Flutter:如何正确实现FlutterError.OnError [英] Flutter: How to implement FlutterError.OnError correctly

问题描述

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.

Can someone show me how to implement overriding flutter errors during widget test so I can check for my own custom errors.

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

I have seen snippets online mentioning this but all of my implementations fail

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 code above fails with the message below even though it looks like it in fact 'caught' my error:

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

我读到您可以执行下面的代码片段，但是它看不到如何/在何处实现它:

I read that you could do something like the snippet below but it did not see how/where to implement it:

final errorHandled = expectAsync0((){});

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

推荐答案

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:

This is was design for a test. I switched to wrapping logic in try/catch then running expect() on the "error message text" present concept. ex:

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);

这篇关于Flutter:如何正确实现FlutterError.OnError的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！