Fix encoding nullable values with converters, prepare for release (#1231

)

Fixes #1229

json_serializable/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 6.5.4
+
+- Fixed handling of nullable fields with converters which return non-nullable
+  values.
+
 ## 6.5.3
 
 - Fixed handling of nullable `enum` fields with `includeIfNull: false`.

json_serializable/lib/src/encoder_helper.dart

@@ -178,7 +178,7 @@ abstract class EncodeHelper implements HelperCore {
         hasConverterNullEncode(field.type, helperContext);
 
     if (nullableEncodeConverter != null) {
-      return !nullableEncodeConverter;
+      return !nullableEncodeConverter && !field.type.isNullableType;
     }
 
     // We can consider enums as kinda like having custom converters

json_serializable/pubspec.yaml

@@ -1,5 +1,5 @@
 name: json_serializable
-version: 6.5.3
+version: 6.5.4
 description: >-
   Automatically generate code for converting to and from JSON by annotating
   Dart classes.

json_serializable/test/integration/converter_examples.dart

@@ -95,3 +95,27 @@ class _Issue1202RegressionNotNullConverter extends JsonConverter<int, String> {
   @override
   String toJson(int object) => object.toString();
 }
+
+class DateTimeConverter extends JsonConverter<DateTime, String> {
+  const DateTimeConverter();
+  @override
+  DateTime fromJson(String json) => DateTime.parse(json).toLocal();
+  @override
+  String toJson(DateTime object) => object.toUtc().toIso8601String();
+}
+
+@JsonSerializable()
+@DateTimeConverter()
+class Regression1229 {
+  @JsonKey(includeIfNull: false)
+  final DateTime? date;
+
+  Regression1229({
+    this.date,
+  });
+
+  factory Regression1229.fromJson(Map<String, dynamic> json) =>
+      _$Regression1229FromJson(json);
+
+  Map<String, dynamic> toJson() => _$Regression1229ToJson(this);
+}

json_serializable/test/integration/integration_test.dart

@@ -419,4 +419,9 @@ void main() {
     final instance = Issue1226Regression(durationType: null);
     expect(instance.toJson(), isEmpty);
   });
+
+  test('Regression1229', () {
+    final instance = Regression1229();
+    expect(instance.toJson(), isEmpty);
+  });
 }