如何截断方法的回调

Question

我在Flutter项目中使用Firebase Phone Auth，并想测试我的Auth类。我知道如何将Mockito的when()和.thenAnswer()与典型的Futures一起使用。

我想测试我的身份验证方法，特别是verificationFailed和verificationCompleted回调。

Future<void> getSmsCodeWithFirebase() async {
try {
await _firebaseAuth.verifyPhoneNumber(
phoneNumber: fullPhoneNumber,
timeout: const Duration(seconds: 30), 
verificationCompleted: (credential) async {
_firebaseSignIn(credential);
},
verificationFailed: (e) {
errorMessage = 'Error code: ${e.code}';
}
initModelState = DataState.error;
},
codeSent: (String verificationId, int resendToken) {
_firebaseSessionId = verificationId;
initModelState = DataState.idle;
},
codeAutoRetrievalTimeout: (String verificationId) {},
);
} catch (ex) {
errorMessage = 'There was some error';
updateModelState = DataState.error;
}
}

现在我想到了这样的东西，但我不知道如何调用传递的回调。

test('cant verify phonenumber', () async {
when(mockFirebaseAuth.verifyPhoneNumber(
phoneNumber: any,
codeSent: anyNamed('codeSent'),
verificationCompleted: anyNamed('verificationCompleted'),
verificationFailed: anyNamed('verificationFailed'),
codeAutoRetrievalTimeout: anyNamed('codeAutoRetrievalTimeout')))
.thenAnswer((Invocation invocation) {
// I need to put something here?
});
await authCodeViewModel.getSmsCodeWithFirebase();
expect(authCodeViewModel.initModelState, DataState.error);
});

Answer 1

您实际上并不是在问如何存根回调本身；您正在询问如何为存根方法调用回调。您将使用与任何其他捕获参数相同的捕获回调参数：

// Sample class with a method that takes a callback.
abstract class Foo {
void f(String Function(int x) callback, int y);
}
@GenerateMocks([Foo])
void main() {
var mockFoo = MockFoo();
mockFoo.f((x) => '$x', 42);
var captured = verify(mockFoo.f(captureAny, any)).captured;
var f = captured[0] as String Function(int);
print(f(88)); // Prints: 88
}

在你的情况下，我认为它会像：

test('cant verify phonenumber', () async {
await authCodeViewModel.getSmsCodeWithFirebase();
var captured = verify(mockFirebaseAuth.verifyPhoneNumber(
phoneNumber: any,
codeSent: anyNamed('codeSent'),
verificationCompleted: anyNamed('verificationCompleted'),
verificationFailed: captureNamed('verificationFailed'),
codeAutoRetrievalTimeout: anyNamed('codeAutoRetrievalTimeout')))
.captured;
var verificationFailed = captured[0] as PhoneVerificationFailed;
verificationFailed(FirebaseAuthException());
expect(authCodeViewModel.initModelState, DataState.error);
});

当然，如果您提供回调，那么您一开始就不需要捕获它们；你可以自己直接调用它们。