Fix for ArgBuilder with when input is a value type

core/src/main/scala-2/caliban/schema/ArgBuilderDerivation.scala

@@ -46,7 +46,7 @@ trait CommonArgBuilderDerivation {
     def build(input: InputValue): Either[ExecutionError, T] =
       input match {
         case InputValue.ObjectValue(fields) => fromFields(fields)
-        case _                              => Left(ExecutionError("expected an input object"))
+        case value                          => ctx.constructMonadic(p => p.typeclass.build(value))
       }
 
     private[this] def fromFields(fields: Map[String, InputValue]): Either[ExecutionError, T] =

core/src/main/scala-3/caliban/schema/ArgBuilderDerivation.scala

@@ -1,6 +1,7 @@
 package caliban.schema
 
 import caliban.CalibanError.ExecutionError
+import caliban.InputValue.{ ListValue, VariableValue }
 import caliban.Value.*
 import caliban.schema.Annotations.{ GQLDefault, GQLName, GQLOneOfInput }
 import caliban.schema.macros.Macros
@@ -140,24 +141,39 @@ trait CommonArgBuilderDerivation {
     def build(input: InputValue): Either[ExecutionError, A] =
       input match {
         case InputValue.ObjectValue(fields) => fromFields(fields)
-        case _                              => Left(ExecutionError("expected an input object"))
+        case value                          => fromValue(value)
       }
 
     private def fromFields(fields: Map[String, InputValue]): Either[ExecutionError, A] = {
-      var i          = 0
-      val l          = params.length
-      var acc: Tuple = EmptyTuple
+      var i   = 0
+      val l   = params.length
+      val arr = Array.ofDim[Any](l)
       while (i < l) {
         val (label, default, builder) = params(i)
         val field                     = fields.getOrElse(label, null)
         val value                     = if (field ne null) builder.build(field) else default
         value match {
-          case Right(v)    => acc :*= v
-          case e @ Left(_) => return e.asInstanceOf[Either[ExecutionError, A]]
+          case Right(v) => arr(i) = v
+          case Left(e)  => return Left(e)
         }
         i += 1
       }
-      Right(fromProduct(acc))
+      Right(fromProduct(Tuple.fromArray(arr)))
+    }
+
+    private def fromValue(input: InputValue): Either[ExecutionError, A] = {
+      val l   = params.length
+      val arr = Array.ofDim[Any](l)
+      var i   = 0
+      while (i < l) {
+        val (_, _, builder) = params(i)
+        builder.build(input) match {
+          case Right(v) => arr(i) = v
+          case Left(e)  => return Left(e)
+        }
+        i += 1
+      }
+      Right(fromProduct(Tuple.fromArray(arr)))
     }
 
   }

core/src/test/scala-2/caliban/schema/ArgBuilderScala2Spec.scala

@@ -0,0 +1,27 @@
+package caliban.schema
+
+import caliban.Value.StringValue
+import caliban.schema.ArgBuilder.auto._
+import zio.test.Assertion._
+import zio.test._
+
+import java.util.UUID
+
+object ArgBuilderScala2Spec extends ZIOSpecDefault {
+  def spec = suite("ArgBuilderScala2")(
+    suite("AnyVal") {
+      test("ArgBuilder that extends AnyVal") {
+        val id    = UUID.randomUUID()
+        val value = ArgBuilder[UUIDId].build(StringValue(id.toString))
+        assert(value)(isRight(equalTo(UUIDId(id))))
+      }
+    }
+  )
+
+  trait Ids[T] extends Any {
+    self: AnyVal =>
+    def value: T
+  }
+
+  final case class UUIDId(value: UUID) extends AnyVal with Ids[UUID]
+}

core/src/test/scala/caliban/execution/ExecutionSpec.scala

@@ -860,6 +860,27 @@ object ExecutionSpec extends ZIOSpecDefault {
           .flatMap(_.execute(query))
           .map(result => assertTrue(result.data.toString == """null"""))
       },
+      test("using value types as inputs") {
+        @GQLValueType
+        case class UserArgs(id: Int)
+        case class User(test: UserArgs => String)
+        case class Mutations(user: UIO[User])
+        case class Queries(a: Int)
+        val api = graphQL(RootResolver(Queries(1), Mutations(ZIO.succeed(User(_.toString)))))
+
+        val interpreter = api.interpreter
+        val query       =
+          """mutation {
+            |  user {
+            |    test(value: 123)
+            |  }
+            |}""".stripMargin
+        interpreter
+          .flatMap(_.execute(query))
+          .debug
+          .map(_.data.toString)
+          .map(result => assertTrue(result == """{"user":{"test":"UserArgs(123)"}}"""))
+      },
       test("die inside a nullable list") {
         case class Queries(test: List[Task[String]])
         val api         = graphQL(RootResolver(Queries(List(ZIO.succeed("a"), ZIO.die(new Exception("Boom"))))))