Implicit return working for async proc (#20933)

* Implicit return working for asyncdispatch proc

Closes #11558

* Test case

* Test that return value is actually used

* Update tests/async/t11558.nim

Co-authored-by: Andreas Rumpf <rumpf_a@web.de>

1 files changed, 13 insertions, 0 deletions

diff --git a/tests/async/t11558.nim b/tests/async/t11558.nim
new file mode 100644
index 000000000..99961e7b6
--- /dev/null
+++ b/tests/async/t11558.nim
@@ -0,0 +1,13 @@
+discard """
+output: "Hello\n9"
+"""
+import std/asyncdispatch
+
+proc foo(): Future[string] {.async.} =
+  "Hello"
+
+proc bar(): Future[int] {.async.} =
+  result = 9
+
+echo waitFor foo()
+echo waitFor bar()