add tests

library/core/tests/future.rs

@@ -118,3 +118,11 @@ fn block_on(fut: impl Future) {
         }
     }
 }
+
+// just tests by whether or not this compiles
+fn _pending_impl_all_auto_traits<T>() {
+    use std::panic::{RefUnwindSafe, UnwindSafe};
+    fn all_auto_traits<T: Send + Sync + Unpin + UnwindSafe + RefUnwindSafe>() {}
+
+    all_auto_traits::<std::future::Pending<T>>();
+}

library/core/tests/hash/mod.rs

@@ -146,3 +146,11 @@ fn test_build_hasher_object_safe() {
 
     let _: &dyn BuildHasher<Hasher = DefaultHasher> = &RandomState::new();
 }
+
+// just tests by whether or not this compiles
+fn _build_hasher_default_impl_all_auto_traits<T>() {
+    use std::panic::{RefUnwindSafe, UnwindSafe};
+    fn all_auto_traits<T: Send + Sync + Unpin + UnwindSafe + RefUnwindSafe>() {}
+
+    all_auto_traits::<std::hash::BuildHasherDefault<T>>();
+}

library/core/tests/iter/traits/iterator.rs

@@ -496,3 +496,11 @@ fn test_collect() {
     let b: Vec<isize> = a.iter().cloned().collect();
     assert!(a == b);
 }
+
+// just tests by whether or not this compiles
+fn _empty_impl_all_auto_traits<T>() {
+    use std::panic::{RefUnwindSafe, UnwindSafe};
+    fn all_auto_traits<T: Send + Sync + Unpin + UnwindSafe + RefUnwindSafe>() {}
+
+    all_auto_traits::<std::iter::Empty<T>>();
+}