mockito_extensions.dart

/// mocking the PostExpectation with a Future
extension FutureMock<T> on PostExpectation<Future<T>> {
  void thenFuture(T body) {
    thenAnswer((realInvocation) => Future.value(body));
  }
}

/// we use Result objet similar than a monad which returns a success, a failure, etc
/// this extension mocks a Result of success, failure or in order
extension ResultMock<T> on PostExpectation<Future<Result<T>>> {
  void thenSucceed(T body) {
    final result = Result.success(body);
    thenAnswer((realInvocation) => Future.value(result));
  }

  void thenFail([String message = 'mock-error']) {
    final result = Result<T>.failureWithMessage(message);
    thenAnswer((realInvocation) => Future.value(result));
  }

  void thenResultInOrder(List<Result<T>> results) {
    final availableResults = Queue.of(results);
    thenAnswer((_) => Future.value(availableResults.removeFirst()));
  }

  void thenFailWithCause(Error cause) {
    final result = Result<T>.failure(cause);
    thenAnswer((realInvocation) => Future.value(result));
  }
}

/// in some scenarios we use Streams, then to mock a stream response of any type
/// we use this extension
extension StreamMock<T> on PostExpectation<Stream<T>> {
  void thenStream(T body) {
    thenAnswer((realInvocation) => Stream.value(body));
  }

  void thenEmpty() {
    thenAnswer((realInvocation) => const Stream.empty());
  }
}

/// this mocks a response from an endpoint comsumption or a failure
/// we use a helper `buildSuccessResponse` method to build a response
extension ResponseResultMock<T> on PostExpectation<Future<Response<T>>> {
  void thenSucceed(T body) {
    thenAnswer((realInvocation) => Future.value(buildSuccessResponse(body)));
  }

  void thenFail({String message = 'mock-error', int statusCode = 400}) {
    thenAnswer(
      (realInvocation) => Future.value(
        buildFailureResponse(message, code: statusCode),
      ),
    );
  }
}