add rustdoc test for async fn reexport

src/test/rustdoc/inline_cross/auxiliary/impl_trait_aux.rs

@@ -1,3 +1,5 @@
+// edition:2018
+
 use std::ops::Deref;
 
 pub fn func<'a>(_x: impl Clone + Into<Vec<u8>> + 'a) {}
@@ -11,8 +13,16 @@ pub fn func3(_x: impl Iterator<Item = impl Iterator<Item = u8>> + Clone) {}
 
 pub fn func4<T: Iterator<Item = impl Clone>>(_x: T) {}
 
+pub async fn async_fn() {}
+
 pub struct Foo;
 
 impl Foo {
     pub fn method<'a>(_x: impl Clone + Into<Vec<u8>> + 'a) {}
 }
+
+pub struct Bar;
+
+impl Bar {
+    pub async fn async_foo(&self) {}
+}

src/test/rustdoc/inline_cross/impl_trait.rs

@@ -1,4 +1,5 @@
 // aux-build:impl_trait_aux.rs
+// edition:2018
 
 extern crate impl_trait_aux;
 
@@ -20,13 +21,20 @@ pub use impl_trait_aux::func2;
 // @!has - '//pre[@class="rust fn"]' 'where'
 pub use impl_trait_aux::func3;
 
-
 // @has impl_trait/fn.func4.html
 // @has - '//pre[@class="rust fn"]' "func4<T>("
 // @has - '//pre[@class="rust fn"]' "T: Iterator<Item = impl Clone>,"
 pub use impl_trait_aux::func4;
 
+// @has impl_trait/fn.async_fn.html
+// @has - '//pre[@class="rust fn"]' "pub async fn async_fn()"
+pub use impl_trait_aux::async_fn;
+
 // @has impl_trait/struct.Foo.html
 // @has - '//code[@id="method.v"]' "pub fn method<'a>(_x: impl Clone + Into<Vec<u8>> + 'a)"
 // @!has - '//code[@id="method.v"]' 'where'
 pub use impl_trait_aux::Foo;
+
+// @has impl_trait/struct.Bar.html
+// @has - '//*[@id="method.async_foo"]' "pub async fn async_foo("
+pub use impl_trait_aux::Bar;