From de3a0bdf0503b22a8e4507c7b2d4cb84c335d272 Mon Sep 17 00:00:00 2001 From: unknown Date: Mon, 23 Nov 2020 18:53:47 -0300 Subject: [PATCH] Fixes #79357 unstable or-pat suggestions --- compiler/rustc_parse/src/parser/pat.rs | 33 ++++++++++++------- ...92-tuple-destructure-missing-parens.stderr | 33 ++----------------- 2 files changed, 25 insertions(+), 41 deletions(-) diff --git a/compiler/rustc_parse/src/parser/pat.rs b/compiler/rustc_parse/src/parser/pat.rs index ee9a6dca5ad..b62c7373800 100644 --- a/compiler/rustc_parse/src/parser/pat.rs +++ b/compiler/rustc_parse/src/parser/pat.rs @@ -18,7 +18,7 @@ pub(super) const PARAM_EXPECTED: Expected = Some("parameter name"); const WHILE_PARSING_OR_MSG: &str = "while parsing this or-pattern starting here"; /// Whether or not an or-pattern should be gated when occurring in the current context. -#[derive(PartialEq)] +#[derive(PartialEq, Clone, Copy)] pub(super) enum GateOr { Yes, No, @@ -94,7 +94,7 @@ impl<'a> Parser<'a> { ) -> PResult<'a, P> { // Parse the first pattern (`p_0`). let first_pat = self.parse_pat(expected)?; - self.maybe_recover_unexpected_comma(first_pat.span, rc)?; + self.maybe_recover_unexpected_comma(first_pat.span, rc, gate_or)?; // If the next token is not a `|`, // this is not an or-pattern and we should exit here. @@ -110,7 +110,7 @@ impl<'a> Parser<'a> { err.span_label(lo, WHILE_PARSING_OR_MSG); err })?; - self.maybe_recover_unexpected_comma(pat.span, rc)?; + self.maybe_recover_unexpected_comma(pat.span, rc, gate_or)?; pats.push(pat); } let or_pattern_span = lo.to(self.prev_token.span); @@ -190,7 +190,12 @@ impl<'a> Parser<'a> { /// Some special error handling for the "top-level" patterns in a match arm, /// `for` loop, `let`, &c. (in contrast to subpatterns within such). - fn maybe_recover_unexpected_comma(&mut self, lo: Span, rc: RecoverComma) -> PResult<'a, ()> { + fn maybe_recover_unexpected_comma( + &mut self, + lo: Span, + rc: RecoverComma, + gate_or: GateOr, + ) -> PResult<'a, ()> { if rc == RecoverComma::No || self.token != token::Comma { return Ok(()); } @@ -209,18 +214,24 @@ impl<'a> Parser<'a> { let seq_span = lo.to(self.prev_token.span); let mut err = self.struct_span_err(comma_span, "unexpected `,` in pattern"); if let Ok(seq_snippet) = self.span_to_snippet(seq_span) { + const MSG: &str = "try adding parentheses to match on a tuple..."; + + let or_suggestion = + gate_or == GateOr::No || !self.sess.gated_spans.is_ungated(sym::or_patterns); err.span_suggestion( seq_span, - "try adding parentheses to match on a tuple...", + if or_suggestion { MSG } else { MSG.trim_end_matches('.') }, format!("({})", seq_snippet), Applicability::MachineApplicable, - ) - .span_suggestion( - seq_span, - "...or a vertical bar to match on multiple alternatives", - seq_snippet.replace(",", " |"), - Applicability::MachineApplicable, ); + if or_suggestion { + err.span_suggestion( + seq_span, + "...or a vertical bar to match on multiple alternatives", + seq_snippet.replace(",", " |"), + Applicability::MachineApplicable, + ); + } } Err(err) } diff --git a/src/test/ui/did_you_mean/issue-48492-tuple-destructure-missing-parens.stderr b/src/test/ui/did_you_mean/issue-48492-tuple-destructure-missing-parens.stderr index d05d6d120b0..26c24d7432c 100644 --- a/src/test/ui/did_you_mean/issue-48492-tuple-destructure-missing-parens.stderr +++ b/src/test/ui/did_you_mean/issue-48492-tuple-destructure-missing-parens.stderr @@ -47,46 +47,19 @@ error: unexpected `,` in pattern --> $DIR/issue-48492-tuple-destructure-missing-parens.rs:67:10 | LL | for x, _barr_body in women.iter().map(|woman| woman.allosomes.clone()) { - | ^ - | -help: try adding parentheses to match on a tuple... - | -LL | for (x, _barr_body) in women.iter().map(|woman| woman.allosomes.clone()) { - | ^^^^^^^^^^^^^^^ -help: ...or a vertical bar to match on multiple alternatives - | -LL | for x | _barr_body in women.iter().map(|woman| woman.allosomes.clone()) { - | ^^^^^^^^^^^^^^ + | -^----------- help: try adding parentheses to match on a tuple: `(x, _barr_body)` error: unexpected `,` in pattern --> $DIR/issue-48492-tuple-destructure-missing-parens.rs:75:10 | LL | for x, y @ Allosome::Y(_) in men.iter().map(|man| man.allosomes.clone()) { - | ^ - | -help: try adding parentheses to match on a tuple... - | -LL | for (x, y @ Allosome::Y(_)) in men.iter().map(|man| man.allosomes.clone()) { - | ^^^^^^^^^^^^^^^^^^^^^^^ -help: ...or a vertical bar to match on multiple alternatives - | -LL | for x | y @ Allosome::Y(_) in men.iter().map(|man| man.allosomes.clone()) { - | ^^^^^^^^^^^^^^^^^^^^^^ + | -^------------------- help: try adding parentheses to match on a tuple: `(x, y @ Allosome::Y(_))` error: unexpected `,` in pattern --> $DIR/issue-48492-tuple-destructure-missing-parens.rs:84:14 | LL | let women, men: (Vec, Vec) = genomes.iter().cloned() - | ^ - | -help: try adding parentheses to match on a tuple... - | -LL | let (women, men): (Vec, Vec) = genomes.iter().cloned() - | ^^^^^^^^^^^^ -help: ...or a vertical bar to match on multiple alternatives - | -LL | let women | men: (Vec, Vec) = genomes.iter().cloned() - | ^^^^^^^^^^^ + | -----^---- help: try adding parentheses to match on a tuple: `(women, men)` error: aborting due to 6 previous errors