recover from loop...else

Author: y21

compiler/rustc_parse/src/parser/expr.rs

@@ -2550,6 +2550,7 @@ impl<'a> Parser<'a> {
     fn parse_loop_expr(&mut self, opt_label: Option<Label>, lo: Span) -> PResult<'a, P<Expr>> {
         let loop_span = self.prev_token.span;
         let (attrs, body) = self.parse_inner_attrs_and_block()?;
+        self.recover_loop_else("loop", lo)?;
         Ok(self.mk_expr_with_attrs(
             lo.to(self.prev_token.span),
             ExprKind::Loop(body, opt_label, loop_span),

tests/ui/loops/loop-else-err.rs

@@ -0,0 +1,8 @@
+fn main() {
+    loop {
+        //~^ NOTE `else` is attached to this loop
+    } else {
+        //~^ ERROR `loop...else` loops are not supported
+        //~| NOTE consider moving this `else` clause to a separate `if` statement and use a `bool` variable to control if it should run
+    }
+}

tests/ui/loops/loop-else-err.stderr

@@ -0,0 +1,17 @@
+error: `loop...else` loops are not supported
+  --> $DIR/loop-else-err.rs:4:7
+   |
+LL |       loop {
+   |       ---- `else` is attached to this loop
+LL |
+LL |       } else {
+   |  _______^
+LL | |
+LL | |
+LL | |     }
+   | |_____^
+   |
+   = note: consider moving this `else` clause to a separate `if` statement and use a `bool` variable to control if it should run
+
+error: aborting due to previous error
+

tests/ui/loops/loop-else-let-else-err.rs

@@ -0,0 +1,8 @@
+fn main() {
+    let _ = loop {
+        //~^ NOTE `else` is attached to this loop
+    } else {
+        //~^ ERROR `loop...else` loops are not supported
+        //~| NOTE consider moving this `else` clause to a separate `if` statement and use a `bool` variable to control if it should run
+    };
+}

tests/ui/loops/loop-else-let-else-err.stderr

@@ -0,0 +1,17 @@
+error: `loop...else` loops are not supported
+  --> $DIR/loop-else-let-else-err.rs:4:7
+   |
+LL |       let _ = loop {
+   |               ---- `else` is attached to this loop
+LL |
+LL |       } else {
+   |  _______^
+LL | |
+LL | |
+LL | |     };
+   | |_____^
+   |
+   = note: consider moving this `else` clause to a separate `if` statement and use a `bool` variable to control if it should run
+
+error: aborting due to previous error
+