diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index 3225a309a31..17d1e200b41 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -3168,7 +3168,7 @@ impl<'a> Parser<'a> { limits: RangeLimits, ) -> ExprKind { if end.is_none() && limits == RangeLimits::Closed { - self.inclusive_range_with_incorrect_end(self.prev_token.span); + self.inclusive_range_with_incorrect_end(); ExprKind::Err } else { ExprKind::Range(start, end, limits) diff --git a/compiler/rustc_parse/src/parser/pat.rs b/compiler/rustc_parse/src/parser/pat.rs index e5411538eea..9cde0026920 100644 --- a/compiler/rustc_parse/src/parser/pat.rs +++ b/compiler/rustc_parse/src/parser/pat.rs @@ -746,32 +746,38 @@ impl<'a> Parser<'a> { // Parsing e.g. `X..`. if let RangeEnd::Included(_) = re.node { // FIXME(Centril): Consider semantic errors instead in `ast_validation`. - self.inclusive_range_with_incorrect_end(re.span); + self.inclusive_range_with_incorrect_end(); } None }; Ok(PatKind::Range(Some(begin), end, re)) } - pub(super) fn inclusive_range_with_incorrect_end(&mut self, span: Span) { + pub(super) fn inclusive_range_with_incorrect_end(&mut self) { let tok = &self.token; - + let span = self.prev_token.span; // If the user typed "..==" instead of "..=", we want to give them // a specific error message telling them to use "..=". + // If they typed "..=>", suggest they use ".. =>". // Otherwise, we assume that they meant to type a half open exclusive // range and give them an error telling them to do that instead. - if matches!(tok.kind, token::Eq) && tok.span.lo() == span.hi() { - let span_with_eq = span.to(tok.span); + let no_space = tok.span.lo() == span.hi(); + match tok.kind { + token::Eq if no_space => { + let span_with_eq = span.to(tok.span); - // Ensure the user doesn't receive unhelpful unexpected token errors - self.bump(); - if self.is_pat_range_end_start(0) { - let _ = self.parse_pat_range_end().map_err(|e| e.cancel()); + // Ensure the user doesn't receive unhelpful unexpected token errors + self.bump(); + if self.is_pat_range_end_start(0) { + let _ = self.parse_pat_range_end().map_err(|e| e.cancel()); + } + + self.error_inclusive_range_with_extra_equals(span_with_eq); } - - self.error_inclusive_range_with_extra_equals(span_with_eq); - } else { - self.error_inclusive_range_with_no_end(span); + token::Gt if no_space => { + self.error_inclusive_range_match_arrow(span); + } + _ => self.error_inclusive_range_with_no_end(span), } } @@ -782,6 +788,18 @@ impl<'a> Parser<'a> { .emit(); } + fn error_inclusive_range_match_arrow(&self, span: Span) { + let without_eq = span.with_hi(span.hi() - rustc_span::BytePos(1)); + self.struct_span_err(span, "unexpected `=>` after open range") + .span_suggestion_verbose( + without_eq.shrink_to_hi(), + "add a space between the pattern and `=>`", + " ", + Applicability::MachineApplicable, + ) + .emit(); + } + fn error_inclusive_range_with_no_end(&self, span: Span) { struct_span_err!(self.sess.span_diagnostic, span, E0586, "inclusive range with no end") .span_suggestion_short(span, "use `..` instead", "..", Applicability::MachineApplicable) diff --git a/tests/ui/half-open-range-patterns/half-open-range-pats-inclusive-match-arrow.rs b/tests/ui/half-open-range-patterns/half-open-range-pats-inclusive-match-arrow.rs new file mode 100644 index 00000000000..7ba2b6d857c --- /dev/null +++ b/tests/ui/half-open-range-patterns/half-open-range-pats-inclusive-match-arrow.rs @@ -0,0 +1,8 @@ +fn main() { + let x = 42; + match x { + 0..=73 => {}, + 74..=> {}, //~ ERROR unexpected `=>` after open range + //~^ ERROR expected one of `=>`, `if`, or `|`, found `>` + } +} diff --git a/tests/ui/half-open-range-patterns/half-open-range-pats-inclusive-match-arrow.stderr b/tests/ui/half-open-range-patterns/half-open-range-pats-inclusive-match-arrow.stderr new file mode 100644 index 00000000000..9ba6d15113c --- /dev/null +++ b/tests/ui/half-open-range-patterns/half-open-range-pats-inclusive-match-arrow.stderr @@ -0,0 +1,19 @@ +error: unexpected `=>` after open range + --> $DIR/half-open-range-pats-inclusive-match-arrow.rs:5:11 + | +LL | 74..=> {}, + | ^^^ + | +help: add a space between the pattern and `=>` + | +LL | 74.. => {}, + | + + +error: expected one of `=>`, `if`, or `|`, found `>` + --> $DIR/half-open-range-pats-inclusive-match-arrow.rs:5:14 + | +LL | 74..=> {}, + | ^ expected one of `=>`, `if`, or `|` + +error: aborting due to 2 previous errors +