WIP

rhine/test/Clock/Except.hs

@@ -0,0 +1,63 @@
+{-# LANGUAGE Arrows #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+module Clock.Except where
+
+-- base
+import GHC.IO.Handle (hDuplicateTo)
+import System.IO (IOMode (ReadMode), stdin, withFile)
+
+-- transformers
+import Control.Monad.Trans.Writer.CPS
+
+-- text
+import Data.Text (Text)
+
+-- tasty
+import Test.Tasty (testGroup)
+
+-- tasty-hunit
+import Test.Tasty.HUnit (testCase, (@?))
+
+-- rhine
+import FRP.Rhine
+import FRP.Rhine.Clock.Except (CatchClock (CatchClock), ExceptClock (ExceptClock))
+import Paths_rhine
+import System.IO.Error (isEOFError)
+
+type E = ExceptT IOError IO
+type WT = WriterT [Text]
+type M = WT E
+type EClock = ExceptClock StdinClock IOError
+
+
+type TestClock =
+  LiftClock
+    E
+    WT
+    ( CatchClock
+        EClock
+        IOError
+        EClock
+        IOError
+    )
+
+-- FIXME also need to test the other branch of CatchClock
+testClock :: TestClock
+testClock = liftClock $ CatchClock (ExceptClock StdinClock) $ const $ Right $ ExceptClock StdinClock
+
+clsf :: ClSF M TestClock () ()
+clsf = proc () -> do
+  tag <- tagS -< ()
+  arrMCl tell -< either (const ["weird"]) pure tag
+
+tests =
+  testGroup
+    "ExceptClock"
+    [ testCase "Outputs the exception on EOF" $ do
+        testdataFile <- getDataFileName "test/assets/testdata.txt"
+        withFile testdataFile ReadMode $ \h -> do
+          hDuplicateTo h stdin
+          Left result <- runExceptT $ runWriterT $ flow $ clsf @@ testClock
+          isEOFError result @? "It's an EOF error"
+    ]