@Test
    fun test() {
        val schemaString = """
            type Query {
                cat: Cat!
            }
            
            type Cat {
                foo1: String!
                foo2: String!
            }
        """.trimIndent()

        val documentString = """
            query GetCat {
              cat {
                foo1
                foo1: foo2
              }
            }

        """.trimIndent()
        val typeDefinitionRegistry = SchemaParser().parse(schemaString)
        val document = Parser().parseDocument(documentString)
        val graphQLSchema = SchemaGenerator().makeExecutableSchema(typeDefinitionRegistry, RuntimeWiring.newRuntimeWiring().build())
        val result = Validator().validateDocument(graphQLSchema, document, Locale.US)

        // There should be a validation error at this point.
        check(result.isNotEmpty())
    }