } let mut snapshot = self.create_snapshot_for_diagnostic(); - let path = - Path { segments: vec![], span: self.prev_token.span.shrink_to_lo(), tokens: None }; + let path = Path { + segments: ThinVec::new(), + span: self.prev_token.span.shrink_to_lo(), + tokens: None, + }; let struct_expr = snapshot.parse_struct_expr(None, path, false); let block_tail = self.parse_block_tail(lo, s, AttemptLocalParseRecovery::No); return Some(match (struct_expr, block_tail) { @@ -769,6 +772,10 @@ impl<'a> Parser<'a> { segment: &PathSegment, end: &[&TokenKind], ) -> bool { + if !self.may_recover() { + return false; + } + // This function is intended to be invoked after parsing a path segment where there are two // cases: // @@ -863,6 +870,10 @@ impl<'a> Parser<'a> { /// Check if a method call with an intended turbofish has been written without surrounding /// angle brackets. pub(super) fn check_turbofish_missing_angle_brackets(&mut self, segment: &mut PathSegment) { + if !self.may_recover() { + return; + } + if token::ModSep == self.token.kind && segment.args.is_none() { let snapshot = self.create_snapshot_for_diagnostic(); self.bump(); @@ -926,7 +937,7 @@ impl<'a> Parser<'a> { if self.eat(&token::Gt) { e.span_suggestion_verbose( binop.span.shrink_to_lo(), - fluent::parser_sugg_turbofish_syntax, + fluent::parse_sugg_turbofish_syntax, "::", Applicability::MaybeIncorrect, ) @@ -962,7 +973,7 @@ impl<'a> Parser<'a> { inner_op: &Expr, outer_op: &Spanned<AssocOp>, ) -> bool /* advanced the cursor */ { - if let ExprKind::Binary(op, ref l1, ref r1) = inner_op.kind { + if let ExprKind::Binary(op, l1, r1) = &inner_op.kind { if let ExprKind::Field(_, ident) = l1.kind && ident.as_str().parse::<i32>().is_err() && !matches!(r1.kind, ExprKind::Lit(_)) @@ -1068,8 +1079,8 @@ impl<'a> Parser<'a> { let mk_err_expr = |this: &Self, span| Ok(Some(this.mk_expr(span, ExprKind::Err))); - match inner_op.kind { - ExprKind::Binary(op, ref l1, ref r1) if op.node.is_comparison() => { + match &inner_op.kind { + ExprKind::Binary(op, l1, r1) if op.node.is_comparison() => { let mut err = ComparisonOperatorsCannotBeChained { span: vec![op.span, self.prev_token.span], suggest_turbofish: None, @@ -1226,8 +1237,8 @@ impl<'a> Parser<'a> { let bounds = self.parse_generic_bounds(None)?; let sum_span = ty.span.to(self.prev_token.span); - let sub = match ty.kind { - TyKind::Rptr(ref lifetime, ref mut_ty) => { + let sub = match &ty.kind { + TyKind::Rptr(lifetime, mut_ty) => { let sum_with_parens = pprust::to_string(|s| { s.s.word("&"); s.print_opt_lifetime(lifetime); @@ -1396,6 +1407,10 @@ impl<'a> Parser<'a> { &mut self, base: P<T>, ) -> PResult<'a, P<T>> { + if !self.may_recover() { + return Ok(base); + } + // Do not add `::` to expected tokens. if self.token == token::ModSep { if let Some(ty) = base.to_ty() { @@ -1414,7 +1429,7 @@ impl<'a> Parser<'a> { ) -> PResult<'a, P<T>> { self.expect(&token::ModSep)?; - let mut path = ast::Path { segments: Vec::new(), span: DUMMY_SP, tokens: None }; + let mut path = ast::Path { segments: ThinVec::new(), span: DUMMY_SP, tokens: None }; self.parse_path_segments(&mut path.segments, T::PATH_STYLE, None)?; path.span = ty_span.to(self.prev_token.span); @@ -1425,7 +1440,7 @@ impl<'a> Parser<'a> { }); let path_span = ty_span.shrink_to_hi(); // Use an empty path since `position == 0`. - Ok(P(T::recovered(Some(QSelf { ty, path_span, position: 0 }), path))) + Ok(P(T::recovered(Some(P(QSelf { ty, path_span, position: 0 })), path))) } pub fn maybe_consume_incorrect_semicolon(&mut self, items: &[P<Item>]) -> bool { @@ -1641,15 +1656,29 @@ impl<'a> Parser<'a> { (token::CloseDelim(Delimiter::Parenthesis), Some(begin_par_sp)) => { self.bump(); + let sm = self.sess.source_map(); + let left = begin_par_sp; + let right = self.prev_token.span; + let left_snippet = if let Ok(snip) = sm.span_to_prev_source(left) && + !snip.ends_with(' ') { + " ".to_string() + } else { + "".to_string() + }; + + let right_snippet = if let Ok(snip) = sm.span_to_next_source(right) && + !snip.starts_with(' ') { + " ".to_string() + } else { + "".to_string() + }; + self.sess.emit_err(ParenthesesInForHead { - span: vec![begin_par_sp, self.prev_token.span], + span: vec![left, right], // With e.g. `for (x) in y)` this would replace `(x) in y)` // with `x) in y)` which is syntactically invalid. // However, this is prevented before we get here. - sugg: ParenthesesInForHeadSugg { - left: begin_par_sp, - right: self.prev_token.span, - }, + sugg: ParenthesesInForHeadSugg { left, right, left_snippet, right_snippet }, }); // Unwrap `(pat)` into `pat` to avoid the `unused_parens` lint. @@ -2408,7 +2437,7 @@ impl<'a> Parser<'a> { None, Path { span: new_span, - segments: vec![ + segments: thin_vec![ PathSegment::from_ident(*old_ident), PathSegment::from_ident(*ident), ], @@ -2536,7 +2565,7 @@ impl<'a> Parser<'a> { if let [a, b] = segments { let (a_span, b_span) = (a.span(), b.span()); let between_span = a_span.shrink_to_hi().to(b_span.shrink_to_lo()); - if self.span_to_snippet(between_span).as_ref().map(|a| &a[..]) == Ok(":: ") { + if self.span_to_snippet(between_span).as_deref() == Ok(":: ") { return Err(DoubleColonInBound { span: path.span.shrink_to_hi(), between: between_span, diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index a781748ef..f6a6ed379 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -7,46 +7,42 @@ use super::{ }; use crate::errors::{ ArrayBracketsInsteadOfSpaces, ArrayBracketsInsteadOfSpacesSugg, AsyncMoveOrderIncorrect, - BinaryFloatLiteralNotSupported, BracesForStructLiteral, CatchAfterTry, CommaAfterBaseStruct, - ComparisonInterpretedAsGeneric, ComparisonOrShiftInterpretedAsGenericSugg, - DoCatchSyntaxRemoved, DotDotDot, EqFieldInit, ExpectedElseBlock, ExpectedExpressionFoundLet, + BracesForStructLiteral, CatchAfterTry, CommaAfterBaseStruct, ComparisonInterpretedAsGeneric, + ComparisonOrShiftInterpretedAsGenericSugg, DoCatchSyntaxRemoved, DotDotDot, EqFieldInit, + ExpectedElseBlock, ExpectedEqForLetExpr, ExpectedExpressionFoundLet, FieldExpressionWithGeneric, FloatLiteralRequiresIntegerPart, FoundExprWouldBeStmt, - HexadecimalFloatLiteralNotSupported, IfExpressionMissingCondition, - IfExpressionMissingThenBlock, IfExpressionMissingThenBlockSub, IntLiteralTooLarge, + IfExpressionMissingCondition, IfExpressionMissingThenBlock, IfExpressionMissingThenBlockSub, InvalidBlockMacroSegment, InvalidComparisonOperator, InvalidComparisonOperatorSub, - InvalidFloatLiteralSuffix, InvalidFloatLiteralWidth, InvalidIntLiteralWidth, - InvalidInterpolatedExpression, InvalidLiteralSuffix, InvalidLiteralSuffixOnTupleIndex, - InvalidLogicalOperator, InvalidLogicalOperatorSub, InvalidNumLiteralBasePrefix, - InvalidNumLiteralSuffix, LabeledLoopInBreak, LeadingPlusNotSupported, LeftArrowOperator, + InvalidInterpolatedExpression, InvalidLiteralSuffixOnTupleIndex, InvalidLogicalOperator, + InvalidLogicalOperatorSub, LabeledLoopInBreak, LeadingPlusNotSupported, LeftArrowOperator, LifetimeInBorrowExpression, MacroInvocationWithQualifiedPath, MalformedLoopLabel, MatchArmBodyWithoutBraces, MatchArmBodyWithoutBracesSugg, MissingCommaAfterMatchArm, - MissingInInForLoop, MissingInInForLoopSub, MissingSemicolonBeforeArray, NoFieldsForFnCall, - NotAsNegationOperator, NotAsNegationOperatorSub, OctalFloatLiteralNotSupported, + MissingDotDot, MissingInInForLoop, MissingInInForLoopSub, MissingSemicolonBeforeArray, + NoFieldsForFnCall, NotAsNegationOperator, NotAsNegationOperatorSub, OuterAttributeNotAllowedOnIfElse, ParenthesesWithStructFields, RequireColonAfterLabeledExpression, ShiftInterpretedAsGeneric, StructLiteralNotAllowedHere, - StructLiteralNotAllowedHereSugg, TildeAsUnaryOperator, UnexpectedTokenAfterLabel, - UnexpectedTokenAfterLabelSugg, WrapExpressionInParentheses, + StructLiteralNotAllowedHereSugg, TildeAsUnaryOperator, UnexpectedIfWithIf, + UnexpectedTokenAfterLabel, UnexpectedTokenAfterLabelSugg, WrapExpressionInParentheses, }; use crate::maybe_recover_from_interpolated_ty_qpath; - use core::mem; use rustc_ast::ptr::P; use rustc_ast::token::{self, Delimiter, Token, TokenKind}; use rustc_ast::tokenstream::Spacing; +use rustc_ast::util::case::Case; use rustc_ast::util::classify; -use rustc_ast::util::literal::LitError; use rustc_ast::util::parser::{prec_let_scrutinee_needs_par, AssocOp, Fixity}; use rustc_ast::visit::Visitor; -use rustc_ast::{self as ast, AttrStyle, AttrVec, CaptureBy, ExprField, Lit, UnOp, DUMMY_NODE_ID}; +use rustc_ast::{self as ast, AttrStyle, AttrVec, CaptureBy, ExprField, UnOp, DUMMY_NODE_ID}; use rustc_ast::{AnonConst, BinOp, BinOpKind, FnDecl, FnRetTy, MacCall, Param, Ty, TyKind}; use rustc_ast::{Arm, Async, BlockCheckMode, Expr, ExprKind, Label, Movability, RangeLimits}; -use rustc_ast::{ClosureBinder, StmtKind}; +use rustc_ast::{ClosureBinder, MetaItemLit, StmtKind}; use rustc_ast_pretty::pprust; use rustc_errors::{ Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed, IntoDiagnostic, PResult, StashKey, }; -use rustc_session::errors::ExprParenthesesNeeded; +use rustc_session::errors::{report_lit_error, ExprParenthesesNeeded}; use rustc_session::lint::builtin::BREAK_WITH_LABEL_AND_LOOP; use rustc_session::lint::BuiltinLintDiagnostics; use rustc_span::source_map::{self, Span, Spanned}; @@ -132,7 +128,7 @@ impl<'a> Parser<'a> { Ok(expr) => Ok(expr), Err(mut err) => match self.token.ident() { Some((Ident { name: kw::Underscore, .. }, false)) - if self.look_ahead(1, |t| t == &token::Comma) => + if self.may_recover() && self.look_ahead(1, |t| t == &token::Comma) => { // Special-case handling of `foo(_, _, _)` err.emit(); @@ -394,20 +390,11 @@ impl<'a> Parser<'a> { // want to keep their span info to improve diagnostics in these cases in a later stage. (true, Some(AssocOp::Multiply)) | // `{ 42 } *foo = bar;` or `{ 42 } * 3` (true, Some(AssocOp::Subtract)) | // `{ 42 } -5` - (true, Some(AssocOp::Add)) // `{ 42 } + 42 - // If the next token is a keyword, then the tokens above *are* unambiguously incorrect: - // `if x { a } else { b } && if y { c } else { d }` - if !self.look_ahead(1, |t| t.is_used_keyword()) => { - // These cases are ambiguous and can't be identified in the parser alone. - let sp = self.sess.source_map().start_point(self.token.span); - self.sess.ambiguous_block_expr_parse.borrow_mut().insert(sp, lhs.span); - false - } - (true, Some(AssocOp::LAnd)) | - (true, Some(AssocOp::LOr)) | - (true, Some(AssocOp::BitOr)) => { - // `{ 42 } &&x` (#61475) or `{ 42 } && if x { 1 } else { 0 }`. Separated from the - // above due to #74233. + (true, Some(AssocOp::Add)) | // `{ 42 } + 42` (unary plus) + (true, Some(AssocOp::LAnd)) | // `{ 42 } &&x` (#61475) or `{ 42 } && if x { 1 } else { 0 }` + (true, Some(AssocOp::LOr)) | // `{ 42 } || 42` ("logical or" or closure) + (true, Some(AssocOp::BitOr)) // `{ 42 } | 42` or `{ 42 } |x| 42` + => { // These cases are ambiguous and can't be identified in the parser alone. // // Bitwise AND is left out because guessing intent is hard. We can make @@ -418,7 +405,7 @@ impl<'a> Parser<'a> { self.sess.ambiguous_block_expr_parse.borrow_mut().insert(sp, lhs.span); false } - (true, Some(ref op)) if !op.can_continue_expr_unambiguously() => false, + (true, Some(op)) if !op.can_continue_expr_unambiguously() => false, (true, Some(_)) => { self.error_found_expr_would_be_stmt(lhs); true @@ -456,7 +443,7 @@ impl<'a> Parser<'a> { return None; } (Some(op), _) => (op, self.token.span), - (None, Some((Ident { name: sym::and, span }, false))) => { + (None, Some((Ident { name: sym::and, span }, false))) if self.may_recover() => { self.sess.emit_err(InvalidLogicalOperator { span: self.token.span, incorrect: "and".into(), @@ -464,7 +451,7 @@ impl<'a> Parser<'a> { }); (AssocOp::LAnd, span) } - (None, Some((Ident { name: sym::or, span }, false))) => { + (None, Some((Ident { name: sym::or, span }, false))) if self.may_recover() => { self.sess.emit_err(InvalidLogicalOperator { span: self.token.span, incorrect: "or".into(), @@ -615,7 +602,7 @@ impl<'a> Parser<'a> { token::Ident(..) if this.token.is_keyword(kw::Box) => { make_it!(this, attrs, |this, _| this.parse_box_expr(lo)) } - token::Ident(..) if this.is_mistaken_not_ident_negation() => { + token::Ident(..) if this.may_recover() && this.is_mistaken_not_ident_negation() => { make_it!(this, attrs, |this, _| this.recover_not_expr(lo)) } _ => return this.parse_dot_or_call_expr(Some(attrs)), @@ -718,6 +705,10 @@ impl<'a> Parser<'a> { let cast_expr = match self.parse_as_cast_ty() { Ok(rhs) => mk_expr(self, lhs, rhs), Err(type_err) => { + if !self.may_recover() { + return Err(type_err); + } + // Rewind to before attempting to parse the type with generics, to recover // from situations like `x as usize < y` in which we first tried to parse // `usize < y` as a type with generic arguments. @@ -829,23 +820,18 @@ impl<'a> Parser<'a> { ("cast", None) }; - // Save the memory location of expr before parsing any following postfix operators. - // This will be compared with the memory location of the output expression. - // If they different we can assume we parsed another expression because the existing expression is not reallocated. - let addr_before = &*cast_expr as *const _ as usize; let with_postfix = self.parse_dot_or_call_expr_with_(cast_expr, span)?; - let changed = addr_before != &*with_postfix as *const _ as usize; // Check if an illegal postfix operator has been added after the cast. - // If the resulting expression is not a cast, or has a different memory location, it is an illegal postfix operator. - if !matches!(with_postfix.kind, ExprKind::Cast(_, _) | ExprKind::Type(_, _)) || changed { + // If the resulting expression is not a cast, it is an illegal postfix operator. + if !matches!(with_postfix.kind, ExprKind::Cast(_, _) | ExprKind::Type(_, _)) { let msg = format!( "{cast_kind} cannot be followed by {}", match with_postfix.kind { ExprKind::Index(_, _) => "indexing", ExprKind::Try(_) => "`?`", ExprKind::Field(_, _) => "a field access", - ExprKind::MethodCall(_, _, _, _) => "a method call", + ExprKind::MethodCall(_) => "a method call", ExprKind::Call(_, _) => "a function call", ExprKind::Await(_) => "`.await`", ExprKind::Err => return Ok(with_postfix), @@ -1197,6 +1183,10 @@ impl<'a> Parser<'a> { seq: &mut PResult<'a, P<Expr>>, snapshot: Option<(SnapshotParser<'a>, ExprKind)>, ) -> Option<P<Expr>> { + if !self.may_recover() { + return None; + } + match (seq.as_mut(), snapshot) { (Err(err), Some((mut snapshot, ExprKind::Path(None, path)))) => { snapshot.bump(); // `(` @@ -1263,24 +1253,32 @@ impl<'a> Parser<'a> { } let fn_span_lo = self.token.span; - let mut segment = self.parse_path_segment(PathStyle::Expr, None)?; - self.check_trailing_angle_brackets(&segment, &[&token::OpenDelim(Delimiter::Parenthesis)]); - self.check_turbofish_missing_angle_brackets(&mut segment); + let mut seg = self.parse_path_segment(PathStyle::Expr, None)?; + self.check_trailing_angle_brackets(&seg, &[&token::OpenDelim(Delimiter::Parenthesis)]); + self.check_turbofish_missing_angle_brackets(&mut seg); if self.check(&token::OpenDelim(Delimiter::Parenthesis)) { // Method call `expr.f()` let args = self.parse_paren_expr_seq()?; let fn_span = fn_span_lo.to(self.prev_token.span); let span = lo.to(self.prev_token.span); - Ok(self.mk_expr(span, ExprKind::MethodCall(segment, self_arg, args, fn_span))) + Ok(self.mk_expr( + span, + ExprKind::MethodCall(Box::new(ast::MethodCall { + seg, + receiver: self_arg, + args, + span: fn_span, + })), + )) } else { // Field access `expr.f` - if let Some(args) = segment.args { + if let Some(args) = seg.args { self.sess.emit_err(FieldExpressionWithGeneric(args.span())); } let span = lo.to(self.prev_token.span); - Ok(self.mk_expr(span, ExprKind::Field(self_arg, segment.ident))) + Ok(self.mk_expr(span, ExprKind::Field(self_arg, seg.ident))) } } @@ -1360,7 +1358,7 @@ impl<'a> Parser<'a> { ) } else if self.check_inline_const(0) { self.parse_const_block(lo.to(self.token.span), false) - } else if self.is_do_catch_block() { + } else if self.may_recover() && self.is_do_catch_block() { self.recover_do_catch() } else if self.is_try_block() { self.expect_keyword(kw::Try)?; @@ -1411,9 +1409,9 @@ impl<'a> Parser<'a> { fn parse_lit_expr(&mut self) -> PResult<'a, P<Expr>> { let lo = self.token.span; - match self.parse_opt_lit() { - Some(literal) => { - let expr = self.mk_expr(lo.to(self.prev_token.span), ExprKind::Lit(literal)); + match self.parse_opt_token_lit() { + Some((token_lit, _)) => { + let expr = self.mk_expr(lo.to(self.prev_token.span), ExprKind::Lit(token_lit)); self.maybe_recover_from_bad_qpath(expr) } None => self.try_macro_suggestion(), @@ -1494,12 +1492,12 @@ impl<'a> Parser<'a> { let lo = path.span; let mac = P(MacCall { path, - args: self.parse_mac_args()?, + args: self.parse_delim_args()?, prior_type_ascription: self.last_type_ascription, }); (lo.to(self.prev_token.span), ExprKind::MacCall(mac)) } else if self.check(&token::OpenDelim(Delimiter::Brace)) && - let Some(expr) = self.maybe_parse_struct_expr(qself.as_ref(), &path) { + let Some(expr) = self.maybe_parse_struct_expr(&qself, &path) { if qself.is_some() { self.sess.gated_spans.gate(sym::more_qualified_paths, path.span); } @@ -1532,6 +1530,7 @@ impl<'a> Parser<'a> { { self.parse_block_expr(label, lo, BlockCheckMode::Default) } else if !ate_colon + && self.may_recover() && (matches!(self.token.kind, token::CloseDelim(_) | token::Comma) || self.token.is_op()) { @@ -1543,7 +1542,7 @@ impl<'a> Parser<'a> { }) }); consume_colon = false; - Ok(self.mk_expr(lo, ExprKind::Lit(lit))) + Ok(self.mk_expr(lo, ExprKind::Lit(lit.token_lit))) } else if !ate_colon && (self.check_noexpect(&TokenKind::Comma) || self.check_noexpect(&TokenKind::Gt)) { @@ -1620,10 +1619,10 @@ impl<'a> Parser<'a> { /// Emit an error when a char is parsed as a lifetime because of a missing quote pub(super) fn recover_unclosed_char( - &mut self, + &self, lifetime: Ident, - err: impl FnOnce(&mut Self) -> DiagnosticBuilder<'a, ErrorGuaranteed>, - ) -> ast::Lit { + err: impl FnOnce(&Self) -> DiagnosticBuilder<'a, ErrorGuaranteed>, + ) -> ast::MetaItemLit { if let Some(mut diag) = self.sess.span_diagnostic.steal_diagnostic(lifetime.span, StashKey::LifetimeIsChar) { @@ -1644,9 +1643,10 @@ impl<'a> Parser<'a> { ) .emit(); } - ast::Lit { - token_lit: token::Lit::new(token::LitKind::Char, lifetime.name, None), - kind: ast::LitKind::Char(lifetime.name.as_str().chars().next().unwrap_or('_')), + let name = lifetime.without_first_quote().name; + ast::MetaItemLit { + token_lit: token::Lit::new(token::LitKind::Char, name, None), + kind: ast::LitKind::Char(name.as_str().chars().next().unwrap_or('_')), span: lifetime.span, } } @@ -1719,13 +1719,13 @@ impl<'a> Parser<'a> { || !self.restrictions.contains(Restrictions::NO_STRUCT_LITERAL) { let expr = self.parse_expr_opt()?; - if let Some(ref expr) = expr { + if let Some(expr) = &expr { if label.is_some() && matches!( expr.kind, ExprKind::While(_, _, None) | ExprKind::ForLoop(_, _, _, None) - | ExprKind::Loop(_, None) + | ExprKind::Loop(_, None, _) | ExprKind::Block(_, None) ) { @@ -1759,8 +1759,8 @@ impl<'a> Parser<'a> { /// Returns a string literal if the next token is a string literal. /// In case of error returns `Some(lit)` if the next token is a literal with a wrong kind, /// and returns `None` if the next token is not literal at all. - pub fn parse_str_lit(&mut self) -> Result<ast::StrLit, Option<Lit>> { - match self.parse_opt_lit() { + pub fn parse_str_lit(&mut self) -> Result<ast::StrLit, Option<MetaItemLit>> { + match self.parse_opt_meta_item_lit() { Some(lit) => match lit.kind { ast::LitKind::Str(symbol_unescaped, style) => Ok(ast::StrLit { style, @@ -1775,41 +1775,47 @@ impl<'a> Parser<'a> { } } - pub(super) fn parse_lit(&mut self) -> PResult<'a, Lit> { - self.parse_opt_lit().ok_or(()).or_else(|()| { - if let token::Interpolated(inner) = &self.token.kind { - let expr = match inner.as_ref() { - token::NtExpr(expr) => Some(expr), - token::NtLiteral(expr) => Some(expr), - _ => None, - }; - if let Some(expr) = expr { - if matches!(expr.kind, ExprKind::Err) { - let mut err = InvalidInterpolatedExpression { span: self.token.span } - .into_diagnostic(&self.sess.span_diagnostic); - err.downgrade_to_delayed_bug(); - return Err(err); - } - } - } - let token = self.token.clone(); - let err = |self_: &mut Self| { - let msg = format!("unexpected token: {}", super::token_descr(&token)); - self_.struct_span_err(token.span, &msg) + fn handle_missing_lit(&mut self) -> PResult<'a, MetaItemLit> { + if let token::Interpolated(inner) = &self.token.kind { + let expr = match inner.as_ref() { + token::NtExpr(expr) => Some(expr), + token::NtLiteral(expr) => Some(expr), + _ => None, }; - // On an error path, eagerly consider a lifetime to be an unclosed character lit - if self.token.is_lifetime() { - let lt = self.expect_lifetime(); - Ok(self.recover_unclosed_char(lt.ident, err)) - } else { - Err(err(self)) + if let Some(expr) = expr { + if matches!(expr.kind, ExprKind::Err) { + let mut err = InvalidInterpolatedExpression { span: self.token.span } + .into_diagnostic(&self.sess.span_diagnostic); + err.downgrade_to_delayed_bug(); + return Err(err); + } } - }) + } + let token = self.token.clone(); + let err = |self_: &Self| { + let msg = format!("unexpected token: {}", super::token_descr(&token)); + self_.struct_span_err(token.span, &msg) + }; + // On an error path, eagerly consider a lifetime to be an unclosed character lit + if self.token.is_lifetime() { + let lt = self.expect_lifetime(); + Ok(self.recover_unclosed_char(lt.ident, err)) + } else { + Err(err(self)) + } } - /// Matches `lit = true | false | token_lit`. - /// Returns `None` if the next token is not a literal. - pub(super) fn parse_opt_lit(&mut self) -> Option<Lit> { + pub(super) fn parse_token_lit(&mut self) -> PResult<'a, (token::Lit, Span)> { + self.parse_opt_token_lit() + .ok_or(()) + .or_else(|()| self.handle_missing_lit().map(|lit| (lit.token_lit, lit.span))) + } + + pub(super) fn parse_meta_item_lit(&mut self) -> PResult<'a, MetaItemLit> { + self.parse_opt_meta_item_lit().ok_or(()).or_else(|()| self.handle_missing_lit()) + } + + fn recover_after_dot(&mut self) -> Option<Token> { let mut recovered = None; if self.token == token::Dot { // Attempt to recover `.4` as `0.4`. We don't currently have any syntax where @@ -1835,100 +1841,53 @@ impl<'a> Parser<'a> { } } - let token = recovered.as_ref().unwrap_or(&self.token); - match Lit::from_token(token) { - Ok(lit) => { - self.bump(); - Some(lit) - } - Err(LitError::NotLiteral) => None, - Err(err) => { - let span = token.span; - let token::Literal(lit) = token.kind else { - unreachable!(); - }; - self.bump(); - self.report_lit_error(err, lit, span); - // Pack possible quotes and prefixes from the original literal into - // the error literal's symbol so they can be pretty-printed faithfully. - let suffixless_lit = token::Lit::new(lit.kind, lit.symbol, None); - let symbol = Symbol::intern(&suffixless_lit.to_string()); - let lit = token::Lit::new(token::Err, symbol, lit.suffix); - Some(Lit::from_token_lit(lit, span).unwrap_or_else(|_| unreachable!())) - } - } + recovered } - fn report_lit_error(&self, err: LitError, lit: token::Lit, span: Span) { - // Checks if `s` looks like i32 or u1234 etc. - fn looks_like_width_suffix(first_chars: &[char], s: &str) -> bool { - s.len() > 1 && s.starts_with(first_chars) && s[1..].chars().all(|c| c.is_ascii_digit()) - } - - // Try to lowercase the prefix if it's a valid base prefix. - fn fix_base_capitalisation(s: &str) -> Option<String> { - if let Some(stripped) = s.strip_prefix('B') { - Some(format!("0b{stripped}")) - } else if let Some(stripped) = s.strip_prefix('O') { - Some(format!("0o{stripped}")) - } else if let Some(stripped) = s.strip_prefix('X') { - Some(format!("0x{stripped}")) - } else { - None - } - } + /// Matches `lit = true | false | token_lit`. + /// Returns `None` if the next token is not a literal. + pub(super) fn parse_opt_token_lit(&mut self) -> Option<(token::Lit, Span)> { + let recovered = self.recover_after_dot(); + let token = recovered.as_ref().unwrap_or(&self.token); + let span = token.span; + token::Lit::from_token(token).map(|token_lit| { + self.bump(); + (token_lit, span) + }) + } - let token::Lit { kind, suffix, .. } = lit; - match err { - // `NotLiteral` is not an error by itself, so we don't report - // it and give the parser opportunity to try something else. - LitError::NotLiteral => {} - // `LexerError` *is* an error, but it was already reported - // by lexer, so here we don't report it the second time. - LitError::LexerError => {} - LitError::InvalidSuffix => { - if let Some(suffix) = suffix { - self.sess.emit_err(InvalidLiteralSuffix { - span, - kind: format!("{}", kind.descr()), - suffix, - }); - } - } - LitError::InvalidIntSuffix => { - let suf = suffix.expect("suffix error with no suffix"); - let suf = suf.as_str(); - if looks_like_width_suffix(&['i', 'u'], &suf) { - // If it looks like a width, try to be helpful. - self.sess.emit_err(InvalidIntLiteralWidth { span, width: suf[1..].into() }); - } else if let Some(fixed) = fix_base_capitalisation(suf) { - self.sess.emit_err(InvalidNumLiteralBasePrefix { span, fixed }); - } else { - self.sess.emit_err(InvalidNumLiteralSuffix { span, suffix: suf.to_string() }); - } - } - LitError::InvalidFloatSuffix => { - let suf = suffix.expect("suffix error with no suffix"); - let suf = suf.as_str(); - if looks_like_width_suffix(&['f'], suf) { - // If it looks like a width, try to be helpful. - self.sess - .emit_err(InvalidFloatLiteralWidth { span, width: suf[1..].to_string() }); - } else { - self.sess.emit_err(InvalidFloatLiteralSuffix { span, suffix: suf.to_string() }); + /// Matches `lit = true | false | token_lit`. + /// Returns `None` if the next token is not a literal. + pub(super) fn parse_opt_meta_item_lit(&mut self) -> Option<MetaItemLit> { + let recovered = self.recover_after_dot(); + let token = recovered.as_ref().unwrap_or(&self.token); + match token::Lit::from_token(token) { + Some(token_lit) => { + match MetaItemLit::from_token_lit(token_lit, token.span) { + Ok(lit) => { + self.bump(); + Some(lit) + } + Err(err) => { + let span = token.span; + let token::Literal(lit) = token.kind else { + unreachable!(); + }; + self.bump(); + report_lit_error(&self.sess, err, lit, span); + // Pack possible quotes and prefixes from the original literal into + // the error literal's symbol so they can be pretty-printed faithfully. + let suffixless_lit = token::Lit::new(lit.kind, lit.symbol, None); + let symbol = Symbol::intern(&suffixless_lit.to_string()); + let lit = token::Lit::new(token::Err, symbol, lit.suffix); + Some( + MetaItemLit::from_token_lit(lit, span) + .unwrap_or_else(|_| unreachable!()), + ) + } } } - LitError::NonDecimalFloat(base) => { - match base { - 16 => self.sess.emit_err(HexadecimalFloatLiteralNotSupported { span }), - 8 => self.sess.emit_err(OctalFloatLiteralNotSupported { span }), - 2 => self.sess.emit_err(BinaryFloatLiteralNotSupported { span }), - _ => unreachable!(), - }; - } - LitError::IntTooLarge => { - self.sess.emit_err(IntLiteralTooLarge { span }); - } + None => None, } } @@ -1953,8 +1912,8 @@ impl<'a> Parser<'a> { let lo = self.token.span; let minus_present = self.eat(&token::BinOp(token::Minus)); - let lit = self.parse_lit()?; - let expr = self.mk_expr(lit.span, ExprKind::Lit(lit)); + let (token_lit, span) = self.parse_token_lit()?; + let expr = self.mk_expr(span, ExprKind::Lit(token_lit)); if minus_present { Ok(self.mk_expr(lo.to(self.prev_token.span), self.mk_unary(UnOp::Neg, expr))) @@ -1999,6 +1958,10 @@ impl<'a> Parser<'a> { prev_span: Span, open_delim_span: Span, ) -> PResult<'a, ()> { + if !self.may_recover() { + return Ok(()); + } + if self.token.kind == token::Comma { if !self.sess.source_map().is_multiline(prev_span.until(self.token.span)) { return Ok(()); @@ -2039,7 +2002,7 @@ impl<'a> Parser<'a> { lo: Span, blk_mode: BlockCheckMode, ) -> PResult<'a, P<Expr>> { - if self.is_array_like_block() { + if self.may_recover() && self.is_array_like_block() { if let Some(arr) = self.maybe_suggest_brackets_instead_of_braces(lo) { return Ok(arr); } @@ -2082,15 +2045,15 @@ impl<'a> Parser<'a> { if self.eat_keyword(kw::Static) { Movability::Static } else { Movability::Movable }; let asyncness = if self.token.uninterpolated_span().rust_2018() { - self.parse_asyncness() + self.parse_asyncness(Case::Sensitive) } else { Async::No }; let capture_clause = self.parse_capture_clause()?; - let decl = self.parse_fn_block_decl()?; + let (fn_decl, fn_arg_span) = self.parse_fn_block_decl()?; let decl_hi = self.prev_token.span; - let mut body = match decl.output { + let mut body = match fn_decl.output { FnRetTy::Default(_) => { let restrictions = self.restrictions - Restrictions::STMT_EXPR; self.parse_expr_res(restrictions, None)? @@ -2109,12 +2072,7 @@ impl<'a> Parser<'a> { if self.token.kind == TokenKind::Semi && matches!(self.token_cursor.frame.delim_sp, Some((Delimiter::Parenthesis, _))) - // HACK: This is needed so we can detect whether we're inside a macro, - // where regular assumptions about what tokens can follow other tokens - // don't necessarily apply. && self.may_recover() - // FIXME(Nilstrieb): Remove this check once `may_recover` actually stops recovery - && self.subparser_name.is_none() { // It is likely that the closure body is a block but where the // braces have been removed. We will recover and eat the next @@ -2126,15 +2084,16 @@ impl<'a> Parser<'a> { let closure = self.mk_expr( lo.to(body.span), - ExprKind::Closure( + ExprKind::Closure(Box::new(ast::Closure { binder, capture_clause, asyncness, movability, - decl, + fn_decl, body, - lo.to(decl_hi), - ), + fn_decl_span: lo.to(decl_hi), + fn_arg_span, + })), ); // Disable recovery for closure body @@ -2162,7 +2121,9 @@ impl<'a> Parser<'a> { } /// Parses the `|arg, arg|` header of a closure. - fn parse_fn_block_decl(&mut self) -> PResult<'a, P<FnDecl>> { + fn parse_fn_block_decl(&mut self) -> PResult<'a, (P<FnDecl>, Span)> { + let arg_start = self.token.span.lo(); + let inputs = if self.eat(&token::OrOr) { Vec::new() } else { @@ -2178,10 +2139,11 @@ impl<'a> Parser<'a> { self.expect_or()?; args }; + let arg_span = self.prev_token.span.with_lo(arg_start); let output = self.parse_ret_ty(AllowPlus::Yes, RecoverQPath::Yes, RecoverReturnSign::Yes)?; - Ok(P(FnDecl { inputs, output })) + Ok((P(FnDecl { inputs, output }), arg_span)) } /// Parses a parameter in a closure header (e.g., `|arg, arg|`). @@ -2263,13 +2225,14 @@ impl<'a> Parser<'a> { self.mk_block_err(cond_span.shrink_to_hi()) } } else { - let attrs = self.parse_outer_attributes()?.take_for_recovery(); // For recovery. + let attrs = self.parse_outer_attributes()?; // For recovery. let block = if self.check(&token::OpenDelim(Delimiter::Brace)) { self.parse_block()? } else { if let Some(block) = recover_block_from_condition(self) { block } else { + self.error_on_extra_if(&cond)?; // Parse block, which will always fail, but we can add a nice note to the error self.parse_block().map_err(|mut err| { err.span_note( @@ -2280,7 +2243,7 @@ impl<'a> Parser<'a> { })? } }; - self.error_on_if_block_attrs(lo, false, block.span, &attrs); + self.error_on_if_block_attrs(lo, false, block.span, attrs); block }; let els = if self.eat_keyword(kw::Else) { Some(self.parse_else_expr()?) } else { None }; @@ -2321,7 +2284,15 @@ impl<'a> Parser<'a> { RecoverColon::Yes, CommaRecoveryMode::LikelyTuple, )?; - self.expect(&token::Eq)?; + if self.token == token::EqEq { + self.sess.emit_err(ExpectedEqForLetExpr { + span: self.token.span, + sugg_span: self.token.span, + }); + self.bump(); + } else { + self.expect(&token::Eq)?; + } let expr = self.with_res(self.restrictions | Restrictions::NO_STRUCT_LITERAL, |this| { this.parse_assoc_expr_with(1 + prec_let_scrutinee_needs_par(), None.into()) })?; @@ -2333,7 +2304,7 @@ impl<'a> Parser<'a> { /// Parses an `else { ... }` expression (`else` token already eaten). fn parse_else_expr(&mut self) -> PResult<'a, P<Expr>> { let else_span = self.prev_token.span; // `else` - let attrs = self.parse_outer_attributes()?.take_for_recovery(); // For recovery. + let attrs = self.parse_outer_attributes()?; // For recovery. let expr = if self.eat_keyword(kw::If) { self.parse_if_expr()? } else if self.check(&TokenKind::OpenDelim(Delimiter::Brace)) { @@ -2368,7 +2339,7 @@ impl<'a> Parser<'a> { }, } }; - self.error_on_if_block_attrs(else_span, true, expr.span, &attrs); + self.error_on_if_block_attrs(else_span, true, expr.span, attrs); Ok(expr) } @@ -2377,8 +2348,13 @@ impl<'a> Parser<'a> { ctx_span: Span, is_ctx_else: bool, branch_span: Span, - attrs: &[ast::Attribute], + attrs: AttrWrapper, ) { + if attrs.is_empty() { + return; + } + + let attrs: &[ast::Attribute] = &attrs.take_for_recovery(self.sess); let (attributes, last) = match attrs { [] => return, [x0 @ xn] | [x0, .., xn] => (x0.span.to(xn.span), xn.span), @@ -2393,6 +2369,16 @@ impl<'a> Parser<'a> { }); } + fn error_on_extra_if(&mut self, cond: &P<Expr>) -> PResult<'a, ()> { + if let ExprKind::Binary(Spanned { span: binop_span, node: binop}, _, right) = &cond.kind && + let BinOpKind::And = binop && + let ExprKind::If(cond, ..) = &right.kind { + Err(self.sess.create_err(UnexpectedIfWithIf(binop_span.shrink_to_hi().to(cond.span.shrink_to_lo())))) + } else { + Ok(()) + } + } + /// Parses `for <src_pat> in <src_expr> <src_loop_block>` (`for` token already eaten). fn parse_for_expr(&mut self, opt_label: Option<Label>, lo: Span) -> PResult<'a, P<Expr>> { // Record whether we are about to parse `for (`. @@ -2456,10 +2442,11 @@ impl<'a> Parser<'a> { /// Parses `loop { ... }` (`loop` token already eaten). fn parse_loop_expr(&mut self, opt_label: Option<Label>, lo: Span) -> PResult<'a, P<Expr>> { + let loop_span = self.prev_token.span; let (attrs, body) = self.parse_inner_attrs_and_block()?; Ok(self.mk_expr_with_attrs( lo.to(self.prev_token.span), - ExprKind::Loop(body, opt_label), + ExprKind::Loop(body, opt_label, loop_span), attrs, )) } @@ -2602,8 +2589,8 @@ impl<'a> Parser<'a> { // Used to check the `let_chains` and `if_let_guard` features mostly by scanning // `&&` tokens. fn check_let_expr(expr: &Expr) -> (bool, bool) { - match expr.kind { - ExprKind::Binary(BinOp { node: BinOpKind::And, .. }, ref lhs, ref rhs) => { + match &expr.kind { + ExprKind::Binary(BinOp { node: BinOpKind::And, .. }, lhs, rhs) => { let lhs_rslt = check_let_expr(lhs); let rhs_rslt = check_let_expr(rhs); (lhs_rslt.0 || rhs_rslt.0, false) @@ -2826,7 +2813,7 @@ impl<'a> Parser<'a> { fn maybe_parse_struct_expr( &mut self, - qself: Option<&ast::QSelf>, + qself: &Option<P<ast::QSelf>>, path: &ast::Path, ) -> Option<PResult<'a, P<Expr>>> { let struct_allowed = !self.restrictions.contains(Restrictions::NO_STRUCT_LITERAL); @@ -2834,7 +2821,7 @@ impl<'a> Parser<'a> { if let Err(err) = self.expect(&token::OpenDelim(Delimiter::Brace)) { return Some(Err(err)); } - let expr = self.parse_struct_expr(qself.cloned(), path.clone(), true); + let expr = self.parse_struct_expr(qself.clone(), path.clone(), true); if let (Ok(expr), false) = (&expr, struct_allowed) { // This is a struct literal, but we don't can't accept them here. self.sess.emit_err(StructLiteralNotAllowedHere { @@ -2867,7 +2854,7 @@ impl<'a> Parser<'a> { }; while self.token != token::CloseDelim(close_delim) { - if self.eat(&token::DotDot) { + if self.eat(&token::DotDot) || self.recover_struct_field_dots(close_delim) { let exp_span = self.prev_token.span; // We permit `.. }` on the left-hand side of a destructuring assignment. if self.check(&token::CloseDelim(close_delim)) { @@ -2965,7 +2952,7 @@ impl<'a> Parser<'a> { /// Precondition: already parsed the '{'. pub(super) fn parse_struct_expr( &mut self, - qself: Option<ast::QSelf>, + qself: Option<P<ast::QSelf>>, pth: ast::Path, recover: bool, ) -> PResult<'a, P<Expr>> { @@ -3014,6 +3001,18 @@ impl<'a> Parser<'a> { self.recover_stmt(); } + fn recover_struct_field_dots(&mut self, close_delim: Delimiter) -> bool { + if !self.look_ahead(1, |t| *t == token::CloseDelim(close_delim)) + && self.eat(&token::DotDotDot) + { + // recover from typo of `...`, suggest `..` + let span = self.prev_token.span; + self.sess.emit_err(MissingDotDot { token_span: span, sugg_span: span }); + return true; + } + false + } + /// Parses `ident (COLON expr)?`. fn parse_expr_field(&mut self) -> PResult<'a, ExprField> { let attrs = self.parse_outer_attributes()?; diff --git a/compiler/rustc_parse/src/parser/item.rs b/compiler/rustc_parse/src/parser/item.rs index bda301c52..03f25392a 100644 --- a/compiler/rustc_parse/src/parser/item.rs +++ b/compiler/rustc_parse/src/parser/item.rs @@ -3,17 +3,17 @@ use crate::errors::{DocCommentDoesNotDocumentAnything, UseEmptyBlockNotSemi}; use super::diagnostics::{dummy_arg, ConsumeClosingDelim}; use super::ty::{AllowPlus, RecoverQPath, RecoverReturnSign}; use super::{AttrWrapper, FollowedByType, ForceCollect, Parser, PathStyle, TrailingToken}; - use rustc_ast::ast::*; use rustc_ast::ptr::P; use rustc_ast::token::{self, Delimiter, TokenKind}; use rustc_ast::tokenstream::{DelimSpan, TokenStream, TokenTree}; +use rustc_ast::util::case::Case; use rustc_ast::{self as ast, AttrVec, Attribute, DUMMY_NODE_ID}; use rustc_ast::{Async, Const, Defaultness, IsAuto, Mutability, Unsafe, UseTree, UseTreeKind}; use rustc_ast::{BindingAnnotation, Block, FnDecl, FnSig, Param, SelfKind}; use rustc_ast::{EnumDef, FieldDef, Generics, TraitRef, Ty, TyKind, Variant, VariantData}; use rustc_ast::{FnHeader, ForeignItem, Path, PathSegment, Visibility, VisibilityKind}; -use rustc_ast::{MacArgs, MacCall, MacDelimiter}; +use rustc_ast::{MacCall, MacDelimiter}; use rustc_ast_pretty::pprust; use rustc_errors::{struct_span_err, Applicability, IntoDiagnostic, PResult, StashKey}; use rustc_span::edition::Edition; @@ -21,9 +21,10 @@ use rustc_span::lev_distance::lev_distance; use rustc_span::source_map::{self, Span}; use rustc_span::symbol::{kw, sym, Ident, Symbol}; use rustc_span::DUMMY_SP; - use std::convert::TryFrom; use std::mem; +use thin_vec::ThinVec; +use tracing::debug; impl<'a> Parser<'a> { /// Parses a source module as a crate. This is the main entry point for the parser. @@ -34,7 +35,7 @@ impl<'a> Parser<'a> { /// Parses a `mod <foo> { ... }` or `mod <foo>;` item. fn parse_item_mod(&mut self, attrs: &mut AttrVec) -> PResult<'a, ItemInfo> { - let unsafety = self.parse_unsafety(); + let unsafety = self.parse_unsafety(Case::Sensitive); self.expect_keyword(kw::Mod)?; let id = self.parse_ident()?; let mod_kind = if self.eat(&token::Semi) { @@ -143,8 +144,15 @@ impl<'a> Parser<'a> { let lo = self.token.span; let vis = self.parse_visibility(FollowedByType::No)?; let mut def = self.parse_defaultness(); - let kind = - self.parse_item_kind(&mut attrs, mac_allowed, lo, &vis, &mut def, fn_parse_mode)?; + let kind = self.parse_item_kind( + &mut attrs, + mac_allowed, + lo, + &vis, + &mut def, + fn_parse_mode, + Case::Sensitive, + )?; if let Some((ident, kind)) = kind { self.error_on_unconsumed_default(def, &kind); let span = lo.to(self.prev_token.span); @@ -205,16 +213,18 @@ impl<'a> Parser<'a> { vis: &Visibility, def: &mut Defaultness, fn_parse_mode: FnParseMode, + case: Case, ) -> PResult<'a, Option<ItemInfo>> { let def_final = def == &Defaultness::Final; - let mut def = || mem::replace(def, Defaultness::Final); + let mut def_ = || mem::replace(def, Defaultness::Final); - let info = if self.eat_keyword(kw::Use) { + let info = if self.eat_keyword_case(kw::Use, case) { self.parse_use_item()? - } else if self.check_fn_front_matter(def_final) { + } else if self.check_fn_front_matter(def_final, case) { // FUNCTION ITEM - let (ident, sig, generics, body) = self.parse_fn(attrs, fn_parse_mode, lo, vis)?; - (ident, ItemKind::Fn(Box::new(Fn { defaultness: def(), sig, generics, body }))) + let (ident, sig, generics, body) = + self.parse_fn(attrs, fn_parse_mode, lo, vis, case)?; + (ident, ItemKind::Fn(Box::new(Fn { defaultness: def_(), sig, generics, body }))) } else if self.eat_keyword(kw::Extern) { if self.eat_keyword(kw::Crate) { // EXTERN CRATE @@ -225,7 +235,7 @@ impl<'a> Parser<'a> { } } else if self.is_unsafe_foreign_mod() { // EXTERN BLOCK - let unsafety = self.parse_unsafety(); + let unsafety = self.parse_unsafety(Case::Sensitive); self.expect_keyword(kw::Extern)?; self.parse_item_foreign_mod(attrs, unsafety)? } else if self.is_static_global() { @@ -234,15 +244,15 @@ impl<'a> Parser<'a> { let m = self.parse_mutability(); let (ident, ty, expr) = self.parse_item_global(Some(m))?; (ident, ItemKind::Static(ty, m, expr)) - } else if let Const::Yes(const_span) = self.parse_constness() { + } else if let Const::Yes(const_span) = self.parse_constness(Case::Sensitive) { // CONST ITEM if self.token.is_keyword(kw::Impl) { // recover from `const impl`, suggest `impl const` - self.recover_const_impl(const_span, attrs, def())? + self.recover_const_impl(const_span, attrs, def_())? } else { self.recover_const_mut(const_span); let (ident, ty, expr) = self.parse_item_global(None)?; - (ident, ItemKind::Const(def(), ty, expr)) + (ident, ItemKind::Const(def_(), ty, expr)) } } else if self.check_keyword(kw::Trait) || self.check_auto_or_unsafe_trait_item() { // TRAIT ITEM @@ -251,7 +261,7 @@ impl<'a> Parser<'a> { || self.check_keyword(kw::Unsafe) && self.is_keyword_ahead(1, &[kw::Impl]) { // IMPL ITEM - self.parse_item_impl(attrs, def())? + self.parse_item_impl(attrs, def_())? } else if self.check_keyword(kw::Mod) || self.check_keyword(kw::Unsafe) && self.is_keyword_ahead(1, &[kw::Mod]) { @@ -259,7 +269,7 @@ impl<'a> Parser<'a> { self.parse_item_mod(attrs)? } else if self.eat_keyword(kw::Type) { // TYPE ITEM - self.parse_type_alias(def())? + self.parse_type_alias(def_())? } else if self.eat_keyword(kw::Enum) { // ENUM ITEM self.parse_item_enum()? @@ -286,6 +296,19 @@ impl<'a> Parser<'a> { } else if self.isnt_macro_invocation() && vis.kind.is_pub() { self.recover_missing_kw_before_item()?; return Ok(None); + } else if self.isnt_macro_invocation() && case == Case::Sensitive { + _ = def_; + + // Recover wrong cased keywords + return self.parse_item_kind( + attrs, + macros_allowed, + lo, + vis, + def, + fn_parse_mode, + Case::Insensitive, + ); } else if macros_allowed && self.check_path() { // MACRO INVOCATION ITEM (Ident::empty(), ItemKind::MacCall(P(self.parse_item_macro(vis)?))) @@ -449,7 +472,7 @@ impl<'a> Parser<'a> { fn parse_item_macro(&mut self, vis: &Visibility) -> PResult<'a, MacCall> { let path = self.parse_path(PathStyle::Mod)?; // `foo::bar` self.expect(&token::Not)?; // `!` - match self.parse_mac_args() { + match self.parse_delim_args() { // `( .. )` or `[ .. ]` (followed by `;`), or `{ .. }`. Ok(args) => { self.eat_semi_for_macro_if_needed(&args); @@ -538,7 +561,7 @@ impl<'a> Parser<'a> { attrs: &mut AttrVec, defaultness: Defaultness, ) -> PResult<'a, ItemInfo> { - let unsafety = self.parse_unsafety(); + let unsafety = self.parse_unsafety(Case::Sensitive); self.expect_keyword(kw::Impl)?; // First, parse generic parameters if necessary. @@ -552,7 +575,7 @@ impl<'a> Parser<'a> { generics }; - let constness = self.parse_constness(); + let constness = self.parse_constness(Case::Sensitive); if let Const::Yes(span) = constness { self.sess.gated_spans.gate(sym::const_trait_impl, span); } @@ -796,7 +819,7 @@ impl<'a> Parser<'a> { /// Parses `unsafe? auto? trait Foo { ... }` or `trait Foo = Bar;`. fn parse_item_trait(&mut self, attrs: &mut AttrVec, lo: Span) -> PResult<'a, ItemInfo> { - let unsafety = self.parse_unsafety(); + let unsafety = self.parse_unsafety(Case::Sensitive); // Parse optional `auto` prefix. let is_auto = if self.eat_keyword(kw::Auto) { IsAuto::Yes } else { IsAuto::No }; @@ -950,7 +973,8 @@ impl<'a> Parser<'a> { fn parse_use_tree(&mut self) -> PResult<'a, UseTree> { let lo = self.token.span; - let mut prefix = ast::Path { segments: Vec::new(), span: lo.shrink_to_lo(), tokens: None }; + let mut prefix = + ast::Path { segments: ThinVec::new(), span: lo.shrink_to_lo(), tokens: None }; let kind = if self.check(&token::OpenDelim(Delimiter::Brace)) || self.check(&token::BinOp(token::Star)) || self.is_import_coupler() @@ -971,7 +995,24 @@ impl<'a> Parser<'a> { if self.eat(&token::ModSep) { self.parse_use_tree_glob_or_nested()? } else { - UseTreeKind::Simple(self.parse_rename()?, DUMMY_NODE_ID, DUMMY_NODE_ID) + // Recover from using a colon as path separator. + while self.eat_noexpect(&token::Colon) { + self.struct_span_err(self.prev_token.span, "expected `::`, found `:`") + .span_suggestion_short( + self.prev_token.span, + "use double colon", + "::", + Applicability::MachineApplicable, + ) + .note_once("import paths are delimited using `::`") + .emit(); + + // We parse the rest of the path and append it to the original prefix. + self.parse_path_segments(&mut prefix.segments, PathStyle::Mod, None)?; + prefix.span = lo.to(self.prev_token.span); + } + + UseTreeKind::Simple(self.parse_rename()?) } }; @@ -1215,8 +1256,8 @@ impl<'a> Parser<'a> { } }; - match impl_info.1 { - ItemKind::Impl(box Impl { of_trait: Some(ref trai), ref mut constness, .. }) => { + match &mut impl_info.1 { + ItemKind::Impl(box Impl { of_trait: Some(trai), constness, .. }) => { *constness = Const::Yes(const_span); let before_trait = trai.path.span.shrink_to_lo(); @@ -1373,7 +1414,10 @@ impl<'a> Parser<'a> { Ok((Some(vr), TrailingToken::MaybeComma)) }, - ) + ).map_err(|mut err|{ + err.help("enum variants can be `Variant`, `Variant = <integer>`, `Variant(Type, ..., TypeN)` or `Variant { fields: Types }`"); + err + }) } /// Parses `struct Foo { ... }`. @@ -1745,7 +1789,7 @@ impl<'a> Parser<'a> { let (ident, is_raw) = self.ident_or_err()?; if !is_raw && ident.is_reserved() { let snapshot = self.create_snapshot_for_diagnostic(); - let err = if self.check_fn_front_matter(false) { + let err = if self.check_fn_front_matter(false, Case::Sensitive) { let inherited_vis = Visibility { span: rustc_span::DUMMY_SP, kind: VisibilityKind::Inherited, @@ -1753,7 +1797,13 @@ impl<'a> Parser<'a> { }; // We use `parse_fn` to get a span for the function let fn_parse_mode = FnParseMode { req_name: |_| true, req_body: true }; - match self.parse_fn(&mut AttrVec::new(), fn_parse_mode, lo, &inherited_vis) { + match self.parse_fn( + &mut AttrVec::new(), + fn_parse_mode, + lo, + &inherited_vis, + Case::Insensitive, + ) { Ok(_) => { let mut err = self.struct_span_err( lo.to(self.prev_token.span), @@ -1827,7 +1877,7 @@ impl<'a> Parser<'a> { fn parse_item_decl_macro(&mut self, lo: Span) -> PResult<'a, ItemInfo> { let ident = self.parse_ident()?; let body = if self.check(&token::OpenDelim(Delimiter::Brace)) { - self.parse_mac_args()? // `MacBody` + self.parse_delim_args()? // `MacBody` } else if self.check(&token::OpenDelim(Delimiter::Parenthesis)) { let params = self.parse_token_tree(); // `MacParams` let pspan = params.span(); @@ -1840,7 +1890,7 @@ impl<'a> Parser<'a> { let arrow = TokenTree::token_alone(token::FatArrow, pspan.between(bspan)); // `=>` let tokens = TokenStream::new(vec![params, arrow, body]); let dspan = DelimSpan::from_pair(pspan.shrink_to_lo(), bspan.shrink_to_hi()); - P(MacArgs::Delimited(dspan, MacDelimiter::Brace, tokens)) + P(DelimArgs { dspan, delim: MacDelimiter::Brace, tokens }) } else { return self.unexpected(); }; @@ -1895,7 +1945,7 @@ impl<'a> Parser<'a> { .emit(); } - let body = self.parse_mac_args()?; + let body = self.parse_delim_args()?; self.eat_semi_for_macro_if_needed(&body); self.complain_if_pub_macro(vis, true); @@ -1934,14 +1984,14 @@ impl<'a> Parser<'a> { } } - fn eat_semi_for_macro_if_needed(&mut self, args: &MacArgs) { + fn eat_semi_for_macro_if_needed(&mut self, args: &DelimArgs) { if args.need_semicolon() && !self.eat(&token::Semi) { self.report_invalid_macro_expansion_item(args); } } - fn report_invalid_macro_expansion_item(&self, args: &MacArgs) { - let span = args.span().expect("undelimited macro call"); + fn report_invalid_macro_expansion_item(&self, args: &DelimArgs) { + let span = args.dspan.entire(); let mut err = self.struct_span_err( span, "macros that expand to items must be delimited with braces or followed by a semicolon", @@ -1950,10 +2000,7 @@ impl<'a> Parser<'a> { // macros within the same crate (that we can fix), which is sad. if !span.from_expansion() { if self.unclosed_delims.is_empty() { - let DelimSpan { open, close } = match args { - MacArgs::Empty | MacArgs::Eq(..) => unreachable!(), - MacArgs::Delimited(dspan, ..) => *dspan, - }; + let DelimSpan { open, close } = args.dspan; err.multipart_suggestion( "change the delimiters to curly braces", vec![(open, "{".to_string()), (close, '}'.to_string())], @@ -2077,8 +2124,9 @@ impl<'a> Parser<'a> { fn_parse_mode: FnParseMode, sig_lo: Span, vis: &Visibility, + case: Case, ) -> PResult<'a, (Ident, FnSig, Generics, Option<P<Block>>)> { - let header = self.parse_fn_front_matter(vis)?; // `const ... fn` + let header = self.parse_fn_front_matter(vis, case)?; // `const ... fn` let ident = self.parse_ident()?; // `foo` let mut generics = self.parse_generics()?; // `<'a, T, ...>` let decl = @@ -2155,7 +2203,7 @@ impl<'a> Parser<'a> { /// /// `check_pub` adds additional `pub` to the checks in case users place it /// wrongly, can be used to ensure `pub` never comes after `default`. - pub(super) fn check_fn_front_matter(&mut self, check_pub: bool) -> bool { + pub(super) fn check_fn_front_matter(&mut self, check_pub: bool, case: Case) -> bool { // We use an over-approximation here. // `const const`, `fn const` won't parse, but we're not stepping over other syntax either. // `pub` is added in case users got confused with the ordering like `async pub fn`, @@ -2165,23 +2213,30 @@ impl<'a> Parser<'a> { } else { &[kw::Const, kw::Async, kw::Unsafe, kw::Extern] }; - self.check_keyword(kw::Fn) // Definitely an `fn`. + self.check_keyword_case(kw::Fn, case) // Definitely an `fn`. // `$qual fn` or `$qual $qual`: - || quals.iter().any(|&kw| self.check_keyword(kw)) + || quals.iter().any(|&kw| self.check_keyword_case(kw, case)) && self.look_ahead(1, |t| { // `$qual fn`, e.g. `const fn` or `async fn`. - t.is_keyword(kw::Fn) + t.is_keyword_case(kw::Fn, case) // Two qualifiers `$qual $qual` is enough, e.g. `async unsafe`. - || t.is_non_raw_ident_where(|i| quals.contains(&i.name) - // Rule out 2015 `const async: T = val`. - && i.is_reserved() + || ( + ( + t.is_non_raw_ident_where(|i| + quals.contains(&i.name) + // Rule out 2015 `const async: T = val`. + && i.is_reserved() + ) + || case == Case::Insensitive + && t.is_non_raw_ident_where(|i| quals.iter().any(|qual| qual.as_str() == i.name.as_str().to_lowercase())) + ) // Rule out unsafe extern block. && !self.is_unsafe_foreign_mod()) }) // `extern ABI fn` - || self.check_keyword(kw::Extern) + || self.check_keyword_case(kw::Extern, case) && self.look_ahead(1, |t| t.can_begin_literal_maybe_minus()) - && self.look_ahead(2, |t| t.is_keyword(kw::Fn)) + && self.look_ahead(2, |t| t.is_keyword_case(kw::Fn, case)) } /// Parses all the "front matter" (or "qualifiers") for a `fn` declaration, @@ -2195,24 +2250,28 @@ impl<'a> Parser<'a> { /// /// `vis` represents the visibility that was already parsed, if any. Use /// `Visibility::Inherited` when no visibility is known. - pub(super) fn parse_fn_front_matter(&mut self, orig_vis: &Visibility) -> PResult<'a, FnHeader> { + pub(super) fn parse_fn_front_matter( + &mut self, + orig_vis: &Visibility, + case: Case, + ) -> PResult<'a, FnHeader> { let sp_start = self.token.span; - let constness = self.parse_constness(); + let constness = self.parse_constness(case); let async_start_sp = self.token.span; - let asyncness = self.parse_asyncness(); + let asyncness = self.parse_asyncness(case); let unsafe_start_sp = self.token.span; - let unsafety = self.parse_unsafety(); + let unsafety = self.parse_unsafety(case); let ext_start_sp = self.token.span; - let ext = self.parse_extern(); + let ext = self.parse_extern(case); if let Async::Yes { span, .. } = asyncness { self.ban_async_in_2015(span); } - if !self.eat_keyword(kw::Fn) { + if !self.eat_keyword_case(kw::Fn, case) { // It is possible for `expect_one_of` to recover given the contents of // `self.expected_tokens`, therefore, do not use `self.unexpected()` which doesn't // account for this. @@ -2541,8 +2600,8 @@ impl<'a> Parser<'a> { } fn is_named_param(&self) -> bool { - let offset = match self.token.kind { - token::Interpolated(ref nt) => match **nt { + let offset = match &self.token.kind { + token::Interpolated(nt) => match **nt { token::NtPat(..) => return self.look_ahead(1, |t| t == &token::Colon), _ => 0, }, diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs index 5fe29062b..bebb01266 100644 --- a/compiler/rustc_parse/src/parser/mod.rs +++ b/compiler/rustc_parse/src/parser/mod.rs @@ -22,10 +22,11 @@ use rustc_ast::token::{self, Delimiter, Nonterminal, Token, TokenKind}; use rustc_ast::tokenstream::AttributesData; use rustc_ast::tokenstream::{self, DelimSpan, Spacing}; use rustc_ast::tokenstream::{TokenStream, TokenTree}; +use rustc_ast::util::case::Case; use rustc_ast::AttrId; use rustc_ast::DUMMY_NODE_ID; -use rustc_ast::{self as ast, AnonConst, AttrStyle, AttrVec, Const, Extern}; -use rustc_ast::{Async, Expr, ExprKind, MacArgs, MacArgsEq, MacDelimiter, Mutability, StrLit}; +use rustc_ast::{self as ast, AnonConst, AttrStyle, AttrVec, Const, DelimArgs, Extern}; +use rustc_ast::{Async, AttrArgs, AttrArgsEq, Expr, ExprKind, MacDelimiter, Mutability, StrLit}; use rustc_ast::{HasAttrs, HasTokens, Unsafe, Visibility, VisibilityKind}; use rustc_ast_pretty::pprust; use rustc_data_structures::fx::FxHashMap; @@ -104,6 +105,7 @@ macro_rules! maybe_whole { macro_rules! maybe_recover_from_interpolated_ty_qpath { ($self: expr, $allow_qpath_recovery: expr) => { if $allow_qpath_recovery + && $self.may_recover() && $self.look_ahead(1, |t| t == &token::ModSep) && let token::Interpolated(nt) = &$self.token.kind && let token::NtTy(ty) = &**nt @@ -382,8 +384,8 @@ enum TokenType { impl TokenType { fn to_string(&self) -> String { - match *self { - TokenType::Token(ref t) => format!("`{}`", pprust::token_kind_to_string(t)), + match self { + TokenType::Token(t) => format!("`{}`", pprust::token_kind_to_string(t)), TokenType::Keyword(kw) => format!("`{}`", kw), TokenType::Operator => "an operator".to_string(), TokenType::Lifetime => "lifetime".to_string(), @@ -501,8 +503,8 @@ impl<'a> Parser<'a> { parser } - pub fn forbid_recovery(mut self) -> Self { - self.recovery = Recovery::Forbidden; + pub fn recovery(mut self, recovery: Recovery) -> Self { + self.recovery = recovery; self } @@ -635,6 +637,20 @@ impl<'a> Parser<'a> { self.token.is_keyword(kw) } + fn check_keyword_case(&mut self, kw: Symbol, case: Case) -> bool { + if self.check_keyword(kw) { + return true; + } + + if case == Case::Insensitive + && let Some((ident, /* is_raw */ false)) = self.token.ident() + && ident.as_str().to_lowercase() == kw.as_str().to_lowercase() { + true + } else { + false + } + } + /// If the next token is the given keyword, eats it and returns `true`. /// Otherwise, returns `false`. An expectation is also added for diagnostics purposes. // Public for rustfmt usage. @@ -647,6 +663,33 @@ impl<'a> Parser<'a> { } } + /// Eats a keyword, optionally ignoring the case. + /// If the case differs (and is ignored) an error is issued. + /// This is useful for recovery. + fn eat_keyword_case(&mut self, kw: Symbol, case: Case) -> bool { + if self.eat_keyword(kw) { + return true; + } + + if case == Case::Insensitive + && let Some((ident, /* is_raw */ false)) = self.token.ident() + && ident.as_str().to_lowercase() == kw.as_str().to_lowercase() { + self + .struct_span_err(ident.span, format!("keyword `{kw}` is written in a wrong case")) + .span_suggestion( + ident.span, + "write it in the correct case", + kw, + Applicability::MachineApplicable + ).emit(); + + self.bump(); + return true; + } + + false + } + fn eat_keyword_noexpect(&mut self, kw: Symbol) -> bool { if self.token.is_keyword(kw) { self.bump(); @@ -695,8 +738,8 @@ impl<'a> Parser<'a> { fn check_inline_const(&self, dist: usize) -> bool { self.is_keyword_ahead(dist, &[kw::Const]) - && self.look_ahead(dist + 1, |t| match t.kind { - token::Interpolated(ref nt) => matches!(**nt, token::NtBlock(..)), + && self.look_ahead(dist + 1, |t| match &t.kind { + token::Interpolated(nt) => matches!(**nt, token::NtBlock(..)), token::OpenDelim(Delimiter::Brace) => true, _ => false, }) @@ -817,7 +860,7 @@ impl<'a> Parser<'a> { if let token::CloseDelim(..) | token::Eof = self.token.kind { break; } - if let Some(ref t) = sep.sep { + if let Some(t) = &sep.sep { if first { first = false; } else { @@ -852,7 +895,7 @@ impl<'a> Parser<'a> { _ => { // Attempt to keep parsing if it was a similar separator. - if let Some(ref tokens) = t.similar_tokens() { + if let Some(tokens) = t.similar_tokens() { if tokens.contains(&self.token.kind) && !unclosed_delims { self.bump(); } @@ -900,6 +943,10 @@ impl<'a> Parser<'a> { Err(e) => { // Parsing failed, therefore it must be something more serious // than just a missing separator. + for xx in &e.children { + // propagate the help message from sub error 'e' to main error 'expect_err; + expect_err.children.push(xx.clone()); + } expect_err.emit(); e.cancel(); @@ -1126,8 +1173,8 @@ impl<'a> Parser<'a> { } /// Parses asyncness: `async` or nothing. - fn parse_asyncness(&mut self) -> Async { - if self.eat_keyword(kw::Async) { + fn parse_asyncness(&mut self, case: Case) -> Async { + if self.eat_keyword_case(kw::Async, case) { let span = self.prev_token.uninterpolated_span(); Async::Yes { span, closure_id: DUMMY_NODE_ID, return_impl_trait_id: DUMMY_NODE_ID } } else { @@ -1136,8 +1183,8 @@ impl<'a> Parser<'a> { } /// Parses unsafety: `unsafe` or nothing. - fn parse_unsafety(&mut self) -> Unsafe { - if self.eat_keyword(kw::Unsafe) { + fn parse_unsafety(&mut self, case: Case) -> Unsafe { + if self.eat_keyword_case(kw::Unsafe, case) { Unsafe::Yes(self.prev_token.uninterpolated_span()) } else { Unsafe::No @@ -1145,10 +1192,10 @@ impl<'a> Parser<'a> { } /// Parses constness: `const` or nothing. - fn parse_constness(&mut self) -> Const { + fn parse_constness(&mut self, case: Case) -> Const { // Avoid const blocks to be parsed as const items if self.look_ahead(1, |t| t != &token::OpenDelim(Delimiter::Brace)) - && self.eat_keyword(kw::Const) + && self.eat_keyword_case(kw::Const, case) { Const::Yes(self.prev_token.uninterpolated_span()) } else { @@ -1206,39 +1253,40 @@ impl<'a> Parser<'a> { } } - fn parse_mac_args(&mut self) -> PResult<'a, P<MacArgs>> { - self.parse_mac_args_common(true).map(P) + fn parse_delim_args(&mut self) -> PResult<'a, P<DelimArgs>> { + if let Some(args) = self.parse_delim_args_inner() { Ok(P(args)) } else { self.unexpected() } } - fn parse_attr_args(&mut self) -> PResult<'a, MacArgs> { - self.parse_mac_args_common(false) + fn parse_attr_args(&mut self) -> PResult<'a, AttrArgs> { + Ok(if let Some(args) = self.parse_delim_args_inner() { + AttrArgs::Delimited(args) + } else { + if self.eat(&token::Eq) { + let eq_span = self.prev_token.span; + AttrArgs::Eq(eq_span, AttrArgsEq::Ast(self.parse_expr_force_collect()?)) + } else { + AttrArgs::Empty + } + }) } - fn parse_mac_args_common(&mut self, delimited_only: bool) -> PResult<'a, MacArgs> { - Ok( - if self.check(&token::OpenDelim(Delimiter::Parenthesis)) - || self.check(&token::OpenDelim(Delimiter::Bracket)) - || self.check(&token::OpenDelim(Delimiter::Brace)) - { - match self.parse_token_tree() { - TokenTree::Delimited(dspan, delim, tokens) => - // We've confirmed above that there is a delimiter so unwrapping is OK. - { - MacArgs::Delimited(dspan, MacDelimiter::from_token(delim).unwrap(), tokens) - } - _ => unreachable!(), - } - } else if !delimited_only { - if self.eat(&token::Eq) { - let eq_span = self.prev_token.span; - MacArgs::Eq(eq_span, MacArgsEq::Ast(self.parse_expr_force_collect()?)) - } else { - MacArgs::Empty - } - } else { - return self.unexpected(); - }, - ) + fn parse_delim_args_inner(&mut self) -> Option<DelimArgs> { + if self.check(&token::OpenDelim(Delimiter::Parenthesis)) + || self.check(&token::OpenDelim(Delimiter::Bracket)) + || self.check(&token::OpenDelim(Delimiter::Brace)) + { + match self.parse_token_tree() { + // We've confirmed above that there is a delimiter so unwrapping is OK. + TokenTree::Delimited(dspan, delim, tokens) => Some(DelimArgs { + dspan, + delim: MacDelimiter::from_token(delim).unwrap(), + tokens, + }), + _ => unreachable!(), + } + } else { + None + } } fn parse_or_use_outer_attributes( @@ -1403,8 +1451,8 @@ impl<'a> Parser<'a> { } /// Parses `extern string_literal?`. - fn parse_extern(&mut self) -> Extern { - if self.eat_keyword(kw::Extern) { + fn parse_extern(&mut self, case: Case) -> Extern { + if self.eat_keyword_case(kw::Extern, case) { let mut extern_span = self.prev_token.span; let abi = self.parse_abi(); if let Some(abi) = abi { diff --git a/compiler/rustc_parse/src/parser/nonterminal.rs b/compiler/rustc_parse/src/parser/nonterminal.rs index 103dd8012..239ed79ce 100644 --- a/compiler/rustc_parse/src/parser/nonterminal.rs +++ b/compiler/rustc_parse/src/parser/nonterminal.rs @@ -42,9 +42,9 @@ impl<'a> Parser<'a> { token::Comma | token::Ident(..) | token::Interpolated(..) => true, _ => token.can_begin_type(), }, - NonterminalKind::Block => match token.kind { + NonterminalKind::Block => match &token.kind { token::OpenDelim(Delimiter::Brace) => true, - token::Interpolated(ref nt) => !matches!( + token::Interpolated(nt) => !matches!( **nt, token::NtItem(_) | token::NtPat(_) @@ -56,16 +56,16 @@ impl<'a> Parser<'a> { ), _ => false, }, - NonterminalKind::Path | NonterminalKind::Meta => match token.kind { + NonterminalKind::Path | NonterminalKind::Meta => match &token.kind { token::ModSep | token::Ident(..) => true, - token::Interpolated(ref nt) => match **nt { + token::Interpolated(nt) => match **nt { token::NtPath(_) | token::NtMeta(_) => true, _ => may_be_ident(&nt), }, _ => false, }, NonterminalKind::PatParam { .. } | NonterminalKind::PatWithOr { .. } => { - match token.kind { + match &token.kind { token::Ident(..) | // box, ref, mut, and other identifiers (can stricten) token::OpenDelim(Delimiter::Parenthesis) | // tuple pattern token::OpenDelim(Delimiter::Bracket) | // slice pattern @@ -80,13 +80,13 @@ impl<'a> Parser<'a> { token::BinOp(token::Shl) => true, // path (double UFCS) // leading vert `|` or-pattern token::BinOp(token::Or) => matches!(kind, NonterminalKind::PatWithOr {..}), - token::Interpolated(ref nt) => may_be_ident(nt), + token::Interpolated(nt) => may_be_ident(nt), _ => false, } } - NonterminalKind::Lifetime => match token.kind { + NonterminalKind::Lifetime => match &token.kind { token::Lifetime(_) => true, - token::Interpolated(ref nt) => { + token::Interpolated(nt) => { matches!(**nt, token::NtLifetime(_)) } _ => false, diff --git a/compiler/rustc_parse/src/parser/pat.rs b/compiler/rustc_parse/src/parser/pat.rs index 52c11b4e3..cbeec951e 100644 --- a/compiler/rustc_parse/src/parser/pat.rs +++ b/compiler/rustc_parse/src/parser/pat.rs @@ -420,7 +420,7 @@ impl<'a> Parser<'a> { err.span_label(self_.token.span, format!("expected {}", expected)); err }); - PatKind::Lit(self.mk_expr(lo, ExprKind::Lit(lit))) + PatKind::Lit(self.mk_expr(lo, ExprKind::Lit(lit.token_lit))) } else { // Try to parse everything else as literal with optional minus match self.parse_literal_maybe_minus() { @@ -485,7 +485,7 @@ impl<'a> Parser<'a> { let mut rhs = self.parse_pat_no_top_alt(None)?; let sp = lhs.span.to(rhs.span); - if let PatKind::Ident(_, _, ref mut sub @ None) = rhs.kind { + if let PatKind::Ident(_, _, sub @ None) = &mut rhs.kind { // The user inverted the order, so help them fix that. let mut applicability = Applicability::MachineApplicable; // FIXME(bindings_after_at): Remove this code when stabilizing the feature. @@ -595,7 +595,7 @@ impl<'a> Parser<'a> { self.recover_additional_muts(); // Make sure we don't allow e.g. `let mut $p;` where `$p:pat`. - if let token::Interpolated(ref nt) = self.token.kind { + if let token::Interpolated(nt) = &self.token.kind { if let token::NtPat(_) = **nt { self.expected_ident_found().emit(); } @@ -693,7 +693,7 @@ impl<'a> Parser<'a> { /// Parse macro invocation fn parse_pat_mac_invoc(&mut self, path: Path) -> PResult<'a, PatKind> { self.bump(); - let args = self.parse_mac_args()?; + let args = self.parse_delim_args()?; let mac = P(MacCall { path, args, prior_type_ascription: self.last_type_ascription }); Ok(PatKind::MacCall(mac)) } @@ -796,7 +796,7 @@ impl<'a> Parser<'a> { /// expression syntax `...expr` for splatting in expressions. fn parse_pat_range_to(&mut self, mut re: Spanned<RangeEnd>) -> PResult<'a, PatKind> { let end = self.parse_pat_range_end()?; - if let RangeEnd::Included(ref mut syn @ RangeSyntax::DotDotDot) = &mut re.node { + if let RangeEnd::Included(syn @ RangeSyntax::DotDotDot) = &mut re.node { *syn = RangeSyntax::DotDotEq; self.struct_span_err(re.span, "range-to patterns with `...` are not allowed") .span_suggestion_short( @@ -889,7 +889,7 @@ impl<'a> Parser<'a> { } /// Parse a struct ("record") pattern (e.g. `Foo { ... }` or `Foo::Bar { ... }`). - fn parse_pat_struct(&mut self, qself: Option<QSelf>, path: Path) -> PResult<'a, PatKind> { + fn parse_pat_struct(&mut self, qself: Option<P<QSelf>>, path: Path) -> PResult<'a, PatKind> { if qself.is_some() { // Feature gate the use of qualified paths in patterns self.sess.gated_spans.gate(sym::more_qualified_paths, path.span); @@ -906,7 +906,11 @@ impl<'a> Parser<'a> { } /// Parse tuple struct or tuple variant pattern (e.g. `Foo(...)` or `Foo::Bar(...)`). - fn parse_pat_tuple_struct(&mut self, qself: Option<QSelf>, path: Path) -> PResult<'a, PatKind> { + fn parse_pat_tuple_struct( + &mut self, + qself: Option<P<QSelf>>, + path: Path, + ) -> PResult<'a, PatKind> { let (fields, _) = self.parse_paren_comma_seq(|p| { p.parse_pat_allow_top_alt( None, diff --git a/compiler/rustc_parse/src/parser/path.rs b/compiler/rustc_parse/src/parser/path.rs index fdc1af27f..2d432e3f5 100644 --- a/compiler/rustc_parse/src/parser/path.rs +++ b/compiler/rustc_parse/src/parser/path.rs @@ -11,8 +11,9 @@ use rustc_ast::{ use rustc_errors::{pluralize, Applicability, PResult}; use rustc_span::source_map::{BytePos, Span}; use rustc_span::symbol::{kw, sym, Ident}; - use std::mem; +use thin_vec::ThinVec; +use tracing::debug; /// Specifies how to parse a path. #[derive(Copy, Clone, PartialEq)] @@ -48,7 +49,7 @@ impl<'a> Parser<'a> { /// `<T as U>::a` /// `<T as U>::F::a<S>` (without disambiguator) /// `<T as U>::F::a::<S>` (with disambiguator) - pub(super) fn parse_qpath(&mut self, style: PathStyle) -> PResult<'a, (QSelf, Path)> { + pub(super) fn parse_qpath(&mut self, style: PathStyle) -> PResult<'a, (P<QSelf>, Path)> { let lo = self.prev_token.span; let ty = self.parse_ty()?; @@ -63,7 +64,7 @@ impl<'a> Parser<'a> { path_span = path_lo.to(self.prev_token.span); } else { path_span = self.token.span.to(self.token.span); - path = ast::Path { segments: Vec::new(), span: path_span, tokens: None }; + path = ast::Path { segments: ThinVec::new(), span: path_span, tokens: None }; } // See doc comment for `unmatched_angle_bracket_count`. @@ -77,7 +78,7 @@ impl<'a> Parser<'a> { self.expect(&token::ModSep)?; } - let qself = QSelf { ty, path_span, position: path.segments.len() }; + let qself = P(QSelf { ty, path_span, position: path.segments.len() }); self.parse_path_segments(&mut path.segments, style, None)?; Ok(( @@ -179,7 +180,7 @@ impl<'a> Parser<'a> { } let lo = self.token.span; - let mut segments = Vec::new(); + let mut segments = ThinVec::new(); let mod_sep_ctxt = self.token.span.ctxt(); if self.eat(&token::ModSep) { segments.push(PathSegment::path_root(lo.shrink_to_lo().with_ctxt(mod_sep_ctxt))); @@ -191,7 +192,7 @@ impl<'a> Parser<'a> { pub(super) fn parse_path_segments( &mut self, - segments: &mut Vec<PathSegment>, + segments: &mut ThinVec<PathSegment>, style: PathStyle, ty_generics: Option<&Generics>, ) -> PResult<'a, ()> { @@ -631,7 +632,9 @@ impl<'a> Parser<'a> { /// - A single-segment path. pub(super) fn expr_is_valid_const_arg(&self, expr: &P<rustc_ast::Expr>) -> bool { match &expr.kind { - ast::ExprKind::Block(_, _) | ast::ExprKind::Lit(_) => true, + ast::ExprKind::Block(_, _) + | ast::ExprKind::Lit(_) + | ast::ExprKind::IncludedBytes(..) => true, ast::ExprKind::Unary(ast::UnOp::Neg, expr) => { matches!(expr.kind, ast::ExprKind::Lit(_)) } diff --git a/compiler/rustc_parse/src/parser/stmt.rs b/compiler/rustc_parse/src/parser/stmt.rs index 12753c678..42197e637 100644 --- a/compiler/rustc_parse/src/parser/stmt.rs +++ b/compiler/rustc_parse/src/parser/stmt.rs @@ -10,8 +10,8 @@ use super::{ use crate::errors::{ AssignmentElseNotAllowed, CompoundAssignmentExpressionInLet, ConstLetMutuallyExclusive, DocCommentDoesNotDocumentAnything, ExpectedStatementAfterOuterAttr, InvalidCurlyInLetElse, - InvalidExpressionInLetElse, InvalidVariableDeclaration, InvalidVariableDeclarationSub, - WrapExpressionInParentheses, + InvalidExpressionInLetElse, InvalidIdentiferStartsWithNumber, InvalidVariableDeclaration, + InvalidVariableDeclarationSub, WrapExpressionInParentheses, }; use crate::maybe_whole; @@ -19,7 +19,7 @@ use rustc_ast as ast; use rustc_ast::ptr::P; use rustc_ast::token::{self, Delimiter, TokenKind}; use rustc_ast::util::classify; -use rustc_ast::{AttrStyle, AttrVec, Attribute, LocalKind, MacCall, MacCallStmt, MacStmtStyle}; +use rustc_ast::{AttrStyle, AttrVec, LocalKind, MacCall, MacCallStmt, MacStmtStyle}; use rustc_ast::{Block, BlockCheckMode, Expr, ExprKind, HasAttrs, Local, Stmt}; use rustc_ast::{StmtKind, DUMMY_NODE_ID}; use rustc_errors::{Applicability, DiagnosticBuilder, ErrorGuaranteed, PResult}; @@ -72,14 +72,22 @@ impl<'a> Parser<'a> { Ok(Some(if self.token.is_keyword(kw::Let) { self.parse_local_mk(lo, attrs, capture_semi, force_collect)? - } else if self.is_kw_followed_by_ident(kw::Mut) { - self.recover_stmt_local(lo, attrs, InvalidVariableDeclarationSub::MissingLet)? - } else if self.is_kw_followed_by_ident(kw::Auto) { + } else if self.is_kw_followed_by_ident(kw::Mut) && self.may_recover() { + self.recover_stmt_local_after_let(lo, attrs, InvalidVariableDeclarationSub::MissingLet)? + } else if self.is_kw_followed_by_ident(kw::Auto) && self.may_recover() { self.bump(); // `auto` - self.recover_stmt_local(lo, attrs, InvalidVariableDeclarationSub::UseLetNotAuto)? - } else if self.is_kw_followed_by_ident(sym::var) { + self.recover_stmt_local_after_let( + lo, + attrs, + InvalidVariableDeclarationSub::UseLetNotAuto, + )? + } else if self.is_kw_followed_by_ident(sym::var) && self.may_recover() { self.bump(); // `var` - self.recover_stmt_local(lo, attrs, InvalidVariableDeclarationSub::UseLetNotVar)? + self.recover_stmt_local_after_let( + lo, + attrs, + InvalidVariableDeclarationSub::UseLetNotVar, + )? } else if self.check_path() && !self.token.is_qpath_start() && !self.is_path_start_item() { // We have avoided contextual keywords like `union`, items with `crate` visibility, // or `auto trait` items. We aim to parse an arbitrary path `a::b` but not something @@ -101,7 +109,7 @@ impl<'a> Parser<'a> { self.mk_stmt(lo.to(item.span), StmtKind::Item(P(item))) } else if self.eat(&token::Semi) { // Do not attempt to parse an expression if we're done here. - self.error_outer_attrs(&attrs.take_for_recovery()); + self.error_outer_attrs(attrs); self.mk_stmt(lo, StmtKind::Empty) } else if self.token != token::CloseDelim(Delimiter::Brace) { // Remainder are line-expr stmts. @@ -120,7 +128,7 @@ impl<'a> Parser<'a> { } self.mk_stmt(lo.to(e.span), StmtKind::Expr(e)) } else { - self.error_outer_attrs(&attrs.take_for_recovery()); + self.error_outer_attrs(attrs); return Ok(None); })) } @@ -167,14 +175,13 @@ impl<'a> Parser<'a> { /// Parses a statement macro `mac!(args)` provided a `path` representing `mac`. /// At this point, the `!` token after the path has already been eaten. fn parse_stmt_mac(&mut self, lo: Span, attrs: AttrVec, path: ast::Path) -> PResult<'a, Stmt> { - let args = self.parse_mac_args()?; - let delim = args.delim(); + let args = self.parse_delim_args()?; + let delim = args.delim.to_token(); let hi = self.prev_token.span; let style = match delim { - Some(Delimiter::Brace) => MacStmtStyle::Braces, - Some(_) => MacStmtStyle::NoBraces, - None => unreachable!(), + Delimiter::Brace => MacStmtStyle::Braces, + _ => MacStmtStyle::NoBraces, }; let mac = P(MacCall { path, args, prior_type_ascription: self.last_type_ascription }); @@ -199,8 +206,10 @@ impl<'a> Parser<'a> { /// Error on outer attributes in this context. /// Also error if the previous token was a doc comment. - fn error_outer_attrs(&self, attrs: &[Attribute]) { - if let [.., last] = attrs { + fn error_outer_attrs(&self, attrs: AttrWrapper) { + if !attrs.is_empty() + && let attrs = attrs.take_for_recovery(self.sess) + && let attrs @ [.., last] = &*attrs { if last.is_doc_comment() { self.sess.emit_err(DocCommentDoesNotDocumentAnything { span: last.span, @@ -212,13 +221,21 @@ impl<'a> Parser<'a> { } } - fn recover_stmt_local( + fn recover_stmt_local_after_let( &mut self, lo: Span, attrs: AttrWrapper, subdiagnostic: fn(Span) -> InvalidVariableDeclarationSub, ) -> PResult<'a, Stmt> { - let stmt = self.recover_local_after_let(lo, attrs)?; + let stmt = + self.collect_tokens_trailing_token(attrs, ForceCollect::Yes, |this, attrs| { + let local = this.parse_local(attrs)?; + // FIXME - maybe capture semicolon in recovery? + Ok(( + this.mk_stmt(lo.to(this.prev_token.span), StmtKind::Local(local)), + TrailingToken::None, + )) + })?; self.sess.emit_err(InvalidVariableDeclaration { span: lo, sub: subdiagnostic(lo) }); Ok(stmt) } @@ -242,17 +259,6 @@ impl<'a> Parser<'a> { }) } - fn recover_local_after_let(&mut self, lo: Span, attrs: AttrWrapper) -> PResult<'a, Stmt> { - self.collect_tokens_trailing_token(attrs, ForceCollect::No, |this, attrs| { - let local = this.parse_local(attrs)?; - // FIXME - maybe capture semicolon in recovery? - Ok(( - this.mk_stmt(lo.to(this.prev_token.span), StmtKind::Local(local)), - TrailingToken::None, - )) - }) - } - /// Parses a local variable declaration. fn parse_local(&mut self, attrs: AttrVec) -> PResult<'a, P<Local>> { let lo = self.prev_token.span; @@ -262,6 +268,7 @@ impl<'a> Parser<'a> { self.bump(); } + self.report_invalid_identifier_error()?; let (pat, colon) = self.parse_pat_before_ty(None, RecoverComma::Yes, "`let` bindings")?; let (err, ty) = if colon { @@ -353,6 +360,17 @@ impl<'a> Parser<'a> { Ok(P(ast::Local { ty, pat, kind, id: DUMMY_NODE_ID, span: lo.to(hi), attrs, tokens: None })) } + /// report error for `let 1x = 123` + pub fn report_invalid_identifier_error(&mut self) -> PResult<'a, ()> { + if let token::Literal(lit) = self.token.uninterpolate().kind && + rustc_ast::MetaItemLit::from_token(&self.token).is_none() && + (lit.kind == token::LitKind::Integer || lit.kind == token::LitKind::Float) && + self.look_ahead(1, |t| matches!(t.kind, token::Eq) || matches!(t.kind, token::Colon ) ) { + return Err(self.sess.create_err(InvalidIdentiferStartsWithNumber { span: self.token.span })); + } + Ok(()) + } + fn check_let_else_init_bool_expr(&self, init: &ast::Expr) { if let ast::ExprKind::Binary(op, ..) = init.kind { if op.node.lazy() { @@ -550,9 +568,9 @@ impl<'a> Parser<'a> { }; let mut eat_semi = true; - match stmt.kind { + match &mut stmt.kind { // Expression without semicolon. - StmtKind::Expr(ref mut expr) + StmtKind::Expr(expr) if self.token != token::Eof && classify::expr_requires_semi_to_be_stmt(expr) => { // Just check for errors and recover; do not eat semicolon yet. // `expect_one_of` returns PResult<'a, bool /* recovered */> @@ -598,7 +616,7 @@ impl<'a> Parser<'a> { } } StmtKind::Expr(_) | StmtKind::MacCall(_) => {} - StmtKind::Local(ref mut local) if let Err(e) = self.expect_semi() => { + StmtKind::Local(local) if let Err(e) = self.expect_semi() => { // We might be at the `,` in `let x = foo<bar, baz>;`. Try to recover. match &mut local.kind { LocalKind::Init(expr) | LocalKind::InitElse(expr, _) => { diff --git a/compiler/rustc_parse/src/parser/ty.rs b/compiler/rustc_parse/src/parser/ty.rs index 2a8512acf..b7206b576 100644 --- a/compiler/rustc_parse/src/parser/ty.rs +++ b/compiler/rustc_parse/src/parser/ty.rs @@ -1,9 +1,11 @@ use super::{Parser, PathStyle, TokenType}; +use crate::errors::{FnPtrWithGenerics, FnPtrWithGenericsSugg}; use crate::{maybe_recover_from_interpolated_ty_qpath, maybe_whole}; use rustc_ast::ptr::P; use rustc_ast::token::{self, Delimiter, Token, TokenKind}; +use rustc_ast::util::case::Case; use rustc_ast::{ self as ast, BareFnTy, FnRetTy, GenericBound, GenericBounds, GenericParam, Generics, Lifetime, MacCall, MutTy, Mutability, PolyTraitRef, TraitBoundModifier, TraitObjectSyntax, Ty, TyKind, @@ -267,16 +269,21 @@ impl<'a> Parser<'a> { } else if self.eat_keyword(kw::Underscore) { // A type to be inferred `_` TyKind::Infer - } else if self.check_fn_front_matter(false) { + } else if self.check_fn_front_matter(false, Case::Sensitive) { // Function pointer type - self.parse_ty_bare_fn(lo, Vec::new(), recover_return_sign)? + self.parse_ty_bare_fn(lo, Vec::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` // `for<'lt> Trait1<'lt> + Trait2 + 'a` let lifetime_defs = self.parse_late_bound_lifetime_defs()?; - if self.check_fn_front_matter(false) { - self.parse_ty_bare_fn(lo, lifetime_defs, recover_return_sign)? + if self.check_fn_front_matter(false, Case::Sensitive) { + self.parse_ty_bare_fn( + lo, + lifetime_defs, + Some(self.prev_token.span.shrink_to_lo()), + recover_return_sign, + )? } else { let path = self.parse_path(PathStyle::Type)?; let parse_plus = allow_plus == AllowPlus::Yes && self.check_plus(); @@ -401,7 +408,7 @@ impl<'a> Parser<'a> { .span_suggestions( span.shrink_to_hi(), "add `mut` or `const` here", - ["mut ".to_string(), "const ".to_string()].into_iter(), + ["mut ".to_string(), "const ".to_string()], Applicability::HasPlaceholders, ) .emit(); @@ -518,7 +525,8 @@ impl<'a> Parser<'a> { fn parse_ty_bare_fn( &mut self, lo: Span, - params: Vec<GenericParam>, + mut params: Vec<GenericParam>, + param_insertion_point: Option<Span>, recover_return_sign: RecoverReturnSign, ) -> PResult<'a, TyKind> { let inherited_vis = rustc_ast::Visibility { @@ -528,7 +536,10 @@ impl<'a> Parser<'a> { }; let span_start = self.token.span; let ast::FnHeader { ext, unsafety, constness, asyncness } = - self.parse_fn_front_matter(&inherited_vis)?; + self.parse_fn_front_matter(&inherited_vis, Case::Sensitive)?; + if self.may_recover() && self.token.kind == 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 whole_span = lo.to(self.prev_token.span); if let ast::Const::Yes(span) = constness { @@ -544,6 +555,48 @@ impl<'a> Parser<'a> { Ok(TyKind::BareFn(P(BareFnTy { ext, unsafety, generic_params: params, decl, decl_span }))) } + /// Recover from function pointer types with a generic parameter list (e.g. `fn<'a>(&'a str)`). + fn recover_fn_ptr_with_generics( + &mut self, + lo: Span, + params: &mut Vec<GenericParam>, + param_insertion_point: Option<Span>, + ) -> PResult<'a, ()> { + let generics = self.parse_generics()?; + let arity = generics.params.len(); + + let mut lifetimes: Vec<_> = generics + .params + .into_iter() + .filter(|param| matches!(param.kind, ast::GenericParamKind::Lifetime)) + .collect(); + + let sugg = if !lifetimes.is_empty() { + let snippet = + lifetimes.iter().map(|param| param.ident.as_str()).intersperse(", ").collect(); + + let (left, snippet) = if let Some(span) = param_insertion_point { + (span, if params.is_empty() { snippet } else { format!(", {snippet}") }) + } else { + (lo.shrink_to_lo(), format!("for<{snippet}> ")) + }; + + Some(FnPtrWithGenericsSugg { + left, + snippet, + right: generics.span, + arity, + for_param_list_exists: param_insertion_point.is_some(), + }) + } else { + None + }; + + self.sess.emit_err(FnPtrWithGenerics { span: generics.span, sugg }); + params.append(&mut lifetimes); + 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)) @@ -612,7 +665,7 @@ impl<'a> Parser<'a> { // Macro invocation in type position Ok(TyKind::MacCall(P(MacCall { path, - args: self.parse_mac_args()?, + args: self.parse_delim_args()?, prior_type_ascription: self.last_type_ascription, }))) } else if allow_plus == AllowPlus::Yes && self.check_plus() { |