Constrain base monad to MonadCatch

Let's try MonadThrow/MonadCatch. It looks nice at a first glance. The
monad transformer stack contains only the ReaderT, less lifts are
required. Exception subtyping is easier, the user can (and should)
define custom error types and throw them. And it is still possible to
use pure error handling, if someone doesn't like runtime exceptions or
need to run a query in a pure environment.

Fixes #42.

1 files changed, 10 insertions, 16 deletions

diff --git a/tests/Language/GraphQL/ExecuteSpec.hs b/tests/Language/GraphQL/ExecuteSpec.hs
index 7aab6c5..8fbb55b 100644
--- a/tests/Language/GraphQL/ExecuteSpec.hs
+++ b/tests/Language/GraphQL/ExecuteSpec.hs
@@ -7,11 +7,10 @@ module Language.GraphQL.ExecuteSpec
     ( spec
     ) where
 
+import Control.Exception (SomeException)
 import Data.Aeson ((.=))
 import qualified Data.Aeson as Aeson
 import Data.Conduit
-import Data.Either (fromRight)
-import Data.Functor.Identity (Identity(..))
 import Data.HashMap.Strict (HashMap)
 import qualified Data.HashMap.Strict as HashMap
 import Language.GraphQL.AST (Name)
@@ -23,14 +22,14 @@ import Language.GraphQL.Type.Out as Out
 import Test.Hspec (Spec, context, describe, it, shouldBe)
 import Text.Megaparsec (parse)
 
-schema :: Schema Identity
+schema :: Schema (Either SomeException)
 schema = Schema
     { query = queryType
     , mutation = Nothing
     , subscription = Just subscriptionType
     }
 
-queryType :: Out.ObjectType Identity
+queryType :: Out.ObjectType (Either SomeException)
 queryType = Out.ObjectType "Query" Nothing []
     $ HashMap.singleton "philosopher" 
     $ ValueResolver philosopherField
@@ -39,7 +38,7 @@ queryType = Out.ObjectType "Query" Nothing []
     philosopherField =
         Out.Field Nothing (Out.NonNullObjectType philosopherType) HashMap.empty
 
-philosopherType :: Out.ObjectType Identity
+philosopherType :: Out.ObjectType (Either SomeException)
 philosopherType = Out.ObjectType "Philosopher" Nothing []
     $ HashMap.fromList resolvers
   where
@@ -54,7 +53,7 @@ philosopherType = Out.ObjectType "Philosopher" Nothing []
         = Out.Field Nothing (Out.NonNullScalarType string) HashMap.empty
     lastNameResolver = pure $ Type.String "Nietzsche"
 
-subscriptionType :: Out.ObjectType Identity
+subscriptionType :: Out.ObjectType (Either SomeException)
 subscriptionType = Out.ObjectType "Subscription" Nothing []
     $ HashMap.singleton "newQuote"
     $ EventStreamResolver quoteField (pure $ Type.Object mempty)
@@ -63,7 +62,7 @@ subscriptionType = Out.ObjectType "Subscription" Nothing []
     quoteField =
         Out.Field Nothing (Out.NonNullObjectType quoteType) HashMap.empty
 
-quoteType :: Out.ObjectType Identity
+quoteType :: Out.ObjectType (Either SomeException)
 quoteType = Out.ObjectType "Quote" Nothing []
     $ HashMap.singleton "quote"
     $ ValueResolver quoteField
@@ -84,9 +83,7 @@ spec =
                         ]
                     expected = Response data'' mempty
                     execute' = execute schema Nothing (mempty :: HashMap Name Aeson.Value)
-                    actual = fromRight (singleError "")
-                        $ runIdentity
-                        $ either (pure . parseError) execute'
+                    Right (Right actual) = either (pure . parseError) execute'
                         $ parse document "" "{ philosopher { firstName surname } }"
                 in actual `shouldBe` expected
             it "merges selections" $
@@ -98,9 +95,7 @@ spec =
                         ]
                     expected = Response data'' mempty
                     execute' = execute schema Nothing (mempty :: HashMap Name Aeson.Value)
-                    actual = fromRight (singleError "")
-                        $ runIdentity
-                        $ either (pure . parseError) execute'
+                    Right (Right actual) = either (pure . parseError) execute'
                         $ parse document "" "{ philosopher { firstName } philosopher { lastName } }"
                 in actual `shouldBe` expected
         context "Subscription" $
@@ -112,8 +107,7 @@ spec =
                         ]
                     expected = Response data'' mempty
                     execute' = execute schema Nothing (mempty :: HashMap Name Aeson.Value)
-                    Left stream = runIdentity
-                        $ either (pure . parseError) execute'
+                    Right (Left stream) = either (pure . parseError) execute'
                         $ parse document "" "subscription { newQuote { quote } }"
-                    Just actual = runConduitPure $ stream .| await
+                    Right (Just actual) = runConduit $ stream .| await
                 in actual `shouldBe` expected