Clarify nullable

json_serializable/CHANGELOG.md

@@ -1,3 +1,9 @@
+## 0.2.6
+
+* Make `null` field handling smarter. If a field is classified as not
+  `nullable`, then use this knowledge when generating serialization code –  even
+  if `includeIfNull` is `false`.
+
 ## 0.2.5
 
 * Throw an exception if a duplicate JSON key is detected.

json_serializable/lib/src/json_serializable_generator.dart

@@ -139,8 +139,11 @@ class JsonSerializableGenerator
       }
 
       buffer.writeln('  Map<String, dynamic> toJson() ');
-      if (fieldsList
-          .every((e) => _includeIfNull(e, classAnnotation.includeIfNull))) {
+
+      var writeNaive =
+          fieldsList.every((e) => _writeJsonValueNaive(e, classAnnotation));
+
+      if (writeNaive) {
         // write simple `toJson` method that includes all keys...
         _writeToJsonSimple(buffer, fields.values, classAnnotation.nullable);
       } else {
@@ -180,7 +183,7 @@ class JsonSerializableGenerator
 
       var expression = _serializeField(field, classAnnotation.nullable,
           accessOverride: safeFieldAccess);
-      if (_includeIfNull(field, classAnnotation.includeIfNull)) {
+      if (_writeJsonValueNaive(field, classAnnotation)) {
         if (directWrite) {
           buffer.writeln('$safeJsonKeyString : $expression,');
         } else {
@@ -395,8 +398,17 @@ String _safeNameAccess(FieldElement field) {
 bool _nullable(FieldElement field, bool parentValue) =>
     _jsonKeyFor(field).nullable ?? parentValue;
 
-bool _includeIfNull(FieldElement field, bool parentValue) =>
-    _jsonKeyFor(field).includeIfNull ?? parentValue;
+/// Returns `true` if the field can be written to JSON 'naively' – meaning
+/// we can avoid checking for `null`.
+///
+/// `true` if either:
+///   `includeIfNull` is `true`
+///   or
+///   `nullable` is `false`.
+bool _writeJsonValueNaive(
+        FieldElement field, JsonSerializable parentAnnotation) =>
+    (_jsonKeyFor(field).includeIfNull ?? parentAnnotation.includeIfNull) ||
+    !_nullable(field, parentAnnotation.nullable);
 
 JsonKey _jsonKeyFor(FieldElement element) {
   var key = _jsonKeyExpando[element];

json_serializable/test/test_files/json_test_example.dart

@@ -1,9 +1,9 @@
-// Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // ignore_for_file: annotate_overrides, hash_and_equals
-library json_serializable.test.example;
+library json_serializable.test.json_test_example;
 
 import 'dart:collection';
 

json_serializable/test/test_files/json_test_example.g.dart

@@ -4,7 +4,7 @@
 
 // GENERATED CODE - DO NOT MODIFY BY HAND
 
-part of json_serializable.test.example;
+part of json_serializable.test.json_test_example;
 
 // **************************************************************************
 // Generator: JsonSerializableGenerator

json_serializable/test/test_files/json_test_example.non_nullable.dart

@@ -0,0 +1,135 @@
+// Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+// **************************************************************************
+// Generator: _NonNullableGenerator
+// **************************************************************************
+
+// ignore_for_file: annotate_overrides, hash_and_equals
+library json_serializable.test.json_test_example_non_nullable;
+
+import 'dart:collection';
+
+import 'package:collection/collection.dart';
+import 'package:json_annotation/json_annotation.dart';
+
+part 'json_test_example.non_nullable.g.dart';
+
+enum House { gryffindor, hufflepuff, ravenclaw, slytherin }
+
+@JsonSerializable(nullable: false)
+class Person extends Object with _$PersonSerializerMixin {
+  final String firstName, middleName, lastName;
+  final DateTime dateOfBirth;
+  @JsonKey(name: '\$house')
+  final House house;
+
+  Person(this.firstName, this.lastName, this.house,
+      {this.middleName, this.dateOfBirth});
+
+  factory Person.fromJson(Map<String, dynamic> json) => _$PersonFromJson(json);
+
+  bool operator ==(Object other) =>
+      other is Person &&
+      firstName == other.firstName &&
+      middleName == other.middleName &&
+      lastName == other.lastName &&
+      dateOfBirth == other.dateOfBirth &&
+      house == other.house;
+}
+
+enum Category { top, bottom, strange, charmed, up, down }
+
+@JsonSerializable(nullable: false)
+class Order extends Object with _$OrderSerializerMixin {
+  int count;
+  bool isRushed;
+
+  @JsonKey(nullable: false)
+  final Category category;
+  final UnmodifiableListView<Item> items;
+  Platform platform;
+  Map<String, Platform> altPlatforms;
+
+  int get price => items.fold(0, (total, item) => item.price + total);
+
+  Order(this.category, [Iterable<Item> items])
+      : this.items = new UnmodifiableListView<Item>(
+            new List<Item>.unmodifiable(items ?? const <Item>[]));
+
+  factory Order.fromJson(Map<String, dynamic> json) => _$OrderFromJson(json);
+
+  bool operator ==(Object other) =>
+      other is Order &&
+      count == other.count &&
+      isRushed == other.isRushed &&
+      _deepEquals(items, other.items) &&
+      _deepEquals(altPlatforms, other.altPlatforms);
+}
+
+@JsonSerializable(nullable: false)
+class Item extends Object with _$ItemSerializerMixin {
+  final int price;
+  @JsonKey(includeIfNull: false, name: 'item-number')
+  int itemNumber;
+  List<DateTime> saleDates;
+  List<int> rates;
+
+  Item([this.price]);
+
+  factory Item.fromJson(Map<String, dynamic> json) => _$ItemFromJson(json);
+
+  bool operator ==(Object other) =>
+      other is Item &&
+      price == other.price &&
+      itemNumber == other.itemNumber &&
+      _deepEquals(saleDates, other.saleDates);
+}
+
+bool _deepEquals(a, b) => const DeepCollectionEquality().equals(a, b);
+
+class Platform {
+  final String description;
+
+  static const Platform foo = const Platform._('foo');
+  static const Platform undefined = const Platform._('undefined');
+  const Platform._(this.description);
+
+  factory Platform.fromJson(String value) {
+    switch (value) {
+      case 'foo':
+        return foo;
+      case 'undefined':
+        return undefined;
+      default:
+        throw new ArgumentError.value(value, 'value', 'Not a supported value.');
+    }
+  }
+
+  String toJson() => description;
+}
+
+@JsonSerializable(nullable: false)
+class Numbers extends Object with _$NumbersSerializerMixin {
+  List<int> ints;
+  List<num> nums;
+  List<double> doubles;
+
+  @JsonKey(nullable: false)
+  List<double> nnDoubles;
+
+  Numbers();
+
+  factory Numbers.fromJson(Map<String, dynamic> json) =>
+      _$NumbersFromJson(json);
+
+  bool operator ==(Object other) =>
+      other is Numbers &&
+      _deepEquals(ints, other.ints) &&
+      _deepEquals(nums, other.nums) &&
+      _deepEquals(doubles, other.doubles) &&
+      _deepEquals(nnDoubles, other.nnDoubles);
+}

json_serializable/test/test_files/json_test_example.non_nullable.g.dart

@@ -0,0 +1,105 @@
+// Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of json_serializable.test.json_test_example_non_nullable;
+
+// **************************************************************************
+// Generator: JsonSerializableGenerator
+// **************************************************************************
+
+Person _$PersonFromJson(Map<String, dynamic> json) => new Person(
+    json['firstName'] as String,
+    json['lastName'] as String,
+    House.values.singleWhere((x) => x.toString() == "House.${json[r'$house']}"),
+    middleName: json['middleName'] as String,
+    dateOfBirth: DateTime.parse(json['dateOfBirth'] as String));
+
+abstract class _$PersonSerializerMixin {
+  String get firstName;
+  String get middleName;
+  String get lastName;
+  DateTime get dateOfBirth;
+  House get house;
+  Map<String, dynamic> toJson() => <String, dynamic>{
+        'firstName': firstName,
+        'middleName': middleName,
+        'lastName': lastName,
+        'dateOfBirth': dateOfBirth.toIso8601String(),
+        r'$house': house.toString().split('.')[1]
+      };
+}
+
+Order _$OrderFromJson(Map<String, dynamic> json) => new Order(
+    Category.values
+        .singleWhere((x) => x.toString() == "Category.${json['category']}"),
+    (json['items'] as List)
+        .map((e) => new Item.fromJson(e as Map<String, dynamic>)))
+  ..count = json['count'] as int
+  ..isRushed = json['isRushed'] as bool
+  ..platform = new Platform.fromJson(json['platform'] as String)
+  ..altPlatforms = new Map<String, Platform>.fromIterables(
+      (json['altPlatforms'] as Map<String, dynamic>).keys,
+      (json['altPlatforms'] as Map)
+          .values
+          .map((e) => new Platform.fromJson(e as String)));
+
+abstract class _$OrderSerializerMixin {
+  int get count;
+  bool get isRushed;
+  Category get category;
+  UnmodifiableListView<Item> get items;
+  Platform get platform;
+  Map<String, Platform> get altPlatforms;
+  Map<String, dynamic> toJson() => <String, dynamic>{
+        'count': count,
+        'isRushed': isRushed,
+        'category': category.toString().split('.')[1],
+        'items': items,
+        'platform': platform,
+        'altPlatforms': altPlatforms
+      };
+}
+
+Item _$ItemFromJson(Map<String, dynamic> json) => new Item(json['price'] as int)
+  ..itemNumber = json['item-number'] as int
+  ..saleDates = (json['saleDates'] as List)
+      .map((e) => DateTime.parse(e as String))
+      .toList()
+  ..rates = (json['rates'] as List).map((e) => e as int).toList();
+
+abstract class _$ItemSerializerMixin {
+  int get price;
+  int get itemNumber;
+  List<DateTime> get saleDates;
+  List<int> get rates;
+  Map<String, dynamic> toJson() => <String, dynamic>{
+        'price': price,
+        'item-number': itemNumber,
+        'saleDates': saleDates.map((e) => e.toIso8601String()).toList(),
+        'rates': rates
+      };
+}
+
+Numbers _$NumbersFromJson(Map<String, dynamic> json) => new Numbers()
+  ..ints = (json['ints'] as List).map((e) => e as int).toList()
+  ..nums = (json['nums'] as List).map((e) => e as num).toList()
+  ..doubles =
+      (json['doubles'] as List).map((e) => (e as num).toDouble()).toList()
+  ..nnDoubles =
+      (json['nnDoubles'] as List).map((e) => (e as num).toDouble()).toList();
+
+abstract class _$NumbersSerializerMixin {
+  List<int> get ints;
+  List<num> get nums;
+  List<double> get doubles;
+  List<double> get nnDoubles;
+  Map<String, dynamic> toJson() => <String, dynamic>{
+        'ints': ints,
+        'nums': nums,
+        'doubles': doubles,
+        'nnDoubles': nnDoubles
+      };
+}

json_serializable/test/test_files/kitchen_sink.non_nullable.g.dart

@@ -64,48 +64,36 @@ abstract class _$KitchenSinkSerializerMixin {
   Map<String, bool> get val;
   bool get writeNotNull;
   String get string;
-  Map<String, dynamic> toJson() {
-    var val = <String, dynamic>{};
-
-    void writeNotNull(String key, dynamic value) {
-      if (value != null) {
-        val[key] = value;
-      }
-    }
-
-    writeNotNull('dateTime', dateTime.toIso8601String());
-    writeNotNull('iterable', iterable.toList());
-    val['dynamicIterable'] = dynamicIterable.toList();
-    val['objectIterable'] = objectIterable.toList();
-    val['intIterable'] = intIterable.toList();
-    val['datetime-iterable'] =
-        dateTimeIterable.map((e) => e.toIso8601String()).toList();
-    val['list'] = list;
-    val['dynamicList'] = dynamicList;
-    val['objectList'] = objectList;
-    val['intList'] = intList;
-    writeNotNull(
-        'dateTimeList', dateTimeList.map((e) => e.toIso8601String()).toList());
-    val['map'] = map;
-    val['stringStringMap'] = stringStringMap;
-    val['stringIntMap'] = stringIntMap;
-    val['stringDateTimeMap'] = new Map<String, dynamic>.fromIterables(
-        stringDateTimeMap.keys,
-        stringDateTimeMap.values.map((e) => e.toIso8601String()));
-    writeNotNull(
-        'crazyComplex',
-        crazyComplex
+  Map<String, dynamic> toJson() => <String, dynamic>{
+        'dateTime': dateTime.toIso8601String(),
+        'iterable': iterable.toList(),
+        'dynamicIterable': dynamicIterable.toList(),
+        'objectIterable': objectIterable.toList(),
+        'intIterable': intIterable.toList(),
+        'datetime-iterable':
+            dateTimeIterable.map((e) => e.toIso8601String()).toList(),
+        'list': list,
+        'dynamicList': dynamicList,
+        'objectList': objectList,
+        'intList': intList,
+        'dateTimeList': dateTimeList.map((e) => e.toIso8601String()).toList(),
+        'map': map,
+        'stringStringMap': stringStringMap,
+        'stringIntMap': stringIntMap,
+        'stringDateTimeMap': new Map<String, dynamic>.fromIterables(
+            stringDateTimeMap.keys,
+            stringDateTimeMap.values.map((e) => e.toIso8601String())),
+        'crazyComplex': crazyComplex
             .map((e) => new Map<String, dynamic>.fromIterables(
                 e.keys,
                 e.values.map((e) => new Map<String, dynamic>.fromIterables(
                     e.keys,
                     e.values.map((e) => e
                         .map((e) => e.map((e) => e.toIso8601String()).toList())
                         .toList())))))
-            .toList());
-    writeNotNull('val', this.val);
-    val['writeNotNull'] = this.writeNotNull;
-    val[r'$string'] = string;
-    return val;
-  }
+            .toList(),
+        'val': val,
+        'writeNotNull': writeNotNull,
+        r'$string': string
+      };
 }