add send test

Author: BennoLossin

tests/ui/field_projections/send.rs

@@ -0,0 +1,21 @@
+//@ revisions: old next
+//@ [next] compile-flags: -Znext-solver
+//@ run-pass
+#![feature(field_projections)]
+#![allow(incomplete_features)]
+use std::field::field_of;
+
+struct Foo {
+    field: u32,
+}
+struct Bar {
+    bar_field: u32,
+}
+unsafe impl Send for field_of!(Bar, bar_field) {}
+
+fn is_send<T: Send>() {}
+
+fn main() {
+    is_send::<field_of!(Bar, bar_field)>();
+    is_send::<field_of!(Foo, field)>();
+}