From d328dbc60f51a70f0c6eeec644af303719e563a4 Mon Sep 17 00:00:00 2001
From: marmeladema <xademax@gmail.com>
Date: Wed, 21 Apr 2021 00:07:42 +0100
Subject: [PATCH] Add test for issue #71176

---
 .../generic-associated-types/issue-71176.rs   | 21 +++++++++++++++++++
 .../issue-71176.stderr                        | 19 +++++++++++++++++
 2 files changed, 40 insertions(+)
 create mode 100644 src/test/ui/generic-associated-types/issue-71176.rs
 create mode 100644 src/test/ui/generic-associated-types/issue-71176.stderr

diff --git a/src/test/ui/generic-associated-types/issue-71176.rs b/src/test/ui/generic-associated-types/issue-71176.rs
new file mode 100644
index 00000000000..470476bf476
--- /dev/null
+++ b/src/test/ui/generic-associated-types/issue-71176.rs
@@ -0,0 +1,21 @@
+#![allow(incomplete_features)]
+#![feature(generic_associated_types)]
+
+trait Provider {
+    type A<'a>;
+      //~^ ERROR: missing generics for associated type
+}
+
+impl Provider for () {
+    type A<'a> = ();
+}
+
+struct Holder<B> {
+  inner: Box<dyn Provider<A = B>>,
+}
+
+fn main() {
+    Holder {
+        inner: Box::new(()),
+    };
+}
diff --git a/src/test/ui/generic-associated-types/issue-71176.stderr b/src/test/ui/generic-associated-types/issue-71176.stderr
new file mode 100644
index 00000000000..dd19dd4ad8e
--- /dev/null
+++ b/src/test/ui/generic-associated-types/issue-71176.stderr
@@ -0,0 +1,19 @@
+error[E0107]: missing generics for associated type `Provider::A`
+  --> $DIR/issue-71176.rs:5:10
+   |
+LL |     type A<'a>;
+   |          ^ expected 1 lifetime argument
+   |
+note: associated type defined here, with 1 lifetime parameter: `'a`
+  --> $DIR/issue-71176.rs:5:10
+   |
+LL |     type A<'a>;
+   |          ^ --
+help: use angle brackets to add missing lifetime argument
+   |
+LL |     type A<'a><'a>;
+   |           ^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0107`.