sync: move CancellationToken tests (#2477)

In preparation of work on `CancellationToken` internals, the tests are
moved into `tests/` and are updated to not depend on internals.

1 files changed, 10 insertions, 0 deletions

diff --git a/tokio/src/macros/cfg.rs b/tokio/src/macros/cfg.rs
index 85f95cbd..618b8f66 100644
--- a/tokio/src/macros/cfg.rs
+++ b/tokio/src/macros/cfg.rs
@@ -353,3 +353,13 @@ macro_rules! cfg_uds {
         )*
     }
 }
+
+macro_rules! cfg_unstable {
+    ($($item:item)*) => {
+        $(
+            #[cfg(tokio_unstable)]
+            #[cfg_attr(docsrs, doc(cfg(tokio_unstable)))]
+            $item
+        )*
+    }
+}