Flutter 测试：如何定位（特定）小部件

Question

我正在测试移动应用部门创建的应用程序。

几乎没有任何小部件有任何键或标签来区分彼此。

即使针对单个小部件，我也很难把握时机，更不用说同一页面上的 2 个类似的小部件了；示例：2 个文本字段小部件：用户名、密码。

现在，我唯一的测试是这个：

testWidgets('Empty Login Box', (WidgetTester tester) async {
    app.main();
    
    await tester.pumpAndSettle();
    
    final emailText = find.text("EMAIL");
    expect(emailText, findsOneWidget);
    
    });

甚至这个也不起作用。这是回应：

00:40 +0: ...\EndevStudios\MedicalApp\gshDevWork\medical-app-frontend\integration_test\mock_image_upload_test.dart     I00:43 +0: ...\EndevStudios\MedicalApp\gshDevWork\medical-app-frontend\integration_test\mock_image_upload_test.d 2,854ms
00:47 +0: Login Page Tests Empty Login Box
══╡ EXCEPTION CAUGHT BY FLUTTER TEST FRAMEWORK ╞════════════════════════════════════════════════════
The following TestFailure was thrown running a test:
Expected: exactly one matching node in the widget tree
  Actual: _TextFinder:<zero widgets with text "EMAIL" (ignoring offstage widgets)>
   Which: means none were found but one was expected

When the exception was thrown, this was the stack:
#4      main.<anonymous closure>.<anonymous closure> (file:///D:/WEBDEV/EndevStudios/MedicalApp/gshDevWork/medical-app-frontend/integration_test/mock_image_upload_test.dart:29:7)
<asynchronous suspension>
<asynchronous suspension>
(elided one frame from package:stack_trace)

This was caught by the test expectation on the following line:
  file:///D:/WEBDEV/EndevStudios/MedicalApp/gshDevWork/medical-app-frontend/integration_test/mock_image_upload_test.dart line 29
The test description was:
  Empty Login Box
════════════════════════════════════════════════════════════════════════════════════════════════════
00:47 +0 -1: Login Page Tests Empty Login Box [E]
  Test failed. See exception logs above.
  The test description was: Empty Login Box

00:48 +0 -1: Some tests failed.

我一直在尝试使用这些 CommonFinders 类，但我似乎无法有效地利用它们。

https://docs.flutter.dev/cookbook/testing/widget/finders
https://api.flutter.dev/flutter/flutter_driver/CommonFinders-class.html
https://api.flutter.dev/flutter/flutter_test/CommonFinders-class.html

对于任何有能力的人，请帮忙！

Answer 1

您需要首先泵送您的小部件，如果不这样做，Finder 将无法找到您的小部件并会出错：

运行测试时抛出以下 TestFailure：预期：完全正确
小部件树中的一个匹配节点实际：_TextFinder：<零
带有文本“EMAIL”的小部件（忽略后台小部件）>其中：意味着
没有找到，但预计有一个

尝试以下代码：

  testWidgets('Empty Login Box', (WidgetTester tester) async {
    /// Pump your widget first:
    await tester.pumpWidget(const LoginBoxWidget(
      title: 'My Title',
      message: 'Another parameter...',
    )); // Parameters depend on your widget

    final emailText = find.text("EMAIL");
    expect(emailText, findsOneWidget);
  });