Fix disposing an empty resource manager after a delay

src/Quasar/Disposable.hs

@@ -255,19 +255,20 @@ collectGarbage resourceManager = go >> traceIO "gc: completed"
     go :: IO ()
     go = do
       traceIO "gc: go"
-      (snapshot, disposing) <- atomically $ do
-        snapshot <- readTVar entriesVar'
-        disposing <- readTVar (disposingVar resourceManager)
-        pure (snapshot, disposing)
+      snapshot <- atomically $ readTVar entriesVar'
 
-      let listChanged = simpleAwaitable $ do
+      let listChanged = simpleAwaitable do
             newLength <- Seq.length <$> readTVar entriesVar'
             when (newLength == Seq.length snapshot) retry
 
+          isDisposing = simpleAwaitable do
+            disposing <- readTVar (disposingVar resourceManager)
+            unless disposing retry
+
       -- Wait for any entry to complete or until a new entry is added
       let awaitables = (toAwaitable <$> toList snapshot)
       awaitIO if Quasar.Prelude.null awaitables
-        then unless disposing $ listChanged
+        then awaitAny2 listChanged isDisposing
         else awaitAny (listChanged :| awaitables)
 
       traceIO "gc: change detected"

test/Quasar/AwaitableSpec.hs

@@ -30,7 +30,7 @@ spec = parallel $ do
 
       awaitIO avar
 
-    it "can be awaited and completed later" $ do
+    it "can be awaited when completed asynchronously" $ do
       avar <- newAsyncVar :: IO (AsyncVar ())
       void $ forkIO $ do
         threadDelay 100000
@@ -86,7 +86,7 @@ spec = parallel $ do
       putAsyncVar_ avar ()
       withDefaultAsyncManager (id <$> await avar)
 
-    xit "can fmap the result of an async that is completed later" $ do
+    it "can fmap the result of an async that is completed later" $ do
       avar <- newAsyncVar :: IO (AsyncVar ())
       void $ forkIO $ do
         threadDelay 100000
@@ -98,7 +98,7 @@ spec = parallel $ do
       putAsyncVar_ avar ()
       withDefaultAsyncManager (await avar >>= pure)
 
-    xit "can bind the result of an async that is completed later" $ do
+    it "can bind the result of an async that is completed later" $ do
       avar <- newAsyncVar :: IO (AsyncVar ())
       void $ forkIO $ do
         threadDelay 100000