Add tests for instance derivation

tests/Language/GraphQL/ClassSpec.hs

@@ -29,6 +29,25 @@ data TwoFieldRecord = TwoFieldRecord
 $(deriveToGraphQL ''TwoFieldRecord)
 $(deriveFromGraphQL ''TwoFieldRecord)
 
+data TwoVariantUnion
+    = FirstVariantUnion TwoFieldRecord
+    | SecondVariantUnion TwoFieldRecord
+    deriving (Eq, Show)
+
+$(deriveToGraphQL ''TwoVariantUnion)
+
+newtype NewTypeRecord = NewTypeRecord { newTypeField :: Int }
+    deriving (Eq, Show)
+
+$(deriveToGraphQL ''NewTypeRecord)
+$(deriveFromGraphQL ''NewTypeRecord)
+
+data TwoFieldEnum = TWO_FIELD_ENUM_1 | TWO_FIELD_ENUM_2
+    deriving (Eq, Show)
+
+$(deriveToGraphQL ''TwoFieldEnum)
+$(deriveFromGraphQL ''TwoFieldEnum)
+
 spec :: Spec
 spec = do
     describe "ToGraphQL" $ do
@@ -82,7 +101,7 @@ spec = do
              in actual `shouldBe` expected
 
     describe "deriveToGraphQL" $ do
-        it "derives ToGraphQL for a record with multiple fields" $ do
+        it "derives ToGraphQL for a record with multiple fields" $
             let expected = Type.Object $ HashMap.fromList
                     [ ("x", Type.Int 1)
                     , ("y", Type.Boolean True)
@@ -94,8 +113,33 @@ spec = do
                     }
              in toGraphQL given `shouldBe` expected
 
+        it "derives ToGraphQL for a union" $
+            let expected = Type.Object $ HashMap.fromList
+                    [ ("x", Type.Int 2)
+                    , ("y", Type.Boolean False)
+                    , ("__typename", Type.String "TwoFieldRecord")
+                    ]
+                given = SecondVariantUnion $ TwoFieldRecord
+                    { x = 2
+                    , y = False
+                    }
+             in toGraphQL given `shouldBe` expected
+
+        it "derives ToGraphQL for a newtype record" $
+            let expected = Type.Object $ HashMap.fromList
+                    [ ("newTypeField", Type.Int 3)
+                    , ("__typename", Type.String "NewTypeRecord")
+                    ]
+                given = NewTypeRecord 3
+             in toGraphQL given `shouldBe` expected
+
+        it "derives ToGraphQL for an enumeration" $
+            let expected = Type.Enum "TWO_FIELD_ENUM_2"
+                given = TWO_FIELD_ENUM_2
+             in toGraphQL given `shouldBe` expected
+
     describe "deriveFromGraphQL" $ do
-        it "derives FromGraphQL for a record with multiple fields" $ do
+        it "derives FromGraphQL for a record with multiple fields" $
             let given = Type.Object $ HashMap.fromList
                     [ ("x", Type.Int 1)
                     , ("y", Type.Boolean True)
@@ -105,3 +149,13 @@ spec = do
                     , y = True
                     }
              in fromGraphQL given `shouldBe` Just expected
+
+        it "derives FromGraphQL for a newtype record" $
+            let given = Type.Object $ HashMap.singleton "newTypeField" (Type.Int 3)
+                expected = NewTypeRecord 3
+             in fromGraphQL given `shouldBe` Just expected
+
+        it "derives FromGraphQL for an enumeration" $
+            let given = Type.Enum "TWO_FIELD_ENUM_2"
+                expected = TWO_FIELD_ENUM_2
+             in fromGraphQL given `shouldBe` Just expected