feature: default to creating toJson function instead of a mixin

The default for the `generate_to_json_function` is now `true`.

Author: kevmoo

json_serializable/CHANGELOG.md

@@ -1,5 +1,10 @@
 ## 0.6.0
 
+* **BREAKING** By default, code generated to support `toJson` now creates
+  a top-level function instead of a mixin.
+  * The default for the `generate_to_json_function` is now `true`.
+  * To opt-out of this change, set `generate_to_json_function` to `false`.
+
 * Now supports changing the serialized values of enums using `JsonValue`.
 
   ```dart

json_serializable/README.md

@@ -27,12 +27,13 @@ import 'package:json_annotation/json_annotation.dart';
 part 'example.g.dart';
 
 @JsonSerializable(nullable: false)
-class Person extends Object with _$PersonSerializerMixin {
+class Person {
   final String firstName;
   final String lastName;
   final DateTime dateOfBirth;
   Person({this.firstName, this.lastName, this.dateOfBirth});
   factory Person.fromJson(Map<String, dynamic> json) => _$PersonFromJson(json);
+  Map<String, dynamic> toJson() => _$PersonToJson(this);
 }
 ```
 
@@ -48,16 +49,11 @@ Person _$PersonFromJson(Map<String, dynamic> json) {
       dateOfBirth: DateTime.parse(json['dateOfBirth'] as String));
 }
 
-abstract class _$PersonSerializerMixin {
-  String get firstName;
-  String get lastName;
-  DateTime get dateOfBirth;
-  Map<String, dynamic> toJson() => <String, dynamic>{
-        'firstName': firstName,
-        'lastName': lastName,
-        'dateOfBirth': dateOfBirth.toIso8601String()
-      };
-}
+Map<String, dynamic> _$PersonToJson(Person instance) => <String, dynamic>{
+      'firstName': instance.firstName,
+      'lastName': instance.lastName,
+      'dateOfBirth': instance.dateOfBirth.toIso8601String()
+    };
 ```
 
 # Build configuration
@@ -85,14 +81,14 @@ targets:
           # Options configure how source code is generated for every
           # `@JsonSerializable`-annotated class in the package.
           #
-          # The default value for each of them: `false`.
+          # The default value for each is listed.
           #
           # For usage information, reference the corresponding field in
           # `JsonSerializableGenerator`.
-          use_wrappers: true
-          any_map: true
-          checked: true
-          explicit_to_json: true
+          use_wrappers: false
+          any_map: false
+          checked: false
+          explicit_to_json: false
           generate_to_json_function: true
 ```
 

json_serializable/example/example.dart

@@ -8,10 +8,11 @@ import 'package:json_annotation/json_annotation.dart';
 part 'example.g.dart';
 
 @JsonSerializable(nullable: false)
-class Person extends Object with _$PersonSerializerMixin {
+class Person {
   final String firstName;
   final String lastName;
   final DateTime dateOfBirth;
   Person({this.firstName, this.lastName, this.dateOfBirth});
   factory Person.fromJson(Map<String, dynamic> json) => _$PersonFromJson(json);
+  Map<String, dynamic> toJson() => _$PersonToJson(this);
 }

json_serializable/example/example.g.dart

@@ -17,13 +17,8 @@ Person _$PersonFromJson(Map<String, dynamic> json) {
       dateOfBirth: DateTime.parse(json['dateOfBirth'] as String));
 }
 
-abstract class _$PersonSerializerMixin {
-  String get firstName;
-  String get lastName;
-  DateTime get dateOfBirth;
-  Map<String, dynamic> toJson() => <String, dynamic>{
-        'firstName': firstName,
-        'lastName': lastName,
-        'dateOfBirth': dateOfBirth.toIso8601String()
-      };
-}
+Map<String, dynamic> _$PersonToJson(Person instance) => <String, dynamic>{
+      'firstName': instance.firstName,
+      'lastName': instance.lastName,
+      'dateOfBirth': instance.dateOfBirth.toIso8601String()
+    };

json_serializable/lib/src/json_part_builder.dart

@@ -27,7 +27,7 @@ Builder jsonPartBuilder({
   bool anyMap = false,
   bool checked = false,
   bool explicitToJson = false,
-  bool generateToJsonFunction = false,
+  bool generateToJsonFunction = true,
 }) {
   return new PartBuilder([
     new JsonSerializableGenerator(

json_serializable/lib/src/json_serializable_generator.dart

@@ -95,26 +95,26 @@ class JsonSerializableGenerator
   /// Controls how `toJson` functionality is generated for all types processed
   /// by this generator.
   ///
-  /// If `false` (the default), a private `_$ClassNameSerializerMixin` class is
-  /// created in the generated part file which contains a `toJson` method.
-  ///
-  /// Mix in this class to the source class:
+  /// If `true` (the default), then a top-level function is created that you can reference
+  /// from your class.
   ///
   /// ```dart
   /// @JsonSerializable()
-  /// class Example extends Object with _$ExampleSerializerMixin {
+  /// class Example {
   ///   // ...
+  ///   Map<String, dynamic> toJson() => _$ExampleToJson(this);
   /// }
   /// ```
   ///
-  /// If `true`, then a top-level function is created that you can reference
-  /// from your class.
+  /// If `false`, a private `_$ClassNameSerializerMixin` class is
+  /// created in the generated part file which contains a `toJson` method.
+  ///
+  /// Mix in this class to the source class:
   ///
   /// ```dart
   /// @JsonSerializable()
-  /// class Example {
+  /// class Example extends Object with _$ExampleSerializerMixin {
   ///   // ...
-  ///   Map<String, dynamic> toJson() => _$ExampleToJson(this);
   /// }
   /// ```
   final bool generateToJsonFunction;
@@ -129,12 +129,12 @@ class JsonSerializableGenerator
     bool anyMap = false,
     bool checked = false,
     bool explicitToJson = false,
-    bool generateToJsonFunction = false,
+    bool generateToJsonFunction = true,
   })  : this.useWrappers = useWrappers ?? false,
         this.anyMap = anyMap ?? false,
         this.checked = checked ?? false,
         this.explicitToJson = explicitToJson ?? false,
-        this.generateToJsonFunction = generateToJsonFunction ?? false,
+        this.generateToJsonFunction = generateToJsonFunction ?? true,
         this._typeHelpers = typeHelpers ?? _defaultHelpers;
 
   /// Creates an instance of [JsonSerializableGenerator].

json_serializable/test/config_test.dart

@@ -102,7 +102,7 @@ const _validConfig = const {
   'any_map': true,
   'checked': true,
   'explicit_to_json': true,
-  'generate_to_json_function': true,
+  'generate_to_json_function': false,
 };
 
 const _invalidConfig = const {

json_serializable/test/integration/json_test_example.dart

@@ -11,7 +11,7 @@ import 'json_test_common.dart';
 part 'json_test_example.g.dart';
 
 @JsonSerializable()
-class Person extends Object with _$PersonSerializerMixin {
+class Person {
   final String firstName, middleName, lastName;
   final DateTime dateOfBirth;
   @JsonKey(name: '\$house')
@@ -26,6 +26,8 @@ class Person extends Object with _$PersonSerializerMixin {
 
   factory Person.fromJson(Map<String, dynamic> json) => _$PersonFromJson(json);
 
+  Map<String, dynamic> toJson() => _$PersonToJson(this);
+
   bool operator ==(Object other) =>
       other is Person &&
       firstName == other.firstName &&
@@ -37,7 +39,7 @@ class Person extends Object with _$PersonSerializerMixin {
 }
 
 @JsonSerializable()
-class Order extends Object with _$OrderSerializerMixin {
+class Order {
   /// Used to test that `disallowNullValues: true` forces `includeIfNull: false`
   @JsonKey(disallowNullValue: true)
   int count;
@@ -74,6 +76,8 @@ class Order extends Object with _$OrderSerializerMixin {
 
   factory Order.fromJson(Map<String, dynamic> json) => _$OrderFromJson(json);
 
+  Map<String, dynamic> toJson() => _$OrderToJson(this);
+
   bool operator ==(Object other) =>
       other is Order &&
       count == other.count &&
@@ -83,7 +87,7 @@ class Order extends Object with _$OrderSerializerMixin {
 }
 
 @JsonSerializable()
-class Item extends ItemCore with _$ItemSerializerMixin {
+class Item extends ItemCore {
   @JsonKey(includeIfNull: false, name: 'item-number')
   int itemNumber;
   List<DateTime> saleDates;
@@ -93,6 +97,8 @@ class Item extends ItemCore with _$ItemSerializerMixin {
 
   factory Item.fromJson(Map<String, dynamic> json) => _$ItemFromJson(json);
 
+  Map<String, dynamic> toJson() => _$ItemToJson(this);
+
   bool operator ==(Object other) =>
       other is Item &&
       price == other.price &&
@@ -101,7 +107,7 @@ class Item extends ItemCore with _$ItemSerializerMixin {
 }
 
 @JsonSerializable()
-class Numbers extends Object with _$NumbersSerializerMixin {
+class Numbers {
   List<int> ints;
   List<num> nums;
   List<double> doubles;
@@ -120,6 +126,8 @@ class Numbers extends Object with _$NumbersSerializerMixin {
   factory Numbers.fromJson(Map<String, dynamic> json) =>
       _$NumbersFromJson(json);
 
+  Map<String, dynamic> toJson() => _$NumbersToJson(this);
+
   bool operator ==(Object other) =>
       other is Numbers &&
       deepEquals(ints, other.ints) &&

json_serializable/test/integration/json_test_example.g.dart

@@ -24,25 +24,16 @@ Person _$PersonFromJson(Map<String, dynamic> json) {
         (k, e) => new MapEntry(k, _$enumDecodeNullable(_$CategoryEnumMap, e)));
 }
 
-abstract class _$PersonSerializerMixin {
-  String get firstName;
-  String get middleName;
-  String get lastName;
-  DateTime get dateOfBirth;
-  Category get house;
-  Order get order;
-  Map<String, Category> get houseMap;
-  Map<String, dynamic> toJson() => <String, dynamic>{
-        'firstName': firstName,
-        'middleName': middleName,
-        'lastName': lastName,
-        'dateOfBirth': dateOfBirth?.toIso8601String(),
-        r'$house': _$CategoryEnumMap[house],
-        'order': order,
-        'houseMap':
-            houseMap?.map((k, e) => new MapEntry(k, _$CategoryEnumMap[e]))
-      };
-}
+Map<String, dynamic> _$PersonToJson(Person instance) => <String, dynamic>{
+      'firstName': instance.firstName,
+      'middleName': instance.middleName,
+      'lastName': instance.lastName,
+      'dateOfBirth': instance.dateOfBirth?.toIso8601String(),
+      r'$house': _$CategoryEnumMap[instance.house],
+      'order': instance.order,
+      'houseMap': instance.houseMap
+          ?.map((k, e) => new MapEntry(k, _$CategoryEnumMap[e]))
+    };
 
 T _$enumDecode<T>(Map<T, dynamic> enumValues, dynamic source) {
   if (source == null) {
@@ -95,34 +86,24 @@ Order _$OrderFromJson(Map<String, dynamic> json) {
             StatusCode.success;
 }
 
-abstract class _$OrderSerializerMixin {
-  int get count;
-  bool get isRushed;
-  Category get category;
-  UnmodifiableListView<Item> get items;
-  Platform get platform;
-  Map<String, Platform> get altPlatforms;
-  Uri get homepage;
-  StatusCode get statusCode;
-  Map<String, dynamic> toJson() {
-    var val = <String, dynamic>{};
-
-    void writeNotNull(String key, dynamic value) {
-      if (value != null) {
-        val[key] = value;
-      }
-    }
+Map<String, dynamic> _$OrderToJson(Order instance) {
+  var val = <String, dynamic>{};
 
-    writeNotNull('count', count);
-    val['isRushed'] = isRushed;
-    val['category'] = _$CategoryEnumMap[category];
-    val['items'] = items;
-    val['platform'] = platform;
-    val['altPlatforms'] = altPlatforms;
-    val['homepage'] = homepage?.toString();
-    val['status_code'] = _$StatusCodeEnumMap[statusCode];
-    return val;
+  void writeNotNull(String key, dynamic value) {
+    if (value != null) {
+      val[key] = value;
+    }
   }
+
+  writeNotNull('count', instance.count);
+  val['isRushed'] = instance.isRushed;
+  val['category'] = _$CategoryEnumMap[instance.category];
+  val['items'] = instance.items;
+  val['platform'] = instance.platform;
+  val['altPlatforms'] = instance.altPlatforms;
+  val['homepage'] = instance.homepage?.toString();
+  val['status_code'] = _$StatusCodeEnumMap[instance.statusCode];
+  return val;
 }
 
 const _$StatusCodeEnumMap = const <StatusCode, dynamic>{
@@ -139,27 +120,22 @@ Item _$ItemFromJson(Map<String, dynamic> json) {
     ..rates = (json['rates'] as List)?.map((e) => e as int)?.toList();
 }
 
-abstract class _$ItemSerializerMixin {
-  int get price;
-  int get itemNumber;
-  List<DateTime> get saleDates;
-  List<int> get rates;
-  Map<String, dynamic> toJson() {
-    var val = <String, dynamic>{
-      'price': price,
-    };
+Map<String, dynamic> _$ItemToJson(Item instance) {
+  var val = <String, dynamic>{
+    'price': instance.price,
+  };
 
-    void writeNotNull(String key, dynamic value) {
-      if (value != null) {
-        val[key] = value;
-      }
+  void writeNotNull(String key, dynamic value) {
+    if (value != null) {
+      val[key] = value;
     }
-
-    writeNotNull('item-number', itemNumber);
-    val['saleDates'] = saleDates?.map((e) => e?.toIso8601String())?.toList();
-    val['rates'] = rates;
-    return val;
   }
+
+  writeNotNull('item-number', instance.itemNumber);
+  val['saleDates'] =
+      instance.saleDates?.map((e) => e?.toIso8601String())?.toList();
+  val['rates'] = instance.rates;
+  return val;
 }
 
 Numbers _$NumbersFromJson(Map<String, dynamic> json) {
@@ -177,19 +153,12 @@ Numbers _$NumbersFromJson(Map<String, dynamic> json) {
         json['date'] == null ? null : dateTimeFromEpochUs(json['date'] as int);
 }
 
-abstract class _$NumbersSerializerMixin {
-  List<int> get ints;
-  List<num> get nums;
-  List<double> get doubles;
-  List<double> get nnDoubles;
-  Duration get duration;
-  DateTime get date;
-  Map<String, dynamic> toJson() => <String, dynamic>{
-        'ints': ints,
-        'nums': nums,
-        'doubles': doubles,
-        'nnDoubles': nnDoubles,
-        'duration': duration == null ? null : durationToInt(duration),
-        'date': date == null ? null : dateTimeToEpochUs(date)
-      };
-}
+Map<String, dynamic> _$NumbersToJson(Numbers instance) => <String, dynamic>{
+      'ints': instance.ints,
+      'nums': instance.nums,
+      'doubles': instance.doubles,
+      'nnDoubles': instance.nnDoubles,
+      'duration':
+          instance.duration == null ? null : durationToInt(instance.duration),
+      'date': instance.date == null ? null : dateTimeToEpochUs(instance.date)
+    };