Fix "variable is not used" error

…in executor error messages.

.gitea/workflows/build.yml

@@ -0,0 +1,68 @@
+name: Build
+
+on:
+  push:
+  pull_request:
+    branches: [master]
+
+jobs:
+  audit:
+    runs-on: alpine
+    steps:
+      - name: Set up environment
+        shell: ash {0}
+        run: |
+          apk add --no-cache git bash curl build-base readline-dev openssl-dev zlib-dev libpq-dev gmp-dev
+      - name: Prepare system
+        run: |
+          curl --create-dirs --output-dir \
+            ~/.ghcup/bin https://downloads.haskell.org/~ghcup/0.1.19.5/x86_64-linux-ghcup-0.1.19.5 -o ghcup
+          chmod +x ~/.ghcup/bin/ghcup
+          ~/.ghcup/bin/ghcup install ghc 9.4.8
+          ~/.ghcup/bin/ghcup install cabal 3.6.2.0
+      - uses: actions/checkout@v4
+      - name: Install dependencies
+        run: |
+          ~/.ghcup/bin/ghcup run --ghc 9.4.8 --cabal 3.6.2.0 -- cabal update
+          ~/.ghcup/bin/ghcup run --ghc 9.4.8 --cabal 3.6.2.0 -- cabal install hlint --constraint="hlint ==3.6.1"
+      - run: ~/.cabal/bin/hlint -- src tests
+
+  test:
+    runs-on: alpine
+    steps:
+      - name: Set up environment
+        shell: ash {0}
+        run: |
+          apk add --no-cache git bash curl build-base readline-dev openssl-dev zlib-dev libpq-dev gmp-dev
+      - name: Prepare system
+        run: |
+          curl --create-dirs --output-dir \
+            ~/.ghcup/bin https://downloads.haskell.org/~ghcup/0.1.19.5/x86_64-linux-ghcup-0.1.19.5 -o ghcup
+          chmod +x ~/.ghcup/bin/ghcup
+          ~/.ghcup/bin/ghcup install ghc 9.4.8
+          ~/.ghcup/bin/ghcup install cabal 3.6.2.0
+      - uses: actions/checkout@v4
+      - name: Install dependencies
+        run: |
+          ~/.ghcup/bin/ghcup run --ghc 9.4.8 --cabal 3.6.2.0 -- cabal update
+          ~/.ghcup/bin/ghcup run --ghc 9.4.8 --cabal 3.6.2.0 -- cabal build graphql-test
+      - run: ~/.ghcup/bin/ghcup run --ghc 9.4.8 --cabal 3.6.2.0 -- cabal test --test-show-details=direct
+
+  doc:
+    runs-on: alpine
+    steps:
+      - name: Set up environment
+        shell: ash {0}
+        run: |
+          apk add --no-cache git bash curl build-base readline-dev openssl-dev zlib-dev libpq-dev gmp-dev
+      - name: Prepare system
+        run: |
+          curl --create-dirs --output-dir \
+            ~/.ghcup/bin https://downloads.haskell.org/~ghcup/0.1.19.5/x86_64-linux-ghcup-0.1.19.5 -o ghcup
+          chmod +x ~/.ghcup/bin/ghcup
+          ~/.ghcup/bin/ghcup install ghc 9.4.8
+          ~/.ghcup/bin/ghcup install cabal 3.6.2.0
+      - uses: actions/checkout@v4
+      - name: Install dependencies
+        run: ~/.ghcup/bin/ghcup run --ghc 9.4.8 --cabal 3.6.2.0 -- cabal update
+      - run: ~/.ghcup/bin/ghcup run --ghc 9.4.8 --cabal 3.6.2.0 -- cabal haddock --enable-documentation

CHANGELOG.md

@@ -9,6 +9,8 @@ and this project adheres to
 ## [Unreleased]
 ### Fixed
 - `gql` removes not only leading `\n` but also `\r`.
+- Fix non nullable type string representation in executor error messages.
+- Fix input objects not being coerced to lists.
 
 ## [1.2.0.1] - 2023-04-25
 ### Fixed

graphql.cabal

@@ -21,8 +21,8 @@ extra-source-files:
   CHANGELOG.md
   README.md
 tested-with:
-  GHC == 9.2.8,
-  GHC == 9.6.2
+  GHC == 9.4.7,
+  GHC == 9.6.3
 
 source-repository head
   type: git
@@ -106,4 +106,6 @@ test-suite graphql-test
     unordered-containers,
     containers,
     vector
+  build-tool-depends:
+    hspec-discover:hspec-discover
   default-language: Haskell2010

src/Language/GraphQL/AST/Document.hs

@@ -371,8 +371,8 @@ data NonNullType
     deriving Eq
 
 instance Show NonNullType where
-    show (NonNullTypeNamed typeName) = '!' : Text.unpack typeName
-    show (NonNullTypeList listType) =  concat ["![", show listType, "]"]
+    show (NonNullTypeNamed typeName) = Text.unpack $ typeName <> "!"
+    show (NonNullTypeList listType) = concat ["[", show listType, "]!"]
 
 -- ** Directives
 

src/Language/GraphQL/Execute.hs

@@ -556,33 +556,24 @@ coerceArgumentValues argumentDefinitions argumentValues =
                     $ Just inputValue
                 | otherwise -> throwM
                     $ InputCoercionException (Text.unpack argumentName) variableType Nothing
+
     matchFieldValues' = matchFieldValues coerceArgumentValue
         $ Full.node <$> argumentValues
-    coerceArgumentValue inputType (Transform.Int integer) =
-        coerceInputLiteral inputType (Type.Int integer)
-    coerceArgumentValue inputType (Transform.Boolean boolean) =
-        coerceInputLiteral inputType (Type.Boolean boolean)
-    coerceArgumentValue inputType (Transform.String string) =
-        coerceInputLiteral inputType (Type.String string)
-    coerceArgumentValue inputType (Transform.Float float) =
-        coerceInputLiteral inputType (Type.Float float)
-    coerceArgumentValue inputType (Transform.Enum enum) =
-        coerceInputLiteral inputType (Type.Enum enum)
-    coerceArgumentValue inputType Transform.Null
-        | In.isNonNullType inputType = Nothing
-        | otherwise = coerceInputLiteral inputType Type.Null
-    coerceArgumentValue (In.ListBaseType inputType) (Transform.List list) =
-        let coerceItem = coerceArgumentValue inputType
-         in Type.List <$> traverse coerceItem list
-    coerceArgumentValue (In.InputObjectBaseType inputType) (Transform.Object object)
-        | In.InputObjectType _ _ inputFields <- inputType = 
-            let go = forEachField object
-                resultMap = HashMap.foldrWithKey go (pure mempty) inputFields
-             in Type.Object <$> resultMap
-    coerceArgumentValue _ (Transform.Variable variable) = pure variable
-    coerceArgumentValue _ _ = Nothing
-    forEachField object variableName (In.InputField _ variableType defaultValue) =
-        matchFieldValues coerceArgumentValue object variableName variableType defaultValue
+
+    coerceArgumentValue inputType transform =
+      coerceInputLiteral inputType $ extractArgumentValue transform 
+
+    extractArgumentValue (Transform.Int integer) = Type.Int integer
+    extractArgumentValue (Transform.Boolean boolean) = Type.Boolean boolean
+    extractArgumentValue (Transform.String string) = Type.String string
+    extractArgumentValue (Transform.Float float) = Type.Float float
+    extractArgumentValue (Transform.Enum enum) = Type.Enum enum
+    extractArgumentValue Transform.Null = Type.Null
+    extractArgumentValue (Transform.List list) = 
+      Type.List $ extractArgumentValue <$> list
+    extractArgumentValue (Transform.Object object) =
+      Type.Object $ extractArgumentValue <$> object
+    extractArgumentValue (Transform.Variable variable) = variable
 
 collectFields :: Monad m
     => Out.ObjectType m

src/Language/GraphQL/Type/Definition.hs

@@ -18,6 +18,8 @@ module Language.GraphQL.Type.Definition
     , float
     , id
     , int
+    , showNonNullType
+    , showNonNullListType
     , selection
     , string
     ) where
@@ -207,3 +209,11 @@ include = handle include'
             (Just (Boolean True)) -> Include directive'
             _ -> Skip
     include' directive' = Continue directive'
+
+showNonNullType :: Show a => a -> String
+showNonNullType = (++ "!") . show
+
+showNonNullListType :: Show a => a -> String
+showNonNullListType listType =
+    let representation = show listType
+     in concat ["[", representation, "]!"]

src/Language/GraphQL/Type/In.hs

@@ -66,10 +66,11 @@ instance Show Type where
     show (NamedEnumType enumType) = show enumType
     show (NamedInputObjectType inputObjectType) = show inputObjectType
     show (ListType baseType) = concat ["[", show baseType, "]"]
-    show (NonNullScalarType scalarType) = '!' : show scalarType
-    show (NonNullEnumType enumType) = '!' : show enumType
-    show (NonNullInputObjectType inputObjectType) = '!' : show inputObjectType
-    show (NonNullListType baseType) = concat ["![", show baseType, "]"]
+    show (NonNullScalarType scalarType) = Definition.showNonNullType scalarType
+    show (NonNullEnumType enumType) = Definition.showNonNullType enumType
+    show (NonNullInputObjectType inputObjectType) =
+        Definition.showNonNullType inputObjectType
+    show (NonNullListType baseType) = Definition.showNonNullListType baseType
 
 -- | Field argument definition.
 data Argument = Argument (Maybe Text) Type (Maybe Definition.Value)

src/Language/GraphQL/Type/Out.hs

@@ -115,12 +115,12 @@ instance forall a. Show (Type a) where
     show (NamedInterfaceType interfaceType) = show interfaceType
     show (NamedUnionType unionType) = show unionType
     show (ListType baseType) = concat ["[", show baseType, "]"]
-    show (NonNullScalarType scalarType) = '!' : show scalarType
-    show (NonNullEnumType enumType) = '!' : show enumType
-    show (NonNullObjectType inputObjectType) = '!' : show inputObjectType
-    show (NonNullInterfaceType interfaceType) = '!' : show interfaceType
-    show (NonNullUnionType unionType) = '!' : show unionType
-    show (NonNullListType baseType) = concat ["![", show baseType, "]"]
+    show (NonNullScalarType scalarType) = showNonNullType scalarType
+    show (NonNullEnumType enumType) = showNonNullType enumType
+    show (NonNullObjectType inputObjectType) = showNonNullType inputObjectType
+    show (NonNullInterfaceType interfaceType) = showNonNullType interfaceType
+    show (NonNullUnionType unionType) = showNonNullType unionType
+    show (NonNullListType baseType) = showNonNullListType baseType
 
 -- | Matches either 'NamedScalarType' or 'NonNullScalarType'.
 pattern ScalarBaseType :: forall m. ScalarType -> Type m

src/Language/GraphQL/Validate/Rules.hs

@@ -618,6 +618,10 @@ noUndefinedVariablesRule =
         , "\"."
         ]
 
+-- Used to find the difference between defined and used variables. The first
+-- argument are variables defined in the operation, the second argument are
+-- variables used in the query. It should return the difference between these
+-- 2 sets.
 type UsageDifference
     = HashMap Full.Name [Full.Location]
     -> HashMap Full.Name [Full.Location]
@@ -664,11 +668,26 @@ variableUsageDifference difference errorMessage = OperationDefinitionRule $ \cas
         = filterSelections' selections
         >>= lift . mapReaderT (<> mapDirectives directives') . pure
     findDirectiveVariables (Full.Directive _ arguments _) = mapArguments arguments
-    mapArguments = Seq.fromList . mapMaybe findArgumentVariables
+
+    mapArguments = Seq.fromList . (>>= findArgumentVariables)
     mapDirectives = foldMap findDirectiveVariables
-    findArgumentVariables (Full.Argument _ Full.Node{ node = Full.Variable value', ..} _) =
-        Just (value', [location])
-    findArgumentVariables _ = Nothing
+
+    findArgumentVariables (Full.Argument _ Full.Node{node = value, ..} _) =
+        findValueVariables location value
+
+    findValueVariables location (Full.Variable value') = [(value', [location])]
+    findValueVariables location (Full.List values) =
+        values
+            >>= (\(Full.Node{node = value}) -> findValueVariables location value)
+    findValueVariables _ (Full.Object fields) =
+        fields
+            >>= ( \( Full.ObjectField
+                        { location = location
+                        , value = Full.Node{node = value}
+                        }
+                    ) -> findValueVariables location value
+                )
+    findValueVariables _ _ = []
     makeError operationName (variableName, locations') = Error
         { message = errorMessage operationName variableName
         , locations = locations'

tests/Language/GraphQL/ExecuteSpec.hs

@@ -69,6 +69,7 @@ queryType = Out.ObjectType "Query" Nothing []
     , ("throwing", ValueResolver throwingField throwingResolver)
     , ("count", ValueResolver countField countResolver)
     , ("sequence", ValueResolver sequenceField sequenceResolver)
+    , ("withInputObject", ValueResolver withInputObjectField withInputObjectResolver)
     ]
   where
     philosopherField =
@@ -89,6 +90,17 @@ queryType = Out.ObjectType "Query" Nothing []
         let fieldType = Out.ListType $ Out.NonNullScalarType int
          in Out.Field Nothing fieldType HashMap.empty
     sequenceResolver = pure intSequence
+    withInputObjectResolver = pure $ Type.Int 0
+    withInputObjectField =
+        Out.Field Nothing (Out.NonNullScalarType int) $ HashMap.fromList
+            [("values", In.Argument Nothing withInputObjectArgumentType Nothing)]
+    withInputObjectArgumentType = In.NonNullListType
+        $ In.NonNullInputObjectType inputObjectType
+
+inputObjectType :: In.InputObjectType
+inputObjectType = In.InputObjectType "InputObject" Nothing $
+    HashMap.singleton "name" $
+        In.InputField Nothing (In.NonNullScalarType int) Nothing
 
 intSequence :: Value
 intSequence = Type.List [Type.Int 1, Type.Int 2, Type.Int 3]
@@ -295,7 +307,7 @@ spec =
                 let data'' = Object $ HashMap.singleton "philosopher" Null
                     executionErrors = pure $ Error
                         { message =
-                            "Value completion error. Expected type !School, found: EXISTENTIALISM."
+                            "Value completion error. Expected type School!, found: EXISTENTIALISM."
                         , locations = [Location 1 17]
                         , path = [Segment "philosopher", Segment "school"]
                         }
@@ -307,7 +319,7 @@ spec =
                 let data'' = Object $ HashMap.singleton "philosopher" Null
                     executionErrors = pure $ Error
                         { message =
-                            "Value completion error. Expected type !Interest, found: { instrument: \"piano\" }."
+                            "Value completion error. Expected type Interest!, found: { instrument: \"piano\" }."
                         , locations = [Location 1 17]
                         , path = [Segment "philosopher", Segment "interest"]
                         }
@@ -319,7 +331,7 @@ spec =
                 let data'' = Object $ HashMap.singleton "philosopher" Null
                     executionErrors = pure $ Error
                         { message
-                            = "Value completion error. Expected type !Work, found:\
+                            = "Value completion error. Expected type Work!, found:\
                             \ { title: \"Also sprach Zarathustra: Ein Buch f\252r Alle und Keinen\" }."
                         , locations = [Location 1 17]
                         , path = [Segment "philosopher", Segment "majorWork"]
@@ -328,22 +340,10 @@ spec =
                     sourceQuery = "{ philosopher { majorWork { title } } }"
                  in sourceQuery `shouldResolveTo` expected
 
-            it "gives location information for invalid scalar arguments" $
-                let data'' = Object $ HashMap.singleton "philosopher" Null
-                    executionErrors = pure $ Error
-                        { message =
-                            "Argument \"id\" has invalid type. Expected type ID, found: True."
-                        , locations = [Location 1 15]
-                        , path = [Segment "philosopher"]
-                        }
-                    expected = Response data'' executionErrors
-                    sourceQuery = "{ philosopher(id: true) { lastName } }"
-                 in sourceQuery `shouldResolveTo` expected
-
             it "gives location information for failed result coercion" $
                 let data'' = Object $ HashMap.singleton "philosopher" Null
                     executionErrors = pure $ Error
-                        { message = "Unable to coerce result to !Int."
+                        { message = "Unable to coerce result to Int!."
                         , locations = [Location 1 26]
                         , path = [Segment "philosopher", Segment "century"]
                         }
@@ -364,7 +364,7 @@ spec =
 
             it "sets data to null if a root field isn't nullable" $
                 let executionErrors = pure $ Error
-                        { message = "Unable to coerce result to !Int."
+                        { message = "Unable to coerce result to Int!."
                         , locations = [Location 1 3]
                         , path = [Segment "count"]
                         }
@@ -375,7 +375,7 @@ spec =
             it "detects nullability errors" $
                 let data'' = Object $ HashMap.singleton "philosopher" Null
                     executionErrors = pure $ Error
-                        { message = "Value completion error. Expected type !String, found: null."
+                        { message = "Value completion error. Expected type String!, found: null."
                         , locations = [Location 1 26]
                         , path = [Segment "philosopher", Segment "firstLanguage"]
                         }
@@ -389,6 +389,25 @@ spec =
                     sourceQuery = "{ sequence }"
                 in sourceQuery `shouldResolveTo` expected
 
+            context "Arguments" $ do
+                it "gives location information for invalid scalar arguments" $
+                    let data'' = Object $ HashMap.singleton "philosopher" Null
+                        executionErrors = pure $ Error
+                            { message =
+                                "Argument \"id\" has invalid type. Expected type ID, found: True."
+                            , locations = [Location 1 15]
+                            , path = [Segment "philosopher"]
+                            }
+                        expected = Response data'' executionErrors
+                        sourceQuery = "{ philosopher(id: true) { lastName } }"
+                    in sourceQuery `shouldResolveTo` expected
+
+                it "puts an object in a list if needed" $
+                    let data'' = Object $ HashMap.singleton "withInputObject" $ Type.Int 0
+                        expected = Response data'' mempty
+                        sourceQuery = "{ withInputObject(values: { name: 0 }) }"
+                    in sourceQuery `shouldResolveTo` expected
+
             context "queryError" $ do
                 let namedQuery name = "query " <> name <> " { philosopher(id: \"1\") { interest } }"
                     twoQueries = namedQuery "A" <> " " <> namedQuery "B"

tests/Language/GraphQL/Validate/RulesSpec.hs

@@ -18,7 +18,7 @@ import Language.GraphQL.Type
 import qualified Language.GraphQL.Type.In as In
 import qualified Language.GraphQL.Type.Out as Out
 import Language.GraphQL.Validate
-import Test.Hspec (Spec, context, describe, it, shouldBe, shouldContain)
+import Test.Hspec (Spec, context, describe, it, shouldBe, shouldContain, xit)
 import Text.Megaparsec (parse, errorBundlePretty)
 
 petSchema :: Schema IO
@@ -560,7 +560,7 @@ spec =
                         }
                  in validate queryString `shouldBe` [expected]
 
-        context "noUnusedVariablesRule" $
+        context "noUnusedVariablesRule" $ do
             it "rejects unused variables" $
                 let queryString = [gql|
                   query variableUnused($atOtherHomes: Boolean) {
@@ -577,6 +577,16 @@ spec =
                         }
                  in validate queryString `shouldBe` [expected]
 
+            xit "detects variables in properties of input objects" $
+                let queryString = [gql|
+                  query withVar ($name: String!) {
+                    findDog (complex: { name: $name }) {
+                      name
+                    }
+                  }
+                |]
+                 in validate queryString `shouldBe` []
+
         context "uniqueInputFieldNamesRule" $
             it "rejects duplicate fields in input objects" $
                 let queryString = [gql|
@@ -878,7 +888,7 @@ spec =
                         { message =
                             "Variable \"$dogCommandArg\" of type \
                             \\"DogCommand\" used in position expecting type \
-                            \\"!DogCommand\"."
+                            \\"DogCommand!\"."
                         , locations = [AST.Location 1 26]
                         }
                  in validate queryString `shouldBe` [expected]
@@ -925,7 +935,7 @@ spec =
                 |]
                     expected = Error
                         { message =
-                            "Value 3 cannot be coerced to type \"!CatCommand\"."
+                            "Value 3 cannot be coerced to type \"CatCommand!\"."
                         , locations = [AST.Location 3 36]
                         }
                  in validate queryString `shouldBe` [expected]
@@ -940,7 +950,7 @@ spec =
                 |]
                     expected = Error
                         { message =
-                            "Value 3 cannot be coerced to type \"!String\"."
+                            "Value 3 cannot be coerced to type \"String!\"."
                         , locations = [AST.Location 2 28]
                         }
                  in validate queryString `shouldBe` [expected]