1 files changed, 151 insertions, 0 deletions
diff --git a/third_party/rust/pin-project/tests/project_ref.rs b/third_party/rust/pin-project/tests/project_ref.rs
new file mode 100644
index 0000000000..a90e016100
--- /dev/null
+++ b/third_party/rust/pin-project/tests/project_ref.rs
@@ -0,0 +1,151 @@
+#![warn(unsafe_code)]
+#![warn(rust_2018_idioms, single_use_lifetimes)]
+#![allow(dead_code)]
+
+use pin_project::{pin_project, project_ref};
+use std::pin::Pin;
+
+#[project_ref] // Nightly does not need a dummy attribute to the function.
+#[test]
+fn project_stmt_expr() {
+    // struct
+
+    #[pin_project]
+    struct Foo<T, U> {
+        #[pin]
+        field1: T,
+        field2: U,
+    }
+
+    let foo = Foo { field1: 1, field2: 2 };
+
+    #[project_ref]
+    let Foo { field1, field2 } = Pin::new(&foo).project_ref();
+
+    let x: Pin<&i32> = field1;
+    assert_eq!(*x, 1);
+
+    let y: &i32 = field2;
+    assert_eq!(*y, 2);
+
+    // tuple struct
+
+    #[pin_project]
+    struct Bar<T, U>(#[pin] T, U);
+
+    let bar = Bar(1, 2);
+
+    #[project_ref]
+    let Bar(x, y) = Pin::new(&bar).project_ref();
+
+    let x: Pin<&i32> = x;
+    assert_eq!(*x, 1);
+
+    let y: &i32 = y;
+    assert_eq!(*y, 2);
+
+    // enum
+
+    #[pin_project]
+    enum Baz<A, B, C, D> {
+        Variant1(#[pin] A, B),
+        Variant2 {
+            #[pin]
+            field1: C,
+            field2: D,
+        },
+        None,
+    }
+
+    let baz = Baz::Variant1(1, 2);
+
+    let baz = Pin::new(&baz).project_ref();
+
+    #[project_ref]
+    match &baz {
+        Baz::Variant1(x, y) => {
+            let x: &Pin<&i32> = x;
+            assert_eq!(**x, 1);
+
+            let y: &&i32 = y;
+            assert_eq!(**y, 2);
+        }
+        Baz::Variant2 { field1, field2 } => {
+            let _x: &Pin<&i32> = field1;
+            let _y: &&i32 = field2;
+        }
+        Baz::None => {}
+    }
+
+    #[project_ref]
+    let val = match &baz {
+        Baz::Variant1(_, _) => true,
+        Baz::Variant2 { .. } => false,
+        Baz::None => false,
+    };
+    assert_eq!(val, true);
+}
+
+#[test]
+fn project_impl() {
+    #[pin_project]
+    struct HasGenerics<T, U> {
+        #[pin]
+        field1: T,
+        field2: U,
+    }
+
+    #[project_ref]
+    impl<T, U> HasGenerics<T, U> {
+        fn a(self) {
+            let Self { field1, field2 } = self;
+
+            let _x: Pin<&T> = field1;
+            let _y: &U = field2;
+        }
+    }
+
+    #[pin_project]
+    struct NoneGenerics {
+        #[pin]
+        field1: i32,
+        field2: u32,
+    }
+
+    #[project_ref]
+    impl NoneGenerics {}
+
+    #[pin_project]
+    struct HasLifetimes<'a, T, U> {
+        #[pin]
+        field1: &'a mut T,
+        field2: U,
+    }
+
+    #[project_ref]
+    impl<T, U> HasLifetimes<'_, T, U> {}
+
+    #[pin_project]
+    struct HasOverlappingLifetimes<'pin, T, U> {
+        #[pin]
+        field1: &'pin mut T,
+        field2: U,
+    }
+
+    #[allow(single_use_lifetimes)]
+    #[project_ref]
+    impl<'pin, T, U> HasOverlappingLifetimes<'pin, T, U> {}
+
+    #[pin_project]
+    struct HasOverlappingLifetimes2<T, U> {
+        #[pin]
+        field1: T,
+        field2: U,
+    }
+
+    #[allow(single_use_lifetimes)]
+    #[project_ref]
+    impl<T, U> HasOverlappingLifetimes2<T, U> {
+        fn foo<'pin>(&'pin self) {}
+    }
+}