1 files changed, 38 insertions, 0 deletions
diff --git a/tests/ui/trait-bounds/fix-dyn-sized-fn-param-sugg.rs b/tests/ui/trait-bounds/fix-dyn-sized-fn-param-sugg.rs
new file mode 100644
index 00000000000..1aa36207bc3
--- /dev/null
+++ b/tests/ui/trait-bounds/fix-dyn-sized-fn-param-sugg.rs
@@ -0,0 +1,38 @@
+// Test that we emit a correct structured suggestions for dynamically sized ("maybe unsized")
+// function parameters.
+// We used to emit a butchered suggestion if duplicate relaxed `Sized` bounds were present.
+// issue: <https://github.com/rust-lang/rust/issues/127441>.
+
+use std::fmt::Debug;
+
+fn foo1<T: ?Sized>(a: T) {}
+//~^ ERROR the size for values of type `T` cannot be known at compilation time
+
+fn foo2<T: ?Sized + ?Sized>(a: T) {}
+//~^ ERROR duplicate relaxed `Sized` bounds
+//~| ERROR the size for values of type `T` cannot be known at compilation time
+
+fn foo3<T: ?Sized + ?Sized + Debug>(a: T) {}
+//~^ ERROR duplicate relaxed `Sized` bounds
+//~| ERROR the size for values of type `T` cannot be known at compilation time
+
+fn foo4<T: ?Sized + Debug + ?Sized >(a: T) {}
+//~^ ERROR duplicate relaxed `Sized` bounds
+//~| ERROR the size for values of type `T` cannot be known at compilation time
+
+fn foo5(_: impl ?Sized) {}
+//~^ ERROR the size for values of type `impl ?Sized` cannot be known at compilation time
+
+fn foo6(_: impl ?Sized + ?Sized) {}
+//~^ ERROR duplicate relaxed `Sized` bounds
+//~| ERROR the size for values of type `impl ?Sized + ?Sized` cannot be known at compilation tim
+
+fn foo7(_: impl ?Sized + ?Sized + Debug) {}
+//~^ ERROR duplicate relaxed `Sized` bounds
+//~| ERROR the size for values of type `impl ?Sized + ?Sized + Debug` cannot be known at compilation time
+
+fn foo8(_: impl ?Sized + Debug + ?Sized ) {}
+//~^ ERROR duplicate relaxed `Sized` bounds
+//~| ERROR the size for values of type `impl ?Sized + Debug + ?Sized` cannot be known at compilation time
+
+fn main() {}