'npm run test' works, but 'jest --coverage' command does not work

Question

I have MonoRepo project (using Lerna ) which consists of multiple packages, and one of them is a React application.

Within the React project package, I utilise Jest for unit testing. However, when I run the jest --coverage command on the WebStorm console, it returns me the following error:

zsh: command not found: jest

Strangely enough, if I use npm run test , the test runs, and my test coverage report is generated. Here is part of my package.json :

"scripts": {
  "test": "jest --coverage",
  // other stuff
},

As you can see, npm run test runs jest --coverage , which is the exact command I initially entered. Why won't the jest command work on its own?

Answer 1

You need to run it directly from your node_modules like this:

./node_modules/.bin/jest --coverage

See https://jestjs.io/docs/en/getting-started#running-from-command-line for more information

Answer 2

最直接的解决方案是全局安装 jest：

npm i -g jest