Home » Electric Practices Ideas » How Do I Test a Single File Using Jest?

How Do I Test a Single File Using Jest?

Alexander Ross • • 10 min read
How Do I Test a Single File Using Jest?

I am able to test multiple files using Jest, but I cannot figure out how to test a single file.

I have:

  • Run npm install jest-cli --save-dev
  • Updated package.json: `{ ... "scripts": { "test": "jest" } ... }
  • Written a number of tests.

Running npm test works as expected (currently it runs 14 tests).

How do I test a single file, e.g. test app/foo/__tests__/bar.spec.js?

I have tried running npm test app/foo/__tests__/bar.spec.js (from the project root), but I get the following error:

npm ERR! Error: ENOENT, open '/node_modules/app/foo/tests/

1

32 Answers

1
2

Since at least 2019:

npm test -- bar.spec.js

Alexander Ross
Author

Alexander Ross

Alexander Ross has covered the video game industry for a decade, writing deep dives on game design, esports tournaments, VR developments, and gaming culture.