From 517ca598d381f6d8778b63a4edd259778e61b994 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Esteban=20K=C3=BCber?= <esteban@kuber.com.ar>
Date: Wed, 18 Oct 2023 21:37:21 +0000
Subject: [PATCH] Add test

---
 .../object/object-unsafe-missing-assoc-type.rs |  7 +++++++
 .../object-unsafe-missing-assoc-type.stderr    | 18 ++++++++++++++++++
 2 files changed, 25 insertions(+)
 create mode 100644 tests/ui/traits/object/object-unsafe-missing-assoc-type.rs
 create mode 100644 tests/ui/traits/object/object-unsafe-missing-assoc-type.stderr

diff --git a/tests/ui/traits/object/object-unsafe-missing-assoc-type.rs b/tests/ui/traits/object/object-unsafe-missing-assoc-type.rs
new file mode 100644
index 0000000000000..21f7fd92e80da
--- /dev/null
+++ b/tests/ui/traits/object/object-unsafe-missing-assoc-type.rs
@@ -0,0 +1,7 @@
+trait Foo {
+    type Bar<T>;
+}
+
+fn bar(x: &dyn Foo) {} //~ ERROR the trait `Foo` cannot be made into an object
+
+fn main() {}
diff --git a/tests/ui/traits/object/object-unsafe-missing-assoc-type.stderr b/tests/ui/traits/object/object-unsafe-missing-assoc-type.stderr
new file mode 100644
index 0000000000000..fcaa583e2bd45
--- /dev/null
+++ b/tests/ui/traits/object/object-unsafe-missing-assoc-type.stderr
@@ -0,0 +1,18 @@
+error[E0038]: the trait `Foo` cannot be made into an object
+  --> $DIR/object-unsafe-missing-assoc-type.rs:5:16
+   |
+LL | fn bar(x: &dyn Foo) {}
+   |                ^^^ `Foo` cannot be made into an object
+   |
+note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
+  --> $DIR/object-unsafe-missing-assoc-type.rs:2:10
+   |
+LL | trait Foo {
+   |       --- this trait cannot be made into an object...
+LL |     type Bar<T>;
+   |          ^^^ ...because it contains the generic associated type `Bar`
+   = help: consider moving `Bar` to another trait
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0038`.