Remaining nullary continuation fixes for folly

Summary: then to thenValue to remove calls to deprecated functions.

Reviewed By: yfeldblum

Differential Revision: D10366311

fbshipit-source-id: 99c4cd8bcfa2d9db80c2d8eb22300d92609a36fc

folly/experimental/coro/Utils.h

@@ -91,8 +91,10 @@ class TimedWaitAwaitable {
   bool await_suspend(std::experimental::coroutine_handle<> ch) {
     auto sharedState = std::make_shared<SharedState>(ch, storage_);
     waitAndNotify(std::move(awaitable_), sharedState).detach();
-    futures::sleep(duration_).then(
-        [sharedState = std::move(sharedState)] { sharedState->setTimeout(); });
+    futures::sleep(duration_).thenValue(
+        [sharedState = std::move(sharedState)](Unit) {
+          sharedState->setTimeout();
+        });
     return true;
   }
 

folly/experimental/coro/test/CoroTest.cpp

@@ -197,7 +197,9 @@ TEST(Coro, CurrentExecutor) {
 
 coro::Task<void> taskTimedWait() {
   auto fastFuture =
-      futures::sleep(std::chrono::milliseconds{50}).then([] { return 42; });
+      futures::sleep(std::chrono::milliseconds{50}).thenValue([](Unit) {
+        return 42;
+      });
   auto fastResult = co_await coro::timed_wait(
       std::move(fastFuture), std::chrono::milliseconds{100});
   EXPECT_TRUE(fastResult);
@@ -207,7 +209,8 @@ coro::Task<void> taskTimedWait() {
     ExpectedException() : std::runtime_error("ExpectedException") {}
   };
 
-  auto throwingFuture = futures::sleep(std::chrono::milliseconds{50}).then([] {
+  auto throwingFuture =
+      futures::sleep(std::chrono::milliseconds{50}).thenValue([](Unit) {
         throw ExpectedException();
       });
   EXPECT_THROW(
@@ -216,7 +219,9 @@ coro::Task<void> taskTimedWait() {
       ExpectedException);
 
   auto slowFuture =
-      futures::sleep(std::chrono::milliseconds{200}).then([] { return 42; });
+      futures::sleep(std::chrono::milliseconds{200}).thenValue([](Unit) {
+        return 42;
+      });
   auto slowResult = co_await coro::timed_wait(
       std::move(slowFuture), std::chrono::milliseconds{100});
   EXPECT_FALSE(slowResult);