FutureVar[T] parameters are now completed automatically.

tests/async/tfuturevar.nim

@@ -0,0 +1,47 @@
+import asyncdispatch
+
+proc completeOnReturn(fut: FutureVar[string], x: bool) {.async.} =
+  if x:
+    fut.mget() = ""
+    fut.mget.add("foobar")
+    return
+
+proc completeOnImplicitReturn(fut: FutureVar[string], x: bool) {.async.} =
+  if x:
+    fut.mget() = ""
+    fut.mget.add("foobar")
+
+proc failureTest(fut: FutureVar[string], x: bool) {.async.} =
+  if x:
+    raise newException(Exception, "Test")
+
+proc manualComplete(fut: FutureVar[string], x: bool) {.async.} =
+  if x:
+    fut.mget() = "Hello World"
+    fut.complete()
+    return
+
+proc main() {.async.} =
+  var fut: FutureVar[string]
+
+  fut = newFutureVar[string]()
+  await completeOnReturn(fut, true)
+  doAssert(fut.read() == "foobar")
+
+  fut = newFutureVar[string]()
+  await completeOnImplicitReturn(fut, true)
+  doAssert(fut.read() == "foobar")
+
+  fut = newFutureVar[string]()
+  let retFut = failureTest(fut, true)
+  yield retFut
+  doAssert(fut.read().isNil)
+  doAssert(fut.finished)
+
+  fut = newFutureVar[string]()
+  await manualComplete(fut, true)
+  doAssert(fut.read() == "Hello World")
+
+
+waitFor main()
+