可以运行 React App 或使用 babel-jest 对其进行测试

Question

I am trying to set up tests for the existing React app. We are using React 16.8.13 After some struggle I've made it work. For that I had to install jest 24.9.0 and babel-jest 24.9.0 . The tests run fine and I am getting a coverage report. However when I run yarn start I am getting an error:

The react-scripts package provided by Create React App requires a dependency:

  "babel-jest": "23.6.0"

Don't try to install it manually: your package manager does it automatically.
However, a different version of babel-jest was detected higher up in the tree:

  /<Path to my App>/node_modules/babel-jest (version: 24.9.0) 

removing both jest and babel-jest from devDependencies fixes the issue, but now running yarn test gives me an error:

No tests found
In /<Path to my App>
  32 files checked.
  testMatch:  - 32 matches
  testPathIgnorePatterns: /node_modules/ - 32 matches
  testRegex: (\/tests\/.*\.test)\.[jt]sx?$ - 0 matches
Pattern:  - 0 matches
error Command failed with exit code 1.

What do I need to do to have both app and tests runnable?

Answer 1

Based on the No tests found , it looks like your tests might not be in the right folder. They should be in a folder in src called __tests__ and have a test.js or spec.js suffix.

See this answer for more info: Create React App cannot find tests