What is the test command while creating package.json?

Question

While creating package.json from command line using npm init for creating a module in Node.js, there is a test command field that I don't know about. There's no mention of it in the docs too on executing npm help json also in the CLI.

Please explain what it is about.

Answer 1

The test command is the command that is run whenever you call npm test.

This is important when integrating with continuous integration/continuous deployment tools (such as jenkins, codeship, teamcity).

Example:
- say you deploy a project to AWS or some other cloud hosting provider,
- you can set up your infrastructure to automatically run npm test.
- If there are problems within those tests, your ci/cd will automatically rollback before deploying.

To execute tests
You can use karma, jest, or selenium/nightmare/phantomjs or about any other test scripting library/framework that allows you to write and execute tests and then set the required command in scripts.test and finally run it from npm test.