From e4076e34f8215cff65c4deaff4ba7fbda20d2a7f Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Mon, 29 Jul 2024 21:21:15 -0400 Subject: [PATCH 1/2] Mark Parser::eat/check methods as must_use --- .../rustc_builtin_macros/src/pattern_type.rs | 2 +- compiler/rustc_parse/src/parser/expr.rs | 5 +++-- compiler/rustc_parse/src/parser/generics.rs | 3 ++- compiler/rustc_parse/src/parser/item.rs | 7 ++++--- compiler/rustc_parse/src/parser/mod.rs | 19 +++++++++++++++---- compiler/rustc_parse/src/parser/path.rs | 3 ++- tests/crashes/123809.rs | 2 +- tests/ui/type/pattern_types/missing-is.rs | 8 ++++++++ tests/ui/type/pattern_types/missing-is.stderr | 8 ++++++++ 9 files changed, 44 insertions(+), 13 deletions(-) create mode 100644 tests/ui/type/pattern_types/missing-is.rs create mode 100644 tests/ui/type/pattern_types/missing-is.stderr diff --git a/compiler/rustc_builtin_macros/src/pattern_type.rs b/compiler/rustc_builtin_macros/src/pattern_type.rs index 87187125541..869d203f68e 100644 --- a/compiler/rustc_builtin_macros/src/pattern_type.rs +++ b/compiler/rustc_builtin_macros/src/pattern_type.rs @@ -24,7 +24,7 @@ fn parse_pat_ty<'a>(cx: &mut ExtCtxt<'a>, stream: TokenStream) -> PResult<'a, (P let mut parser = cx.new_parser_from_tts(stream); let ty = parser.parse_ty()?; - parser.eat_keyword(sym::is); + parser.expect_keyword(sym::is)?; let pat = parser.parse_pat_no_top_alt(None, None)?; Ok((ty, pat)) diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index a242dc5cd58..a4d9d97045d 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -3153,7 +3153,8 @@ impl<'a> Parser<'a> { if !require_comma { arm_body = Some(expr); - this.eat(&token::Comma); + // Eat a comma if it exists, though. + let _ = this.eat(&token::Comma); Ok(Recovered::No) } else if let Some((span, guar)) = this.parse_arm_body_missing_braces(&expr, arrow_span) @@ -3654,7 +3655,7 @@ impl<'a> Parser<'a> { fields.push(f); } self.recover_stmt_(SemiColonMode::Comma, BlockMode::Ignore); - self.eat(&token::Comma); + let _ = self.eat(&token::Comma); } } } diff --git a/compiler/rustc_parse/src/parser/generics.rs b/compiler/rustc_parse/src/parser/generics.rs index a67e3d05551..9124c15707d 100644 --- a/compiler/rustc_parse/src/parser/generics.rs +++ b/compiler/rustc_parse/src/parser/generics.rs @@ -178,7 +178,8 @@ impl<'a> Parser<'a> { span: this.prev_token.span, }); - this.eat(&token::Comma); + // Eat a trailing comma, if it exists. + let _ = this.eat(&token::Comma); } let param = if this.check_lifetime() { diff --git a/compiler/rustc_parse/src/parser/item.rs b/compiler/rustc_parse/src/parser/item.rs index 68da0554945..baa5eb2df63 100644 --- a/compiler/rustc_parse/src/parser/item.rs +++ b/compiler/rustc_parse/src/parser/item.rs @@ -1192,13 +1192,14 @@ impl<'a> Parser<'a> { mut safety: Safety, ) -> PResult<'a, ItemInfo> { let abi = self.parse_abi(); // ABI? + // FIXME: This recovery should be tested better. if safety == Safety::Default && self.token.is_keyword(kw::Unsafe) && self.look_ahead(1, |t| t.kind == token::OpenDelim(Delimiter::Brace)) { self.expect(&token::OpenDelim(Delimiter::Brace)).unwrap_err().emit(); safety = Safety::Unsafe(self.token.span); - self.eat_keyword(kw::Unsafe); + let _ = self.eat_keyword(kw::Unsafe); } let module = ast::ForeignMod { safety, @@ -1759,7 +1760,7 @@ impl<'a> Parser<'a> { } } } - self.eat(&token::CloseDelim(Delimiter::Brace)); + self.expect(&token::CloseDelim(Delimiter::Brace))?; } else { let token_str = super::token_descr(&self.token); let where_str = if parsed_where { "" } else { "`where`, or " }; @@ -1902,7 +1903,7 @@ impl<'a> Parser<'a> { if let Some(_guar) = guar { // Handle a case like `Vec>,` where we can continue parsing fields // after the comma - self.eat(&token::Comma); + let _ = self.eat(&token::Comma); // `check_trailing_angle_brackets` already emitted a nicer error, as // proven by the presence of `_guar`. We can continue parsing. diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs index 26ee5bfdee4..e01f605722b 100644 --- a/compiler/rustc_parse/src/parser/mod.rs +++ b/compiler/rustc_parse/src/parser/mod.rs @@ -547,6 +547,7 @@ impl<'a> Parser<'a> { } #[inline] + #[must_use] fn check_noexpect(&self, tok: &TokenKind) -> bool { self.token == *tok } @@ -556,6 +557,7 @@ impl<'a> Parser<'a> { /// the main purpose of this function is to reduce the cluttering of the suggestions list /// which using the normal eat method could introduce in some cases. #[inline] + #[must_use] fn eat_noexpect(&mut self, tok: &TokenKind) -> bool { let is_present = self.check_noexpect(tok); if is_present { @@ -566,6 +568,7 @@ impl<'a> Parser<'a> { /// Consumes a token 'tok' if it exists. Returns whether the given token was present. #[inline] + #[must_use] pub fn eat(&mut self, tok: &TokenKind) -> bool { let is_present = self.check(tok); if is_present { @@ -577,12 +580,14 @@ impl<'a> Parser<'a> { /// If the next token is the given keyword, returns `true` without eating it. /// An expectation is also added for diagnostics purposes. #[inline] + #[must_use] fn check_keyword(&mut self, kw: Symbol) -> bool { self.expected_tokens.push(TokenType::Keyword(kw)); self.token.is_keyword(kw) } #[inline] + #[must_use] fn check_keyword_case(&mut self, kw: Symbol, case: Case) -> bool { if self.check_keyword(kw) { return true; @@ -602,6 +607,7 @@ impl<'a> Parser<'a> { /// Otherwise, returns `false`. An expectation is also added for diagnostics purposes. // Public for rustc_builtin_macros and rustfmt usage. #[inline] + #[must_use] pub fn eat_keyword(&mut self, kw: Symbol) -> bool { if self.check_keyword(kw) { self.bump(); @@ -615,6 +621,7 @@ impl<'a> Parser<'a> { /// If the case differs (and is ignored) an error is issued. /// This is useful for recovery. #[inline] + #[must_use] fn eat_keyword_case(&mut self, kw: Symbol, case: Case) -> bool { if self.eat_keyword(kw) { return true; @@ -636,6 +643,7 @@ impl<'a> Parser<'a> { /// Otherwise, returns `false`. No expectation is added. // Public for rustc_builtin_macros usage. #[inline] + #[must_use] pub fn eat_keyword_noexpect(&mut self, kw: Symbol) -> bool { if self.token.is_keyword(kw) { self.bump(); @@ -648,7 +656,7 @@ impl<'a> Parser<'a> { /// If the given word is not a keyword, signals an error. /// If the next token is not the given word, signals an error. /// Otherwise, eats it. - fn expect_keyword(&mut self, kw: Symbol) -> PResult<'a, ()> { + pub fn expect_keyword(&mut self, kw: Symbol) -> PResult<'a, ()> { if !self.eat_keyword(kw) { self.unexpected() } else { Ok(()) } } @@ -1025,8 +1033,11 @@ impl<'a> Parser<'a> { f: impl FnMut(&mut Parser<'a>) -> PResult<'a, T>, ) -> PResult<'a, (ThinVec, Trailing)> { let (val, trailing, recovered) = self.parse_seq_to_before_end(ket, sep, f)?; - if matches!(recovered, Recovered::No) { - self.eat(ket); + if matches!(recovered, Recovered::No) && !self.eat(ket) { + self.dcx().span_delayed_bug( + self.token.span, + "recovered but `parse_seq_to_before_end` did not give us the ket token", + ); } Ok((val, trailing)) } @@ -1250,7 +1261,7 @@ impl<'a> Parser<'a> { if pat { self.psess.gated_spans.gate(sym::inline_const_pat, span); } - self.eat_keyword(kw::Const); + self.expect_keyword(kw::Const)?; let (attrs, blk) = self.parse_inner_attrs_and_block()?; let anon_const = AnonConst { id: DUMMY_NODE_ID, diff --git a/compiler/rustc_parse/src/parser/path.rs b/compiler/rustc_parse/src/parser/path.rs index c5111226d37..70d2c98d4f1 100644 --- a/compiler/rustc_parse/src/parser/path.rs +++ b/compiler/rustc_parse/src/parser/path.rs @@ -313,7 +313,8 @@ impl<'a> Parser<'a> { } // Generic arguments are found - `<`, `(`, `::<` or `::(`. - self.eat(&token::PathSep); + // First, eat `::` if it exists. + let _ = self.eat(&token::PathSep); let lo = self.token.span; let args = if self.eat_lt() { // `<'a, T, A = U>` diff --git a/tests/crashes/123809.rs b/tests/crashes/123809.rs index c7a633aed01..75abe6dc0cd 100644 --- a/tests/crashes/123809.rs +++ b/tests/crashes/123809.rs @@ -1,4 +1,4 @@ //@ known-bug: #123809 -type Positive = std::pat::pattern_type!(std::pat:: is 0..); +type Positive = std::pat::pattern_type!(std::pat is 0..); pub fn main() {} diff --git a/tests/ui/type/pattern_types/missing-is.rs b/tests/ui/type/pattern_types/missing-is.rs new file mode 100644 index 00000000000..2fbcc1908ef --- /dev/null +++ b/tests/ui/type/pattern_types/missing-is.rs @@ -0,0 +1,8 @@ +#![feature(core_pattern_type, core_pattern_types)] + +use std::pat::pattern_type; + +fn main() { + let x: pattern_type!(i32 0..1); + //~^ ERROR expected one of `!`, `(`, `+`, `::`, `<`, or `is`, found `0` +} diff --git a/tests/ui/type/pattern_types/missing-is.stderr b/tests/ui/type/pattern_types/missing-is.stderr new file mode 100644 index 00000000000..8ed654fe907 --- /dev/null +++ b/tests/ui/type/pattern_types/missing-is.stderr @@ -0,0 +1,8 @@ +error: expected one of `!`, `(`, `+`, `::`, `<`, or `is`, found `0` + --> $DIR/missing-is.rs:6:30 + | +LL | let x: pattern_type!(i32 0..1); + | ^ expected one of `!`, `(`, `+`, `::`, `<`, or `is` + +error: aborting due to 1 previous error + From 4776ac0f885044685c6f6127632f42522a88c05d Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Tue, 30 Jul 2024 10:10:36 -0400 Subject: [PATCH 2/2] Suppress must_use on eat calls in rustfmt --- src/tools/rustfmt/src/parse/macros/lazy_static.rs | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/src/tools/rustfmt/src/parse/macros/lazy_static.rs b/src/tools/rustfmt/src/parse/macros/lazy_static.rs index 7baac247e22..b6de5f8691c 100644 --- a/src/tools/rustfmt/src/parse/macros/lazy_static.rs +++ b/src/tools/rustfmt/src/parse/macros/lazy_static.rs @@ -33,15 +33,17 @@ pub(crate) fn parse_lazy_static( } while parser.token.kind != TokenKind::Eof { // Parse a `lazy_static!` item. + // FIXME: These `eat_*` calls should be converted to `parse_or` to avoid + // silently formatting malformed lazy-statics. let vis = parse_or!(parse_visibility, rustc_parse::parser::FollowedByType::No); - parser.eat_keyword(kw::Static); - parser.eat_keyword(kw::Ref); + let _ = parser.eat_keyword(kw::Static); + let _ = parser.eat_keyword(kw::Ref); let id = parse_or!(parse_ident); - parser.eat(&TokenKind::Colon); + let _ = parser.eat(&TokenKind::Colon); let ty = parse_or!(parse_ty); - parser.eat(&TokenKind::Eq); + let _ = parser.eat(&TokenKind::Eq); let expr = parse_or!(parse_expr); - parser.eat(&TokenKind::Semi); + let _ = parser.eat(&TokenKind::Semi); result.push((vis, id, ty, expr)); }