Move Execute.Directive to Type.Directive

Just to roughly follow the structure of the reference implementation.

src/Language/GraphQL/Execute/Directive.hs

@@ -1,50 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-
-module Language.GraphQL.Execute.Directive
-    ( selection
-    ) where
-
-import qualified Data.HashMap.Strict as HashMap
-import Language.GraphQL.AST.Core
-
--- | Directive processing status.
-data Status
-    = Skip -- ^ Skip the selection and stop directive processing
-    | Include Directive -- ^ The directive was processed, try other handlers
-    | Continue Directive -- ^ Directive handler mismatch, try other handlers
-
--- | Takes a list of directives, handles supported directives and excludes them
---   from the result. If the selection should be skipped, returns 'Nothing'.
-selection :: [Directive] -> Maybe [Directive]
-selection = foldr go (Just [])
-  where
-    go directive' directives' =
-        case (skip . include) (Continue directive') of
-            (Include _) -> directives'
-            Skip -> Nothing
-            (Continue x) -> (x :) <$> directives'
-
-handle :: (Directive -> Status) -> Status -> Status
-handle _ Skip = Skip
-handle handler (Continue directive) = handler directive
-handle handler (Include directive) = handler directive
-
--- * Directive implementations
-
-skip :: Status -> Status
-skip = handle skip'
-  where
-    skip' directive'@(Directive "skip" (Arguments arguments)) =
-        case HashMap.lookup "if" arguments of
-            (Just (Boolean True)) -> Skip
-            _ -> Include directive'
-    skip' directive' = Continue directive'
-
-include :: Status -> Status
-include = handle include'
-  where
-    include' directive'@(Directive "include" (Arguments arguments)) =
-        case HashMap.lookup "if" arguments of
-            (Just (Boolean True)) -> Include directive'
-            _ -> Skip
-    include' directive' = Continue directive'

src/Language/GraphQL/Execute/Transform.hs

@@ -19,8 +19,8 @@ import qualified Data.List.NonEmpty as NonEmpty
 import Data.Sequence (Seq, (<|), (><))
 import qualified Language.GraphQL.AST as Full
 import qualified Language.GraphQL.AST.Core as Core
-import qualified Language.GraphQL.Execute.Directive as Directive
 import qualified Language.GraphQL.Schema as Schema
+import qualified Language.GraphQL.Type.Directive as Directive
 
 -- | Associates a fragment name with a list of 'Core.Field's.
 data Replacement = Replacement