From 46b6f2d08f6d3ab7223e36b9055e490e40ef9602 Mon Sep 17 00:00:00 2001
From: Francesco Gazzetta <fgaz@fgaz.me>
Date: Mon, 14 Mar 2022 18:13:27 +0100
Subject: [PATCH] Fix null truncating lists and maps

For now we error out, since adding UCLNull will be a breaking change
---
 src/Data/UCL.hs  | 25 +++++++++++--------------
 test/ucl-test.hs |  2 ++
 2 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/src/Data/UCL.hs b/src/Data/UCL.hs
index f1961ea..6abadc8 100644
--- a/src/Data/UCL.hs
+++ b/src/Data/UCL.hs
@@ -11,7 +11,7 @@ module Data.UCL
 import Foreign.C
   ( CUInt(..), CInt(..), CSize(..), CDouble(..), CString, CStringLen
   , withCString, withCStringLen, peekCString )
-import Foreign.Ptr (Ptr, FunPtr)
+import Foreign.Ptr (Ptr, FunPtr, nullPtr)
 import Foreign.ForeignPtr
 import qualified Data.Text.Foreign as TF
 import Data.Text (Text)
@@ -172,6 +172,7 @@ foreignToUCL obj = do
     UCL_TIME     -> UCLTime . realToFrac <$> ucl_object_todouble obj
     -- TODO use Left instead of error
     UCL_USERDATA -> error "Userdata object"
+    -- TODO add UCLNull
     UCL_NULL     -> error "Null object"
     _            -> error "Unknown Type"
 
@@ -184,14 +185,12 @@ uclObjectToMap o = do
       -- NOTE: the reference count of the returned object is not increased,
       -- so we don't use ForeignPtr
       obj <- withForeignPtr it (`ucl_object_iterate_safe` True)
-      ty <- ucl_object_type obj
-      case ty of
-        -- FIXME this is not how we check for end of object
-        UCL_NULL -> pure m
-        _        -> do
-                      k <- ucl_object_key obj >>= peekCStringText
-                      v <- foreignToUCL obj
-                      go it $ Map.insert k v m
+      if obj == nullPtr
+      then pure m
+      else do
+        k <- ucl_object_key obj >>= peekCStringText
+        v <- foreignToUCL obj
+        go it $ Map.insert k v m
 
 uclArrayToList :: Ptr UCLObject -> IO [UCL]
 uclArrayToList o = do
@@ -202,8 +201,6 @@ uclArrayToList o = do
       -- NOTE: the reference count of the returned object is not increased
       -- so we don't use ForeignPtr
       obj <- withForeignPtr it (`ucl_object_iterate_safe` True)
-      ty <- ucl_object_type obj
-      case ty of
-        -- FIXME this is not how we check for end of object
-        UCL_NULL -> pure []
-        _        -> (:) <$> foreignToUCL obj <*> go it
+      if obj == nullPtr
+      then pure []
+      else (:) <$> foreignToUCL obj <*> go it
diff --git a/test/ucl-test.hs b/test/ucl-test.hs
index 5476034..0b55b7a 100644
--- a/test/ucl-test.hs
+++ b/test/ucl-test.hs
@@ -18,6 +18,8 @@ main = do
           , ("3",UCLBool True)
           , ("a",UCLArray [UCLInt 12, UCLInt 34, UCLInt 56])
           , ("b",UCLText "foo")]))
+    -- TODO add UCLNull
+    --, ("0: false, 1: null, 2: true", UCLMap $ fromList [("0", UCLBool False), ("1", UCLNull), ("2", UCLBool True)])
     ]
   unless success exitFailure
 
-- 
2.45.2