Add enum_field_rename option in build.yaml for default enum value renaming

json_annotation/lib/src/json_serializable.dart

@@ -168,6 +168,12 @@ class JsonSerializable {
   /// fields annotated with [JsonKey].
   final FieldRename? fieldRename;
 
+  /// Default field rename for enum values when not set on [JsonEnum].
+  ///
+  /// Only applies when configured via `build.yaml`; has no effect when set on
+  /// [JsonSerializable] annotations in source code.
+  final FieldRename? enumFieldRename;
+
   /// When `true` on classes with type parameters (generic types), extra
   /// "helper" parameters will be generated for `fromJson` and/or `toJson` to
   /// support serializing values of those types.
@@ -278,6 +284,7 @@ class JsonSerializable {
     this.disallowUnrecognizedKeys,
     this.explicitToJson,
     this.fieldRename,
+    this.enumFieldRename,
     this.ignoreUnannotated,
     this.includeIfNull,
     this.converters,
@@ -300,6 +307,7 @@ class JsonSerializable {
     disallowUnrecognizedKeys: false,
     explicitToJson: false,
     fieldRename: FieldRename.none,
+    enumFieldRename: FieldRename.none,
     ignoreUnannotated: false,
     includeIfNull: true,
     genericArgumentFactories: false,
@@ -321,6 +329,7 @@ class JsonSerializable {
         disallowUnrecognizedKeys ?? defaults.disallowUnrecognizedKeys,
     explicitToJson: explicitToJson ?? defaults.explicitToJson,
     fieldRename: fieldRename ?? defaults.fieldRename,
+    enumFieldRename: enumFieldRename ?? defaults.enumFieldRename,
     ignoreUnannotated: ignoreUnannotated ?? defaults.ignoreUnannotated,
     includeIfNull: includeIfNull ?? defaults.includeIfNull,
     genericArgumentFactories:

json_serializable/README.md

@@ -321,6 +321,7 @@ targets:
           create_to_json: true
           disallow_unrecognized_keys: false
           explicit_to_json: false
+          enum_field_rename: none
           field_rename: none
           generic_argument_factories: false
           ignore_unannotated: false

json_serializable/lib/src/encoder_helper.dart

@@ -174,7 +174,10 @@ mixin EncodeHelper implements HelperCore {
     // We can consider enums as kinda like having custom converters
     // same rules apply. If `null` is in the set of encoded values, we
     // should not write naive
-    final enumWithNullValue = enumFieldWithNullInEncodeMap(field.type);
+    final enumWithNullValue = enumFieldWithNullInEncodeMap(
+      field.type,
+      defaultEnumFieldRename: config.enumFieldRename,
+    );
     if (enumWithNullValue != null) {
       return !enumWithNullValue;
     }

json_serializable/lib/src/enum_utils.dart

@@ -19,8 +19,14 @@ String constMapName(DartType targetType) =>
 ///
 /// Otherwise, returns `true` if [targetType] is nullable OR if one of the
 /// encoded values of the enum is `null`.
-bool? enumFieldWithNullInEncodeMap(DartType targetType) {
-  final enumMap = _enumMap(targetType);
+bool? enumFieldWithNullInEncodeMap(
+  DartType targetType, {
+  FieldRename? defaultEnumFieldRename,
+}) {
+  final enumMap = _enumMap(
+    targetType,
+    defaultEnumFieldRename: defaultEnumFieldRename,
+  );
 
   if (enumMap == null) return null;
 
@@ -34,10 +40,12 @@ bool? enumFieldWithNullInEncodeMap(DartType targetType) {
 String? enumValueMapFromType(
   DartType targetType, {
   bool nullWithNoAnnotation = false,
+  FieldRename? defaultEnumFieldRename,
 }) {
   final enumMap = _enumMap(
     targetType,
     nullWithNoAnnotation: nullWithNoAnnotation,
+    defaultEnumFieldRename: defaultEnumFieldRename,
   );
 
   if (enumMap == null) return null;
@@ -56,6 +64,7 @@ String? enumValueMapFromType(
 Map<FieldElement, Object?>? _enumMap(
   DartType targetType, {
   bool nullWithNoAnnotation = false,
+  FieldRename? defaultEnumFieldRename,
 }) {
   final targetTypeElement = targetType.element;
   if (targetTypeElement == null) return null;
@@ -74,6 +83,7 @@ Map<FieldElement, Object?>? _enumMap(
         field: field,
         jsonEnum: jsonEnum,
         targetType: targetType,
+        defaultEnumFieldRename: defaultEnumFieldRename,
       ),
   };
 }
@@ -82,6 +92,7 @@ Object? _generateEntry({
   required FieldElement field,
   required JsonEnum jsonEnum,
   required DartType targetType,
+  FieldRename? defaultEnumFieldRename,
 }) {
   final annotation = const TypeChecker.typeNamed(
     JsonValue,
@@ -91,8 +102,6 @@ Object? _generateEntry({
   if (annotation == null) {
     final valueField = jsonEnum.valueField;
     if (valueField != null) {
-      // TODO: fieldRename is pointless here!!! At least log a warning!
-
       final fieldElementType = field.type.element as EnumElement;
 
       final e = fieldElementType.getField(valueField);
@@ -125,7 +134,10 @@ Object? _generateEntry({
         );
       }
     } else {
-      return encodedFieldName(jsonEnum.fieldRename, field.name!);
+      final effectiveRename = jsonEnum.fieldRename != FieldRename.none
+          ? jsonEnum.fieldRename
+          : (defaultEnumFieldRename ?? FieldRename.none);
+      return encodedFieldName(effectiveRename, field.name!);
     }
   } else {
     final reader = ConstantReader(annotation);

json_serializable/lib/src/json_enum_generator.dart

@@ -8,9 +8,12 @@ import 'package:json_annotation/json_annotation.dart';
 import 'package:source_gen/source_gen.dart';
 
 import 'enum_utils.dart';
+import 'settings.dart';
 
 class JsonEnumGenerator extends GeneratorForAnnotation<JsonEnum> {
-  const JsonEnumGenerator() : super(inPackage: 'json_annotation');
+  JsonEnumGenerator(this._settings) : super(inPackage: 'json_annotation');
+
+  final Settings _settings;
 
   @override
   List<String> generateForAnnotatedElement(
@@ -28,6 +31,7 @@ class JsonEnumGenerator extends GeneratorForAnnotation<JsonEnum> {
     final value = enumValueMapFromType(
       element.thisType,
       nullWithNoAnnotation: true,
+      defaultEnumFieldRename: _settings.config.enumFieldRename,
     );
 
     return [?value];

json_serializable/lib/src/json_part_builder.dart

@@ -29,7 +29,7 @@ Builder jsonPartBuilder({
     [
       _UnifiedGenerator([
         JsonSerializableGenerator.fromSettings(settings),
-        const JsonEnumGenerator(),
+        JsonEnumGenerator(settings),
       ]),
       const JsonLiteralGenerator(),
     ],

json_serializable/lib/src/type_helpers/config_types.dart

@@ -64,6 +64,7 @@ class ClassConfig {
   final bool disallowUnrecognizedKeys;
   final bool explicitToJson;
   final FieldRename fieldRename;
+  final FieldRename enumFieldRename;
   final bool genericArgumentFactories;
   final bool ignoreUnannotated;
   final bool includeIfNull;
@@ -83,6 +84,7 @@ class ClassConfig {
     required this.disallowUnrecognizedKeys,
     required this.explicitToJson,
     required this.fieldRename,
+    required this.enumFieldRename,
     required this.genericArgumentFactories,
     required this.ignoreUnannotated,
     required this.includeIfNull,
@@ -118,6 +120,8 @@ class ClassConfig {
             config.genericArgumentFactories ??
             ClassConfig.defaults.genericArgumentFactories,
         fieldRename: config.fieldRename ?? ClassConfig.defaults.fieldRename,
+        enumFieldRename:
+            config.enumFieldRename ?? ClassConfig.defaults.enumFieldRename,
         disallowUnrecognizedKeys:
             config.disallowUnrecognizedKeys ??
             ClassConfig.defaults.disallowUnrecognizedKeys,
@@ -139,6 +143,7 @@ class ClassConfig {
     disallowUnrecognizedKeys: false,
     explicitToJson: false,
     fieldRename: FieldRename.none,
+    enumFieldRename: FieldRename.none,
     genericArgumentFactories: false,
     ignoreUnannotated: false,
     includeIfNull: true,
@@ -159,6 +164,7 @@ class ClassConfig {
     includeIfNull: includeIfNull,
     genericArgumentFactories: genericArgumentFactories,
     fieldRename: fieldRename,
+    enumFieldRename: enumFieldRename,
     disallowUnrecognizedKeys: disallowUnrecognizedKeys,
     // TODO typeConverters = []
   );

json_serializable/lib/src/type_helpers/enum_helper.dart

@@ -21,7 +21,10 @@ class EnumHelper extends TypeHelper<TypeHelperContextWithConfig> {
     String expression,
     TypeHelperContextWithConfig context,
   ) {
-    final memberContent = enumValueMapFromType(targetType);
+    final memberContent = enumValueMapFromType(
+      targetType,
+      defaultEnumFieldRename: context.config.enumFieldRename,
+    );
 
     if (memberContent == null) {
       return null;
@@ -30,7 +33,10 @@ class EnumHelper extends TypeHelper<TypeHelperContextWithConfig> {
     context.addMember(memberContent);
 
     if (targetType.isNullableType ||
-        enumFieldWithNullInEncodeMap(targetType) == true) {
+        enumFieldWithNullInEncodeMap(
+          targetType,
+          defaultEnumFieldRename: context.config.enumFieldRename,
+        ) == true) {
       return '${constMapName(targetType)}[$expression]';
     } else {
       return '${constMapName(targetType)}[$expression]!';
@@ -44,7 +50,10 @@ class EnumHelper extends TypeHelper<TypeHelperContextWithConfig> {
     TypeHelperContextWithConfig context,
     bool defaultProvided,
   ) {
-    final memberContent = enumValueMapFromType(targetType);
+    final memberContent = enumValueMapFromType(
+      targetType,
+      defaultEnumFieldRename: context.config.enumFieldRename,
+    );
 
     if (memberContent == null) {
       return null;

json_serializable/lib/src/utils.dart

@@ -70,6 +70,7 @@ JsonSerializable _valueForAnnotation(ConstantReader reader) => JsonSerializable(
       reader.read('disallowUnrecognizedKeys').literalValue as bool?,
   explicitToJson: reader.read('explicitToJson').literalValue as bool?,
   fieldRename: readEnum(reader.read('fieldRename'), FieldRename.values),
+  enumFieldRename: readEnum(reader.read('enumFieldRename'), FieldRename.values),
   genericArgumentFactories:
       reader.read('genericArgumentFactories').literalValue as bool?,
   ignoreUnannotated: reader.read('ignoreUnannotated').literalValue as bool?,
@@ -120,6 +121,7 @@ ClassConfig mergeConfig(
         annotation.disallowUnrecognizedKeys ?? config.disallowUnrecognizedKeys,
     explicitToJson: annotation.explicitToJson ?? config.explicitToJson,
     fieldRename: annotation.fieldRename ?? config.fieldRename,
+    enumFieldRename: annotation.enumFieldRename ?? config.enumFieldRename,
     genericArgumentFactories:
         annotation.genericArgumentFactories ??
         (classElement.typeParameters.isNotEmpty &&

json_serializable/test/config_test.dart

@@ -136,6 +136,9 @@ void main() {
 
         String lastLine;
         lastLine = switch (entry.key) {
+          'enum_field_rename' =>
+            '`42` is not one of the supported values: none, kebab, snake, '
+                'pascal, screamingSnake',
           'field_rename' =>
             '`42` is not one of the supported values: none, kebab, snake, '
                 'pascal, screamingSnake',
@@ -177,6 +180,7 @@ const _invalidConfig = {
   'create_per_field_to_json': 42,
   'create_to_json': 42,
   'disallow_unrecognized_keys': 42,
+  'enum_field_rename': 42,
   'explicit_to_json': 42,
   'field_rename': 42,
   'generic_argument_factories': 42,

json_serializable/test/json_serializable_test.dart

@@ -6,6 +6,7 @@
 library;
 
 import 'package:json_serializable/json_serializable.dart';
+import 'package:json_serializable/src/settings.dart';
 import 'package:path/path.dart' as p;
 import 'package:source_gen_test/source_gen_test.dart';
 import 'package:test/test.dart';
@@ -41,7 +42,7 @@ Future<void> main() async {
 
   testAnnotatedElements(
     jsonEnumTestReader,
-    const JsonEnumGenerator(),
+    JsonEnumGenerator(Settings()),
     expectedAnnotatedTests: {
       'EnumValueIssue1147',
       'EnumValueNotAField',

json_serializable/test/shared_config.dart

@@ -24,6 +24,7 @@ final generatorConfigNonDefaultJson = Map<String, dynamic>.unmodifiable(
     createPerFieldToJson: true,
     disallowUnrecognizedKeys: true,
     explicitToJson: true,
+    enumFieldRename: FieldRename.pascal,
     fieldRename: FieldRename.kebab,
     ignoreUnannotated: true,
     includeIfNull: false,

json_serializable/test/test_sources/test_sources.dart

@@ -19,6 +19,7 @@ class ConfigurationImplicitDefaults {
   createJsonKeys: false,
   createPerFieldToJson: false,
   disallowUnrecognizedKeys: false,
+  enumFieldRename: FieldRename.none,
   explicitToJson: false,
   fieldRename: FieldRename.none,
   ignoreUnannotated: false,

json_serializable/tool/readme/readme_template.md

@@ -178,6 +178,7 @@ targets:
           create_to_json: true
           disallow_unrecognized_keys: false
           explicit_to_json: false
+          enum_field_rename: none
           field_rename: none
           generic_argument_factories: false
           ignore_unannotated: false