feat: make hybrid classes more flexible by default (#70)

Author: danadajian

src/definitions/object.ts

@@ -69,13 +69,13 @@ export function buildObjectTypeDefinition(
       node.fields?.some((fieldNode) => fieldNode.arguments?.length),
   );
   if (shouldGenerateFunctions) {
-    const fieldsWithNoArguments = node.fields?.filter(
+    const atLeastOneFieldHasNoArguments = node.fields?.some(
       (fieldNode) => !fieldNode.arguments?.length,
     );
     const constructor =
-      !typeInResolverInterfacesConfig && fieldsWithNoArguments?.length
-        ? `(\n${fieldsWithNoArguments
-            .map((fieldNode) => {
+      !typeInResolverInterfacesConfig && atLeastOneFieldHasNoArguments
+        ? `(\n${node.fields
+            ?.map((fieldNode) => {
               const typeMetadata = buildTypeMetadata(
                 fieldNode.type,
                 schema,
@@ -87,6 +87,8 @@ export function buildObjectTypeDefinition(
                 schema,
                 config,
                 typeMetadata,
+                shouldGenerateFunctions,
+                true,
               );
             })
             .join(",\n")}\n)`

src/helpers/build-field-definition.ts

@@ -32,9 +32,18 @@ export function buildFieldDefinition(
   config: CodegenConfigWithDefaults,
   typeMetadata: TypeMetadata,
   shouldGenerateFunctions?: boolean,
+  isConstructorField?: boolean,
 ) {
-  const modifier = buildFieldModifier(node, fieldNode, schema, config);
-  const fieldArguments = buildFieldArguments(node, fieldNode, schema, config);
+  const modifier = buildFieldModifier(
+    node,
+    fieldNode,
+    schema,
+    config,
+    isConstructorField,
+  );
+  const fieldArguments = isConstructorField
+    ? ""
+    : buildFieldArguments(node, fieldNode, schema, config);
   const fieldDefinition = `${modifier} ${fieldNode.name.value}${fieldArguments}`;
   const annotations = buildAnnotations({
     config,
@@ -49,19 +58,28 @@ export function buildFieldDefinition(
     );
   }
 
-  const notImplementedError = ` = throw NotImplementedError("${node.name.value}.${fieldNode.name.value} must be implemented.")`;
-  const defaultFunctionValue = `${typeMetadata.isNullable ? "?" : ""}${notImplementedError}`;
-  const defaultValue = shouldGenerateFunctions
-    ? defaultFunctionValue
-    : typeMetadata.defaultValue;
-  const defaultDefinition = `${typeMetadata.typeName}${defaultValue}`;
+  const notImplementedError = `throw NotImplementedError("${node.name.value}.${fieldNode.name.value} must be implemented.")`;
+  const atLeastOneFieldHasNoArguments = node.fields?.some(
+    (fieldNode) => !fieldNode.arguments?.length,
+  );
   const typeInResolverInterfacesConfig = findTypeInResolverInterfacesConfig(
     node,
     config,
   );
+  const defaultImplementation =
+    !typeInResolverInterfacesConfig && atLeastOneFieldHasNoArguments
+      ? fieldNode.name.value
+      : notImplementedError;
+  const defaultFunctionValue = `${typeMetadata.isNullable ? "?" : ""} = ${defaultImplementation}`;
+  const defaultValue =
+    shouldGenerateFunctions && !isConstructorField
+      ? defaultFunctionValue
+      : typeMetadata.defaultValue;
+  const defaultDefinition = `${typeMetadata.typeName}${defaultValue}`;
+
   const isCompletableFuture =
     typeInResolverInterfacesConfig?.classMethods === "COMPLETABLE_FUTURE";
-  const completableFutureDefinition = `java.util.concurrent.CompletableFuture<${typeMetadata.typeName}${typeMetadata.isNullable ? "?" : ""}>${notImplementedError}`;
+  const completableFutureDefinition = `java.util.concurrent.CompletableFuture<${typeMetadata.typeName}${typeMetadata.isNullable ? "?" : ""}> = ${defaultImplementation}`;
   const field = indent(
     `${fieldDefinition}: ${isCompletableFuture ? completableFutureDefinition : defaultDefinition}`,
     2,
@@ -74,6 +92,7 @@ function buildFieldModifier(
   fieldNode: FieldDefinitionNode,
   schema: GraphQLSchema,
   config: CodegenConfigWithDefaults,
+  isConstructorField?: boolean,
 ) {
   const typeInResolverInterfacesConfig = findTypeInResolverInterfacesConfig(
     node,
@@ -84,6 +103,10 @@ function buildFieldModifier(
     fieldNode,
     schema,
   );
+
+  if (isConstructorField && fieldNode.arguments?.length) {
+    return "private val";
+  }
   if (!typeInResolverInterfacesConfig && !fieldNode.arguments?.length) {
     return shouldOverrideField ? "override val" : "val";
   }

test/integration/Query.kt

@@ -5,5 +5,10 @@ import graphql.schema.DataFetchingEnvironment
 import test.integration.Query as QueryInterface
 
 class IntegrationTestQuery() : Query, QueryInterface() {
-    override fun testQuery(dataFetchingEnvironment: DataFetchingEnvironment): SomeType = SomeType()
+    override fun testQuery1(dataFetchingEnvironment: DataFetchingEnvironment): SomeType = SomeType()
+    override fun testQuery2(dataFetchingEnvironment: DataFetchingEnvironment): SomeHybridType =
+        SomeHybridType(
+            someField = "test",
+            someField2 = "test"
+        )
 }

test/integration/expected.graphql

@@ -30,7 +30,13 @@ directive @specifiedBy(
   ) on SCALAR
 
 type Query {
-  testQuery: SomeType!
+  testQuery1: SomeType!
+  testQuery2: SomeHybridType!
+}
+
+type SomeHybridType {
+  someField: String!
+  someField2(input: String!): String
 }
 
 type SomeType {

test/unit/should_generate_classes_for_types_with_field_args/expected.kt

@@ -11,10 +11,12 @@ open class TypeWithOnlyFieldArgs {
 @GraphQLValidObjectLocations(locations = [GraphQLValidObjectLocations.Locations.OBJECT])
 open class HybridType(
     val nullableField: String? = null,
-    val nonNullableField: String
+    val nonNullableField: String,
+    private val nullableResolver: String? = null,
+    private val nonNullableResolver: String
 ) {
-    open fun nullableResolver(arg: String, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String? = throw NotImplementedError("HybridType.nullableResolver must be implemented.")
-    open fun nonNullableResolver(arg: InputTypeForResolver, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String = throw NotImplementedError("HybridType.nonNullableResolver must be implemented.")
+    open fun nullableResolver(arg: String, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String? = nullableResolver
+    open fun nonNullableResolver(arg: InputTypeForResolver, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String = nonNullableResolver
 }
 
 @GraphQLValidObjectLocations(locations = [GraphQLValidObjectLocations.Locations.INPUT_OBJECT])
@@ -36,8 +38,10 @@ open class TypeImplementingInterface(
     val booleanField1: Boolean? = null,
     val booleanField2: Boolean = false,
     val integerField1: Int? = null,
-    val integerField2: Int
+    val integerField2: Int,
+    private val nullableListResolver: List<String?>? = null,
+    private val nonNullableListResolver: List<String> = emptyList()
 ) : HybridInterface {
-    override fun nullableListResolver(arg1: Int?, arg2: Int, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): List<String?>? = throw NotImplementedError("TypeImplementingInterface.nullableListResolver must be implemented.")
-    override fun nonNullableListResolver(arg1: Int, arg2: Int?, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): List<String> = throw NotImplementedError("TypeImplementingInterface.nonNullableListResolver must be implemented.")
+    override fun nullableListResolver(arg1: Int?, arg2: Int, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): List<String?>? = nullableListResolver
+    override fun nonNullableListResolver(arg1: Int, arg2: Int?, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): List<String> = nonNullableListResolver
 }

test/unit/should_honor_resolverInterfaces_config/expected.kt

@@ -4,14 +4,22 @@ import com.expediagroup.graphql.generator.annotations.*
 
 @GraphQLValidObjectLocations(locations = [GraphQLValidObjectLocations.Locations.OBJECT])
 open class MyIncludedResolverType {
-    open fun nullableField(dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String? = throw NotImplementedError("MyIncludedResolverType.nullableField must be implemented.")
+    open fun nullableField(dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): MyChildType? = throw NotImplementedError("MyIncludedResolverType.nullableField must be implemented.")
     open fun nonNullableField(dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String = throw NotImplementedError("MyIncludedResolverType.nonNullableField must be implemented.")
     open fun nullableResolver(arg: String, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String? = throw NotImplementedError("MyIncludedResolverType.nullableResolver must be implemented.")
     open fun nonNullableResolver(arg: String, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String = throw NotImplementedError("MyIncludedResolverType.nonNullableResolver must be implemented.")
     open fun nullableListResolver(arg1: Int? = null, arg2: Int, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): List<String?>? = throw NotImplementedError("MyIncludedResolverType.nullableListResolver must be implemented.")
     open fun nonNullableListResolver(arg1: Int, arg2: Int? = null, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): List<String> = throw NotImplementedError("MyIncludedResolverType.nonNullableListResolver must be implemented.")
 }
 
+@GraphQLValidObjectLocations(locations = [GraphQLValidObjectLocations.Locations.OBJECT])
+open class MyChildType(
+    val field: String? = null,
+    private val field2: String? = null
+) {
+    open fun field2(arg: String, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String? = field2
+}
+
 @GraphQLValidObjectLocations(locations = [GraphQLValidObjectLocations.Locations.OBJECT])
 open class MyIncludedResolverTypeWithNoFieldArgs {
     open fun nullableField(dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String? = throw NotImplementedError("MyIncludedResolverTypeWithNoFieldArgs.nullableField must be implemented.")

test/unit/should_honor_resolverInterfaces_config/schema.graphql

@@ -1,12 +1,17 @@
 type MyIncludedResolverType {
-  nullableField: String
+  nullableField: MyChildType
   nonNullableField: String!
   nullableResolver(arg: String!): String
   nonNullableResolver(arg: String!): String!
   nullableListResolver(arg1: Int, arg2: Int!): [String]
   nonNullableListResolver(arg1: Int!, arg2: Int): [String!]!
 }
 
+type MyChildType {
+  field: String
+  field2(arg: String!): String
+}
+
 type MyIncludedResolverTypeWithNoFieldArgs {
   nullableField: String
   nonNullableField: String!

test/unit/should_replace_federation_directives/expected.kt

@@ -14,8 +14,9 @@ data class FederatedType(
 @com.expediagroup.graphql.generator.federation.directives.KeyDirective(com.expediagroup.graphql.generator.federation.directives.FieldSet("some other field"))
 @GraphQLValidObjectLocations(locations = [GraphQLValidObjectLocations.Locations.OBJECT])
 open class FederatedTypeResolver(
+    private val field: String,
     @com.expediagroup.graphql.generator.federation.directives.ExternalDirective
     val field2: String? = null
 ) {
-    open fun field(arg: String, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String = throw NotImplementedError("FederatedTypeResolver.field must be implemented.")
+    open fun field(arg: String, dataFetchingEnvironment: graphql.schema.DataFetchingEnvironment): String = field
 }