Flutter:如何正确实现FlutterError.OnError

时间:2019-01-21 17:02:27

标签: dart flutter flutter-test

有人可以告诉我如何在小部件测试期间实现最重要的抖动错误,以便我可以检查自己的自定义错误。

我在网上看到一些片段提到了这一点,但是我所有的实现都失败了

void main() {

  testWidgets('throws an error when scanning unknown term types', (WidgetTester tester) async {
    await tester.pumpWidget(injectTestWidget(new ItemScanScreen()));

    await tester.enterText(find.byKey(new Key('term')), '');
    await tester.tap(find.byIcon(Icons.send));
    await tester.pump();

    expect(
      tester.takeException(),
      isInstanceOf<UnrecognizedTermException>(),
      reason: 'should have thrown an UnrecognizedTermException error but didn\'t',
    );
  });
}

即使看起来实际上“抓住”了我的错误,上面的代码也会失败,并显示以下消息:

The following UnrecognizedTermException was thrown running a test:
Instance of 'UnrecognizedTermException'
...

我读到您可以执行以下代码段,但它看不到如何/在哪里实现:

final errorHandled = expectAsync0((){});

FlutterError.onError = (errorDetails) {
  // handle error
  errorHandled();
});

2 个答案:

答案 0 :(得分:1)

我在生产环境中使用下面的代码将错误记录到服务器上。

main.dart:

<Image width="125" className="rounded mx-auto d-block" src="/staff_login.jpg" />

logging.dart:

import 'dart:async';
import 'package:flutter/material.dart';
import 'logging.dart';

void main() async {
  FlutterError.onError = (FlutterErrorDetails details) async {
    new ErrorLogger().logError(details);
  };
  runZoned<Future<void>>(() async {
    // Your App Here
    runApp(MainApp());
  }, onError: (error, stackTrace) {
    new ErrorLogger().log(error, stackTrace);
  });
}

答案 1 :(得分:0)

这是用于测试的设计。我切换到try / catch中的包装逻辑,然后在“错误消息文本”当前概念上运行Expect()。例如:

try {
   throw new UnrecognizedTermException();
 } catch (e) {
   setState(() => _status = e.errMsg());
}

// then in my test
expect(find.text('Could not determine the type of item you scanned'), findsOneWidget);