[dart-dio] Fix compile error in enum properties with "default" values (#20495) (#21355)

* [dart-dio] Fix compile error in enum properties with "default" values(#20495)

* Add a test schema with enum properties

modules/openapi-generator/src/main/resources/dart/libraries/dio/serialization/built_value/class_members.mustache

@@ -32,7 +32,7 @@
 
   @BuiltValueHook(initializeBuilder: true)
   static void _defaults({{{classname}}}Builder b) => b{{#vendorExtensions.x-parent-discriminator}}..{{propertyName}}=b.discriminatorValue{{/vendorExtensions.x-parent-discriminator}}{{#vendorExtensions.x-self-and-ancestor-only-props}}{{#defaultValue}}
-      ..{{{name}}} = {{#isEnum}}{{^isContainer}}const {{{enumName}}}._({{/isContainer}}{{/isEnum}}{{{defaultValue}}}{{#isEnum}}{{^isContainer}}){{/isContainer}}{{/isEnum}}{{/defaultValue}}{{/vendorExtensions.x-self-and-ancestor-only-props}};
+      ..{{{name}}} = {{#isEnum}}{{^isContainer}}{{{defaultValue}}}{{/isContainer}}{{/isEnum}}{{^isEnum}}{{{defaultValue}}}{{/isEnum}}{{/defaultValue}}{{/vendorExtensions.x-self-and-ancestor-only-props}};
 
 {{/vendorExtensions.x-is-parent}}  @BuiltValueSerializer(custom: true)
   static Serializer<{{classname}}> get serializer => _${{classname}}Serializer();

modules/openapi-generator/src/test/resources/3_0/dart/petstore-with-fake-endpoints-models-for-testing.yaml

@@ -2062,3 +2062,22 @@ components:
       enum:
         - admin
         - user
+    TestEnum:
+      type: string
+      enum:
+        - ""
+        - "1"
+        - "2"
+      title: TestEnum
+    TestItem:
+      type: object
+      required:
+        - test
+      properties:
+        test:
+          type: integer
+          title: test
+        testEmum:
+          $ref: '#/components/schemas/TestEnum'
+          default: ""
+      title: TestItem

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/.openapi-generator/FILES

@@ -56,7 +56,9 @@ doc/SingleRefType.md
 doc/SpecialModelName.md
 doc/StoreApi.md
 doc/Tag.md
+doc/TestEnum.md
 doc/TestInlineFreeformAdditionalPropertiesRequest.md
+doc/TestItem.md
 doc/User.md
 doc/UserApi.md
 lib/openapi.dart
@@ -122,6 +124,8 @@ lib/src/model/read_only_first.dart
 lib/src/model/single_ref_type.dart
 lib/src/model/special_model_name.dart
 lib/src/model/tag.dart
+lib/src/model/test_enum.dart
 lib/src/model/test_inline_freeform_additional_properties_request.dart
+lib/src/model/test_item.dart
 lib/src/model/user.dart
 pubspec.yaml

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/README.md

@@ -164,7 +164,9 @@ Class | Method | HTTP request | Description
  - [SingleRefType](doc/SingleRefType.md)
  - [SpecialModelName](doc/SpecialModelName.md)
  - [Tag](doc/Tag.md)
+ - [TestEnum](doc/TestEnum.md)
  - [TestInlineFreeformAdditionalPropertiesRequest](doc/TestInlineFreeformAdditionalPropertiesRequest.md)
+ - [TestItem](doc/TestItem.md)
  - [User](doc/User.md)
 
 

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/doc/TestEnum.md

@@ -0,0 +1,14 @@
+# openapi.model.TestEnum
+
+## Load the model package
+```dart
+import 'package:openapi/api.dart';
+```
+
+## Properties
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+
+[[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
+
+

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/doc/TestItem.md

@@ -0,0 +1,16 @@
+# openapi.model.TestItem
+
+## Load the model package
+```dart
+import 'package:openapi/api.dart';
+```
+
+## Properties
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**test** | **int** |  | 
+**testEmum** | [**TestEnum**](TestEnum.md) |  | [optional] 
+
+[[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
+
+

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/openapi.dart

@@ -65,6 +65,8 @@ export 'package:openapi/src/model/read_only_first.dart';
 export 'package:openapi/src/model/single_ref_type.dart';
 export 'package:openapi/src/model/special_model_name.dart';
 export 'package:openapi/src/model/tag.dart';
+export 'package:openapi/src/model/test_enum.dart';
 export 'package:openapi/src/model/test_inline_freeform_additional_properties_request.dart';
+export 'package:openapi/src/model/test_item.dart';
 export 'package:openapi/src/model/user.dart';
 

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/deserialize.dart

@@ -41,6 +41,7 @@ import 'package:openapi/src/model/read_only_first.dart';
 import 'package:openapi/src/model/special_model_name.dart';
 import 'package:openapi/src/model/tag.dart';
 import 'package:openapi/src/model/test_inline_freeform_additional_properties_request.dart';
+import 'package:openapi/src/model/test_item.dart';
 import 'package:openapi/src/model/user.dart';
 
 final _regList = RegExp(r'^List<(.*)>$');
@@ -163,8 +164,13 @@ final _regMap = RegExp(r'^Map<String,(.*)>$');
           return SpecialModelName.fromJson(value as Map<String, dynamic>) as ReturnType;
         case 'Tag':
           return Tag.fromJson(value as Map<String, dynamic>) as ReturnType;
+        case 'TestEnum':
+          
+          
         case 'TestInlineFreeformAdditionalPropertiesRequest':
           return TestInlineFreeformAdditionalPropertiesRequest.fromJson(value as Map<String, dynamic>) as ReturnType;
+        case 'TestItem':
+          return TestItem.fromJson(value as Map<String, dynamic>) as ReturnType;
         case 'User':
           return User.fromJson(value as Map<String, dynamic>) as ReturnType;
         default:

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/test_enum.dart

@@ -0,0 +1,25 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+
+// ignore_for_file: unused_element
+import 'package:json_annotation/json_annotation.dart';
+
+
+enum TestEnum {
+      @JsonValue(r'')
+      empty(r''),
+      @JsonValue(r'1')
+      n1(r'1'),
+      @JsonValue(r'2')
+      n2(r'2'),
+      @JsonValue(r'unknown_default_open_api')
+      unknownDefaultOpenApi(r'unknown_default_open_api');
+
+  const TestEnum(this.value);
+
+  final String value;
+
+  @override
+  String toString() => value;
+}

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/test_item.dart

@@ -0,0 +1,74 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+
+// ignore_for_file: unused_element
+import 'package:openapi/src/model/test_enum.dart';
+import 'package:json_annotation/json_annotation.dart';
+
+part 'test_item.g.dart';
+
+
+@JsonSerializable(
+  checked: true,
+  createToJson: true,
+  disallowUnrecognizedKeys: false,
+  explicitToJson: true,
+)
+class TestItem {
+  /// Returns a new [TestItem] instance.
+  TestItem({
+
+    required  this.test,
+
+     this.testEmum,
+  });
+
+  @JsonKey(
+    
+    name: r'test',
+    required: true,
+    includeIfNull: false,
+  )
+
+
+  final int test;
+
+
+
+  @JsonKey(
+    
+    name: r'testEmum',
+    required: false,
+    includeIfNull: false,
+  unknownEnumValue: TestEnum.unknownDefaultOpenApi,
+  )
+
+
+  final TestEnum? testEmum;
+
+
+
+
+
+    @override
+    bool operator ==(Object other) => identical(this, other) || other is TestItem &&
+      other.test == test &&
+      other.testEmum == testEmum;
+
+    @override
+    int get hashCode =>
+        test.hashCode +
+        testEmum.hashCode;
+
+  factory TestItem.fromJson(Map<String, dynamic> json) => _$TestItemFromJson(json);
+
+  Map<String, dynamic> toJson() => _$TestItemToJson(this);
+
+  @override
+  String toString() {
+    return toJson().toString();
+  }
+
+}
+

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/test/test_enum_test.dart

@@ -0,0 +1,9 @@
+import 'package:test/test.dart';
+import 'package:openapi/openapi.dart';
+
+// tests for TestEnum
+void main() {
+
+  group(TestEnum, () {
+  });
+}

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/test/test_item_test.dart

@@ -0,0 +1,21 @@
+import 'package:test/test.dart';
+import 'package:openapi/openapi.dart';
+
+// tests for TestItem
+void main() {
+  final TestItem? instance = /* TestItem(...) */ null;
+  // TODO add properties to the entity
+
+  group(TestItem, () {
+    // int test
+    test('to test the property `test`', () async {
+      // TODO
+    });
+
+    // TestEnum testEmum
+    test('to test the property `testEmum`', () async {
+      // TODO
+    });
+
+  });
+}

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/.openapi-generator/FILES

@@ -55,7 +55,9 @@ doc/SingleRefType.md
 doc/SpecialModelName.md
 doc/StoreApi.md
 doc/Tag.md
+doc/TestEnum.md
 doc/TestInlineFreeformAdditionalPropertiesRequest.md
+doc/TestItem.md
 doc/User.md
 doc/UserApi.md
 lib/openapi.dart
@@ -123,7 +125,9 @@ lib/src/model/read_only_first.dart
 lib/src/model/single_ref_type.dart
 lib/src/model/special_model_name.dart
 lib/src/model/tag.dart
+lib/src/model/test_enum.dart
 lib/src/model/test_inline_freeform_additional_properties_request.dart
+lib/src/model/test_item.dart
 lib/src/model/user.dart
 lib/src/serializers.dart
 pubspec.yaml

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/README.md

@@ -163,7 +163,9 @@ Class | Method | HTTP request | Description
  - [SingleRefType](doc/SingleRefType.md)
  - [SpecialModelName](doc/SpecialModelName.md)
  - [Tag](doc/Tag.md)
+ - [TestEnum](doc/TestEnum.md)
  - [TestInlineFreeformAdditionalPropertiesRequest](doc/TestInlineFreeformAdditionalPropertiesRequest.md)
+ - [TestItem](doc/TestItem.md)
  - [User](doc/User.md)
 
 

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/doc/TestEnum.md

@@ -0,0 +1,14 @@
+# openapi.model.TestEnum
+
+## Load the model package
+```dart
+import 'package:openapi/api.dart';
+```
+
+## Properties
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+
+[[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
+
+

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/doc/TestItem.md

@@ -0,0 +1,16 @@
+# openapi.model.TestItem
+
+## Load the model package
+```dart
+import 'package:openapi/api.dart';
+```
+
+## Properties
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**test** | **int** |  | 
+**testEmum** | [**TestEnum**](TestEnum.md) |  | [optional] 
+
+[[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
+
+

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/openapi.dart

@@ -66,6 +66,8 @@ export 'package:openapi/src/model/read_only_first.dart';
 export 'package:openapi/src/model/single_ref_type.dart';
 export 'package:openapi/src/model/special_model_name.dart';
 export 'package:openapi/src/model/tag.dart';
+export 'package:openapi/src/model/test_enum.dart';
 export 'package:openapi/src/model/test_inline_freeform_additional_properties_request.dart';
+export 'package:openapi/src/model/test_item.dart';
 export 'package:openapi/src/model/user.dart';
 

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/test_enum.dart

@@ -0,0 +1,38 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+
+// ignore_for_file: unused_element
+import 'package:built_collection/built_collection.dart';
+import 'package:built_value/built_value.dart';
+import 'package:built_value/serializer.dart';
+
+part 'test_enum.g.dart';
+
+class TestEnum extends EnumClass {
+
+  @BuiltValueEnumConst(wireName: r'')
+  static const TestEnum empty = _$empty;
+  @BuiltValueEnumConst(wireName: r'1')
+  static const TestEnum n1 = _$n1;
+  @BuiltValueEnumConst(wireName: r'2')
+  static const TestEnum n2 = _$n2;
+  @BuiltValueEnumConst(wireName: r'unknown_default_open_api', fallback: true)
+  static const TestEnum unknownDefaultOpenApi = _$unknownDefaultOpenApi;
+
+  static Serializer<TestEnum> get serializer => _$testEnumSerializer;
+
+  const TestEnum._(String name): super(name);
+
+  static BuiltSet<TestEnum> get values => _$values;
+  static TestEnum valueOf(String name) => _$valueOf(name);
+}
+
+/// Optionally, enum_class can generate a mixin to go with your enum for use
+/// with Angular. It exposes your enum constants as getters. So, if you mix it
+/// in to your Dart component class, the values become available to the
+/// corresponding Angular template.
+///
+/// Trigger mixin generation by writing a line like this one next to your enum.
+abstract class TestEnumMixin = Object with _$TestEnumMixin;
+

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/test_item.dart

@@ -0,0 +1,126 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+
+// ignore_for_file: unused_element
+import 'package:openapi/src/model/test_enum.dart';
+import 'package:built_value/built_value.dart';
+import 'package:built_value/serializer.dart';
+
+part 'test_item.g.dart';
+
+/// TestItem
+///
+/// Properties:
+/// * [test] 
+/// * [testEmum] 
+@BuiltValue()
+abstract class TestItem implements Built<TestItem, TestItemBuilder> {
+  @BuiltValueField(wireName: r'test')
+  int get test;
+
+  @BuiltValueField(wireName: r'testEmum')
+  TestEnum? get testEmum;
+  // enum testEmumEnum {  ,  1,  2,  };
+
+  TestItem._();
+
+  factory TestItem([void updates(TestItemBuilder b)]) = _$TestItem;
+
+  @BuiltValueHook(initializeBuilder: true)
+  static void _defaults(TestItemBuilder b) => b;
+
+  @BuiltValueSerializer(custom: true)
+  static Serializer<TestItem> get serializer => _$TestItemSerializer();
+}
+
+class _$TestItemSerializer implements PrimitiveSerializer<TestItem> {
+  @override
+  final Iterable<Type> types = const [TestItem, _$TestItem];
+
+  @override
+  final String wireName = r'TestItem';
+
+  Iterable<Object?> _serializeProperties(
+    Serializers serializers,
+    TestItem object, {
+    FullType specifiedType = FullType.unspecified,
+  }) sync* {
+    yield r'test';
+    yield serializers.serialize(
+      object.test,
+      specifiedType: const FullType(int),
+    );
+    if (object.testEmum != null) {
+      yield r'testEmum';
+      yield serializers.serialize(
+        object.testEmum,
+        specifiedType: const FullType(TestEnum),
+      );
+    }
+  }
+
+  @override
+  Object serialize(
+    Serializers serializers,
+    TestItem object, {
+    FullType specifiedType = FullType.unspecified,
+  }) {
+    return _serializeProperties(serializers, object, specifiedType: specifiedType).toList();
+  }
+
+  void _deserializeProperties(
+    Serializers serializers,
+    Object serialized, {
+    FullType specifiedType = FullType.unspecified,
+    required List<Object?> serializedList,
+    required TestItemBuilder result,
+    required List<Object?> unhandled,
+  }) {
+    for (var i = 0; i < serializedList.length; i += 2) {
+      final key = serializedList[i] as String;
+      final value = serializedList[i + 1];
+      switch (key) {
+        case r'test':
+          final valueDes = serializers.deserialize(
+            value,
+            specifiedType: const FullType(int),
+          ) as int;
+          result.test = valueDes;
+          break;
+        case r'testEmum':
+          final valueDes = serializers.deserialize(
+            value,
+            specifiedType: const FullType(TestEnum),
+          ) as TestEnum;
+          result.testEmum = valueDes;
+          break;
+        default:
+          unhandled.add(key);
+          unhandled.add(value);
+          break;
+      }
+    }
+  }
+
+  @override
+  TestItem deserialize(
+    Serializers serializers,
+    Object serialized, {
+    FullType specifiedType = FullType.unspecified,
+  }) {
+    final result = TestItemBuilder();
+    final serializedList = (serialized as Iterable<Object?>).toList();
+    final unhandled = <Object?>[];
+    _deserializeProperties(
+      serializers,
+      serialized,
+      specifiedType: specifiedType,
+      serializedList: serializedList,
+      unhandled: unhandled,
+      result: result,
+    );
+    return result.build();
+  }
+}
+

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/serializers.dart

@@ -62,7 +62,9 @@ import 'package:openapi/src/model/read_only_first.dart';
 import 'package:openapi/src/model/single_ref_type.dart';
 import 'package:openapi/src/model/special_model_name.dart';
 import 'package:openapi/src/model/tag.dart';
+import 'package:openapi/src/model/test_enum.dart';
 import 'package:openapi/src/model/test_inline_freeform_additional_properties_request.dart';
+import 'package:openapi/src/model/test_item.dart';
 import 'package:openapi/src/model/user.dart';
 
 part 'serializers.g.dart';
@@ -116,7 +118,9 @@ part 'serializers.g.dart';
   SingleRefType,
   SpecialModelName,
   Tag,
+  TestEnum,
   TestInlineFreeformAdditionalPropertiesRequest,
+  TestItem,
   User,
 ])
 Serializers serializers = (_$serializers.toBuilder()

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/test/test_enum_test.dart

@@ -0,0 +1,9 @@
+import 'package:test/test.dart';
+import 'package:openapi/openapi.dart';
+
+// tests for TestEnum
+void main() {
+
+  group(TestEnum, () {
+  });
+}

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/test/test_item_test.dart

@@ -0,0 +1,21 @@
+import 'package:test/test.dart';
+import 'package:openapi/openapi.dart';
+
+// tests for TestItem
+void main() {
+  final instance = TestItemBuilder();
+  // TODO add properties to the builder and call build()
+
+  group(TestItem, () {
+    // int test
+    test('to test the property `test`', () async {
+      // TODO
+    });
+
+    // TestEnum testEmum
+    test('to test the property `testEmum`', () async {
+      // TODO
+    });
+
+  });
+}

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/.openapi-generator/FILES

@@ -56,7 +56,9 @@ doc/SingleRefType.md
 doc/SpecialModelName.md
 doc/StoreApi.md
 doc/Tag.md
+doc/TestEnum.md
 doc/TestInlineFreeformAdditionalPropertiesRequest.md
+doc/TestItem.md
 doc/User.md
 doc/UserApi.md
 git_push.sh
@@ -124,6 +126,8 @@ lib/model/read_only_first.dart
 lib/model/single_ref_type.dart
 lib/model/special_model_name.dart
 lib/model/tag.dart
+lib/model/test_enum.dart
 lib/model/test_inline_freeform_additional_properties_request.dart
+lib/model/test_item.dart
 lib/model/user.dart
 pubspec.yaml

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/README.md

@@ -157,7 +157,9 @@ Class | Method | HTTP request | Description
  - [SingleRefType](doc//SingleRefType.md)
  - [SpecialModelName](doc//SpecialModelName.md)
  - [Tag](doc//Tag.md)
+ - [TestEnum](doc//TestEnum.md)
  - [TestInlineFreeformAdditionalPropertiesRequest](doc//TestInlineFreeformAdditionalPropertiesRequest.md)
+ - [TestItem](doc//TestItem.md)
  - [User](doc//User.md)
 
 

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/doc/TestEnum.md

@@ -0,0 +1,14 @@
+# openapi.model.TestEnum
+
+## Load the model package
+```dart
+import 'package:openapi/api.dart';
+```
+
+## Properties
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+
+[[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
+
+

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/doc/TestItem.md

@@ -0,0 +1,16 @@
+# openapi.model.TestItem
+
+## Load the model package
+```dart
+import 'package:openapi/api.dart';
+```
+
+## Properties
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**test** | **int** |  | 
+**testEmum** | [**TestEnum**](TestEnum.md) |  | [optional] 
+
+[[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
+
+

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api.dart

@@ -84,7 +84,9 @@ part 'model/read_only_first.dart';
 part 'model/single_ref_type.dart';
 part 'model/special_model_name.dart';
 part 'model/tag.dart';
+part 'model/test_enum.dart';
 part 'model/test_inline_freeform_additional_properties_request.dart';
+part 'model/test_item.dart';
 part 'model/user.dart';
 
 

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api_client.dart

@@ -278,8 +278,12 @@ class ApiClient {
           return SpecialModelName.fromJson(value);
         case 'Tag':
           return Tag.fromJson(value);
+        case 'TestEnum':
+          return TestEnumTypeTransformer().decode(value);
         case 'TestInlineFreeformAdditionalPropertiesRequest':
           return TestInlineFreeformAdditionalPropertiesRequest.fromJson(value);
+        case 'TestItem':
+          return TestItem.fromJson(value);
         case 'User':
           return User.fromJson(value);
         default:

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api_helper.dart

@@ -73,6 +73,9 @@ String parameterToString(dynamic value) {
   if (value is SingleRefType) {
     return SingleRefTypeTypeTransformer().encode(value).toString();
   }
+  if (value is TestEnum) {
+    return TestEnumTypeTransformer().encode(value).toString();
+  }
   return value.toString();
 }
 

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/model/test_enum.dart

@@ -0,0 +1,88 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+// @dart=2.18
+
+// ignore_for_file: unused_element, unused_import
+// ignore_for_file: always_put_required_named_parameters_first
+// ignore_for_file: constant_identifier_names
+// ignore_for_file: lines_longer_than_80_chars
+
+part of openapi.api;
+
+
+class TestEnum {
+  /// Instantiate a new enum with the provided [value].
+  const TestEnum._(this.value);
+
+  /// The underlying value of this enum member.
+  final String value;
+
+  @override
+  String toString() => value;
+
+  String toJson() => value;
+
+  static const empty = TestEnum._(r'');
+  static const n1 = TestEnum._(r'1');
+  static const n2 = TestEnum._(r'2');
+
+  /// List of all possible values in this [enum][TestEnum].
+  static const values = <TestEnum>[
+    empty,
+    n1,
+    n2,
+  ];
+
+  static TestEnum? fromJson(dynamic value) => TestEnumTypeTransformer().decode(value);
+
+  static List<TestEnum> listFromJson(dynamic json, {bool growable = false,}) {
+    final result = <TestEnum>[];
+    if (json is List && json.isNotEmpty) {
+      for (final row in json) {
+        final value = TestEnum.fromJson(row);
+        if (value != null) {
+          result.add(value);
+        }
+      }
+    }
+    return result.toList(growable: growable);
+  }
+}
+
+/// Transformation class that can [encode] an instance of [TestEnum] to String,
+/// and [decode] dynamic data back to [TestEnum].
+class TestEnumTypeTransformer {
+  factory TestEnumTypeTransformer() => _instance ??= const TestEnumTypeTransformer._();
+
+  const TestEnumTypeTransformer._();
+
+  String encode(TestEnum data) => data.value;
+
+  /// Decodes a [dynamic value][data] to a TestEnum.
+  ///
+  /// If [allowNull] is true and the [dynamic value][data] cannot be decoded successfully,
+  /// then null is returned. However, if [allowNull] is false and the [dynamic value][data]
+  /// cannot be decoded successfully, then an [UnimplementedError] is thrown.
+  ///
+  /// The [allowNull] is very handy when an API changes and a new enum value is added or removed,
+  /// and users are still using an old app with the old code.
+  TestEnum? decode(dynamic data, {bool allowNull = true}) {
+    if (data != null) {
+      switch (data) {
+        case r'': return TestEnum.empty;
+        case r'1': return TestEnum.n1;
+        case r'2': return TestEnum.n2;
+        default:
+          if (!allowNull) {
+            throw ArgumentError('Unknown enum value to decode: $data');
+          }
+      }
+    }
+    return null;
+  }
+
+  /// Singleton [TestEnumTypeTransformer] instance.
+  static TestEnumTypeTransformer? _instance;
+}
+

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/model/test_item.dart

@@ -0,0 +1,126 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+// @dart=2.18
+
+// ignore_for_file: unused_element, unused_import
+// ignore_for_file: always_put_required_named_parameters_first
+// ignore_for_file: constant_identifier_names
+// ignore_for_file: lines_longer_than_80_chars
+
+part of openapi.api;
+
+class TestItem {
+  /// Returns a new [TestItem] instance.
+  TestItem({
+    required this.test,
+    this.testEmum,
+  });
+
+  int test;
+
+  ///
+  /// Please note: This property should have been non-nullable! Since the specification file
+  /// does not include a default value (using the "default:" property), however, the generated
+  /// source code must fall back to having a nullable type.
+  /// Consider adding a "default:" property in the specification file to hide this note.
+  ///
+  TestEnum? testEmum;
+
+  @override
+  bool operator ==(Object other) => identical(this, other) || other is TestItem &&
+    other.test == test &&
+    other.testEmum == testEmum;
+
+  @override
+  int get hashCode =>
+    // ignore: unnecessary_parenthesis
+    (test.hashCode) +
+    (testEmum == null ? 0 : testEmum!.hashCode);
+
+  @override
+  String toString() => 'TestItem[test=$test, testEmum=$testEmum]';
+
+  Map<String, dynamic> toJson() {
+    final json = <String, dynamic>{};
+      json[r'test'] = this.test;
+    if (this.testEmum != null) {
+      json[r'testEmum'] = this.testEmum;
+    } else {
+      json[r'testEmum'] = null;
+    }
+    return json;
+  }
+
+  /// Returns a new [TestItem] instance and imports its values from
+  /// [value] if it's a [Map], null otherwise.
+  // ignore: prefer_constructors_over_static_methods
+  static TestItem? fromJson(dynamic value) {
+    if (value is Map) {
+      final json = value.cast<String, dynamic>();
+
+      // Ensure that the map contains the required keys.
+      // Note 1: the values aren't checked for validity beyond being non-null.
+      // Note 2: this code is stripped in release mode!
+      assert(() {
+        requiredKeys.forEach((key) {
+          assert(json.containsKey(key), 'Required key "TestItem[$key]" is missing from JSON.');
+          assert(json[key] != null, 'Required key "TestItem[$key]" has a null value in JSON.');
+        });
+        return true;
+      }());
+
+      return TestItem(
+        test: mapValueOfType<int>(json, r'test')!,
+        testEmum: TestEnum.fromJson(json[r'testEmum']),
+      );
+    }
+    return null;
+  }
+
+  static List<TestItem> listFromJson(dynamic json, {bool growable = false,}) {
+    final result = <TestItem>[];
+    if (json is List && json.isNotEmpty) {
+      for (final row in json) {
+        final value = TestItem.fromJson(row);
+        if (value != null) {
+          result.add(value);
+        }
+      }
+    }
+    return result.toList(growable: growable);
+  }
+
+  static Map<String, TestItem> mapFromJson(dynamic json) {
+    final map = <String, TestItem>{};
+    if (json is Map && json.isNotEmpty) {
+      json = json.cast<String, dynamic>(); // ignore: parameter_assignments
+      for (final entry in json.entries) {
+        final value = TestItem.fromJson(entry.value);
+        if (value != null) {
+          map[entry.key] = value;
+        }
+      }
+    }
+    return map;
+  }
+
+  // maps a json object with a list of TestItem-objects as value to a dart map
+  static Map<String, List<TestItem>> mapListFromJson(dynamic json, {bool growable = false,}) {
+    final map = <String, List<TestItem>>{};
+    if (json is Map && json.isNotEmpty) {
+      // ignore: parameter_assignments
+      json = json.cast<String, dynamic>();
+      for (final entry in json.entries) {
+        map[entry.key] = TestItem.listFromJson(entry.value, growable: growable,);
+      }
+    }
+    return map;
+  }
+
+  /// The list of required keys that must be present in a JSON.
+  static const requiredKeys = <String>{
+    'test',
+  };
+}
+

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/test/test_enum_test.dart

@@ -0,0 +1,21 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+// @dart=2.18
+
+// ignore_for_file: unused_element, unused_import
+// ignore_for_file: always_put_required_named_parameters_first
+// ignore_for_file: constant_identifier_names
+// ignore_for_file: lines_longer_than_80_chars
+
+import 'package:openapi/api.dart';
+import 'package:test/test.dart';
+
+// tests for TestEnum
+void main() {
+
+  group('test TestEnum', () {
+
+  });
+
+}

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/test/test_item_test.dart

@@ -0,0 +1,32 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+// @dart=2.18
+
+// ignore_for_file: unused_element, unused_import
+// ignore_for_file: always_put_required_named_parameters_first
+// ignore_for_file: constant_identifier_names
+// ignore_for_file: lines_longer_than_80_chars
+
+import 'package:openapi/api.dart';
+import 'package:test/test.dart';
+
+// tests for TestItem
+void main() {
+  // final instance = TestItem();
+
+  group('test TestItem', () {
+    // int test
+    test('to test the property `test`', () async {
+      // TODO
+    });
+
+    // TestEnum testEmum
+    test('to test the property `testEmum`', () async {
+      // TODO
+    });
+
+
+  });
+
+}