From 0c203965e2a5aca6750f90777003adad2b79849f Mon Sep 17 00:00:00 2001
From: Wim Looman <wim@nemo157.com>
Date: Tue, 6 Nov 2018 19:47:18 +0100
Subject: [PATCH] impl Generator for Pin<Box<Generator>>

---
 src/liballoc/boxed.rs                            | 10 ++++++++++
 src/test/run-pass/generator/pin-box-generator.rs | 13 +++++++++++++
 2 files changed, 23 insertions(+)
 create mode 100644 src/test/run-pass/generator/pin-box-generator.rs

diff --git a/src/liballoc/boxed.rs b/src/liballoc/boxed.rs
index 1fd8aa98cc3..14a1242e3e5 100644
--- a/src/liballoc/boxed.rs
+++ b/src/liballoc/boxed.rs
@@ -882,6 +882,16 @@ impl<G: ?Sized + Generator + Unpin> Generator for Box<G> {
     }
 }
 
+#[unstable(feature = "generator_trait", issue = "43122")]
+impl<G: ?Sized + Generator> Generator for Pin<Box<G>> {
+    type Yield = G::Yield;
+    type Return = G::Return;
+
+    fn resume(mut self: Pin<&mut Self>) -> GeneratorState<Self::Yield, Self::Return> {
+        G::resume((*self).as_mut())
+    }
+}
+
 #[unstable(feature = "futures_api", issue = "50547")]
 impl<F: ?Sized + Future + Unpin> Future for Box<F> {
     type Output = F::Output;
diff --git a/src/test/run-pass/generator/pin-box-generator.rs b/src/test/run-pass/generator/pin-box-generator.rs
new file mode 100644
index 00000000000..c3136f5c0ec
--- /dev/null
+++ b/src/test/run-pass/generator/pin-box-generator.rs
@@ -0,0 +1,13 @@
+// run-pass
+
+#![feature(generators, generator_trait)]
+
+use std::ops::Generator;
+
+fn assert_generator<G: Generator>(_: G) {
+}
+
+fn main() {
+    assert_generator(static || yield);
+    assert_generator(Box::pin(static || yield));
+}