[#318] Fix roundtrip test for Key (#321)

Resolves #318

CHANGELOG.md

@@ -56,6 +56,8 @@ The changelog is available [on GitHub][2].
   Add tests on all kinds of `TomlDecodeError` with `decode` function.
 * [#313](https://github.com/kowainik/tomland/issues/313):
   Store `Key` in the `BiMapError` constructor of `TomlDecodeError`.
+* [#318](https://github.com/kowainik/tomland/issues/318):
+  Export a function for parsing TOML keys.
 * [#311](https://github.com/kowainik/tomland/issues/311):
   Reimplement custom `TomlState` instead of using `MaybeT` and `State`.
 

src/Toml/Codec/BiMap/Conversion.hs

@@ -98,7 +98,7 @@ import Text.Read (readEither)
 
 import Toml.Codec.BiMap (BiMap (..), TomlBiMap, TomlBiMapError (..), iso, mkAnyValueBiMap, prism,
                          tShow, wrongConstructor)
-import Toml.Parser.Key (keyP)
+import Toml.Parser (TomlParseError (..), parseKey)
 import Toml.Type.AnyValue (AnyValue (..), applyAsToAny, matchBool, matchDay, matchDouble,
                            matchHours, matchInteger, matchLocal, matchText, matchZoned,
                            mkMatchError, toMArray)
@@ -118,8 +118,6 @@ import qualified Data.Text.Encoding as T
 import qualified Data.Text.Lazy as TL
 import qualified Data.Text.Lazy.Encoding as TL
 
-import qualified Toml.Parser.Core as P (errorBundlePretty, parse)
-
 ----------------------------------------------------------------------------
 -- Primitive
 ----------------------------------------------------------------------------
@@ -564,7 +562,7 @@ _EnumBounded = _EnumBoundedText >>> _Text
 _KeyText :: TomlBiMap Key Text
 _KeyText = BiMap
     { forward = Right . prettyKey
-    , backward = textToKey
+    , backward = first (ArbitraryError . unTomlParseError) . parseKey
     }
 
 {- | Bidirectional converter between 'Key' and 'String'. Usually used
@@ -575,7 +573,7 @@ as an argument for 'Toml.Codec.Combinator.Map.tableMap'.
 _KeyString :: TomlBiMap Key String
 _KeyString = BiMap
     { forward = Right . T.unpack . prettyKey
-    , backward = textToKey . T.pack
+    , backward = first (ArbitraryError . unTomlParseError) . parseKey . T.pack
     }
 
 {- | Bidirectional converter between 'Key' and 'Int'. Usually used
@@ -586,14 +584,9 @@ as an argument for 'Toml.Codec.Combinator.Map.tableIntMap'.
 _KeyInt :: TomlBiMap Key Int
 _KeyInt = BiMap
     { forward = first (ArbitraryError . T.pack) . readEither . T.unpack . prettyKey
-    , backward = textToKey . tShow
+    , backward = first (ArbitraryError . unTomlParseError) . parseKey . tShow
     }
 
-textToKey :: Text -> Either TomlBiMapError Key
-textToKey t = case P.parse keyP "" t of
-    Left err  -> Left $ ArbitraryError $ T.pack $ P.errorBundlePretty err
-    Right key -> Right key
-
 ----------------------------------------------------------------------------
 -- General purpose bimaps
 ----------------------------------------------------------------------------

src/Toml/Parser.hs

@@ -11,15 +11,18 @@ Parser for text to TOML AST.
 module Toml.Parser
        ( TomlParseError (..)
        , parse
+       , parseKey
        ) where
 
 import Control.DeepSeq (NFData)
 import Data.Text (Text)
 import GHC.Generics (Generic)
 
 import Toml.Parser.Item (tomlP)
+import Toml.Parser.Key (keyP)
 import Toml.Parser.Validate (validateItems)
-import Toml.Type (TOML)
+import Toml.Type.Key (Key)
+import Toml.Type.TOML (TOML)
 
 import qualified Data.Text as T
 import qualified Toml.Parser.Core as P (errorBundlePretty, parse)
@@ -46,3 +49,12 @@ parse t = case P.parse tomlP "" t of
     Right items -> case validateItems items of
         Left err   -> Left $ TomlParseError $ T.pack $ show err
         Right toml -> Right toml
+
+{- | Parse TOML 'Key' from 'Text'.
+
+@since 1.3.0.0
+-}
+parseKey :: Text -> Either TomlParseError Key
+parseKey t = case P.parse keyP "" t of
+    Left err  -> Left $ TomlParseError $ T.pack $ P.errorBundlePretty err
+    Right key -> Right key

test/Test/Toml/Parser/Key.hs

@@ -44,3 +44,5 @@ keySpecs = describe "keyP" $ do
             parseKey "_"   "_"
             parseKey "__"  "__"
             parseKey "___" "___"
+        it "parses quotes" $
+            parseKey "\".\"" $ "\".\"" :|| []

test/Test/Toml/Type/Key.hs

@@ -2,15 +2,14 @@ module Test.Toml.Type.Key
     ( keySpec
     ) where
 
-import Data.String (IsString (..))
 import Hedgehog (forAll, tripping)
 import Test.Hspec (Arg, Expectation, Spec, SpecWith, describe, it, shouldBe)
 import Test.Hspec.Hedgehog (hedgehog)
 
 import Test.Toml.Gen (genKey)
 import Toml.Type.Key (KeysDiff (..), keysDiff)
 
-import qualified Data.Text as Text
+import qualified Toml.Parser as Parser
 import qualified Toml.Type.Printer as Printer
 
 
@@ -22,7 +21,7 @@ keySpec = describe "TOML Key" $ do
 keyRoundtripSpec :: SpecWith (Arg Expectation)
 keyRoundtripSpec = it "Key printing: fromString . prettyKey ≡ id" $ hedgehog $ do
     key <- forAll genKey
-    tripping key Printer.prettyKey (Just . fromString . Text.unpack)
+    tripping key Printer.prettyKey Parser.parseKey
 
 keysDiffSpec :: Spec
 keysDiffSpec = describe "Key difference" $ do