util.async: waiter: Remove restriction about wait() being called before done()

[prosody.git] / util / async.lua

diff --git a/util/async.lua b/util/async.lua
index afbaba5c62df52e434b40040118db5fe4de1af63..c81f8639b490b30905af66ac3428e70fe6eedbe0 100644 (file)
--- a/util/async.lua
+++ b/util/async.lua
@@ -28,14 +28,15 @@ local function waiter(num)
                error("Not running in an async context, see http://prosody.im/doc/developers/async");
        end
        num = num or 1;
+       local waiting;
        return function ()
+               if num == 0 then return; end -- already done
+               waiting = true;
                coroutine.yield("wait");
        end, function ()
                num = num - 1;
-               if num == 0 then
-                       if not runner_continue(thread) then
-                               error("done() called without wait()!");
-                       end
+               if num == 0 and waiting then
+                       runner_continue(thread);
                end
        end;
 end