Bad state: Mock method was not called within `when()`. Was a real method called?

Question

I'm trying to make a mock of an httpRequest in flutter using mockito.

Here I define a global http client:

library utgard.globals;

import 'package:http/http.dart' as http;

http.Client httpClient = http.Client();

Then I replace in integration testing:

import 'package:flutter_driver/driver_extension.dart';
import 'package:http/http.dart' as http;
import 'package:utgard/globals.dart' as globals;
import 'package:mockito/mockito.dart';

import 'package:utgard/main.dart' as app;

class MockClient extends Mock implements http.Client {}

void main() {
  final MockClient client = MockClient();
  globals.httpClient = client;

  enableFlutterDriverExtension();

  app.main();
}

Then I try to use when of mockito:

test('login with correct password', () async {
      final client = MockClient();

      when(globals.httpClient.post('http://www.google.com'))
          .thenAnswer((_) async => http.Response('{"title": "Test"}', 200));

      await driver.enterText('000000');
      await driver.tap(loginContinuePasswordButton);
    });

But I receive the following error:

Bad state: Mock method was not called within when(). Was a real method called?

Andrey Gordeev · Accepted Answer · 2019-09-10 12:26:05Z

52

This issue may happen when you implement a method you want to mock instead of letting Mockito do that.

This code below will return Bad state: Mock method was not called within when(). Was a real method called?:

class MockFirebaseAuth extends Mock implements FirebaseAuth {
  FirebaseUser _currentUser;

  MockFirebaseAuth(this._currentUser);

  // This method causes the issue.
  Future<FirebaseUser> currentUser() async {
    return _currentUser;
  }
}

final user = MockFirebaseUser();
final mockFirebaseAuth = MockFirebaseAuth(user);

// Will throw `Bad state: Mock method was not called within `when()`. Was a real method called?`
when(mockFirebaseAuth.currentUser())
    .thenAnswer((_) => Future.value(user));

What do you want instead is:

class MockFirebaseAuth extends Mock implements FirebaseAuth {}

final user = MockFirebaseUser();
final mockFirebaseAuth = MockFirebaseAuth();

// Will work as expected
when(mockFirebaseAuth.currentUser())
    .thenAnswer((_) => Future.value(user));

Also this issue happens when you try to call when() on a non-mock sublass:

class MyClass {
  String doSomething() {
    return 'test';
  }
}

final myClassInstance = MyClass();

// Will throw `Bad state: Mock method was not called within `when()`. Was a real method called?`
when(myClassInstance.doSomething())
    .thenReturn((_) => 'mockedValue');

edited Sep 10, 2019 at 12:26

answered Aug 30, 2019 at 13:59

Andrey Gordeev

32.7k16 gold badges143 silver badges169 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Michel Feinstein Over a year ago

In my case I want to mock toString() so I can see the errors more clearly, not just the class names, but toString() is already defined from Mock itself.

CruorVult Over a year ago

One more case if you try to mock mixin method.

Wahab Khan Jadon Jan 18 at 15:59

I made a silly mistake ... instead of assigning the MockClass instance I just assigned the actual class instance...

Rahul · Accepted Answer · 2021-09-22 10:49:53Z

3

There is one more possibility. If this happens to your mock object, then probably it may be outdated. In this case, try regenerating your mock objects by using

flutter pub run build_runner build --delete-conflicting-outputs

answered Sep 22, 2021 at 10:49

Rahul

2432 silver badges9 bronze badges

Comments

ary boby · Accepted Answer · 2023-02-13 07:18:53Z

0

please declare resetMocktailState() in teardown or at the end of setup, so the test cases should not affect later test cases.

answered Feb 13, 2023 at 7:18

ary boby

1

Comments

Felipe Augusto · Accepted Answer · 2019-06-08 06:27:30Z

The solution I found was to define the mock in test_driver/app.dart and call the runApp function after that, this way you can apply the mock even with flutter integration testing:

import 'package:flutter/widgets.dart';
import 'package:flutter_driver/driver_extension.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:utgard/business/config/globals.dart';
import 'package:utgard/main.dart' as app;

class MockClient extends Mock implements http.Client {}

void main() {
  enableFlutterDriverExtension();

  final MockClient client = MockClient();
  // make your mocks here
  httpClient = client;

  runApp(app.MyApp());
}

Since it can become a huge code to mock all the requests there you can make a separate function in order to better organize the code:

import 'package:flutter/widgets.dart';
import 'package:flutter_driver/driver_extension.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:utgard/business/config/globals.dart';
import 'package:utgard/main.dart' as app;

class MockClient extends Mock implements http.Client {}

void main() {
  enableFlutterDriverExtension();

  final MockClient client = MockClient();
  makeMock();
  httpClient = client;

  runApp(app.MyApp());
}

Collectives™ on Stack Overflow

Bad state: Mock method was not called within `when()`. Was a real method called?

4 Answers 4

3 Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

3 Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related