implemented decodeUTF8

src/Data/CSV/Slurp.hs

@@ -35,6 +35,7 @@ import Conduit (ConduitT, mapC, (.|))
 import qualified Data.ByteString as BS
 import Data.Maybe (fromMaybe)
 import qualified Data.Text as T
+import Data.Text.Encoding (decodeUtf8')
 
 -- | decode the rows from a stream of ByteStrings
 decodeRows :: Monad m => ConduitT BS.ByteString [T.Text] m ()
@@ -46,6 +47,8 @@ decodeRawRows = return ()
 
 -- | decode a raw ByteString into Text (if possible)
 decodeUTF8 :: BS.ByteString -> Maybe T.Text
-decodeUTF8 = const Nothing
+decodeUTF8 bs = case decodeUtf8' bs of
+  Left _    -> Nothing
+  Right txt -> Just txt
 
 --jl

test/Data/CSV/SlurpSpec.hs

@@ -24,13 +24,14 @@ module Data.CSV.SlurpSpec (spec) where
 
 import Conduit (runConduit, (.|))
 import Data.Conduit.List (consume, sourceList)
-import Test.Hspec (Spec, context, describe, shouldBe, xit)
+import Test.Hspec (Spec, context, describe, it, shouldBe, xit)
 
 import Data.CSV.Slurp
 
 spec :: Spec
-spec = describe "Data.CSV.Slurp"
+spec = describe "Data.CSV.Slurp" $ do
   decodeRowsSpec
+  decodeUTF8Spec
 
 decodeRowsSpec :: Spec
 decodeRowsSpec = describe "decodeRows" $ mapM_
@@ -59,4 +60,18 @@ decodeRowsSpec = describe "decodeRows" $ mapM_
     invalidIn = ["\"a"]
     validRes  = [["foo", "bar"], ["baz", "quux"]]
 
+decodeUTF8Spec :: Spec
+decodeUTF8Spec = describe "decodeUTF8" $ mapM_
+  ( \(label, input, expected) -> context label $
+    it ("should be " ++ show expected) $
+      decodeUTF8 input `shouldBe` expected
+  )
+
+  --  label,          input,      expected
+  [ ( "plain ASCII",  "hello",    Just "hello" )
+  , ( "valid UTF8",   "\xc3\xa9", Just "é"     )
+  , ( "invalid UTF8", "\xff",     Nothing      )
+  , ( "blank",        "",         Just ""      )
+  ]
+
 --jl