Support aeson >= 2 (#313)

* Support aeson >= 2

* Add changelog entry for aeson 2.0

* Adapt tests to aeson >= 2

ChangeLog.md

@@ -1,5 +1,10 @@
 # ChangeLog hie-bios
 
+## TBD - 0.8.0
+
+* Support aeson >= 2.0. [#313](https://github.com/haskell/hie-bios/pull/313)
+* Remove CradleOpt Type [#293](https://github.com/haskell/hie-bios/pull/293)
+
 ## 2021-08-30 - 0.7.6
 
 * Don't look for NIX_GHC_LIBDIR as it is redundant [#294](https://github.com/mpickering/hie-bios/pull/294)

hie-bios.cabal

@@ -146,7 +146,7 @@ Library
   autogen-modules:      Paths_hie_bios
   Build-Depends:
                         base                 >= 4.8 && < 5,
-                        aeson                >= 1.4.5 && < 2,
+                        aeson                >= 1.4.5 && < 2.1,
                         base16-bytestring    >= 0.1.1 && < 1.1,
                         bytestring           >= 0.10.8 && < 0.12,
                         deepseq              >= 1.4.3 && < 1.5,
@@ -191,6 +191,7 @@ test-suite parser-tests
   default-language: Haskell2010
   build-depends:
       base,
+      aeson,
       filepath,
       hie-bios,
       hspec-expectations,

src/HIE/Bios/Config.hs

@@ -5,6 +5,7 @@
 {-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE ViewPatterns #-}
 {-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE CPP #-}
 -- | Logic and datatypes for parsing @hie.yaml@ files.
 module HIE.Bios.Config(
     readConfig,
@@ -24,14 +25,36 @@ module HIE.Bios.Config(
 import Control.Exception
 import qualified Data.Text as T
 import qualified Data.Vector as V
+#if MIN_VERSION_aeson(2,0,0)
+import           Data.Aeson.Key (fromText)
+import           Data.Aeson.KeyMap (KeyMap)
+import qualified Data.Aeson.KeyMap as Map
+#else
 import qualified Data.HashMap.Strict as Map
+#endif
 import           Data.Maybe (mapMaybe)
 import           Data.Monoid (Last(..))
 import           Data.Foldable (foldrM)
 import           Data.Aeson (JSONPath)
 import           Data.Yaml
 import           Data.Yaml.Internal (Warning(..))
 
+
+#if !MIN_VERSION_aeson(2,0,0)
+-- | Backwards compatible type-def for Key
+-- This used to be just a Text, but since aeson >= 2
+-- this is an opaque datatype.
+type Key = T.Text
+-- | Backwards compatible type-def for KeyMap
+-- This used to be just a HashMap, but since aeson >= 2
+-- this is an opaque datatype.
+type KeyMap v = Map.HashMap T.Text v
+
+-- | Create a Key from a Text.
+fromText :: T.Text -> Key
+fromText = id
+#endif
+
 -- | Configuration that can be used to load a 'Cradle'.
 -- A configuration has roughly the following form:
 --
@@ -149,7 +172,7 @@ parseSingleOrMultiple
   :: Monoid x
   => (x -> CradleType a)
   -> (x -> [(FilePath, x)] -> CradleType a)
-  -> (Map.HashMap T.Text Value -> Parser x)
+  -> (KeyMap Value -> Parser x)
   -> Value
   -> Parser (CradleType a)
 parseSingleOrMultiple single multiple parse = doParse where
@@ -224,7 +247,7 @@ parseBios (Object x) =
         exclusive l Nothing = l
         exclusive Nothing r = r
         stringTypeFromMap :: (String -> t) -> T.Text -> Maybe t
-        stringTypeFromMap constructor name = constructor <$> (intoString =<< Map.lookup name x)
+        stringTypeFromMap constructor name = constructor <$> (intoString =<< Map.lookup (fromText name) x)
         intoString :: Value -> Maybe String
         intoString (String s) = Just (T.unpack s)
         intoString _ = Nothing

tests/ParserTests.hs

@@ -1,14 +1,20 @@
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE CPP #-}
 module Main where
 
 import Test.Hspec.Expectations
 import Test.Tasty
 import Test.Tasty.HUnit
 import HIE.Bios.Config
+#if MIN_VERSION_aeson(2,0,0)
+import           Data.Aeson.Key ( Key )
+import qualified Data.Aeson.KeyMap as Map
+#else
 import qualified Data.HashMap.Strict as Map
+import qualified Data.Text as T
+#endif
 import Data.Void
 import Data.Yaml
-import qualified Data.Text as T
 import System.FilePath
 import Control.Applicative ( (<|>) )
 import Control.Exception
@@ -120,11 +126,19 @@ instance FromJSON CabalHelper where
 
   parseJSON _ = fail "Not a valid cabal-helper specification"
 
-simpleCabalHelperYaml :: T.Text -> Value
+simpleCabalHelperYaml :: Key -> Value
 simpleCabalHelperYaml tool =
   object
     [ ( "cabal-helper", object
         [ (tool, Null)
         ]
       )
     ]
+
+-- ------------------------------------------------------------------
+-- Helper functions to support aeson < 2
+-- ------------------------------------------------------------------
+
+#if !MIN_VERSION_aeson(2,0,0)
+type Key = T.Text
+#endif