#101 Union contributor is generating fromJson as method and not factory

- Also swapped "expected" and "actual" values in tests

example/lib/unions/from_json.dart

@@ -5,34 +5,46 @@ import 'package:data_class_plugin/data_class_plugin.dart';
   fromJson: true,
   toJson: false,
 )
-abstract class Response {
+class Response {
   const Response._();
 
+  /// Creates an instance of [Response] from [json]
+  factory Response.fromJson(Map<dynamic, dynamic> json) {
+    switch (json['status']) {
+      case 'ok':
+        return ResponseOk.fromJson(json);
+      case 'unauthorized':
+        return ResponseUnauthorized.fromJson(json);
+      default:
+        return ResponseError.fromJson(json);
+    }
+  }
+
   const factory Response.ok({
     required int data,
-  }) = Ok;
+  }) = ResponseOk;
 
-  const factory Response.unauthorized() = Unauthorized;
+  const factory Response.unauthorized() = ResponseUnauthorized;
 
   const factory Response.error({
     required Object type,
     @JsonKey(ignore: true) StackTrace? stackTrace,
-  }) = Error;
+  }) = ResponseError;
 
   /// Executes one of the provided callbacks based on a type match
   R when<R>({
-    required R Function(Ok value) ok,
-    required R Function(Unauthorized value) unauthorized,
-    required R Function(Error value) error,
+    required R Function(ResponseOk value) ok,
+    required R Function(ResponseUnauthorized value) unauthorized,
+    required R Function(ResponseError value) error,
   }) {
-    if (this is Ok) {
-      return ok(this as Ok);
+    if (this is ResponseOk) {
+      return ok(this as ResponseOk);
     }
-    if (this is Unauthorized) {
-      return unauthorized(this as Unauthorized);
+    if (this is ResponseUnauthorized) {
+      return unauthorized(this as ResponseUnauthorized);
     }
-    if (this is Error) {
-      return error(this as Error);
+    if (this is ResponseError) {
+      return error(this as ResponseError);
     }
     throw UnimplementedError('Unknown instance of $this used in when(..)');
   }
@@ -41,66 +53,60 @@ abstract class Response {
   ///
   /// If no match is found [orElse] is executed
   R maybeWhen<R>({
-    R Function(Ok value)? ok,
-    R Function(Unauthorized value)? unauthorized,
-    R Function(Error value)? error,
+    R Function(ResponseOk value)? ok,
+    R Function(ResponseUnauthorized value)? unauthorized,
+    R Function(ResponseError value)? error,
     required R Function() orElse,
   }) {
-    if (this is Ok) {
-      return ok?.call(this as Ok) ?? orElse();
+    if (this is ResponseOk) {
+      return ok?.call(this as ResponseOk) ?? orElse();
     }
-    if (this is Unauthorized) {
-      return unauthorized?.call(this as Unauthorized) ?? orElse();
+    if (this is ResponseUnauthorized) {
+      return unauthorized?.call(this as ResponseUnauthorized) ?? orElse();
     }
-    if (this is Error) {
-      return error?.call(this as Error) ?? orElse();
+    if (this is ResponseError) {
+      return error?.call(this as ResponseError) ?? orElse();
     }
     throw UnimplementedError('Unknown instance of $this used in maybeWhen(..)');
   }
-
-  /// Creates an instance of [Response] from [json]
-  Response fromJson(Map<dynamic, dynamic> json) {
-// TODO: Implement
-    throw UnimplementedError();
-  }
 }
 
-class Ok extends Response {
-  const Ok({
+class ResponseOk extends Response {
+  const ResponseOk({
     required this.data,
   }) : super._();
 
   final int data;
 
-  /// Creates an instance of [Ok] from [json]
-  factory Ok.fromJson(Map<dynamic, dynamic> json) {
-    return Ok(
+  /// Creates an instance of [ResponseOk] from [json]
+  factory ResponseOk.fromJson(Map<dynamic, dynamic> json) {
+    return ResponseOk(
       data: json['data'] as int,
     );
   }
 }
 
-class Unauthorized extends Response {
-  const Unauthorized() : super._();
+class ResponseUnauthorized extends Response {
+  const ResponseUnauthorized() : super._();
 
-  /// Creates an instance of [Unauthorized] from [json]
-  factory Unauthorized.fromJson(Map<dynamic, dynamic> json) {
-    return Unauthorized();
+  /// Creates an instance of [ResponseUnauthorized] from [json]
+  factory ResponseUnauthorized.fromJson(Map<dynamic, dynamic> json) {
+    return ResponseUnauthorized();
   }
 }
 
-class Error extends Response {
-  const Error({
+class ResponseError extends Response {
+  const ResponseError({
     required this.type,
     this.stackTrace,
   }) : super._();
 
   final Object type;
   final StackTrace? stackTrace;
 
-  /// Creates an instance of [Error] from [json]
-  factory Error.fromJson(Map<dynamic, dynamic> json) {
-    return Error(
+  /// Creates an instance of [ResponseError] from [json]
+  factory ResponseError.fromJson(Map<dynamic, dynamic> json) {
+    return ResponseError(
       type: jsonConverterRegistrant.find(Object).fromJson(json['type']) as Object,
     );
   }

lib/src/contributors/class/shorthand_constructor.dart

@@ -40,7 +40,8 @@ class ShorthandConstructorAssistContributor extends Object
     if (classNode == null ||
         classNode.members.isEmpty ||
         classNode.declaredElement == null ||
-        classNode.declaredElement!.hasDataClassAnnotation) {
+        classNode.declaredElement!.hasDataClassAnnotation ||
+        classNode.declaredElement!.hasUnionAnnotation) {
       return;
     }
 

lib/src/contributors/class/union_assist_contributor.dart

@@ -85,6 +85,12 @@ class UnionAssistContributor extends Object
           fileEditBuilder: fileEditBuilder,
         );
 
+        _generateGenerativeConstructor(
+          classNode: classNode,
+          classElement: classElement,
+          fileEditBuilder: fileEditBuilder,
+        );
+
         if (unionInternalAnnotation.fromJson) {
           _generateFromJsonFunction(
             classNode: classNode,
@@ -109,12 +115,6 @@ class UnionAssistContributor extends Object
           unionInternalAnnotation: unionInternalAnnotation,
         );
 
-        _generateGenerativeConstructor(
-          classNode: classNode,
-          classElement: classElement,
-          fileEditBuilder: fileEditBuilder,
-        );
-
         fileEditBuilder.format(SourceRange(classNode.offset, classNode.length));
       },
     );
@@ -189,7 +189,7 @@ class UnionAssistContributor extends Object
     required final UnionInternal unionInternalAnnotation,
   }) {
     for (final ConstructorElement ctor in classElement.constructors.reversed) {
-      if (!ctor.isFactory || ctor.name.isEmpty) {
+      if (!ctor.isFactory || ctor.name.isEmpty || ctor.name == 'fromJson') {
         continue;
       }
 
@@ -264,11 +264,11 @@ class UnionAssistContributor extends Object
     required final ClassElement classElement,
     required final DartFileEditBuilder fileEditBuilder,
   }) {
-    final SourceRange? sourceRange = classNode.members.getSourceRangeForMethod('fromJson');
+    final SourceRange? sourceRange = classNode.members.getSourceRangeForConstructor('fromJson');
 
     if (sourceRange == null) {
       fileEditBuilder.addInsertion(
-        classNode.rightBracket.offset,
+        1 + classNode.leftBracket.offset,
         (DartEditBuilder builder) =>
             _writeFromJsonFunction(classElement: classElement, builder: builder),
       );
@@ -598,8 +598,7 @@ class UnionAssistContributor extends Object
   }) {
     builder
       ..writeln('/// Creates an instance of [${classElement.name}] from [json]')
-      ..writeln('${classElement.thisType} fromJson(Map<dynamic, dynamic> json) {')
-      ..writeln('// TODO: Implement')
+      ..writeln('factory ${classElement.name}.fromJson(Map<dynamic, dynamic> json) {')
       ..writeln('throw UnimplementedError();')
       ..writeln('}');
   }

test/contributors/annotations/union/test_files/in_data_class.dart

@@ -6,8 +6,6 @@ import 'package:data_class_plugin/data_class_plugin.dart';
   toJson: false,
 )
 class AsyncResult<T> {
-  const AsyncResult._();
-
   const factory AsyncResult.data({
     required T data,
   }) = AsyncResultData<T>;

test/contributors/annotations/union/test_files/in_from_json.dart

@@ -5,17 +5,15 @@ import 'package:data_class_plugin/data_class_plugin.dart';
   fromJson: true,
   toJson: false,
 )
-class AsyncResult<T> {
-  const AsyncResult._();
+class Response {
+  const factory Response.ok({
+    required int data,
+  }) = ResponseOk;
 
-  const factory AsyncResult.data({
-    required T data,
-  }) = AsyncResultData<T>;
+  const factory Response.unauthorized() = ResponseUnauthorized;
 
-  const factory AsyncResult.loading() = AsyncResultLoading<T>;
-
-  const factory AsyncResult.error({
-    required Object error,
-    StackTrace? stackTrace,
-  }) = AsyncResultError<T>;
+  const factory Response.error({
+    required Object type,
+    @JsonKey(ignore: true) StackTrace? stackTrace,
+  }) = ResponseError;
 }

test/contributors/annotations/union/test_files/in_shared_fields.dart

@@ -6,8 +6,6 @@ import 'package:data_class_plugin/data_class_plugin.dart';
   toJson: false,
 )
 abstract class User {
-  const User._();
-
   const factory User.normal({
     required String id,
     required String username,

test/contributors/annotations/union/test_files/in_to_json.dart

@@ -6,8 +6,6 @@ import 'package:data_class_plugin/data_class_plugin.dart';
   toJson: true,
 )
 class AsyncResult<T> {
-  const AsyncResult._();
-
   const factory AsyncResult.data({
     required T data,
   }) = AsyncResultData<T>;

test/contributors/annotations/union/test_files/in_union_field_value.dart

@@ -17,8 +17,6 @@ class User {
   toJson: false,
 )
 class UnionWithDefaultValues {
-  const UnionWithDefaultValues._();
-
   const factory UnionWithDefaultValues.impl({
     @UnionFieldValue<User>(User.none) User value,
     @UnionFieldValue<String>('') String value2,