ouroboros-network-framework: drivers - code style

Reorder cases so they are more logical, i.e. first handling trailing
bytes from previous message, then bytes received from network followed
by `DecodeDone` and `DecodeFail`.

Author: coot

ouroboros-network-framework/src/Ouroboros/Network/Driver/Limits.hs

@@ -298,13 +298,6 @@ runDecoderWithLimit limit size Channel{recv} =
        -> DecodeStep bytes failure m (Identity a)
        -> m (Either (Maybe failure) (a, Maybe bytes))
 
-    go !sz !_ (DecodeDone (Identity x) trailing)
-      | let sz' = sz - maybe 0 size trailing
-      , sz' > limit = return (Left Nothing)
-      | otherwise   = return (Right (x, trailing))
-
-    go !_ !_ (DecodeFail failure) = return (Left (Just failure))
-
     go !sz trailing (DecodePartial k)
       | sz > limit = return (Left Nothing)
       | otherwise  = case trailing of
@@ -314,6 +307,13 @@ runDecoderWithLimit limit size Channel{recv} =
                        Just bs -> do let sz' = sz + size bs
                                      go sz' Nothing =<< k (Just bs)
 
+    go !sz !_ (DecodeDone (Identity x) trailing)
+      | let sz' = sz - maybe 0 size trailing
+      , sz' > limit = return (Left Nothing)
+      | otherwise   = return (Right (x, trailing))
+
+    go !_ !_ (DecodeFail failure) = return (Left (Just failure))
+
 
 runAnnotatedDecoderWithLimit
     :: forall m bytes failure a.
@@ -350,15 +350,10 @@ runAnnotatedDecoderWithLimit limit size Channel{recv} =
        -> DecodeStep bytes failure m (bytes -> a)
        -> m (Either (Maybe failure) (a, Maybe bytes))
 
-    go !bytes !sz !_ (DecodeDone f trailing)
-      | let sz' = sz - maybe 0 size trailing
-      , sz' > limit = return (Left Nothing)
-      | otherwise   = return (Right (f (mconcat $ reverse bytes), trailing))
-
-    go !_ !_ !_ (DecodeFail failure) = return (Left (Just failure))
-
-    go !_ !sz !_ DecodePartial {} | sz > limit =
-      return (Left Nothing)
+    go !bytes !sz (Just trailing) (DecodePartial k) = do
+      let sz' = sz + size trailing
+      step <- k (Just trailing)
+      go (trailing : bytes) sz' Nothing step
 
     go !bytes !sz Nothing (DecodePartial k) = do
       mbs <- recv
@@ -369,10 +364,15 @@ runAnnotatedDecoderWithLimit limit size Channel{recv} =
             Just bs -> bs : bytes)
          sz' Nothing step
 
-    go !bytes !sz (Just trailing) (DecodePartial k) = do
-      let sz' = sz + size trailing
-      step <- k (Just trailing)
-      go (trailing : bytes) sz' Nothing step
+    go !bytes !sz !_ (DecodeDone f trailing)
+      | let sz' = sz - maybe 0 size trailing
+      , sz' > limit = return (Left Nothing)
+      | otherwise   = return (Right (f (mconcat $ reverse bytes), trailing))
+
+    go !_ !_ !_ (DecodeFail failure) = return (Left (Just failure))
+
+    go !_ !sz !_ DecodePartial {} | sz > limit =
+      return (Left Nothing)
 
 
 -- | Run a peer with limits.

ouroboros-network-framework/src/Ouroboros/Network/Driver/Simple.hs

@@ -332,10 +332,10 @@ runAnnotatedDecoderWithChannel Channel{recv} bs0 = go (maybeToList bs0) bs0
        -> Maybe bytes
        -> DecodeStep bytes failure m (bytes -> a)
        -> m (Either failure (a, Maybe bytes))
-    go !bytes  _ (DecodeDone f trailing)        = return $ Right (f $ mconcat (reverse bytes), trailing)
-    go _bytes _ (DecodeFail failure)            = return (Left failure)
-    go !bytes Nothing         (DecodePartial k) = recv >>= \bs -> k bs >>= go (maybe bytes (: bytes) bs) Nothing
     go !bytes (Just trailing) (DecodePartial k) = k (Just trailing) >>= go (trailing : bytes) Nothing
+    go !bytes Nothing         (DecodePartial k) = recv >>= \bs -> k bs >>= go (maybe bytes (: bytes) bs) Nothing
+    go !bytes _ (DecodeDone f trailing)         = return $ Right (f $ mconcat (reverse bytes), trailing)
+    go _bytes _ (DecodeFail failure)            = return (Left failure)
 
 
 data Role = Client | Server