From 690e0370081d39c2a4c459e5fd74a6e3728b73a9 Mon Sep 17 00:00:00 2001
From: Maybe Waffle <waffle.lapkin@gmail.com>
Date: Fri, 29 Jul 2022 02:28:36 +0400
Subject: [PATCH] add a test for gate `impl_trait_in_fn_trait_return`

---
 .../feature-gate-impl_trait_in_fn_trait_return.rs |  6 ++++++
 ...ture-gate-impl_trait_in_fn_trait_return.stderr | 15 +++++++++++++++
 2 files changed, 21 insertions(+)
 create mode 100644 src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.rs
 create mode 100644 src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.stderr

diff --git a/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.rs b/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.rs
new file mode 100644
index 000000000000..0db8088f7eea
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.rs
@@ -0,0 +1,6 @@
+fn f() -> impl Fn() -> impl Sized { || () }
+//~^ ERROR `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
+fn g() -> &'static dyn Fn() -> impl Sized { &|| () }
+//~^ ERROR `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
+
+fn main() {}
diff --git a/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.stderr b/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.stderr
new file mode 100644
index 000000000000..c485bc5c3ab9
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.stderr
@@ -0,0 +1,15 @@
+error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
+  --> $DIR/feature-gate-impl_trait_in_fn_trait_return.rs:1:24
+   |
+LL | fn f() -> impl Fn() -> impl Sized { || () }
+   |                        ^^^^^^^^^^
+
+error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
+  --> $DIR/feature-gate-impl_trait_in_fn_trait_return.rs:3:32
+   |
+LL | fn g() -> &'static dyn Fn() -> impl Sized { &|| () }
+   |                                ^^^^^^^^^^
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0562`.