Don't swallow async cancel exceptions

Author: crtschin

ghcide-test/exe/ShakeRestartTests.hs

@@ -36,7 +36,7 @@ tests = testGroup "shake restart merging"
             merged = mergePendingRestart p1 (Just p2)
 
         pendingRestartReasons merged @?= ["r1", "r2"]
-        keys <- sequence $ pendingRestartActionBetweenSessions merged
+        keys <- sequence $ reverse $ pendingRestartActionBetweenSessions merged
         concat keys @?= [key2, key1]
 
     , testCase "RestartSlot coalescing" $ do

ghcide/src/Development/IDE/Core/Shake.hs

@@ -889,7 +889,9 @@ withRestartWorker ide@IdeState{..} action =
     withAsync (forever $
         processPendingRestart (shakeRecorder shakeExtras) ide
             `catch` \(e :: SomeException) ->
-                logWith (shakeRecorder shakeExtras) Error (LogRestartWorkerException e)) $
+                case fromException e of
+                  Just AsyncCancelled -> throwIO e
+                  _ -> logWith (shakeRecorder shakeExtras) Error (LogRestartWorkerException e)) $
         \_ -> action
 
 processPendingRestart :: Recorder (WithPriority Log) -> IdeState -> IO ()