Merge pull request #1931 from santoshxshrestha/patch-2

added a shorthand for the #[should_panic(expected = "msg")

Author: marioidival

src/testing/unit_testing.md

@@ -107,6 +107,10 @@ To check functions that should panic under certain circumstances, use attribute
 the text of the panic message. If your function can panic in multiple ways, it helps
 make sure your test is testing the correct panic.
 
+**Note**: Rust also allows a shorthand form `#[should_panic = "message"]`, which works
+exactly like `#[should_panic(expected = "message")]`. Both are valid; the latter is more commonly
+used and is considered more explicit.
+
 ```rust,ignore
 pub fn divide_non_zero_result(a: u32, b: u32) -> u32 {
     if b == 0 {
@@ -137,6 +141,12 @@ mod tests {
     fn test_specific_panic() {
         divide_non_zero_result(1, 10);
     }
+
+    #[test]
+    #[should_panic = "Divide result is zero"] // This also works
+    fn test_specific_panic_shorthand() {
+        divide_non_zero_result(1, 10);
+    }
 }
 ```
 
@@ -149,8 +159,9 @@ running 3 tests
 test tests::test_any_panic ... ok
 test tests::test_divide ... ok
 test tests::test_specific_panic ... ok
+test tests::test_specific_panic_shorthand ... ok
 
-test result: ok. 3 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
+test result: ok. 4 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
 
    Doc-tests tmp-test-should-panic