使用react-testing library的Render方法不起作用

Question

我尝试测试react-testing-library文档中提供的基本示例。我准确地复制并粘贴了这段代码here

无论发生什么，它都会失败。

下面是失败的测试结果：

shows the children when the checkbox is checked

    TypeError: Cannot read property 'current' of undefined

      34 | test('shows the children when the checkbox is checked', () => {
      35 |   const testMessage = 'Test Message'
    > 36 |   const {queryByText, getByLabelText, getByText} = render(
         |                                                    ^
      37 |     <HiddenMessage>{testMessage}</HiddenMessage>,
      38 |   )
      39 | 

      at act (node_modules/react-dom/cjs/react-dom-test-utils.development.js:983:55)
      at act (node_modules/react-dom/cjs/react-dom-test-utils.development.js:1418:12)
      at render (node_modules/@testing-library/react/dist/pure.js:82:26)
      at Object.<anonymous> (src/components/Authentication/SignUp/index.test.js:36:52)

  ● shows the children when the checkbox is checked

    TypeError: Cannot read property 'current' of undefined

      at act (node_modules/react-dom/cjs/react-dom-test-utils.development.js:983:55)
      at act (node_modules/react-dom/cjs/react-dom-test-utils.development.js:1418:12)
      at node_modules/@testing-library/react/dist/act-compat.js:57:20
      at asyncAct (node_modules/@testing-library/react/dist/act-compat.js:38:14)
      at Object.<anonymous> (node_modules/@testing-library/react/dist/index.js:28:35)

Test Suites: 1 failed, 1 total
Tests:       1 failed, 1 total
Snapshots:   0 total
Time:        2.318s, estimated 3s
Ran all test suites related to changed files.

有什么想法吗？

Answer 1

我也遇到了这一点，从我的研究来看，current调用的undefined似乎是https://github.com/facebook/react/blob/master/packages/react-dom/src/test-utils/ReactTestUtilsAct.js#L79内部的IsSomeRendererActing

它看起来像是在react包之间共享的全局变量。我能给出的最好的建议是检查react dom react和react test utils以及任何其他的react包都是同一版本。

Answer 2

此错误可能来自HiddenMessage组件内部，而不是测试代码中的任何错误。看起来您正在尝试访问不存在的东西(可能是ref?)上的current。

测试代码看起来是正确的，您应该跟踪您尝试在HiddenMessage中访问current的位置。