diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs index 350a372a684..98c7b9a63a5 100644 --- a/compiler/rustc_parse/src/parser/diagnostics.rs +++ b/compiler/rustc_parse/src/parser/diagnostics.rs @@ -1912,4 +1912,22 @@ impl<'a> Parser<'a> { *self = snapshot; Err(err) } + + /// Get the diagnostics for the cases where `move async` is found. + /// + /// `move_async_span` starts at the 'm' of the move keyword and ends with the 'c' of the async keyword + pub(super) fn incorrect_move_async_order_found( + &self, + move_async_span: Span, + ) -> DiagnosticBuilder<'a> { + let mut err = + self.struct_span_err(move_async_span, "the order of `move` and `async` is incorrect"); + err.span_suggestion_verbose( + move_async_span, + "try switching the order", + "async move".to_owned(), + Applicability::MaybeIncorrect, + ); + err + } } diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index 93be478fc8c..7d0d4f30137 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -1603,7 +1603,7 @@ impl<'a> Parser<'a> { self.sess.gated_spans.gate(sym::async_closure, span); } - let capture_clause = self.parse_capture_clause(); + let capture_clause = self.parse_capture_clause()?; let decl = self.parse_fn_block_decl()?; let decl_hi = self.prev_token.span; let body = match decl.output { @@ -1626,8 +1626,18 @@ impl<'a> Parser<'a> { } /// Parses an optional `move` prefix to a closure-like construct. - fn parse_capture_clause(&mut self) -> CaptureBy { - if self.eat_keyword(kw::Move) { CaptureBy::Value } else { CaptureBy::Ref } + fn parse_capture_clause(&mut self) -> PResult<'a, CaptureBy> { + if self.eat_keyword(kw::Move) { + // Check for `move async` and recover + if self.check_keyword(kw::Async) { + let move_async_span = self.token.span.with_lo(self.prev_token.span.data().lo); + Err(self.incorrect_move_async_order_found(move_async_span)) + } else { + Ok(CaptureBy::Value) + } + } else { + Ok(CaptureBy::Ref) + } } /// Parses the `|arg, arg|` header of a closure. @@ -2018,7 +2028,7 @@ impl<'a> Parser<'a> { fn parse_async_block(&mut self, mut attrs: AttrVec) -> PResult<'a, P> { let lo = self.token.span; self.expect_keyword(kw::Async)?; - let capture_clause = self.parse_capture_clause(); + let capture_clause = self.parse_capture_clause()?; let (iattrs, body) = self.parse_inner_attrs_and_block()?; attrs.extend(iattrs); let kind = ExprKind::Async(capture_clause, DUMMY_NODE_ID, body); diff --git a/src/test/ui/parser/incorrect-move-async-order-issue-79694.fixed b/src/test/ui/parser/incorrect-move-async-order-issue-79694.fixed new file mode 100644 index 00000000000..055800d23b6 --- /dev/null +++ b/src/test/ui/parser/incorrect-move-async-order-issue-79694.fixed @@ -0,0 +1,8 @@ +// run-rustfix +// edition:2018 + +// Regression test for issue 79694 + +fn main() { + let _ = async move { }; //~ ERROR 7:13: 7:23: the order of `move` and `async` is incorrect +} diff --git a/src/test/ui/parser/incorrect-move-async-order-issue-79694.rs b/src/test/ui/parser/incorrect-move-async-order-issue-79694.rs new file mode 100644 index 00000000000..e8be16516d6 --- /dev/null +++ b/src/test/ui/parser/incorrect-move-async-order-issue-79694.rs @@ -0,0 +1,8 @@ +// run-rustfix +// edition:2018 + +// Regression test for issue 79694 + +fn main() { + let _ = move async { }; //~ ERROR 7:13: 7:23: the order of `move` and `async` is incorrect +} diff --git a/src/test/ui/parser/incorrect-move-async-order-issue-79694.stderr b/src/test/ui/parser/incorrect-move-async-order-issue-79694.stderr new file mode 100644 index 00000000000..2add9fb33c7 --- /dev/null +++ b/src/test/ui/parser/incorrect-move-async-order-issue-79694.stderr @@ -0,0 +1,13 @@ +error: the order of `move` and `async` is incorrect + --> $DIR/incorrect-move-async-order-issue-79694.rs:7:13 + | +LL | let _ = move async { }; + | ^^^^^^^^^^ + | +help: try switching the order + | +LL | let _ = async move { }; + | ^^^^^^^^^^ + +error: aborting due to previous error +