Rollup merge of #97759 - WaffleLapkin:recover_label_expr, r=compiler-errors

Suggest adding `{}` for `'label: non_block_expr`

Adds suggestions like this:
```text
help: consider enclosing expression in a block
  |
3 |     'l {0};
  |        + +
```

inspired by https://github.com/rust-lang/rust/issues/48594#issuecomment-1146744400

r? ``@compiler-errors``

4 files changed, 126 insertions, 13 deletions

diff --git a/src/test/ui/parser/labeled-no-colon-expr.stderr b/src/test/ui/parser/labeled-no-colon-expr.stderr
index 26884dc5d74..5c9597c440c 100644
--- a/src/test/ui/parser/labeled-no-colon-expr.stderr
+++ b/src/test/ui/parser/labeled-no-colon-expr.stderr
@@ -47,6 +47,12 @@ error: expected `while`, `for`, `loop` or `{` after a label
    |
 LL |     'l4 0;
    |         ^ expected `while`, `for`, `loop` or `{` after a label
+   |
+help: consider removing the label
+   |
+LL -     'l4 0;
+LL +     0;
+   | 
 
 error: labeled expression must be followed by `:`
   --> $DIR/labeled-no-colon-expr.rs:8:9
diff --git a/src/test/ui/parser/recover-labeled-non-block-expr.fixed b/src/test/ui/parser/recover-labeled-non-block-expr.fixed
new file mode 100644
index 00000000000..fe546a71971
--- /dev/null
+++ b/src/test/ui/parser/recover-labeled-non-block-expr.fixed
@@ -0,0 +1,27 @@
+// run-rustfix
+#![feature(label_break_value)]
+fn main() {
+    let _ = 1 + 1; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+
+    match () { () => {}, }; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+    'label: { match () { () => break 'label, } }; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+    #[allow(unused_labels)]
+    'label: { match () { () => 'lp: loop { break 'lp 0 }, } }; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+
+    let x = 1;
+    let _i = 'label: { match x { //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+        0 => 42,
+        1 if false => break 'label 17,
+        1 => {
+            if true {
+                break 'label 13
+            } else {
+                break 'label 0;
+            }
+        }
+        _ => 1,
+    } };
+
+    let other = 3;
+    let _val = 'label: { (1, if other == 3 { break 'label (2, 3) } else { other }) }; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+}
diff --git a/src/test/ui/parser/recover-labeled-non-block-expr.rs b/src/test/ui/parser/recover-labeled-non-block-expr.rs
index be92170acf0..35862e2eef9 100644
--- a/src/test/ui/parser/recover-labeled-non-block-expr.rs
+++ b/src/test/ui/parser/recover-labeled-non-block-expr.rs
@@ -1,5 +1,27 @@
+// run-rustfix
+#![feature(label_break_value)]
 fn main() {
-    'label: 1 + 1; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+    let _ = 'label: 1 + 1; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
 
-    let _recovery_witness: () = 0; //~ ERROR mismatched types
+    'label: match () { () => {}, }; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+    'label: match () { () => break 'label, }; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+    #[allow(unused_labels)]
+    'label: match () { () => 'lp: loop { break 'lp 0 }, }; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+
+    let x = 1;
+    let _i = 'label: match x { //~ ERROR expected `while`, `for`, `loop` or `{` after a label
+        0 => 42,
+        1 if false => break 'label 17,
+        1 => {
+            if true {
+                break 'label 13
+            } else {
+                break 'label 0;
+            }
+        }
+        _ => 1,
+    };
+
+    let other = 3;
+    let _val = 'label: (1, if other == 3 { break 'label (2, 3) } else { other }); //~ ERROR expected `while`, `for`, `loop` or `{` after a label
 }
diff --git a/src/test/ui/parser/recover-labeled-non-block-expr.stderr b/src/test/ui/parser/recover-labeled-non-block-expr.stderr
index 771a915288c..767389c4808 100644
--- a/src/test/ui/parser/recover-labeled-non-block-expr.stderr
+++ b/src/test/ui/parser/recover-labeled-non-block-expr.stderr
@@ -1,17 +1,75 @@
 error: expected `while`, `for`, `loop` or `{` after a label
-  --> $DIR/recover-labeled-non-block-expr.rs:2:13
+  --> $DIR/recover-labeled-non-block-expr.rs:4:21
    |
-LL |     'label: 1 + 1;
-   |             ^ expected `while`, `for`, `loop` or `{` after a label
+LL |     let _ = 'label: 1 + 1;
+   |                     ^ expected `while`, `for`, `loop` or `{` after a label
+   |
+help: consider removing the label
+   |
+LL -     let _ = 'label: 1 + 1;
+LL +     let _ = 1 + 1;
+   | 
+
+error: expected `while`, `for`, `loop` or `{` after a label
+  --> $DIR/recover-labeled-non-block-expr.rs:6:13
+   |
+LL |     'label: match () { () => {}, };
+   |             ^^^^^ expected `while`, `for`, `loop` or `{` after a label
+   |
+help: consider removing the label
+   |
+LL -     'label: match () { () => {}, };
+LL +     match () { () => {}, };
+   | 
 
-error[E0308]: mismatched types
-  --> $DIR/recover-labeled-non-block-expr.rs:4:33
+error: expected `while`, `for`, `loop` or `{` after a label
+  --> $DIR/recover-labeled-non-block-expr.rs:7:13
+   |
+LL |     'label: match () { () => break 'label, };
+   |             ^^^^^ expected `while`, `for`, `loop` or `{` after a label
+   |
+help: consider enclosing expression in a block
+   |
+LL |     'label: { match () { () => break 'label, } };
+   |             +                                  +
+
+error: expected `while`, `for`, `loop` or `{` after a label
+  --> $DIR/recover-labeled-non-block-expr.rs:9:13
+   |
+LL |     'label: match () { () => 'lp: loop { break 'lp 0 }, };
+   |             ^^^^^ expected `while`, `for`, `loop` or `{` after a label
+   |
+help: consider enclosing expression in a block
+   |
+LL |     'label: { match () { () => 'lp: loop { break 'lp 0 }, } };
+   |             +                                               +
+
+error: expected `while`, `for`, `loop` or `{` after a label
+  --> $DIR/recover-labeled-non-block-expr.rs:12:22
+   |
+LL |     let _i = 'label: match x {
+   |                      ^^^^^ expected `while`, `for`, `loop` or `{` after a label
+   |
+help: consider enclosing expression in a block
+   |
+LL ~     let _i = 'label: { match x {
+LL |         0 => 42,
+LL |         1 if false => break 'label 17,
+LL |         1 => {
+LL |             if true {
+LL |                 break 'label 13
+ ...
+
+error: expected `while`, `for`, `loop` or `{` after a label
+  --> $DIR/recover-labeled-non-block-expr.rs:26:24
+   |
+LL |     let _val = 'label: (1, if other == 3 { break 'label (2, 3) } else { other });
+   |                        ^ expected `while`, `for`, `loop` or `{` after a label
+   |
+help: consider enclosing expression in a block
    |
-LL |     let _recovery_witness: () = 0;
-   |                            --   ^ expected `()`, found integer
-   |                            |
-   |                            expected due to this
+LL |     let _val = 'label: { (1, if other == 3 { break 'label (2, 3) } else { other }) };
+   |                        +                                                           +
 
-error: aborting due to 2 previous errors
+error: aborting due to 6 previous errors
 
-For more information about this error, try `rustc --explain E0308`.