Allow reborrowing Pin<&mut Self>

tests/ui/async-await/pin-reborrow-self.rs

@@ -1,24 +1,34 @@
 //@ check-pass
-//@ignore-test
-
-// Currently ignored due to self reborrowing not being implemented for Pin
 
 #![feature(pin_ergonomics)]
 #![allow(incomplete_features)]
 
 use std::pin::Pin;
 
-struct Foo;
+pub struct Foo;
 
 impl Foo {
     fn foo(self: Pin<&mut Self>) {
     }
+
+    fn baz(self: Pin<&Self>) {
+    }
 }
 
-fn bar(x: Pin<&mut Foo>) {
+pub fn bar(x: Pin<&mut Foo>) {
     x.foo();
     x.foo(); // for this to work we need to automatically reborrow,
              // as if the user had written `x.as_mut().foo()`.
+
+    Foo::baz(x);
+
+    // FIXME: We should allow downgrading a Pin<&mut T> to Pin<&T>
+    // x.baz();
+}
+
+pub fn baaz(x: Pin<&Foo>) {
+    x.baz();
+    x.baz();
 }
 
 fn main() {}