diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs index 7dc4fd0044f1f..c609aa93da3a7 100644 --- a/compiler/rustc_parse/src/parser/diagnostics.rs +++ b/compiler/rustc_parse/src/parser/diagnostics.rs @@ -2468,11 +2468,15 @@ impl<'a> Parser<'a> { } pub(crate) fn maybe_recover_unexpected_block_label(&mut self) -> bool { - let Some(label) = self.eat_label().filter(|_| { - self.eat(&token::Colon) && self.token.kind == token::OpenDelim(Delimiter::Brace) - }) else { + // Check for `'a : {` + if !(self.check_lifetime() + && self.look_ahead(1, |tok| tok.kind == token::Colon) + && self.look_ahead(2, |tok| tok.kind == token::OpenDelim(Delimiter::Brace))) + { return false; - }; + } + let label = self.eat_label().expect("just checked if a label exists"); + self.bump(); // eat `:` let span = label.ident.span.to(self.prev_token.span); let mut err = self.struct_span_err(span, "block label not supported here"); err.span_label(span, "not supported here"); diff --git a/src/test/ui/parser/label-after-block-like.rs b/src/test/ui/parser/label-after-block-like.rs new file mode 100644 index 0000000000000..55f3f8f9f5f03 --- /dev/null +++ b/src/test/ui/parser/label-after-block-like.rs @@ -0,0 +1,43 @@ +fn a() { + if let () = () 'a {} + //~^ ERROR labeled expression must be followed by `:` + //~| ERROR expected `{`, found `'a` +} + +fn b() { + if true 'a {} + //~^ ERROR labeled expression must be followed by `:` + //~| ERROR expected `{`, found `'a` +} + +fn c() { + loop 'a {} + //~^ ERROR labeled expression must be followed by `:` + //~| ERROR expected `{`, found `'a` +} + +fn d() { + while true 'a {} + //~^ ERROR labeled expression must be followed by `:` + //~| ERROR expected `{`, found `'a` +} + +fn e() { + while let () = () 'a {} + //~^ ERROR labeled expression must be followed by `:` + //~| ERROR expected `{`, found `'a` +} + +fn f() { + for _ in 0..0 'a {} + //~^ ERROR labeled expression must be followed by `:` + //~| ERROR expected `{`, found `'a` +} + +fn g() { + unsafe 'a {} + //~^ ERROR labeled expression must be followed by `:` + //~| ERROR expected `{`, found `'a` +} + +fn main() {} diff --git a/src/test/ui/parser/label-after-block-like.stderr b/src/test/ui/parser/label-after-block-like.stderr new file mode 100644 index 0000000000000..8ff50b124b32b --- /dev/null +++ b/src/test/ui/parser/label-after-block-like.stderr @@ -0,0 +1,176 @@ +error: labeled expression must be followed by `:` + --> $DIR/label-after-block-like.rs:2:20 + | +LL | if let () = () 'a {} + | ---^^ + | | | + | | help: add `:` after the label + | the label + | + = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them + +error: expected `{`, found `'a` + --> $DIR/label-after-block-like.rs:2:20 + | +LL | if let () = () 'a {} + | ^^ expected `{` + | +note: the `if` expression is missing a block after this condition + --> $DIR/label-after-block-like.rs:2:8 + | +LL | if let () = () 'a {} + | ^^^^^^^^^^^ +help: try placing this code inside a block + | +LL | if let () = () { 'a {} } + | + + + +error: labeled expression must be followed by `:` + --> $DIR/label-after-block-like.rs:8:13 + | +LL | if true 'a {} + | ---^^ + | | | + | | help: add `:` after the label + | the label + | + = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them + +error: expected `{`, found `'a` + --> $DIR/label-after-block-like.rs:8:13 + | +LL | if true 'a {} + | ^^ expected `{` + | +note: the `if` expression is missing a block after this condition + --> $DIR/label-after-block-like.rs:8:8 + | +LL | if true 'a {} + | ^^^^ +help: try placing this code inside a block + | +LL | if true { 'a {} } + | + + + +error: labeled expression must be followed by `:` + --> $DIR/label-after-block-like.rs:14:10 + | +LL | loop 'a {} + | ---^^ + | | | + | | help: add `:` after the label + | the label + | + = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them + +error: expected `{`, found `'a` + --> $DIR/label-after-block-like.rs:14:10 + | +LL | loop 'a {} + | ---- ^^ expected `{` + | | + | while parsing this `loop` expression + | +help: try placing this code inside a block + | +LL | loop { 'a {} } + | + + + +error: labeled expression must be followed by `:` + --> $DIR/label-after-block-like.rs:20:16 + | +LL | while true 'a {} + | ---^^ + | | | + | | help: add `:` after the label + | the label + | + = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them + +error: expected `{`, found `'a` + --> $DIR/label-after-block-like.rs:20:16 + | +LL | while true 'a {} + | ----- ---- ^^ expected `{` + | | | + | | this `while` condition successfully parsed + | while parsing the body of this `while` expression + | +help: try placing this code inside a block + | +LL | while true { 'a {} } + | + + + +error: labeled expression must be followed by `:` + --> $DIR/label-after-block-like.rs:26:23 + | +LL | while let () = () 'a {} + | ---^^ + | | | + | | help: add `:` after the label + | the label + | + = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them + +error: expected `{`, found `'a` + --> $DIR/label-after-block-like.rs:26:23 + | +LL | while let () = () 'a {} + | ----- ----------- ^^ expected `{` + | | | + | | this `while` condition successfully parsed + | while parsing the body of this `while` expression + | +help: try placing this code inside a block + | +LL | while let () = () { 'a {} } + | + + + +error: labeled expression must be followed by `:` + --> $DIR/label-after-block-like.rs:32:19 + | +LL | for _ in 0..0 'a {} + | ---^^ + | | | + | | help: add `:` after the label + | the label + | + = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them + +error: expected `{`, found `'a` + --> $DIR/label-after-block-like.rs:32:19 + | +LL | for _ in 0..0 'a {} + | ^^ expected `{` + | +help: try placing this code inside a block + | +LL | for _ in 0..0 { 'a {} } + | + + + +error: labeled expression must be followed by `:` + --> $DIR/label-after-block-like.rs:38:12 + | +LL | unsafe 'a {} + | ---^^ + | | | + | | help: add `:` after the label + | the label + | + = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them + +error: expected `{`, found `'a` + --> $DIR/label-after-block-like.rs:38:12 + | +LL | unsafe 'a {} + | ------ ^^ expected `{` + | | + | while parsing this `unsafe` expression + | +help: try placing this code inside a block + | +LL | unsafe { 'a {} } + | + + + +error: aborting due to 14 previous errors +