recover const Tr bounds (no ~)

2022-08-21 14:58:42 +04:00
parent 798016c2df
commit 5d5e451618
3 changed files with 20 additions and 11 deletions
--- a/compiler/rustc_parse/src/parser/ty.rs
+++ b/compiler/rustc_parse/src/parser/ty.rs
@@ -809,6 +809,20 @@ impl<'a> Parser<'a> {
            self.expect_keyword(kw::Const)?;
            let span = tilde.to(self.prev_token.span);
            self.sess.gated_spans.gate(sym::const_trait_impl, span);
+            Some(span)
+        } else if self.eat_keyword(kw::Const) {
+            let span = self.prev_token.span;
+            self.sess.gated_spans.gate(sym::const_trait_impl, span);
+
+            self.struct_span_err(span, "const bounds must start with `~`")
+                .span_suggestion(
+                    span.shrink_to_lo(),
+                    "add `~`",
+                    "~",
+                    Applicability::MachineApplicable,
+                )
+                .emit();
+
            Some(span)
        } else {
            None