HsYAML 0.2 support

HsYAML-aeson.cabal

@@ -30,7 +30,7 @@ source-repository head
 library
   exposed-modules: Data.YAML.Aeson
   build-depends:
-    , HsYAML      ^>= 0.1.1.0
+    , HsYAML      ^>= 0.2
     , aeson       ^>= 1.4.0.0
     , base         >= 4.5 && < 4.13
     , bytestring  ^>= 0.9.2.1 || ^>= 0.10.0.2

src/Data/YAML/Aeson.hs

@@ -19,7 +19,7 @@
 module Data.YAML.Aeson
     ( -- * Parsing YAML using JSON models
       -- ** High-level parsing/decoding via 'FromJSON' instances
-      decode1
+      Data.YAML.Aeson.decode1
     , decode1'
       -- ** Parsing into JSON AST ('J.Value')
     , decodeValue
@@ -35,6 +35,7 @@ import qualified Data.ByteString.Lazy   as BS.L
 import           Data.Text              (Text)
 import qualified Data.Vector            as V
 import           Data.YAML              as Y
+import           Data.YAML.Event        (Pos)
 
 -- | Parse a single YAML document using the 'coreSchemaResolver' and decode to Haskell types using 'FromJSON' instances.
 --
@@ -46,9 +47,9 @@ import           Data.YAML              as Y
 -- decoder configuration.
 --
 decode1 :: FromJSON v => BS.L.ByteString -> Either String v
-decode1 bs = do
-  vs <- decodeValue bs
-  case vs of
+decode1 bs = case decodeValue bs of
+  Left (_ ,err) -> Left err
+  Right vs -> case vs of
     [] -> Left "No documents found in YAML stream"
     (_:_:_) -> Left "Multiple documents encountered in YAML stream"
     [v1] -> do
@@ -58,9 +59,9 @@ decode1 bs = do
 
 -- | Variant of 'decode1' allowing for customization. See 'decodeValue'' for documentation of parameters.
 decode1' :: FromJSON v => SchemaResolver -> (J.Value -> Either String Text) -> BS.L.ByteString -> Either String v
-decode1' schema keyconv bs = do
-  vs <- decodeValue' schema keyconv bs
-  case vs of
+decode1' schema keyconv bs = case decodeValue' schema keyconv bs of
+  Left (_ ,err) -> Left err
+  Right vs -> case vs of 
     [] -> Left "No documents found in YAML stream"
     (_:_:_) -> Left "Multiple documents encountered in YAML stream"
     [v1] -> do
@@ -83,7 +84,7 @@ decode1' schema keyconv bs = do
 -- which performs no conversion and will fail when encountering YAML
 -- Scalars that have not been resolved to a text Scalar (according to
 -- the respective YAML schema resolver).
-decodeValue :: BS.L.ByteString -> Either String [J.Value]
+decodeValue :: BS.L.ByteString -> Either (Pos, String) [J.Value]
 decodeValue = decodeValue' coreSchemaResolver identityKeyConv
   where
     identityKeyConv :: J.Value -> Either String Text
@@ -103,15 +104,15 @@ decodeValue' :: SchemaResolver  -- ^ YAML Schema resolver to use
                 -- ^ JSON object key conversion function. This operates on the YAML node as resolved by the 'SchemaResolver' and subsequently converted into a JSON Value according to the 'scalarToValue' conversion. See 'decodeValue' documentation for an example.
 
              -> BS.L.ByteString -- ^ YAML document to parse
-             -> Either String [J.Value]
+             -> Either (Pos, String) [J.Value]
 decodeValue' SchemaResolver{..} keyconv bs0
     = runIdentity (decodeLoader failsafeLoader bs0)
   where
-    failsafeLoader = Loader { yScalar   = \t s v -> pure $! schemaResolverScalar t s v >>= mkScl
-                            , ySequence = \t vs  -> pure $! schemaResolverSequence t >>= \_ -> mkArr vs
-                            , yMapping  = \t kvs -> pure $! schemaResolverMapping  t >>= \_ -> mkObj kvs
-                            , yAlias    = \_ c n -> pure $! if c then Left "cycle detected" else Right n
-                            , yAnchor   = \_ n   -> Ap.pure $! Right $! n
+    failsafeLoader = Loader { yScalar   = \t s v _ -> pure $! schemaResolverScalar t s v >>= mkScl
+                            , ySequence = \t vs _  -> pure $! schemaResolverSequence t >>= \_ -> mkArr vs
+                            , yMapping  = \t kvs _  -> pure $! schemaResolverMapping  t >>= \_ -> mkObj kvs
+                            , yAlias    = \_ c n _ -> pure $! if c then Left "cycle detected" else Right n
+                            , yAnchor   = \_ n _   -> Ap.pure $! Right $! n
                             }
 
     mkObj :: [(J.Value, J.Value)] -> Either String J.Value