migrate example to nullsafety (lejard-h#331)

README.md

@@ -25,7 +25,6 @@ Please refer to the installation guide at [pub.dev](https://pub.dev/packages/cho
 
 * [json serializable Converter](https://github.com/lejard-h/chopper/blob/master/example/bin/main_json_serializable.dart)
 * [built value Converter](https://github.com/lejard-h/chopper/blob/master/example/bin/main_built_value.dart)
-* [Angular](https://github.com/lejard-h/chopper/blob/master/example/web/main.dart)
 
 ## [Issue Tracker](https://github.com/lejard-h/chopper/issues)
 

chopper/README.md

@@ -45,6 +45,5 @@ Latest versions:
 
 * [json_serializable Converter](https://github.com/lejard-h/chopper/blob/master/example/bin/main_json_serializable.dart)
 * [built_value Converter](https://github.com/lejard-h/chopper/blob/master/example/bin/main_built_value.dart)
-* [Angular](https://github.com/lejard-h/chopper/blob/master/example/web/main.dart)
 
 ## If you encounter any issues, or need a feature implemented, please visit [Chopper's Issue Tracker on GitHub](https://github.com/lejard-h/chopper/issues).

example/bin/main_built_value.dart

@@ -1,4 +1,5 @@
 import 'package:built_collection/built_collection.dart';
+import 'package:built_value/serializer.dart';
 import 'package:chopper/chopper.dart';
 import 'package:chopper_example/built_value_resource.dart';
 import 'package:chopper_example/built_value_serializers.dart';
@@ -52,16 +53,22 @@ main() async {
 }
 
 class BuiltValueConverter extends JsonConverter {
-  T _deserialize<T>(dynamic value) => jsonSerializers.deserializeWith<T>(
-        jsonSerializers.serializerForType(T),
-        value,
-      );
+  T? _deserialize<T>(dynamic value) {
+    final serializer = jsonSerializers.serializerForType(T) as Serializer<T>?;
+    if (serializer == null) {
+      throw Exception('No serializer for type ${T}');
+    }
+    return jsonSerializers.deserializeWith<T>(
+      serializer,
+      value,
+    );
+  }
 
   BuiltList<T> _deserializeListOf<T>(Iterable value) => BuiltList(
         value.map((value) => _deserialize<T>(value)).toList(growable: false),
       );
 
-  dynamic _decode<T>(entity) {
+  dynamic _decode<T>(dynamic entity) {
     /// handle case when we want to access to Map<String, dynamic> directly
     /// getResource or getMapResource
     /// Avoid dynamic or unconverted value, this could lead to several issues

example/bin/main_json_serializable.dart

@@ -67,7 +67,7 @@ class JsonSerializableConverter extends JsonConverter {
 
   JsonSerializableConverter(this.factories);
 
-  T _decodeMap<T>(Map<String, dynamic> values) {
+  T? _decodeMap<T>(Map<String, dynamic> values) {
     /// Get jsonFactory using Type parameters
     /// if not found or invalid, throw error or return null
     final jsonFactory = factories[T];
@@ -79,13 +79,13 @@ class JsonSerializableConverter extends JsonConverter {
     return jsonFactory(values);
   }
 
-  List<T> _decodeList<T>(List values) =>
+  List<T> _decodeList<T>(Iterable values) =>
       values.where((v) => v != null).map<T>((v) => _decode<T>(v)).toList();
 
-  dynamic _decode<T>(entity) {
+  dynamic _decode<T>(dynamic entity) {
     if (entity is Iterable) return _decodeList<T>(entity);
 
-    if (entity is Map) return _decodeMap<T>(entity);
+    if (entity is Map<String, dynamic>) return _decodeMap<T>(entity);
 
     return entity;
   }

example/lib/built_value_resource.dart

@@ -33,7 +33,7 @@ abstract class ResourceError
 
 @ChopperApi(baseUrl: "/resources")
 abstract class MyService extends ChopperService {
-  static MyService create([ChopperClient client]) => _$MyService(client);
+  static MyService create([ChopperClient? client]) => _$MyService(client);
 
   @Get(path: "/{id}/")
   Future<Response> getResource(@Path() String id);
@@ -46,5 +46,5 @@ abstract class MyService extends ChopperService {
 
   @Post()
   Future<Response<Resource>> newResource(@Body() Resource resource,
-      {@Header() String name});
+      {@Header() String? name});
 }