6 files changed, 162 insertions, 0 deletions
diff --git a/tests/rustdoc/async/async-fn-opaque-item.rs b/tests/rustdoc/async/async-fn-opaque-item.rs
new file mode 100644
index 00000000000..d45183f96dd
--- /dev/null
+++ b/tests/rustdoc/async/async-fn-opaque-item.rs
@@ -0,0 +1,15 @@
+//@ compile-flags: --document-private-items --crate-type=lib
+//@ edition: 2021
+
+// Issue 109931 -- test against accidentally documenting the `impl Future`
+// that comes from an async fn desugaring.
+
+// Check that we don't document an unnamed opaque type
+//@ !has async_fn_opaque_item/opaque..html
+
+// Checking there is only a "Functions" header and no "Opaque types".
+//@ has async_fn_opaque_item/index.html
+//@ count - '//*[@class="section-header"]' 1
+//@ has - '//*[@class="section-header"]' 'Functions'
+
+pub async fn test() {}
diff --git a/tests/rustdoc/async/async-fn.rs b/tests/rustdoc/async/async-fn.rs
new file mode 100644
index 00000000000..3d49766c55e
--- /dev/null
+++ b/tests/rustdoc/async/async-fn.rs
@@ -0,0 +1,99 @@
+//@ edition:2018
+//@ has async_fn/fn.foo.html '//pre[@class="rust item-decl"]' 'pub async fn foo() -> Option<Foo>'
+pub async fn foo() -> Option<Foo> {
+    None
+}
+
+//@ has async_fn/fn.bar.html '//pre[@class="rust item-decl"]' 'pub async fn bar(a: i32, b: i32) -> i32'
+pub async fn bar(a: i32, b: i32) -> i32 {
+    0
+}
+
+//@ has async_fn/fn.baz.html '//pre[@class="rust item-decl"]' 'pub async fn baz<T>(a: T) -> T'
+pub async fn baz<T>(a: T) -> T {
+    a
+}
+
+//@ has async_fn/fn.qux.html '//pre[@class="rust item-decl"]' 'pub async unsafe fn qux() -> char'
+pub async unsafe fn qux() -> char {
+    '⚠'
+}
+
+//@ has async_fn/fn.mut_args.html '//pre[@class="rust item-decl"]' 'pub async fn mut_args(a: usize)'
+pub async fn mut_args(mut a: usize) {}
+
+//@ has async_fn/fn.mut_ref.html '//pre[@class="rust item-decl"]' 'pub async fn mut_ref(x: i32)'
+pub async fn mut_ref(ref mut x: i32) {}
+
+trait Bar {}
+
+impl Bar for () {}
+
+//@ has async_fn/fn.quux.html '//pre[@class="rust item-decl"]' 'pub async fn quux() -> impl Bar'
+pub async fn quux() -> impl Bar {
+    ()
+}
+
+//@ has async_fn/struct.Foo.html
+//@ matches - '//h4[@class="code-header"]' 'pub async fn f\(\)$'
+//@ matches - '//h4[@class="code-header"]' 'pub async unsafe fn g\(\)$'
+//@ matches - '//h4[@class="code-header"]' 'pub async fn mut_self\(self, first: usize\)$'
+pub struct Foo;
+
+impl Foo {
+    pub async fn f() {}
+    pub async unsafe fn g() {}
+    pub async fn mut_self(mut self, mut first: usize) {}
+}
+
+pub trait Pattern<'a> {}
+
+impl Pattern<'_> for () {}
+
+pub trait Trait<const N: usize> {}
+//@ has async_fn/fn.const_generics.html
+//@ has - '//pre[@class="rust item-decl"]' 'pub async fn const_generics<const N: usize>(_: impl Trait<N>)'
+pub async fn const_generics<const N: usize>(_: impl Trait<N>) {}
+
+// test that elided lifetimes are properly elided and not displayed as `'_`
+// regression test for #63037
+//@ has async_fn/fn.elided.html
+//@ has - '//pre[@class="rust item-decl"]' 'pub async fn elided(foo: &str) -> &str'
+pub async fn elided(foo: &str) -> &str { "" }
+// This should really be shown as written, but for implementation reasons it's difficult.
+// See `impl Clean for TyKind::Ref`.
+//@ has async_fn/fn.user_elided.html
+//@ has - '//pre[@class="rust item-decl"]' 'pub async fn user_elided(foo: &str) -> &str'
+pub async fn user_elided(foo: &'_ str) -> &str { "" }
+//@ has async_fn/fn.static_trait.html
+//@ has - '//pre[@class="rust item-decl"]' 'pub async fn static_trait(foo: &str) -> Box<dyn Bar>'
+pub async fn static_trait(foo: &str) -> Box<dyn Bar> { Box::new(()) }
+//@ has async_fn/fn.lifetime_for_trait.html
+//@ has - '//pre[@class="rust item-decl"]' "pub async fn lifetime_for_trait(foo: &str) -> Box<dyn Bar + '_>"
+pub async fn lifetime_for_trait(foo: &str) -> Box<dyn Bar + '_> { Box::new(()) }
+//@ has async_fn/fn.elided_in_input_trait.html
+//@ has - '//pre[@class="rust item-decl"]' "pub async fn elided_in_input_trait(t: impl Pattern<'_>)"
+pub async fn elided_in_input_trait(t: impl Pattern<'_>) {}
+
+struct AsyncFdReadyGuard<'a, T> { x: &'a T }
+
+impl Foo {
+    //@ has async_fn/struct.Foo.html
+    //@ has - '//*[@class="method"]' 'pub async fn complicated_lifetimes( &self, context: &impl Bar, ) -> impl Iterator<Item = &usize>'
+    pub async fn complicated_lifetimes(&self, context: &impl Bar) -> impl Iterator<Item = &usize> {
+        [0].iter()
+    }
+    // taken from `tokio` as an example of a method that was particularly bad before
+    //@ has - '//*[@class="method"]' "pub async fn readable<T>(&self) -> Result<AsyncFdReadyGuard<'_, T>, ()>"
+    pub async fn readable<T>(&self) -> Result<AsyncFdReadyGuard<'_, T>, ()> { Err(()) }
+    //@ has - '//*[@class="method"]' "pub async fn mut_self(&mut self)"
+    pub async fn mut_self(&mut self) {}
+}
+
+// test named lifetimes, just in case
+//@ has async_fn/fn.named.html
+//@ has - '//pre[@class="rust item-decl"]' "pub async fn named<'a, 'b>(foo: &'a str) -> &'b str"
+pub async fn named<'a, 'b>(foo: &'a str) -> &'b str { "" }
+//@ has async_fn/fn.named_trait.html
+//@ has - '//pre[@class="rust item-decl"]' "pub async fn named_trait<'a, 'b>(foo: impl Pattern<'a>) -> impl Pattern<'b>"
+pub async fn named_trait<'a, 'b>(foo: impl Pattern<'a>) -> impl Pattern<'b> {}
diff --git a/tests/rustdoc/async/async-move-doctest.rs b/tests/rustdoc/async/async-move-doctest.rs
new file mode 100644
index 00000000000..e18ec353533
--- /dev/null
+++ b/tests/rustdoc/async/async-move-doctest.rs
@@ -0,0 +1,12 @@
+//@ compile-flags:--test
+//@ edition:2018
+
+// Prior to setting the default edition for the doctest pre-parser,
+// this doctest would fail due to a fatal parsing error.
+// see https://github.com/rust-lang/rust/issues/59313
+
+//! ```
+//! fn foo() {
+//!     drop(async move {});
+//! }
+//! ```
diff --git a/tests/rustdoc/async/async-trait-sig.rs b/tests/rustdoc/async/async-trait-sig.rs
new file mode 100644
index 00000000000..be790f6ed7f
--- /dev/null
+++ b/tests/rustdoc/async/async-trait-sig.rs
@@ -0,0 +1,13 @@
+//@ edition:2021
+
+#![allow(incomplete_features)]
+
+pub trait Foo {
+    //@ has async_trait_sig/trait.Foo.html '//h4[@class="code-header"]' "async fn bar() -> i32"
+    async fn bar() -> i32;
+
+    //@ has async_trait_sig/trait.Foo.html '//h4[@class="code-header"]' "async fn baz() -> i32"
+    async fn baz() -> i32 {
+        1
+    }
+}
diff --git a/tests/rustdoc/async/async-trait.rs b/tests/rustdoc/async/async-trait.rs
new file mode 100644
index 00000000000..a6ee340e2dd
--- /dev/null
+++ b/tests/rustdoc/async/async-trait.rs
@@ -0,0 +1,15 @@
+//@ aux-build:async-trait-dep.rs
+//@ edition:2021
+
+#![allow(incomplete_features)]
+
+extern crate async_trait_dep;
+
+pub struct Oink {}
+
+//@ has 'async_trait/struct.Oink.html' '//h4[@class="code-header"]' "async fn woof()"
+impl async_trait_dep::Meow for Oink {
+    async fn woof() {
+        todo!()
+    }
+}
diff --git a/tests/rustdoc/async/auxiliary/async-trait-dep.rs b/tests/rustdoc/async/auxiliary/async-trait-dep.rs
new file mode 100644
index 00000000000..d89ec6d2998
--- /dev/null
+++ b/tests/rustdoc/async/auxiliary/async-trait-dep.rs
@@ -0,0 +1,8 @@
+//@ edition:2021
+
+#![allow(incomplete_features)]
+
+pub trait Meow {
+    /// Who's a good dog?
+    async fn woof();
+}