[dart][dart-dio] Correctly type responses and futures (#8195)

* don't rely on implicit dynamics
* this is a requirement for NNBD
* add space between return type and some method names

modules/openapi-generator/src/main/resources/dart-dio/api.mustache

@@ -19,7 +19,7 @@ class {{classname}} {
     /// {{{summary}}}
     ///
     /// {{{notes}}}
-    Future<Response{{#returnType}}<{{{returnType}}}>{{/returnType}}>{{nickname}}({{^hasRequiredParams}}{ {{/hasRequiredParams}}{{#requiredParams}}
+    Future<Response<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}}>> {{nickname}}({{^hasRequiredParams}}{ {{/hasRequiredParams}}{{#requiredParams}}
         {{{dataType}}} {{paramName}},{{#-last}} { {{/-last}}{{/requiredParams}}{{#optionalParams}}
         {{{dataType}}} {{paramName}},{{/optionalParams}}
         CancelToken cancelToken,

modules/openapi-generator/src/main/resources/dart2/api.mustache

@@ -49,7 +49,7 @@ class {{{classname}}} {
   ///
     {{/-last}}
   {{/allParams}}
-  {{#returnType}}Future<Response> {{/returnType}}{{^returnType}}Future {{/returnType}}{{{nickname}}}WithHttpInfo({{#allParams}}{{#required}}{{{dataType}}} {{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}}{{#hasOptionalParams}}{ {{#allParams}}{{^required}}{{{dataType}}} {{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}} }{{/hasOptionalParams}}) async {
+  Future<Response> {{{nickname}}}WithHttpInfo({{#allParams}}{{#required}}{{{dataType}}} {{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}}{{#hasOptionalParams}}{ {{#allParams}}{{^required}}{{{dataType}}} {{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}} }{{/hasOptionalParams}}) async {
   {{#hasParams}}
     // Verify required params are set.
     {{#allParams}}
@@ -175,7 +175,7 @@ class {{{classname}}} {
   ///
     {{/-last}}
   {{/allParams}}
-  {{#returnType}}Future<{{{returnType}}}> {{/returnType}}{{^returnType}}Future {{/returnType}}{{{nickname}}}({{#allParams}}{{#required}}{{{dataType}}} {{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}}{{#hasOptionalParams}}{ {{#allParams}}{{^required}}{{{dataType}}} {{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}} }{{/hasOptionalParams}}) async {
+  Future<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}}> {{{nickname}}}({{#allParams}}{{#required}}{{{dataType}}} {{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}}{{#hasOptionalParams}}{ {{#allParams}}{{^required}}{{{dataType}}} {{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}} }{{/hasOptionalParams}}) async {
     final response = await {{{nickname}}}WithHttpInfo({{#allParams}}{{#required}}{{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}}{{#hasOptionalParams}} {{#allParams}}{{^required}}{{{paramName}}}: {{{paramName}}}{{^-last}}, {{/-last}}{{/required}}{{/allParams}} {{/hasOptionalParams}});
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/client/petstore/dart-dio/petstore_client_lib/lib/api/pet_api.dart

@@ -18,7 +18,7 @@ class PetApi {
     /// Add a new pet to the store
     ///
     /// 
-    Future<Response>addPet(
+    Future<Response<void>> addPet(
         Pet body, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -69,7 +69,7 @@ class PetApi {
     /// Deletes a pet
     ///
     /// 
-    Future<Response>deletePet(
+    Future<Response<void>> deletePet(
         int petId, { 
         String apiKey,
         CancelToken cancelToken,
@@ -115,7 +115,7 @@ class PetApi {
     /// Finds Pets by status
     ///
     /// Multiple status values can be provided with comma separated strings
-    Future<Response<BuiltList<Pet>>>findPetsByStatus(
+    Future<Response<BuiltList<Pet>>> findPetsByStatus(
         BuiltList<String> status, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -174,7 +174,7 @@ class PetApi {
     /// Finds Pets by tags
     ///
     /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
-    Future<Response<BuiltList<Pet>>>findPetsByTags(
+    Future<Response<BuiltList<Pet>>> findPetsByTags(
         BuiltList<String> tags, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -233,7 +233,7 @@ class PetApi {
     /// Find pet by ID
     ///
     /// Returns a single pet
-    Future<Response<Pet>>getPetById(
+    Future<Response<Pet>> getPetById(
         int petId, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -292,7 +292,7 @@ class PetApi {
     /// Update an existing pet
     ///
     /// 
-    Future<Response>updatePet(
+    Future<Response<void>> updatePet(
         Pet body, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -343,7 +343,7 @@ class PetApi {
     /// Updates a pet in the store with form data
     ///
     /// 
-    Future<Response>updatePetWithForm(
+    Future<Response<void>> updatePetWithForm(
         int petId, { 
         String name,
         String status,
@@ -396,7 +396,7 @@ class PetApi {
     /// uploads an image
     ///
     /// 
-    Future<Response<ApiResponse>>uploadFile(
+    Future<Response<ApiResponse>> uploadFile(
         int petId, { 
         String additionalMetadata,
         Uint8List file,

samples/client/petstore/dart-dio/petstore_client_lib/lib/api/store_api.dart

@@ -15,7 +15,7 @@ class StoreApi {
     /// Delete purchase order by ID
     ///
     /// For valid response try integer IDs with value < 1000. Anything above 1000 or nonintegers will generate API errors
-    Future<Response>deleteOrder(
+    Future<Response<void>> deleteOrder(
         String orderId, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -54,7 +54,7 @@ class StoreApi {
     /// Returns pet inventories by status
     ///
     /// Returns a map of status codes to quantities
-    Future<Response<BuiltMap<String, int>>>getInventory({ 
+    Future<Response<BuiltMap<String, int>>> getInventory({ 
         CancelToken cancelToken,
         Map<String, String> headers,
         ProgressCallback onSendProgress,
@@ -113,7 +113,7 @@ class StoreApi {
     /// Find purchase order by ID
     ///
     /// For valid response try integer IDs with value <= 5 or > 10. Other values will generated exceptions
-    Future<Response<Order>>getOrderById(
+    Future<Response<Order>> getOrderById(
         int orderId, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -165,7 +165,7 @@ class StoreApi {
     /// Place an order for a pet
     ///
     /// 
-    Future<Response<Order>>placeOrder(
+    Future<Response<Order>> placeOrder(
         Order body, { 
         CancelToken cancelToken,
         Map<String, String> headers,

samples/client/petstore/dart-dio/petstore_client_lib/lib/api/user_api.dart

@@ -15,7 +15,7 @@ class UserApi {
     /// Create user
     ///
     /// This can only be done by the logged in user.
-    Future<Response>createUser(
+    Future<Response<void>> createUser(
         User body, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -58,7 +58,7 @@ class UserApi {
     /// Creates list of users with given input array
     ///
     /// 
-    Future<Response>createUsersWithArrayInput(
+    Future<Response<void>> createUsersWithArrayInput(
         BuiltList<User> body, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -102,7 +102,7 @@ class UserApi {
     /// Creates list of users with given input array
     ///
     /// 
-    Future<Response>createUsersWithListInput(
+    Future<Response<void>> createUsersWithListInput(
         BuiltList<User> body, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -146,7 +146,7 @@ class UserApi {
     /// Delete user
     ///
     /// This can only be done by the logged in user.
-    Future<Response>deleteUser(
+    Future<Response<void>> deleteUser(
         String username, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -185,7 +185,7 @@ class UserApi {
     /// Get user by user name
     ///
     /// 
-    Future<Response<User>>getUserByName(
+    Future<Response<User>> getUserByName(
         String username, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -237,7 +237,7 @@ class UserApi {
     /// Logs user into the system
     ///
     /// 
-    Future<Response<String>>loginUser(
+    Future<Response<String>> loginUser(
         String username,
         String password, { 
         CancelToken cancelToken,
@@ -291,7 +291,7 @@ class UserApi {
     /// Logs out current logged in user session
     ///
     /// 
-    Future<Response>logoutUser({ 
+    Future<Response<void>> logoutUser({ 
         CancelToken cancelToken,
         Map<String, String> headers,
         ProgressCallback onSendProgress,
@@ -329,7 +329,7 @@ class UserApi {
     /// Updated user
     ///
     /// This can only be done by the logged in user.
-    Future<Response>updateUser(
+    Future<Response<void>> updateUser(
         String username,
         User body, { 
         CancelToken cancelToken,

samples/client/petstore/dart2/petstore_client_lib/lib/api/pet_api.dart

@@ -23,7 +23,7 @@ class PetApi {
   ///
   /// * [Pet] body (required):
   ///   Pet object that needs to be added to the store
-  Future addPetWithHttpInfo(Pet body) async {
+  Future<Response> addPetWithHttpInfo(Pet body) async {
     // Verify required params are set.
     if (body == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: body');
@@ -71,7 +71,7 @@ class PetApi {
   ///
   /// * [Pet] body (required):
   ///   Pet object that needs to be added to the store
-  Future addPet(Pet body) async {
+  Future<void> addPet(Pet body) async {
     final response = await addPetWithHttpInfo(body);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -88,7 +88,7 @@ class PetApi {
   ///   Pet id to delete
   ///
   /// * [String] apiKey:
-  Future deletePetWithHttpInfo(int petId, { String apiKey }) async {
+  Future<Response> deletePetWithHttpInfo(int petId, { String apiKey }) async {
     // Verify required params are set.
     if (petId == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: petId');
@@ -143,7 +143,7 @@ class PetApi {
   ///   Pet id to delete
   ///
   /// * [String] apiKey:
-  Future deletePet(int petId, { String apiKey }) async {
+  Future<void> deletePet(int petId, { String apiKey }) async {
     final response = await deletePetWithHttpInfo(petId,  apiKey: apiKey );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -389,7 +389,7 @@ class PetApi {
   ///
   /// * [Pet] body (required):
   ///   Pet object that needs to be added to the store
-  Future updatePetWithHttpInfo(Pet body) async {
+  Future<Response> updatePetWithHttpInfo(Pet body) async {
     // Verify required params are set.
     if (body == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: body');
@@ -437,7 +437,7 @@ class PetApi {
   ///
   /// * [Pet] body (required):
   ///   Pet object that needs to be added to the store
-  Future updatePet(Pet body) async {
+  Future<void> updatePet(Pet body) async {
     final response = await updatePetWithHttpInfo(body);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -458,7 +458,7 @@ class PetApi {
   ///
   /// * [String] status:
   ///   Updated status of the pet
-  Future updatePetWithFormWithHttpInfo(int petId, { String name, String status }) async {
+  Future<Response> updatePetWithFormWithHttpInfo(int petId, { String name, String status }) async {
     // Verify required params are set.
     if (petId == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: petId');
@@ -527,7 +527,7 @@ class PetApi {
   ///
   /// * [String] status:
   ///   Updated status of the pet
-  Future updatePetWithForm(int petId, { String name, String status }) async {
+  Future<void> updatePetWithForm(int petId, { String name, String status }) async {
     final response = await updatePetWithFormWithHttpInfo(petId,  name: name, status: status );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/client/petstore/dart2/petstore_client_lib/lib/api/store_api.dart

@@ -25,7 +25,7 @@ class StoreApi {
   ///
   /// * [String] orderId (required):
   ///   ID of the order that needs to be deleted
-  Future deleteOrderWithHttpInfo(String orderId) async {
+  Future<Response> deleteOrderWithHttpInfo(String orderId) async {
     // Verify required params are set.
     if (orderId == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: orderId');
@@ -76,7 +76,7 @@ class StoreApi {
   ///
   /// * [String] orderId (required):
   ///   ID of the order that needs to be deleted
-  Future deleteOrder(String orderId) async {
+  Future<void> deleteOrder(String orderId) async {
     final response = await deleteOrderWithHttpInfo(orderId);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/client/petstore/dart2/petstore_client_lib/lib/api/user_api.dart

@@ -25,7 +25,7 @@ class UserApi {
   ///
   /// * [User] body (required):
   ///   Created user object
-  Future createUserWithHttpInfo(User body) async {
+  Future<Response> createUserWithHttpInfo(User body) async {
     // Verify required params are set.
     if (body == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: body');
@@ -75,7 +75,7 @@ class UserApi {
   ///
   /// * [User] body (required):
   ///   Created user object
-  Future createUser(User body) async {
+  Future<void> createUser(User body) async {
     final response = await createUserWithHttpInfo(body);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -90,7 +90,7 @@ class UserApi {
   ///
   /// * [List<User>] body (required):
   ///   List of user object
-  Future createUsersWithArrayInputWithHttpInfo(List<User> body) async {
+  Future<Response> createUsersWithArrayInputWithHttpInfo(List<User> body) async {
     // Verify required params are set.
     if (body == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: body');
@@ -138,7 +138,7 @@ class UserApi {
   ///
   /// * [List<User>] body (required):
   ///   List of user object
-  Future createUsersWithArrayInput(List<User> body) async {
+  Future<void> createUsersWithArrayInput(List<User> body) async {
     final response = await createUsersWithArrayInputWithHttpInfo(body);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -153,7 +153,7 @@ class UserApi {
   ///
   /// * [List<User>] body (required):
   ///   List of user object
-  Future createUsersWithListInputWithHttpInfo(List<User> body) async {
+  Future<Response> createUsersWithListInputWithHttpInfo(List<User> body) async {
     // Verify required params are set.
     if (body == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: body');
@@ -201,7 +201,7 @@ class UserApi {
   ///
   /// * [List<User>] body (required):
   ///   List of user object
-  Future createUsersWithListInput(List<User> body) async {
+  Future<void> createUsersWithListInput(List<User> body) async {
     final response = await createUsersWithListInputWithHttpInfo(body);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -218,7 +218,7 @@ class UserApi {
   ///
   /// * [String] username (required):
   ///   The name that needs to be deleted
-  Future deleteUserWithHttpInfo(String username) async {
+  Future<Response> deleteUserWithHttpInfo(String username) async {
     // Verify required params are set.
     if (username == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: username');
@@ -269,7 +269,7 @@ class UserApi {
   ///
   /// * [String] username (required):
   ///   The name that needs to be deleted
-  Future deleteUser(String username) async {
+  Future<void> deleteUser(String username) async {
     final response = await deleteUserWithHttpInfo(username);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -432,7 +432,7 @@ class UserApi {
   /// Logs out current logged in user session
   ///
   /// Note: This method returns the HTTP [Response].
-  Future logoutUserWithHttpInfo() async {
+  Future<Response> logoutUserWithHttpInfo() async {
     final path = '/user/logout'.replaceAll('{format}', 'json');
 
     Object postBody;
@@ -470,7 +470,7 @@ class UserApi {
   }
 
   /// Logs out current logged in user session
-  Future logoutUser() async {
+  Future<void> logoutUser() async {
     final response = await logoutUserWithHttpInfo();
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -490,7 +490,7 @@ class UserApi {
   ///
   /// * [User] body (required):
   ///   Updated user object
-  Future updateUserWithHttpInfo(String username, User body) async {
+  Future<Response> updateUserWithHttpInfo(String username, User body) async {
     // Verify required params are set.
     if (username == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: username');
@@ -547,7 +547,7 @@ class UserApi {
   ///
   /// * [User] body (required):
   ///   Updated user object
-  Future updateUser(String username, User body) async {
+  Future<void> updateUser(String username, User body) async {
     final response = await updateUserWithHttpInfo(username, body);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/openapi3/client/petstore/dart-dio/petstore_client_lib/lib/api/pet_api.dart

@@ -18,7 +18,7 @@ class PetApi {
     /// Add a new pet to the store
     ///
     /// 
-    Future<Response<Pet>>addPet(
+    Future<Response<Pet>> addPet(
         Pet pet, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -82,7 +82,7 @@ class PetApi {
     /// Deletes a pet
     ///
     /// 
-    Future<Response>deletePet(
+    Future<Response<void>> deletePet(
         int petId, { 
         String apiKey,
         CancelToken cancelToken,
@@ -128,7 +128,7 @@ class PetApi {
     /// Finds Pets by status
     ///
     /// Multiple status values can be provided with comma separated strings
-    Future<Response<BuiltList<Pet>>>findPetsByStatus(
+    Future<Response<BuiltList<Pet>>> findPetsByStatus(
         BuiltList<String> status, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -187,7 +187,7 @@ class PetApi {
     /// Finds Pets by tags
     ///
     /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
-    Future<Response<BuiltList<Pet>>>findPetsByTags(
+    Future<Response<BuiltList<Pet>>> findPetsByTags(
         BuiltList<String> tags, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -246,7 +246,7 @@ class PetApi {
     /// Find pet by ID
     ///
     /// Returns a single pet
-    Future<Response<Pet>>getPetById(
+    Future<Response<Pet>> getPetById(
         int petId, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -305,7 +305,7 @@ class PetApi {
     /// Update an existing pet
     ///
     /// 
-    Future<Response<Pet>>updatePet(
+    Future<Response<Pet>> updatePet(
         Pet pet, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -369,7 +369,7 @@ class PetApi {
     /// Updates a pet in the store with form data
     ///
     /// 
-    Future<Response>updatePetWithForm(
+    Future<Response<void>> updatePetWithForm(
         int petId, { 
         String name,
         String status,
@@ -422,7 +422,7 @@ class PetApi {
     /// uploads an image
     ///
     /// 
-    Future<Response<ApiResponse>>uploadFile(
+    Future<Response<ApiResponse>> uploadFile(
         int petId, { 
         String additionalMetadata,
         Uint8List file,

samples/openapi3/client/petstore/dart-dio/petstore_client_lib/lib/api/store_api.dart

@@ -15,7 +15,7 @@ class StoreApi {
     /// Delete purchase order by ID
     ///
     /// For valid response try integer IDs with value < 1000. Anything above 1000 or nonintegers will generate API errors
-    Future<Response>deleteOrder(
+    Future<Response<void>> deleteOrder(
         String orderId, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -54,7 +54,7 @@ class StoreApi {
     /// Returns pet inventories by status
     ///
     /// Returns a map of status codes to quantities
-    Future<Response<BuiltMap<String, int>>>getInventory({ 
+    Future<Response<BuiltMap<String, int>>> getInventory({ 
         CancelToken cancelToken,
         Map<String, String> headers,
         ProgressCallback onSendProgress,
@@ -113,7 +113,7 @@ class StoreApi {
     /// Find purchase order by ID
     ///
     /// For valid response try integer IDs with value <= 5 or > 10. Other values will generated exceptions
-    Future<Response<Order>>getOrderById(
+    Future<Response<Order>> getOrderById(
         int orderId, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -165,7 +165,7 @@ class StoreApi {
     /// Place an order for a pet
     ///
     /// 
-    Future<Response<Order>>placeOrder(
+    Future<Response<Order>> placeOrder(
         Order order, { 
         CancelToken cancelToken,
         Map<String, String> headers,

samples/openapi3/client/petstore/dart-dio/petstore_client_lib/lib/api/user_api.dart

@@ -15,7 +15,7 @@ class UserApi {
     /// Create user
     ///
     /// This can only be done by the logged in user.
-    Future<Response>createUser(
+    Future<Response<void>> createUser(
         User user, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -67,7 +67,7 @@ class UserApi {
     /// Creates list of users with given input array
     ///
     /// 
-    Future<Response>createUsersWithArrayInput(
+    Future<Response<void>> createUsersWithArrayInput(
         BuiltList<User> user, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -120,7 +120,7 @@ class UserApi {
     /// Creates list of users with given input array
     ///
     /// 
-    Future<Response>createUsersWithListInput(
+    Future<Response<void>> createUsersWithListInput(
         BuiltList<User> user, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -173,7 +173,7 @@ class UserApi {
     /// Delete user
     ///
     /// This can only be done by the logged in user.
-    Future<Response>deleteUser(
+    Future<Response<void>> deleteUser(
         String username, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -219,7 +219,7 @@ class UserApi {
     /// Get user by user name
     ///
     /// 
-    Future<Response<User>>getUserByName(
+    Future<Response<User>> getUserByName(
         String username, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -271,7 +271,7 @@ class UserApi {
     /// Logs user into the system
     ///
     /// 
-    Future<Response<String>>loginUser(
+    Future<Response<String>> loginUser(
         String username,
         String password, { 
         CancelToken cancelToken,
@@ -325,7 +325,7 @@ class UserApi {
     /// Logs out current logged in user session
     ///
     /// 
-    Future<Response>logoutUser({ 
+    Future<Response<void>> logoutUser({ 
         CancelToken cancelToken,
         Map<String, String> headers,
         ProgressCallback onSendProgress,
@@ -370,7 +370,7 @@ class UserApi {
     /// Updated user
     ///
     /// This can only be done by the logged in user.
-    Future<Response>updateUser(
+    Future<Response<void>> updateUser(
         String username,
         User user, { 
         CancelToken cancelToken,

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/api/another_fake_api.dart

@@ -14,7 +14,7 @@ class AnotherFakeApi {
     /// To test special tags
     ///
     /// To test special tags and operation ID starting with number
-    Future<Response<Client>>call123testSpecialTags(
+    Future<Response<Client>> call123testSpecialTags(
         Client client, { 
         CancelToken cancelToken,
         Map<String, String> headers,

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/api/default_api.dart

@@ -14,7 +14,7 @@ class DefaultApi {
     /// 
     ///
     /// 
-    Future<Response<InlineResponseDefault>>fooGet({ 
+    Future<Response<InlineResponseDefault>> fooGet({ 
         CancelToken cancelToken,
         Map<String, String> headers,
         ProgressCallback onSendProgress,

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/api/fake_api.dart

@@ -22,7 +22,7 @@ class FakeApi {
     /// Health check endpoint
     ///
     /// 
-    Future<Response<HealthCheckResult>>fakeHealthGet({ 
+    Future<Response<HealthCheckResult>> fakeHealthGet({ 
         CancelToken cancelToken,
         Map<String, String> headers,
         ProgressCallback onSendProgress,
@@ -73,7 +73,7 @@ class FakeApi {
     /// test http signature authentication
     ///
     /// 
-    Future<Response>fakeHttpSignatureTest(
+    Future<Response<void>> fakeHttpSignatureTest(
         Pet pet, { 
         String query1,
         String header1,
@@ -128,7 +128,7 @@ class FakeApi {
     /// 
     ///
     /// Test serialization of outer boolean types
-    Future<Response<bool>>fakeOuterBooleanSerialize({ 
+    Future<Response<bool>> fakeOuterBooleanSerialize({ 
         bool body,
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -185,7 +185,7 @@ class FakeApi {
     /// 
     ///
     /// Test serialization of object with outer number type
-    Future<Response<OuterComposite>>fakeOuterCompositeSerialize({ 
+    Future<Response<OuterComposite>> fakeOuterCompositeSerialize({ 
         OuterComposite outerComposite,
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -243,7 +243,7 @@ class FakeApi {
     /// 
     ///
     /// Test serialization of outer number types
-    Future<Response<num>>fakeOuterNumberSerialize({ 
+    Future<Response<num>> fakeOuterNumberSerialize({ 
         num body,
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -300,7 +300,7 @@ class FakeApi {
     /// 
     ///
     /// Test serialization of outer string types
-    Future<Response<String>>fakeOuterStringSerialize({ 
+    Future<Response<String>> fakeOuterStringSerialize({ 
         String body,
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -357,7 +357,7 @@ class FakeApi {
     /// 
     ///
     /// For this test, the body for this request much reference a schema named `File`.
-    Future<Response>testBodyWithFileSchema(
+    Future<Response<void>> testBodyWithFileSchema(
         FileSchemaTestClass fileSchemaTestClass, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -402,7 +402,7 @@ class FakeApi {
     /// 
     ///
     /// 
-    Future<Response>testBodyWithQueryParams(
+    Future<Response<void>> testBodyWithQueryParams(
         String query,
         User user, { 
         CancelToken cancelToken,
@@ -449,7 +449,7 @@ class FakeApi {
     /// To test \"client\" model
     ///
     /// To test \"client\" model
-    Future<Response<Client>>testClientModel(
+    Future<Response<Client>> testClientModel(
         Client client, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -507,7 +507,7 @@ class FakeApi {
     /// Fake endpoint for testing various parameters 假端點 偽のエンドポイント 가짜 엔드 포인트 
     ///
     /// Fake endpoint for testing various parameters 假端點 偽のエンドポイント 가짜 엔드 포인트 
-    Future<Response>testEndpointParameters(
+    Future<Response<void>> testEndpointParameters(
         num number,
         double double_,
         String patternWithoutDelimiter,
@@ -583,7 +583,7 @@ class FakeApi {
     /// To test enum parameters
     ///
     /// To test enum parameters
-    Future<Response>testEnumParameters({ 
+    Future<Response<void>> testEnumParameters({ 
         BuiltList<String> enumHeaderStringArray,
         String enumHeaderString,
         BuiltList<String> enumQueryStringArray,
@@ -642,7 +642,7 @@ class FakeApi {
     /// Fake endpoint to test group parameters (optional)
     ///
     /// Fake endpoint to test group parameters (optional)
-    Future<Response>testGroupParameters(
+    Future<Response<void>> testGroupParameters(
         int requiredStringGroup,
         bool requiredBooleanGroup,
         int requiredInt64Group, { 
@@ -697,7 +697,7 @@ class FakeApi {
     /// test inline additionalProperties
     ///
     /// 
-    Future<Response>testInlineAdditionalProperties(
+    Future<Response<void>> testInlineAdditionalProperties(
         BuiltMap<String, String> requestBody, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -742,7 +742,7 @@ class FakeApi {
     /// test json serialization of form data
     ///
     /// 
-    Future<Response>testJsonFormData(
+    Future<Response<void>> testJsonFormData(
         String param,
         String param2, { 
         CancelToken cancelToken,
@@ -789,7 +789,7 @@ class FakeApi {
     /// 
     ///
     /// To test the collection format in query parameters
-    Future<Response>testQueryParameterCollectionFormat(
+    Future<Response<void>> testQueryParameterCollectionFormat(
         BuiltList<String> pipe,
         BuiltList<String> ioutil,
         BuiltList<String> http,

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/api/fake_classname_tags123_api.dart

@@ -14,7 +14,7 @@ class FakeClassnameTags123Api {
     /// To test class name in snake case
     ///
     /// To test class name in snake case
-    Future<Response<Client>>testClassname(
+    Future<Response<Client>> testClassname(
         Client client, { 
         CancelToken cancelToken,
         Map<String, String> headers,

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/api/pet_api.dart

@@ -18,7 +18,7 @@ class PetApi {
     /// Add a new pet to the store
     ///
     /// 
-    Future<Response>addPet(
+    Future<Response<void>> addPet(
         Pet pet, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -69,7 +69,7 @@ class PetApi {
     /// Deletes a pet
     ///
     /// 
-    Future<Response>deletePet(
+    Future<Response<void>> deletePet(
         int petId, { 
         String apiKey,
         CancelToken cancelToken,
@@ -115,7 +115,7 @@ class PetApi {
     /// Finds Pets by status
     ///
     /// Multiple status values can be provided with comma separated strings
-    Future<Response<BuiltList<Pet>>>findPetsByStatus(
+    Future<Response<BuiltList<Pet>>> findPetsByStatus(
         BuiltList<String> status, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -174,7 +174,7 @@ class PetApi {
     /// Finds Pets by tags
     ///
     /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
-    Future<Response<BuiltList<Pet>>>findPetsByTags(
+    Future<Response<BuiltList<Pet>>> findPetsByTags(
         BuiltList<String> tags, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -233,7 +233,7 @@ class PetApi {
     /// Find pet by ID
     ///
     /// Returns a single pet
-    Future<Response<Pet>>getPetById(
+    Future<Response<Pet>> getPetById(
         int petId, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -292,7 +292,7 @@ class PetApi {
     /// Update an existing pet
     ///
     /// 
-    Future<Response>updatePet(
+    Future<Response<void>> updatePet(
         Pet pet, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -343,7 +343,7 @@ class PetApi {
     /// Updates a pet in the store with form data
     ///
     /// 
-    Future<Response>updatePetWithForm(
+    Future<Response<void>> updatePetWithForm(
         int petId, { 
         String name,
         String status,
@@ -396,7 +396,7 @@ class PetApi {
     /// uploads an image
     ///
     /// 
-    Future<Response<ApiResponse>>uploadFile(
+    Future<Response<ApiResponse>> uploadFile(
         int petId, { 
         String additionalMetadata,
         Uint8List file,
@@ -466,7 +466,7 @@ class PetApi {
     /// uploads an image (required)
     ///
     /// 
-    Future<Response<ApiResponse>>uploadFileWithRequiredFile(
+    Future<Response<ApiResponse>> uploadFileWithRequiredFile(
         int petId,
         Uint8List requiredFile, { 
         String additionalMetadata,

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/api/store_api.dart

@@ -15,7 +15,7 @@ class StoreApi {
     /// Delete purchase order by ID
     ///
     /// For valid response try integer IDs with value < 1000. Anything above 1000 or nonintegers will generate API errors
-    Future<Response>deleteOrder(
+    Future<Response<void>> deleteOrder(
         String orderId, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -54,7 +54,7 @@ class StoreApi {
     /// Returns pet inventories by status
     ///
     /// Returns a map of status codes to quantities
-    Future<Response<BuiltMap<String, int>>>getInventory({ 
+    Future<Response<BuiltMap<String, int>>> getInventory({ 
         CancelToken cancelToken,
         Map<String, String> headers,
         ProgressCallback onSendProgress,
@@ -113,7 +113,7 @@ class StoreApi {
     /// Find purchase order by ID
     ///
     /// For valid response try integer IDs with value <= 5 or > 10. Other values will generated exceptions
-    Future<Response<Order>>getOrderById(
+    Future<Response<Order>> getOrderById(
         int orderId, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -165,7 +165,7 @@ class StoreApi {
     /// Place an order for a pet
     ///
     /// 
-    Future<Response<Order>>placeOrder(
+    Future<Response<Order>> placeOrder(
         Order order, { 
         CancelToken cancelToken,
         Map<String, String> headers,

samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/api/user_api.dart

@@ -15,7 +15,7 @@ class UserApi {
     /// Create user
     ///
     /// This can only be done by the logged in user.
-    Future<Response>createUser(
+    Future<Response<void>> createUser(
         User user, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -60,7 +60,7 @@ class UserApi {
     /// Creates list of users with given input array
     ///
     /// 
-    Future<Response>createUsersWithArrayInput(
+    Future<Response<void>> createUsersWithArrayInput(
         BuiltList<User> user, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -106,7 +106,7 @@ class UserApi {
     /// Creates list of users with given input array
     ///
     /// 
-    Future<Response>createUsersWithListInput(
+    Future<Response<void>> createUsersWithListInput(
         BuiltList<User> user, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -152,7 +152,7 @@ class UserApi {
     /// Delete user
     ///
     /// This can only be done by the logged in user.
-    Future<Response>deleteUser(
+    Future<Response<void>> deleteUser(
         String username, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -191,7 +191,7 @@ class UserApi {
     /// Get user by user name
     ///
     /// 
-    Future<Response<User>>getUserByName(
+    Future<Response<User>> getUserByName(
         String username, { 
         CancelToken cancelToken,
         Map<String, String> headers,
@@ -243,7 +243,7 @@ class UserApi {
     /// Logs user into the system
     ///
     /// 
-    Future<Response<String>>loginUser(
+    Future<Response<String>> loginUser(
         String username,
         String password, { 
         CancelToken cancelToken,
@@ -297,7 +297,7 @@ class UserApi {
     /// Logs out current logged in user session
     ///
     /// 
-    Future<Response>logoutUser({ 
+    Future<Response<void>> logoutUser({ 
         CancelToken cancelToken,
         Map<String, String> headers,
         ProgressCallback onSendProgress,
@@ -335,7 +335,7 @@ class UserApi {
     /// Updated user
     ///
     /// This can only be done by the logged in user.
-    Future<Response>updateUser(
+    Future<Response<void>> updateUser(
         String username,
         User user, { 
         CancelToken cancelToken,

samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/pet_api.dart

@@ -95,7 +95,7 @@ class PetApi {
   ///   Pet id to delete
   ///
   /// * [String] apiKey:
-  Future deletePetWithHttpInfo(int petId, { String apiKey }) async {
+  Future<Response> deletePetWithHttpInfo(int petId, { String apiKey }) async {
     // Verify required params are set.
     if (petId == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: petId');
@@ -150,7 +150,7 @@ class PetApi {
   ///   Pet id to delete
   ///
   /// * [String] apiKey:
-  Future deletePet(int petId, { String apiKey }) async {
+  Future<void> deletePet(int petId, { String apiKey }) async {
     final response = await deletePetWithHttpInfo(petId,  apiKey: apiKey );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -472,7 +472,7 @@ class PetApi {
   ///
   /// * [String] status:
   ///   Updated status of the pet
-  Future updatePetWithFormWithHttpInfo(int petId, { String name, String status }) async {
+  Future<Response> updatePetWithFormWithHttpInfo(int petId, { String name, String status }) async {
     // Verify required params are set.
     if (petId == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: petId');
@@ -541,7 +541,7 @@ class PetApi {
   ///
   /// * [String] status:
   ///   Updated status of the pet
-  Future updatePetWithForm(int petId, { String name, String status }) async {
+  Future<void> updatePetWithForm(int petId, { String name, String status }) async {
     final response = await updatePetWithFormWithHttpInfo(petId,  name: name, status: status );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/store_api.dart

@@ -25,7 +25,7 @@ class StoreApi {
   ///
   /// * [String] orderId (required):
   ///   ID of the order that needs to be deleted
-  Future deleteOrderWithHttpInfo(String orderId) async {
+  Future<Response> deleteOrderWithHttpInfo(String orderId) async {
     // Verify required params are set.
     if (orderId == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: orderId');
@@ -76,7 +76,7 @@ class StoreApi {
   ///
   /// * [String] orderId (required):
   ///   ID of the order that needs to be deleted
-  Future deleteOrder(String orderId) async {
+  Future<void> deleteOrder(String orderId) async {
     final response = await deleteOrderWithHttpInfo(orderId);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/user_api.dart

@@ -25,7 +25,7 @@ class UserApi {
   ///
   /// * [User] user (required):
   ///   Created user object
-  Future createUserWithHttpInfo(User user) async {
+  Future<Response> createUserWithHttpInfo(User user) async {
     // Verify required params are set.
     if (user == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: user');
@@ -75,7 +75,7 @@ class UserApi {
   ///
   /// * [User] user (required):
   ///   Created user object
-  Future createUser(User user) async {
+  Future<void> createUser(User user) async {
     final response = await createUserWithHttpInfo(user);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -90,7 +90,7 @@ class UserApi {
   ///
   /// * [List<User>] user (required):
   ///   List of user object
-  Future createUsersWithArrayInputWithHttpInfo(List<User> user) async {
+  Future<Response> createUsersWithArrayInputWithHttpInfo(List<User> user) async {
     // Verify required params are set.
     if (user == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: user');
@@ -138,7 +138,7 @@ class UserApi {
   ///
   /// * [List<User>] user (required):
   ///   List of user object
-  Future createUsersWithArrayInput(List<User> user) async {
+  Future<void> createUsersWithArrayInput(List<User> user) async {
     final response = await createUsersWithArrayInputWithHttpInfo(user);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -153,7 +153,7 @@ class UserApi {
   ///
   /// * [List<User>] user (required):
   ///   List of user object
-  Future createUsersWithListInputWithHttpInfo(List<User> user) async {
+  Future<Response> createUsersWithListInputWithHttpInfo(List<User> user) async {
     // Verify required params are set.
     if (user == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: user');
@@ -201,7 +201,7 @@ class UserApi {
   ///
   /// * [List<User>] user (required):
   ///   List of user object
-  Future createUsersWithListInput(List<User> user) async {
+  Future<void> createUsersWithListInput(List<User> user) async {
     final response = await createUsersWithListInputWithHttpInfo(user);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -218,7 +218,7 @@ class UserApi {
   ///
   /// * [String] username (required):
   ///   The name that needs to be deleted
-  Future deleteUserWithHttpInfo(String username) async {
+  Future<Response> deleteUserWithHttpInfo(String username) async {
     // Verify required params are set.
     if (username == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: username');
@@ -269,7 +269,7 @@ class UserApi {
   ///
   /// * [String] username (required):
   ///   The name that needs to be deleted
-  Future deleteUser(String username) async {
+  Future<void> deleteUser(String username) async {
     final response = await deleteUserWithHttpInfo(username);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -432,7 +432,7 @@ class UserApi {
   /// Logs out current logged in user session
   ///
   /// Note: This method returns the HTTP [Response].
-  Future logoutUserWithHttpInfo() async {
+  Future<Response> logoutUserWithHttpInfo() async {
     final path = '/user/logout'.replaceAll('{format}', 'json');
 
     Object postBody;
@@ -470,7 +470,7 @@ class UserApi {
   }
 
   /// Logs out current logged in user session
-  Future logoutUser() async {
+  Future<void> logoutUser() async {
     final response = await logoutUserWithHttpInfo();
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -490,7 +490,7 @@ class UserApi {
   ///
   /// * [User] user (required):
   ///   Updated user object
-  Future updateUserWithHttpInfo(String username, User user) async {
+  Future<Response> updateUserWithHttpInfo(String username, User user) async {
     // Verify required params are set.
     if (username == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: username');
@@ -547,7 +547,7 @@ class UserApi {
   ///
   /// * [User] user (required):
   ///   Updated user object
-  Future updateUser(String username, User user) async {
+  Future<void> updateUser(String username, User user) async {
     final response = await updateUserWithHttpInfo(username, user);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/fake_api.dart

@@ -84,7 +84,7 @@ class FakeApi {
   ///
   /// * [String] header1:
   ///   header parameter
-  Future fakeHttpSignatureTestWithHttpInfo(Pet pet, { String query1, String header1 }) async {
+  Future<Response> fakeHttpSignatureTestWithHttpInfo(Pet pet, { String query1, String header1 }) async {
     // Verify required params are set.
     if (pet == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: pet');
@@ -146,7 +146,7 @@ class FakeApi {
   ///
   /// * [String] header1:
   ///   header parameter
-  Future fakeHttpSignatureTest(Pet pet, { String query1, String header1 }) async {
+  Future<void> fakeHttpSignatureTest(Pet pet, { String query1, String header1 }) async {
     final response = await fakeHttpSignatureTestWithHttpInfo(pet,  query1: query1, header1: header1 );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -428,7 +428,7 @@ class FakeApi {
   /// Parameters:
   ///
   /// * [FileSchemaTestClass] fileSchemaTestClass (required):
-  Future testBodyWithFileSchemaWithHttpInfo(FileSchemaTestClass fileSchemaTestClass) async {
+  Future<Response> testBodyWithFileSchemaWithHttpInfo(FileSchemaTestClass fileSchemaTestClass) async {
     // Verify required params are set.
     if (fileSchemaTestClass == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: fileSchemaTestClass');
@@ -475,7 +475,7 @@ class FakeApi {
   /// Parameters:
   ///
   /// * [FileSchemaTestClass] fileSchemaTestClass (required):
-  Future testBodyWithFileSchema(FileSchemaTestClass fileSchemaTestClass) async {
+  Future<void> testBodyWithFileSchema(FileSchemaTestClass fileSchemaTestClass) async {
     final response = await testBodyWithFileSchemaWithHttpInfo(fileSchemaTestClass);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -488,7 +488,7 @@ class FakeApi {
   /// * [String] query (required):
   ///
   /// * [User] user (required):
-  Future testBodyWithQueryParamsWithHttpInfo(String query, User user) async {
+  Future<Response> testBodyWithQueryParamsWithHttpInfo(String query, User user) async {
     // Verify required params are set.
     if (query == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: query');
@@ -540,7 +540,7 @@ class FakeApi {
   /// * [String] query (required):
   ///
   /// * [User] user (required):
-  Future testBodyWithQueryParams(String query, User user) async {
+  Future<void> testBodyWithQueryParams(String query, User user) async {
     final response = await testBodyWithQueryParamsWithHttpInfo(query, user);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -670,7 +670,7 @@ class FakeApi {
   ///
   /// * [String] callback:
   ///   None
-  Future testEndpointParametersWithHttpInfo(num number, double double_, String patternWithoutDelimiter, String byte, { int integer, int int32, int int64, double float, String string, MultipartFile binary, DateTime date, DateTime dateTime, String password, String callback }) async {
+  Future<Response> testEndpointParametersWithHttpInfo(num number, double double_, String patternWithoutDelimiter, String byte, { int integer, int int32, int int64, double float, String string, MultipartFile binary, DateTime date, DateTime dateTime, String password, String callback }) async {
     // Verify required params are set.
     if (number == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: number');
@@ -864,7 +864,7 @@ class FakeApi {
   ///
   /// * [String] callback:
   ///   None
-  Future testEndpointParameters(num number, double double_, String patternWithoutDelimiter, String byte, { int integer, int int32, int int64, double float, String string, MultipartFile binary, DateTime date, DateTime dateTime, String password, String callback }) async {
+  Future<void> testEndpointParameters(num number, double double_, String patternWithoutDelimiter, String byte, { int integer, int int32, int int64, double float, String string, MultipartFile binary, DateTime date, DateTime dateTime, String password, String callback }) async {
     final response = await testEndpointParametersWithHttpInfo(number, double_, patternWithoutDelimiter, byte,  integer: integer, int32: int32, int64: int64, float: float, string: string, binary: binary, date: date, dateTime: dateTime, password: password, callback: callback );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -902,7 +902,7 @@ class FakeApi {
   ///
   /// * [String] enumFormString:
   ///   Form parameter enum test (string)
-  Future testEnumParametersWithHttpInfo({ List<String> enumHeaderStringArray, String enumHeaderString, List<String> enumQueryStringArray, String enumQueryString, int enumQueryInteger, double enumQueryDouble, List<String> enumFormStringArray, String enumFormString }) async {
+  Future<Response> testEnumParametersWithHttpInfo({ List<String> enumHeaderStringArray, String enumHeaderString, List<String> enumQueryStringArray, String enumQueryString, int enumQueryInteger, double enumQueryDouble, List<String> enumFormStringArray, String enumFormString }) async {
     // Verify required params are set.
 
     final path = '/fake'.replaceAll('{format}', 'json');
@@ -1004,7 +1004,7 @@ class FakeApi {
   ///
   /// * [String] enumFormString:
   ///   Form parameter enum test (string)
-  Future testEnumParameters({ List<String> enumHeaderStringArray, String enumHeaderString, List<String> enumQueryStringArray, String enumQueryString, int enumQueryInteger, double enumQueryDouble, List<String> enumFormStringArray, String enumFormString }) async {
+  Future<void> testEnumParameters({ List<String> enumHeaderStringArray, String enumHeaderString, List<String> enumQueryStringArray, String enumQueryString, int enumQueryInteger, double enumQueryDouble, List<String> enumFormStringArray, String enumFormString }) async {
     final response = await testEnumParametersWithHttpInfo( enumHeaderStringArray: enumHeaderStringArray, enumHeaderString: enumHeaderString, enumQueryStringArray: enumQueryStringArray, enumQueryString: enumQueryString, enumQueryInteger: enumQueryInteger, enumQueryDouble: enumQueryDouble, enumFormStringArray: enumFormStringArray, enumFormString: enumFormString );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -1036,7 +1036,7 @@ class FakeApi {
   ///
   /// * [int] int64Group:
   ///   Integer in group parameters
-  Future testGroupParametersWithHttpInfo(int requiredStringGroup, bool requiredBooleanGroup, int requiredInt64Group, { int stringGroup, bool booleanGroup, int int64Group }) async {
+  Future<Response> testGroupParametersWithHttpInfo(int requiredStringGroup, bool requiredBooleanGroup, int requiredInt64Group, { int stringGroup, bool booleanGroup, int int64Group }) async {
     // Verify required params are set.
     if (requiredStringGroup == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: requiredStringGroup');
@@ -1121,7 +1121,7 @@ class FakeApi {
   ///
   /// * [int] int64Group:
   ///   Integer in group parameters
-  Future testGroupParameters(int requiredStringGroup, bool requiredBooleanGroup, int requiredInt64Group, { int stringGroup, bool booleanGroup, int int64Group }) async {
+  Future<void> testGroupParameters(int requiredStringGroup, bool requiredBooleanGroup, int requiredInt64Group, { int stringGroup, bool booleanGroup, int int64Group }) async {
     final response = await testGroupParametersWithHttpInfo(requiredStringGroup, requiredBooleanGroup, requiredInt64Group,  stringGroup: stringGroup, booleanGroup: booleanGroup, int64Group: int64Group );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -1136,7 +1136,7 @@ class FakeApi {
   ///
   /// * [Map<String, String>] requestBody (required):
   ///   request body
-  Future testInlineAdditionalPropertiesWithHttpInfo(Map<String, String> requestBody) async {
+  Future<Response> testInlineAdditionalPropertiesWithHttpInfo(Map<String, String> requestBody) async {
     // Verify required params are set.
     if (requestBody == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: requestBody');
@@ -1184,7 +1184,7 @@ class FakeApi {
   ///
   /// * [Map<String, String>] requestBody (required):
   ///   request body
-  Future testInlineAdditionalProperties(Map<String, String> requestBody) async {
+  Future<void> testInlineAdditionalProperties(Map<String, String> requestBody) async {
     final response = await testInlineAdditionalPropertiesWithHttpInfo(requestBody);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -1202,7 +1202,7 @@ class FakeApi {
   ///
   /// * [String] param2 (required):
   ///   field2
-  Future testJsonFormDataWithHttpInfo(String param, String param2) async {
+  Future<Response> testJsonFormDataWithHttpInfo(String param, String param2) async {
     // Verify required params are set.
     if (param == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: param');
@@ -1270,7 +1270,7 @@ class FakeApi {
   ///
   /// * [String] param2 (required):
   ///   field2
-  Future testJsonFormData(String param, String param2) async {
+  Future<void> testJsonFormData(String param, String param2) async {
     final response = await testJsonFormDataWithHttpInfo(param, param2);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -1292,7 +1292,7 @@ class FakeApi {
   /// * [List<String>] url (required):
   ///
   /// * [List<String>] context (required):
-  Future testQueryParameterCollectionFormatWithHttpInfo(List<String> pipe, List<String> ioutil, List<String> http, List<String> url, List<String> context) async {
+  Future<Response> testQueryParameterCollectionFormatWithHttpInfo(List<String> pipe, List<String> ioutil, List<String> http, List<String> url, List<String> context) async {
     // Verify required params are set.
     if (pipe == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: pipe');
@@ -1365,7 +1365,7 @@ class FakeApi {
   /// * [List<String>] url (required):
   ///
   /// * [List<String>] context (required):
-  Future testQueryParameterCollectionFormat(List<String> pipe, List<String> ioutil, List<String> http, List<String> url, List<String> context) async {
+  Future<void> testQueryParameterCollectionFormat(List<String> pipe, List<String> ioutil, List<String> http, List<String> url, List<String> context) async {
     final response = await testQueryParameterCollectionFormatWithHttpInfo(pipe, ioutil, http, url, context);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/pet_api.dart

@@ -23,7 +23,7 @@ class PetApi {
   ///
   /// * [Pet] pet (required):
   ///   Pet object that needs to be added to the store
-  Future addPetWithHttpInfo(Pet pet) async {
+  Future<Response> addPetWithHttpInfo(Pet pet) async {
     // Verify required params are set.
     if (pet == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: pet');
@@ -71,7 +71,7 @@ class PetApi {
   ///
   /// * [Pet] pet (required):
   ///   Pet object that needs to be added to the store
-  Future addPet(Pet pet) async {
+  Future<void> addPet(Pet pet) async {
     final response = await addPetWithHttpInfo(pet);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -88,7 +88,7 @@ class PetApi {
   ///   Pet id to delete
   ///
   /// * [String] apiKey:
-  Future deletePetWithHttpInfo(int petId, { String apiKey }) async {
+  Future<Response> deletePetWithHttpInfo(int petId, { String apiKey }) async {
     // Verify required params are set.
     if (petId == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: petId');
@@ -143,7 +143,7 @@ class PetApi {
   ///   Pet id to delete
   ///
   /// * [String] apiKey:
-  Future deletePet(int petId, { String apiKey }) async {
+  Future<void> deletePet(int petId, { String apiKey }) async {
     final response = await deletePetWithHttpInfo(petId,  apiKey: apiKey );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -389,7 +389,7 @@ class PetApi {
   ///
   /// * [Pet] pet (required):
   ///   Pet object that needs to be added to the store
-  Future updatePetWithHttpInfo(Pet pet) async {
+  Future<Response> updatePetWithHttpInfo(Pet pet) async {
     // Verify required params are set.
     if (pet == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: pet');
@@ -437,7 +437,7 @@ class PetApi {
   ///
   /// * [Pet] pet (required):
   ///   Pet object that needs to be added to the store
-  Future updatePet(Pet pet) async {
+  Future<void> updatePet(Pet pet) async {
     final response = await updatePetWithHttpInfo(pet);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -458,7 +458,7 @@ class PetApi {
   ///
   /// * [String] status:
   ///   Updated status of the pet
-  Future updatePetWithFormWithHttpInfo(int petId, { String name, String status }) async {
+  Future<Response> updatePetWithFormWithHttpInfo(int petId, { String name, String status }) async {
     // Verify required params are set.
     if (petId == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: petId');
@@ -527,7 +527,7 @@ class PetApi {
   ///
   /// * [String] status:
   ///   Updated status of the pet
-  Future updatePetWithForm(int petId, { String name, String status }) async {
+  Future<void> updatePetWithForm(int petId, { String name, String status }) async {
     final response = await updatePetWithFormWithHttpInfo(petId,  name: name, status: status );
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/store_api.dart

@@ -25,7 +25,7 @@ class StoreApi {
   ///
   /// * [String] orderId (required):
   ///   ID of the order that needs to be deleted
-  Future deleteOrderWithHttpInfo(String orderId) async {
+  Future<Response> deleteOrderWithHttpInfo(String orderId) async {
     // Verify required params are set.
     if (orderId == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: orderId');
@@ -76,7 +76,7 @@ class StoreApi {
   ///
   /// * [String] orderId (required):
   ///   ID of the order that needs to be deleted
-  Future deleteOrder(String orderId) async {
+  Future<void> deleteOrder(String orderId) async {
     final response = await deleteOrderWithHttpInfo(orderId);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));

samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/user_api.dart

@@ -25,7 +25,7 @@ class UserApi {
   ///
   /// * [User] user (required):
   ///   Created user object
-  Future createUserWithHttpInfo(User user) async {
+  Future<Response> createUserWithHttpInfo(User user) async {
     // Verify required params are set.
     if (user == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: user');
@@ -75,7 +75,7 @@ class UserApi {
   ///
   /// * [User] user (required):
   ///   Created user object
-  Future createUser(User user) async {
+  Future<void> createUser(User user) async {
     final response = await createUserWithHttpInfo(user);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -90,7 +90,7 @@ class UserApi {
   ///
   /// * [List<User>] user (required):
   ///   List of user object
-  Future createUsersWithArrayInputWithHttpInfo(List<User> user) async {
+  Future<Response> createUsersWithArrayInputWithHttpInfo(List<User> user) async {
     // Verify required params are set.
     if (user == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: user');
@@ -138,7 +138,7 @@ class UserApi {
   ///
   /// * [List<User>] user (required):
   ///   List of user object
-  Future createUsersWithArrayInput(List<User> user) async {
+  Future<void> createUsersWithArrayInput(List<User> user) async {
     final response = await createUsersWithArrayInputWithHttpInfo(user);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -153,7 +153,7 @@ class UserApi {
   ///
   /// * [List<User>] user (required):
   ///   List of user object
-  Future createUsersWithListInputWithHttpInfo(List<User> user) async {
+  Future<Response> createUsersWithListInputWithHttpInfo(List<User> user) async {
     // Verify required params are set.
     if (user == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: user');
@@ -201,7 +201,7 @@ class UserApi {
   ///
   /// * [List<User>] user (required):
   ///   List of user object
-  Future createUsersWithListInput(List<User> user) async {
+  Future<void> createUsersWithListInput(List<User> user) async {
     final response = await createUsersWithListInputWithHttpInfo(user);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -218,7 +218,7 @@ class UserApi {
   ///
   /// * [String] username (required):
   ///   The name that needs to be deleted
-  Future deleteUserWithHttpInfo(String username) async {
+  Future<Response> deleteUserWithHttpInfo(String username) async {
     // Verify required params are set.
     if (username == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: username');
@@ -269,7 +269,7 @@ class UserApi {
   ///
   /// * [String] username (required):
   ///   The name that needs to be deleted
-  Future deleteUser(String username) async {
+  Future<void> deleteUser(String username) async {
     final response = await deleteUserWithHttpInfo(username);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -432,7 +432,7 @@ class UserApi {
   /// Logs out current logged in user session
   ///
   /// Note: This method returns the HTTP [Response].
-  Future logoutUserWithHttpInfo() async {
+  Future<Response> logoutUserWithHttpInfo() async {
     final path = '/user/logout'.replaceAll('{format}', 'json');
 
     Object postBody;
@@ -470,7 +470,7 @@ class UserApi {
   }
 
   /// Logs out current logged in user session
-  Future logoutUser() async {
+  Future<void> logoutUser() async {
     final response = await logoutUserWithHttpInfo();
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));
@@ -490,7 +490,7 @@ class UserApi {
   ///
   /// * [User] user (required):
   ///   Updated user object
-  Future updateUserWithHttpInfo(String username, User user) async {
+  Future<Response> updateUserWithHttpInfo(String username, User user) async {
     // Verify required params are set.
     if (username == null) {
      throw ApiException(HttpStatus.badRequest, 'Missing required param: username');
@@ -547,7 +547,7 @@ class UserApi {
   ///
   /// * [User] user (required):
   ///   Updated user object
-  Future updateUser(String username, User user) async {
+  Future<void> updateUser(String username, User user) async {
     final response = await updateUserWithHttpInfo(username, user);
     if (response.statusCode >= HttpStatus.badRequest) {
       throw ApiException(response.statusCode, _decodeBodyBytes(response));