2 files changed, 18 insertions, 1 deletions
diff --git a/tests/ui/diagnostic_namespace/suggest_typos.rs b/tests/ui/diagnostic_namespace/suggest_typos.rs
index 6fa4f800462..8d1dc6f59da 100644
--- a/tests/ui/diagnostic_namespace/suggest_typos.rs
+++ b/tests/ui/diagnostic_namespace/suggest_typos.rs
@@ -16,4 +16,9 @@ trait Y{}
 //~^^HELP an attribute with a similar name exists
 trait Z{}
 
+#[diagnostic::dont_recommend]
+//~^ERROR unknown diagnostic attribute
+//~^^HELP an attribute with a similar name exists
+impl X for u8 {}
+
 fn main(){}
diff --git a/tests/ui/diagnostic_namespace/suggest_typos.stderr b/tests/ui/diagnostic_namespace/suggest_typos.stderr
index 86d778c6ec0..1f19fd4bbcf 100644
--- a/tests/ui/diagnostic_namespace/suggest_typos.stderr
+++ b/tests/ui/diagnostic_namespace/suggest_typos.stderr
@@ -37,5 +37,17 @@ help: an attribute with a similar name exists
 LL | #[diagnostic::on_unimplemented]
    |                  ++
 
-error: aborting due to 3 previous errors
+error: unknown diagnostic attribute
+  --> $DIR/suggest_typos.rs:19:15
+   |
+LL | #[diagnostic::dont_recommend]
+   |               ^^^^^^^^^^^^^^
+   |
+help: an attribute with a similar name exists
+   |
+LL - #[diagnostic::dont_recommend]
+LL + #[diagnostic::do_not_recommend]
+   |
+
+error: aborting due to 4 previous errors