diff options
Diffstat (limited to 'compiler/rustc_parse/src/parser/expr.rs')
| -rw-r--r-- | compiler/rustc_parse/src/parser/expr.rs | 165 |
1 files changed, 94 insertions, 71 deletions
diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index 89f28777bff..e1a5e17004f 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -34,7 +34,7 @@ use rustc_session::lint::builtin::BREAK_WITH_LABEL_AND_LOOP; use rustc_session::lint::BuiltinLintDiagnostics; use rustc_span::source_map::{self, Spanned}; use rustc_span::symbol::{kw, sym, Ident, Symbol}; -use rustc_span::{BytePos, Pos, Span}; +use rustc_span::{BytePos, ErrorGuaranteed, Pos, Span}; use thin_vec::{thin_vec, ThinVec}; /// Possibly accepts an `token::Interpolated` expression (a pre-parsed expression @@ -131,9 +131,9 @@ impl<'a> Parser<'a> { if self.may_recover() && self.look_ahead(1, |t| t == &token::Comma) => { // Special-case handling of `foo(_, _, _)` - err.emit(); + let guar = err.emit(); self.bump(); - Ok(self.mk_expr(self.prev_token.span, ExprKind::Err)) + Ok(self.mk_expr(self.prev_token.span, ExprKind::Err(guar))) } _ => Err(err), }, @@ -667,8 +667,8 @@ impl<'a> Parser<'a> { let (span, _) = self.parse_expr_prefix_common(box_kw)?; let inner_span = span.with_lo(box_kw.hi()); let code = self.sess.source_map().span_to_snippet(inner_span).unwrap(); - self.dcx().emit_err(errors::BoxSyntaxRemoved { span: span, code: code.trim() }); - Ok((span, ExprKind::Err)) + let guar = self.dcx().emit_err(errors::BoxSyntaxRemoved { span: span, code: code.trim() }); + Ok((span, ExprKind::Err(guar))) } fn is_mistaken_not_ident_negation(&self) -> bool { @@ -860,7 +860,7 @@ impl<'a> Parser<'a> { ExprKind::MethodCall(_) => "a method call", ExprKind::Call(_, _) => "a function call", ExprKind::Await(_, _) => "`.await`", - ExprKind::Err => return Ok(with_postfix), + ExprKind::Err(_) => return Ok(with_postfix), _ => unreachable!("parse_dot_or_call_expr_with_ shouldn't produce this"), } ); @@ -1315,7 +1315,7 @@ impl<'a> Parser<'a> { let fields: Vec<_> = fields.into_iter().filter(|field| !field.is_shorthand).collect(); - if !fields.is_empty() && + let guar = if !fields.is_empty() && // `token.kind` should not be compared here. // This is because the `snapshot.token.kind` is treated as the same as // that of the open delim in `TokenTreesReader::parse_token_tree`, even @@ -1338,11 +1338,11 @@ impl<'a> Parser<'a> { .collect(), }, }) - .emit(); + .emit() } else { - err.emit(); - } - Ok(self.mk_expr_err(span)) + err.emit() + }; + Ok(self.mk_expr_err(span, guar)) } Ok(_) => Err(err), Err(err2) => { @@ -1684,13 +1684,13 @@ impl<'a> Parser<'a> { && (self.check_noexpect(&TokenKind::Comma) || self.check_noexpect(&TokenKind::Gt)) { // We're probably inside of a `Path<'a>` that needs a turbofish - self.dcx().emit_err(errors::UnexpectedTokenAfterLabel { + let guar = self.dcx().emit_err(errors::UnexpectedTokenAfterLabel { span: self.token.span, remove_label: None, enclose_in_block: None, }); consume_colon = false; - Ok(self.mk_expr_err(lo)) + Ok(self.mk_expr_err(lo, guar)) } else { let mut err = errors::UnexpectedTokenAfterLabel { span: self.token.span, @@ -2039,7 +2039,7 @@ impl<'a> Parser<'a> { ) -> PResult<'a, L> { if let token::Interpolated(nt) = &self.token.kind && let token::NtExpr(e) | token::NtLiteral(e) = &nt.0 - && matches!(e.kind, ExprKind::Err) + && matches!(e.kind, ExprKind::Err(_)) { let mut err = self .dcx() @@ -2207,7 +2207,7 @@ impl<'a> Parser<'a> { let mut snapshot = self.create_snapshot_for_diagnostic(); match snapshot.parse_expr_array_or_repeat(Delimiter::Brace) { Ok(arr) => { - self.dcx().emit_err(errors::ArrayBracketsInsteadOfSpaces { + let guar = self.dcx().emit_err(errors::ArrayBracketsInsteadOfSpaces { span: arr.span, sub: errors::ArrayBracketsInsteadOfSpacesSugg { left: lo, @@ -2216,7 +2216,7 @@ impl<'a> Parser<'a> { }); self.restore_snapshot(snapshot); - Some(self.mk_expr_err(arr.span)) + Some(self.mk_expr_err(arr.span, guar)) } Err(e) => { e.cancel(); @@ -2370,7 +2370,10 @@ impl<'a> Parser<'a> { // It is likely that the closure body is a block but where the // braces have been removed. We will recover and eat the next // statements later in the parsing process. - body = self.mk_expr_err(body.span); + body = self.mk_expr_err( + body.span, + self.dcx().span_delayed_bug(body.span, "recovered a closure body as a block"), + ); } let body_span = body.span; @@ -2485,7 +2488,7 @@ impl<'a> Parser<'a> { ExprKind::Binary(Spanned { span: binop_span, .. }, _, right) if let ExprKind::Block(_, None) = right.kind => { - this.dcx().emit_err(errors::IfExpressionMissingThenBlock { + let guar = this.dcx().emit_err(errors::IfExpressionMissingThenBlock { if_span: lo, missing_then_block_sub: errors::IfExpressionMissingThenBlockSub::UnfinishedCondition( @@ -2493,14 +2496,14 @@ impl<'a> Parser<'a> { ), let_else_sub: None, }); - std::mem::replace(right, this.mk_expr_err(binop_span.shrink_to_hi())) + std::mem::replace(right, this.mk_expr_err(binop_span.shrink_to_hi(), guar)) } ExprKind::Block(_, None) => { - this.dcx().emit_err(errors::IfExpressionMissingCondition { + let guar = this.dcx().emit_err(errors::IfExpressionMissingCondition { if_span: lo.with_neighbor(cond.span).shrink_to_hi(), block_span: self.sess.source_map().start_point(cond_span), }); - std::mem::replace(&mut cond, this.mk_expr_err(cond_span.shrink_to_hi())) + std::mem::replace(&mut cond, this.mk_expr_err(cond_span.shrink_to_hi(), guar)) } _ => { return None; @@ -2520,14 +2523,14 @@ impl<'a> Parser<'a> { let let_else_sub = matches!(cond.kind, ExprKind::Let(..)) .then(|| errors::IfExpressionLetSomeSub { if_span: lo.until(cond_span) }); - self.dcx().emit_err(errors::IfExpressionMissingThenBlock { + let guar = self.dcx().emit_err(errors::IfExpressionMissingThenBlock { if_span: lo, missing_then_block_sub: errors::IfExpressionMissingThenBlockSub::AddThenBlock( cond_span.shrink_to_hi(), ), let_else_sub, }); - self.mk_block_err(cond_span.shrink_to_hi()) + self.mk_block_err(cond_span.shrink_to_hi(), guar) } } else { let attrs = self.parse_outer_attributes()?; // For recovery. @@ -2797,9 +2800,10 @@ impl<'a> Parser<'a> { && !matches!(self.token.kind, token::OpenDelim(Delimiter::Brace)) && self.may_recover() { - self.dcx() + let guar = self + .dcx() .emit_err(errors::MissingExpressionInForLoop { span: expr.span.shrink_to_lo() }); - let err_expr = self.mk_expr(expr.span, ExprKind::Err); + let err_expr = self.mk_expr(expr.span, ExprKind::Err(guar)); let block = self.mk_block(thin_vec![], BlockCheckMode::Default, self.prev_token.span); return Ok(self.mk_expr( lo.to(self.prev_token.span), @@ -2924,7 +2928,7 @@ impl<'a> Parser<'a> { attrs: Default::default(), pat: self.mk_pat(span, ast::PatKind::Err(guar)), guard: None, - body: Some(self.mk_expr_err(span)), + body: Some(self.mk_expr_err(span, guar)), span, id: DUMMY_NODE_ID, is_placeholder: false, @@ -2959,7 +2963,7 @@ impl<'a> Parser<'a> { let err = |this: &Parser<'_>, stmts: Vec<ast::Stmt>| { let span = stmts[0].span.to(stmts[stmts.len() - 1].span); - this.dcx().emit_err(errors::MatchArmBodyWithoutBraces { + let guar = this.dcx().emit_err(errors::MatchArmBodyWithoutBraces { statements: span, arrow: arrow_span, num_statements: stmts.len(), @@ -2972,7 +2976,7 @@ impl<'a> Parser<'a> { errors::MatchArmBodyWithoutBracesSugg::UseComma { semicolon: semi_sp } }, }); - this.mk_expr_err(span) + this.mk_expr_err(span, guar) }; // We might have either a `,` -> `;` typo, or a block without braces. We need // a more subtle parsing strategy. @@ -3433,14 +3437,20 @@ impl<'a> Parser<'a> { pth: ast::Path, recover: bool, close_delim: Delimiter, - ) -> PResult<'a, (ThinVec<ExprField>, ast::StructRest, bool)> { + ) -> PResult< + 'a, + ( + ThinVec<ExprField>, + ast::StructRest, + Option<ErrorGuaranteed>, /* async blocks are forbidden in Rust 2015 */ + ), + > { let mut fields = ThinVec::new(); let mut base = ast::StructRest::None; - let mut recover_async = false; + let mut recovered_async = None; let in_if_guard = self.restrictions.contains(Restrictions::IN_IF_GUARD); - let mut async_block_err = |e: &mut DiagnosticBuilder<'_>, span: Span| { - recover_async = true; + let async_block_err = |e: &mut DiagnosticBuilder<'_>, span: Span| { errors::AsyncBlockIn2015 { span }.add_to_diagnostic(e); errors::HelpUseLatestEdition::new().add_to_diagnostic(e); }; @@ -3465,9 +3475,34 @@ impl<'a> Parser<'a> { break; } - let recovery_field = self.find_struct_error_after_field_looking_code(); + // Peek the field's ident before parsing its expr in order to emit better diagnostics. + let peek = self + .token + .ident() + .filter(|(ident, is_raw)| { + (!ident.is_reserved() || matches!(is_raw, IdentIsRaw::Yes)) + && self.look_ahead(1, |tok| *tok == token::Colon) + }) + .map(|(ident, _)| ident); + + // We still want a field even if its expr didn't parse. + let field_ident = |this: &Self, guar: ErrorGuaranteed| { + peek.map(|ident| { + let span = ident.span; + ExprField { + ident, + span, + expr: this.mk_expr_err(span, guar), + is_shorthand: false, + attrs: AttrVec::new(), + id: DUMMY_NODE_ID, + is_placeholder: false, + } + }) + }; + let parsed_field = match self.parse_expr_field() { - Ok(f) => Some(f), + Ok(f) => Ok(f), Err(mut e) => { if pth == kw::Async { async_block_err(&mut e, pth.span); @@ -3499,7 +3534,10 @@ impl<'a> Parser<'a> { return Err(e); } - e.emit(); + let guar = e.emit(); + if pth == kw::Async { + recovered_async = Some(guar); + } // If the next token is a comma, then try to parse // what comes next as additional fields, rather than @@ -3511,18 +3549,20 @@ impl<'a> Parser<'a> { } } - None + Err(guar) } }; - let is_shorthand = parsed_field.as_ref().is_some_and(|f| f.is_shorthand); + let is_shorthand = parsed_field.as_ref().is_ok_and(|f| f.is_shorthand); // A shorthand field can be turned into a full field with `:`. // We should point this out. self.check_or_expected(!is_shorthand, TokenType::Token(token::Colon)); match self.expect_one_of(&[token::Comma], &[token::CloseDelim(close_delim)]) { Ok(_) => { - if let Some(f) = parsed_field.or(recovery_field) { + if let Some(f) = + parsed_field.or_else(|guar| field_ident(self, guar).ok_or(guar)).ok() + { // Only include the field if there's no parse error for the field name. fields.push(f); } @@ -3532,8 +3572,7 @@ impl<'a> Parser<'a> { async_block_err(&mut e, pth.span); } else { e.span_label(pth.span, "while parsing this struct"); - if let Some(f) = recovery_field { - fields.push(f); + if peek.is_some() { e.span_suggestion( self.prev_token.span.shrink_to_hi(), "try adding a comma", @@ -3545,13 +3584,18 @@ impl<'a> Parser<'a> { if !recover { return Err(e); } - e.emit(); + let guar = e.emit(); + if pth == kw::Async { + recovered_async = Some(guar); + } else if let Some(f) = field_ident(self, guar) { + fields.push(f); + } self.recover_stmt_(SemiColonMode::Comma, BlockMode::Ignore); self.eat(&token::Comma); } } } - Ok((fields, base, recover_async)) + Ok((fields, base, recovered_async)) } /// Precondition: already parsed the '{'. @@ -3562,39 +3606,18 @@ impl<'a> Parser<'a> { recover: bool, ) -> PResult<'a, P<Expr>> { let lo = pth.span; - let (fields, base, recover_async) = + let (fields, base, recovered_async) = self.parse_struct_fields(pth.clone(), recover, Delimiter::Brace)?; let span = lo.to(self.token.span); self.expect(&token::CloseDelim(Delimiter::Brace))?; - let expr = if recover_async { - ExprKind::Err + let expr = if let Some(guar) = recovered_async { + ExprKind::Err(guar) } else { ExprKind::Struct(P(ast::StructExpr { qself, path: pth, fields, rest: base })) }; Ok(self.mk_expr(span, expr)) } - /// Use in case of error after field-looking code: `S { foo: () with a }`. - fn find_struct_error_after_field_looking_code(&self) -> Option<ExprField> { - match self.token.ident() { - Some((ident, is_raw)) - if (matches!(is_raw, IdentIsRaw::Yes) || !ident.is_reserved()) - && self.look_ahead(1, |t| *t == token::Colon) => - { - Some(ast::ExprField { - ident, - span: self.token.span, - expr: self.mk_expr_err(self.token.span), - is_shorthand: false, - attrs: AttrVec::new(), - id: DUMMY_NODE_ID, - is_placeholder: false, - }) - } - _ => None, - } - } - fn recover_struct_comma_after_dotdot(&mut self, span: Span) { if self.token != token::Comma { return; @@ -3718,8 +3741,8 @@ impl<'a> Parser<'a> { limits: RangeLimits, ) -> ExprKind { if end.is_none() && limits == RangeLimits::Closed { - self.inclusive_range_with_incorrect_end(); - ExprKind::Err + let guar = self.inclusive_range_with_incorrect_end(); + ExprKind::Err(guar) } else { ExprKind::Range(start, end, limits) } @@ -3756,8 +3779,8 @@ impl<'a> Parser<'a> { self.mk_expr_with_attrs(span, kind, AttrVec::new()) } - pub(super) fn mk_expr_err(&self, span: Span) -> P<Expr> { - self.mk_expr(span, ExprKind::Err) + pub(super) fn mk_expr_err(&self, span: Span, guar: ErrorGuaranteed) -> P<Expr> { + self.mk_expr(span, ExprKind::Err(guar)) } /// Create expression span ensuring the span of the parent node @@ -3949,7 +3972,7 @@ impl MutVisitor for CondChecker<'_> { | ExprKind::Become(_) | ExprKind::IncludedBytes(_) | ExprKind::FormatArgs(_) - | ExprKind::Err + | ExprKind::Err(_) | ExprKind::Dummy => { // These would forbid any let expressions they contain already. } |