fix some scalac warnings

modules/core/src/main/scala/sangria/execution/FutureResolver.scala

@@ -226,7 +226,7 @@ private[execution] class FutureResolver[Ctx](
   private def marshallExtensions: Option[marshaller.Node] = {
     val extensions =
       middleware.flatMap {
-        case (v, m: MiddlewareExtension[Ctx]) =>
+        case (v, m: MiddlewareExtension[Ctx @unchecked]) =>
           m.afterQueryExtensions(v.asInstanceOf[m.QueryVal], middlewareCtx)
         case _ => Nil
       }

modules/core/src/main/scala/sangria/execution/InputDocumentMaterializer.scala

@@ -85,13 +85,13 @@ case class InputDocumentMaterializer[Vars](
             typeInfo.withInputType(inputType)
 
             AstVisitor {
-              case v: ast.VariableValue if typeInfo.inputType.isDefined =>
+              case v2: ast.VariableValue if typeInfo.inputType.isDefined =>
                 val parentType = typeInfo.inputType.get
                 val parentTypeAst = SchemaRenderer.renderTypeNameAst(parentType)
 
-                state.get(v.name) match {
+                state.get(v2.name) match {
                   case None =>
-                    state(v.name) = ast.VariableDefinition(v.name, parentTypeAst, None)
+                    state(v2.name) = ast.VariableDefinition(v2.name, parentTypeAst, None)
                     VisitorCommand.Continue
                   case _ => VisitorCommand.Continue
                 }

modules/core/src/main/scala/sangria/execution/QueryReducerExecutor.scala

@@ -163,7 +163,6 @@ object QueryReducerExecutor {
         case ScalarAlias(aliasFor, _, _) =>
           reducers.map(_.reduceScalar(path, userContext, aliasFor))
         case e: EnumType[_] => reducers.map(_.reduceEnum(path, userContext, e))
-        case _ => initialValues
       }
 
     val reduced = fields.fields.foldLeft(Array(initialValues: _*)) {

modules/core/src/main/scala/sangria/renderer/QueryRenderer.scala

@@ -506,13 +506,13 @@ object QueryRenderer {
     node match {
       case d @ Document(defs, _, _, _) =>
         defs.iterator
-          .map(renderNode(_, config, indent))
+          .map(renderNode(_, config, indent, prefix = None, prev = None))
           .mkString(config.definitionSeparator) +
           renderTrailingComment(d, None, indent, config)
 
       case d @ InputDocument(defs, _, _, _) =>
         defs.iterator
-          .map(renderNode(_, config, indent))
+          .map(renderNode(_, config, indent, prefix = None, prev = None))
           .mkString(config.definitionSeparator) +
           renderTrailingComment(d, None, indent, config)
 
@@ -547,16 +547,21 @@ object QueryRenderer {
       case vd @ VariableDefinition(name, tpe, defaultValue, dirs, _, _) =>
         renderComment(vd, prev, indent, config) +
           indent.str + "$" + name + ":" + config.separator +
-          renderNode(tpe, config, indent.zero) +
+          renderNode(tpe, config, indent.zero, prefix = None, prev = None) +
           defaultValue.fold("")(v =>
-            config.separator + "=" + config.separator + renderNode(v, config, indent.zero)) +
+            config.separator + "=" + config.separator + renderNode(
+              v,
+              config,
+              indent.zero,
+              prefix = None,
+              prev = None)) +
           renderDirs(dirs, config, indent, frontSep = true)
 
       case NotNullType(ofType, _) =>
-        renderNode(ofType, config, indent.zero) + "!"
+        renderNode(ofType, config, indent.zero, prefix = None, prev = None) + "!"
 
       case ListType(ofType, _) =>
-        "[" + renderNode(ofType, config, indent.zero) + "]"
+        "[" + renderNode(ofType, config, indent.zero, prefix = None, prev = None) + "]"
 
       case NamedType(name, _) =>
         name
@@ -589,7 +594,12 @@ object QueryRenderer {
 
       case a @ Argument(name, value, _, _) =>
         renderComment(a, prev, indent, config) +
-          indent.str + name + ":" + config.separator + renderNode(value, config, indent.zero)
+          indent.str + name + ":" + config.separator + renderNode(
+            value,
+            config,
+            indent.zero,
+            prefix = None,
+            prev = None)
 
       case v @ IntValue(value, _, _) => renderInputComment(v, indent, config) + value
       case v @ BigIntValue(value, _, _) => renderInputComment(v, indent, config) + value
@@ -611,9 +621,19 @@ object QueryRenderer {
           if (config.formatInputValues && shouldRenderComment(v, None, config))
             (if (idx != 0) config.lineBreak else "") +
               config.lineBreak +
-              renderNode(v, config, indent + (if (addIdent(v)) 1 else 0))
+              renderNode(
+                v,
+                config,
+                indent + (if (addIdent(v)) 1 else 0),
+                prefix = None,
+                prev = None)
           else
-            (if (idx != 0) config.separator else "") + renderNode(v, config, indent)
+            (if (idx != 0) config.separator else "") + renderNode(
+              v,
+              config,
+              indent,
+              prefix = None,
+              prev = None)
 
         renderInputComment(v, indent, config) +
           "[" + value.iterator.zipWithIndex
@@ -626,17 +646,22 @@ object QueryRenderer {
             .map { case (v, idx) =>
               (if (idx != 0 && config.formatInputValues && shouldRenderComment(v, None, config))
                  config.lineBreak
-               else "") + renderNode(v, config, inputFieldIndent(config, indent))
+               else "") + renderNode(
+                v,
+                config,
+                inputFieldIndent(config, indent),
+                prefix = None,
+                prev = None)
             }
             .mkString(config.inputFieldSeparator) +
           inputLineBreak(config) + inputIndent(config, indent) + "}"
       case VariableValue(name, _, _) => indent.str + "$" + name
       case v @ ObjectField(name, value, _, _) =>
         val rendered =
           if (config.formatInputValues && shouldRenderComment(value, None, config))
-            config.lineBreak + renderNode(value, config, indent.inc)
+            config.lineBreak + renderNode(value, config, indent.inc, prefix = None, prev = None)
           else
-            config.separator + renderNode(value, config, indent)
+            config.separator + renderNode(value, config, indent, prefix = None, prev = None)
 
         (if (config.formatInputValues) renderComment(v, prev, indent, config) else "") +
           indent.str + name + ":" + rendered
@@ -681,7 +706,7 @@ object QueryRenderer {
           if (types.nonEmpty)
             config.separator + "=" + config.separator +
               types.iterator
-                .map(renderNode(_, config, indent.zero))
+                .map(renderNode(_, config, indent.zero, prefix = None, prev = None))
                 .mkString(config.separator + "|" + config.separator)
           else
             ""
@@ -709,15 +734,30 @@ object QueryRenderer {
           renderComment(fd, description.orElse(prev), indent, config) +
           indent.str + name +
           renderInputValueDefs(args, indent, config, withSep = false) +
-          ":" + config.separator + renderNode(fieldType, config, indent.zero) +
+          ":" + config.separator + renderNode(
+            fieldType,
+            config,
+            indent.zero,
+            prefix = None,
+            prev = None) +
           renderDirs(dirs, config, indent, frontSep = true)
 
       case ivd @ InputValueDefinition(name, valueType, default, dirs, description, _, _) =>
         renderDescription(ivd, prev, indent, config) +
           renderComment(ivd, description.orElse(prev), indent, config) +
-          indent.str + name + ":" + config.separator + renderNode(valueType, config, indent.zero) +
+          indent.str + name + ":" + config.separator + renderNode(
+            valueType,
+            config,
+            indent.zero,
+            prefix = None,
+            prev = None) +
           default.fold("")(d =>
-            config.separator + "=" + config.separator + renderNode(d, config, indent.zero)) +
+            config.separator + "=" + config.separator + renderNode(
+              d,
+              config,
+              indent.zero,
+              prefix = None,
+              prev = None)) +
           renderDirs(dirs, config, indent, frontSep = true)
 
       case ted @ ObjectTypeExtensionDefinition(name, interfaces, fields, dirs, _, _, _) =>
@@ -744,7 +784,7 @@ object QueryRenderer {
           if (types.nonEmpty)
             config.separator + "=" + config.separator +
               types.iterator
-                .map(renderNode(_, config, indent.zero))
+                .map(renderNode(_, config, indent.zero, prefix = None, prev = None))
                 .mkString(config.separator + "|" + config.separator)
           else
             ""
@@ -787,7 +827,9 @@ object QueryRenderer {
               renderNode(
                 l,
                 config,
-                if (shouldRenderComment(l, None, config)) indent.inc else indent.zero)
+                if (shouldRenderComment(l, None, config)) indent.inc else indent.zero,
+                prefix = None,
+                prev = None)
           }
 
         renderDescription(dd, prev, indent, config) +
@@ -815,7 +857,9 @@ object QueryRenderer {
           indent.str + renderOpType(op) + ":" + config.separator + renderNode(
             tpe,
             config,
-            indent.zero)
+            indent.zero,
+            prefix = None,
+            prev = None)
     }
 
   private def trailingLineBreak(tc: WithTrailingComments, config: QueryRendererConfig) =

modules/core/src/main/scala/sangria/renderer/SchemaRenderer.scala

@@ -314,7 +314,6 @@ object SchemaRenderer {
       case io: IntrospectionInputObjectType => renderInputObject(io)
       case s: IntrospectionScalarType => renderScalar(s)
       case e: IntrospectionEnumType => renderEnum(e)
-      case kind => throw new IllegalArgumentException(s"Unsupported kind: $kind")
     }
 
   def renderType(tpe: Type with Named): ast.TypeDefinition =

modules/core/src/main/scala/sangria/schema/AstSchemaBuilder.scala

@@ -73,7 +73,7 @@ trait AstSchemaBuilder[Ctx] {
       interfaces: List[InterfaceType[Ctx, Any]],
       mat: AstSchemaMaterializer[Ctx]): Option[InterfaceType[Ctx, Any]]
 
-  @deprecated
+  @deprecated(message = "Use buildInterfaceType with interfaces parameter", since = "4.0")
   def buildInterfaceType(
       origin: MatOrigin,
       definition: ast.InterfaceTypeDefinition,
@@ -89,7 +89,7 @@ trait AstSchemaBuilder[Ctx] {
       interfaces: List[InterfaceType[Ctx, Any]],
       mat: AstSchemaMaterializer[Ctx]): InterfaceType[Ctx, Any]
 
-  @deprecated
+  @deprecated(message = "Use extendInterfaceType with interfaces parameter", since = "4.0")
   def extendInterfaceType(
       origin: MatOrigin,
       existing: InterfaceType[Ctx, _],

modules/core/src/main/scala/sangria/schema/AstSchemaMaterializer.scala

@@ -113,7 +113,9 @@ class AstSchemaMaterializer[Ctx] private (
       unionTypeExtensionDefs.isEmpty)
       schema
     else {
-      existingDefsMat = schema.allTypes.mapValues(MaterializedType(existingOrigin, _)).toMap
+      existingDefsMat = schema.allTypes.iterator.map { case (k, v) =>
+        (k, MaterializedType(existingOrigin, v))
+      }.toMap
 
       val queryType = getTypeFromDef(existingOrigin, schema.query)
 
@@ -647,9 +649,9 @@ class AstSchemaMaterializer[Ctx] private (
         extendScalarAlias(origin, tpe.asInstanceOf[ScalarAlias[Any, Any]])
       case tpe: EnumType[_] => extendEnumType(origin, tpe)
       case tpe: InputObjectType[_] => extendInputObjectType(origin, tpe)
-      case tpe: UnionType[Ctx] => extendUnionType(origin, tpe)
-      case tpe: ObjectType[Ctx, _] => extendObjectType(origin, tpe)
-      case tpe: InterfaceType[Ctx, _] => extendInterfaceType(origin, tpe)
+      case tpe: UnionType[Ctx @unchecked] => extendUnionType(origin, tpe)
+      case tpe: ObjectType[Ctx @unchecked, _] => extendObjectType(origin, tpe)
+      case tpe: InterfaceType[Ctx @unchecked, _] => extendInterfaceType(origin, tpe)
     }
 
   def buildField(

modules/core/src/main/scala/sangria/schema/ResolverBasedAstSchemaBuilder.scala

@@ -609,9 +609,6 @@ object ResolverBasedAstSchemaBuilder {
 
       if (iu.isMapNode(objValue)) objValue
       else invalidType("Object", objValue)
-    case t =>
-      throw SchemaMaterializationException(
-        s"Extractor for a type '${SchemaRenderer.renderTypeName(t)}' is not supported yet.")
   }
 
   def extractFieldValue[Ctx, In](context: Context[Ctx, _])(implicit

modules/core/src/main/scala/sangria/schema/Schema.scala

@@ -29,7 +29,6 @@ sealed trait Type {
         case ListInputType(ofType) => getNamedType(ofType)
         case ListType(ofType) => getNamedType(ofType)
         case n: Named => n
-        case t => throw new IllegalStateException("Expected named type, but got: " + t)
       }
 
     getNamedType(this)
@@ -360,7 +359,7 @@ object ObjectType {
       description: Option[String],
       interfaces: List[InterfaceType[Ctx, _]],
       fieldsFn: () => List[Field[Ctx, Val]]) =
-    ObjectType(
+    new ObjectType(
       name,
       description,
       fieldsFn,
@@ -498,28 +497,29 @@ case class PossibleInterface[Ctx, Concrete](interfaceType: InterfaceType[Ctx, _]
 object PossibleInterface extends PossibleInterfaceLowPrioImplicits {
   def apply[Ctx, Abstract, Concrete](interface: InterfaceType[Ctx, Abstract])(implicit
       ev: PossibleType[Abstract, Concrete]): PossibleInterface[Ctx, Concrete] =
-    PossibleInterface[Ctx, Concrete](interface)
+    new PossibleInterface[Ctx, Concrete](interface)
+
   implicit def convert[Ctx, Abstract, Concrete](interface: InterfaceType[Ctx, Abstract])(implicit
       ev: PossibleType[Abstract, Concrete]): PossibleInterface[Ctx, Concrete] =
-    PossibleInterface[Ctx, Concrete](interface)
+    new PossibleInterface[Ctx, Concrete](interface)
 }
 
 trait PossibleInterfaceLowPrioImplicits {
   implicit def applyUnit[Ctx, Abstract, Concrete](interface: InterfaceType[Ctx, Abstract])(implicit
       ev: PossibleType[Abstract, Concrete]): PossibleInterface[Unit, Concrete] =
-    PossibleInterface[Unit, Concrete](interface.asInstanceOf[InterfaceType[Unit, Abstract]])
+    new PossibleInterface[Unit, Concrete](interface.asInstanceOf[InterfaceType[Unit, Abstract]])
 }
 
 case class PossibleObject[Ctx, Abstract](objectType: ObjectType[Ctx, _])
 
 object PossibleObject {
   implicit def apply[Ctx, Abstract, Concrete](obj: ObjectType[Ctx, Concrete])(implicit
       ev: PossibleType[Abstract, Concrete]): PossibleObject[Ctx, Abstract] =
-    PossibleObject[Ctx, Abstract](obj)
+    new PossibleObject[Ctx, Abstract](obj)
 
   implicit def applyUnit[Ctx, Abstract, Concrete](obj: ObjectType[Unit, Concrete])(implicit
       ev: PossibleType[Abstract, Concrete]): PossibleObject[Ctx, Abstract] =
-    PossibleObject[Ctx, Abstract](obj.asInstanceOf[ObjectType[Ctx, Concrete]])
+    new PossibleObject[Ctx, Abstract](obj.asInstanceOf[ObjectType[Ctx, Concrete]])
 }
 
 trait PossibleType[AbstrType, ConcreteType]
@@ -1547,8 +1547,9 @@ case class Schema[Ctx, Val](
   def getOutputType(tpe: ast.Type, topLevel: Boolean = false): Option[OutputType[_]] = tpe match {
     case ast.NamedType(name, _) =>
       outputTypes.get(name).map(ot => if (topLevel) ot else OptionType(ot))
-    case ast.NotNullType(ofType, _) => getOutputType(ofType).collect { case OptionType(ot) => ot }
-    case ast.ListType(ofType, _) => getOutputType(ofType).map(ListType(_))
+    case ast.NotNullType(ofType, _) =>
+      getOutputType(ofType, topLevel = false).collect { case OptionType(ot) => ot }
+    case ast.ListType(ofType, _) => getOutputType(ofType, topLevel = false).map(ListType(_))
   }
 
   lazy val directImplementations: Map[String, Vector[ObjectLikeType[_, _]]] =

modules/core/src/main/scala/sangria/schema/SchemaComparator.scala

@@ -138,7 +138,7 @@ object SchemaComparator {
     )
 
     val descriptionChanges =
-      findDescriptionChanged(oldSchema, newSchema, SchemaChange.SchemaDescriptionChanged)
+      findDescriptionChanged(oldSchema, newSchema, SchemaChange.SchemaDescriptionChanged.apply)
 
     withSubscription ++ directiveChanges ++ descriptionChanges
   }

modules/core/src/test/scala/sangria/util/CatsSupport.scala

@@ -240,8 +240,6 @@ object CatsScenarioExecutor extends FutureResultSupport {
                 operationName = op,
                 exceptionHandler = exceptionHandler)
               .await))
-    case a =>
-      throw new IllegalStateException(s"Not yet supported action: $a")
   }
 
   val exceptionHandler = ExceptionHandler { case (_, e: ResolveException) =>