Added comment to tests/ui/match/match-option-result-mismatch.rs

Author: reddevilmidzy

tests/ui/match/match-option-result-mismatch.rs

@@ -1,6 +1,9 @@
+//! regression test for <https://github.com/rust-lang/rust/issues/3680>
+
 fn main() {
-    match None { //~ NOTE this expression has type `Option<_>`
-        Err(_) => ()
+    match None {
+        //~^ NOTE this expression has type `Option<_>`
+        Err(_) => (),
         //~^ ERROR mismatched types
         //~| NOTE expected enum `Option<_>`
         //~| NOTE found enum `Result<_, _>`

tests/ui/match/match-option-result-mismatch.stderr

@@ -1,16 +1,17 @@
 error[E0308]: mismatched types
-  --> $DIR/issue-3680.rs:3:9
+  --> $DIR/match-option-result-mismatch.rs:6:9
    |
 LL |     match None {
    |           ---- this expression has type `Option<_>`
-LL |         Err(_) => ()
+LL |
+LL |         Err(_) => (),
    |         ^^^^^^ expected `Option<_>`, found `Result<_, _>`
    |
    = note: expected enum `Option<_>`
               found enum `Result<_, _>`
 help: try wrapping the pattern in `Some`
    |
-LL |         Some(Err(_)) => ()
+LL |         Some(Err(_)) => (),
    |         +++++      +
 
 error: aborting due to 1 previous error