fix some compile warnings (ExpediaGroup#285)

No impact on any library code

Author: smyrick

graphql-kotlin-spring-example/src/main/kotlin/com/expedia/graphql/sample/datafetchers/SpringDataFetcherFactory.kt

@@ -16,6 +16,7 @@ class SpringDataFetcherFactory: DataFetcherFactory<Any>, BeanFactoryAware {
         this.beanFactory = beanFactory!!
     }
 
+    @Suppress("UNCHECKED_CAST")
     override fun get(environment: DataFetcherFactoryEnvironment?): DataFetcher<Any> {
 
         //Strip out possible `Input` and `!` suffixes added to by the SchemaGenerator

graphql-kotlin-spring-example/src/main/kotlin/com/expedia/graphql/sample/extension/CustomSchemaGeneratorHooks.kt

@@ -28,10 +28,11 @@ class CustomSchemaGeneratorHooks(validator: Validator, override val wiringFactor
     override val dataFetcherExecutionPredicate: DataFetcherExecutionPredicate? = DataFetcherExecutionValidator(validator)
 }
 
-internal val graphqlUUIDType = GraphQLScalarType("UUID",
-        "A type representing a formatted java.util.UUID",
-        UUIDCoercing
-)
+internal val graphqlUUIDType = GraphQLScalarType.newScalar()
+    .name("UUID")
+    .description("A type representing a formatted java.util.UUID")
+    .coercing(UUIDCoercing)
+    .build()
 
 private object UUIDCoercing : Coercing<UUID, String> {
     override fun parseValue(input: Any?): UUID = UUID.fromString(

graphql-kotlin-spring-example/src/main/kotlin/com/expedia/graphql/sample/query/PolymorphicQuery.kt

@@ -20,7 +20,6 @@ class PolymorphicQuery: Query {
     fun animal(type: AnimalType): Animal? = when (type) {
         AnimalType.CAT -> Cat()
         AnimalType.DOG -> Dog()
-        else -> null
     }
 
     fun dog(): Dog = Dog()

graphql-kotlin-spring-example/src/test/kotlin/com/expedia/graphql/sample/extension/CustomSchemaGeneratorHooksTest.kt

@@ -0,0 +1,37 @@
+package com.expedia.graphql.sample.extension
+
+import com.expedia.graphql.directives.KotlinDirectiveWiringFactory
+import io.mockk.mockk
+import org.junit.jupiter.api.Test
+import java.util.UUID
+import javax.validation.Validator
+import kotlin.reflect.full.createType
+import kotlin.test.assertEquals
+import kotlin.test.assertNotNull
+import kotlin.test.assertNull
+
+class CustomSchemaGeneratorHooksTest {
+
+    data class NonScalar(val id: String)
+
+    @Test
+    fun `UUID returns a string scalar`() {
+        val validator: Validator = mockk()
+        val wiringFactory: KotlinDirectiveWiringFactory = mockk()
+        val hooks = CustomSchemaGeneratorHooks(validator, wiringFactory)
+
+        val result = hooks.willGenerateGraphQLType(UUID::class.createType())
+        assertNotNull(result)
+        assertEquals(expected = "UUID", actual = result.name)
+    }
+
+    @Test
+    fun `Non valid type returns null`() {
+        val validator: Validator = mockk()
+        val wiringFactory: KotlinDirectiveWiringFactory = mockk()
+        val hooks = CustomSchemaGeneratorHooks(validator, wiringFactory)
+
+        val result = hooks.willGenerateGraphQLType(NonScalar::class.createType())
+        assertNull(result)
+    }
+}