yarn run

Runs a defined package script.

You may define scripts in your package.json file.

{
  "name": "my-package",
  "scripts": {
    "build": "babel src -d lib",
    "test": "jest"
  }
}

If you have defined a scripts object in your package, this command will run the specified [script]. For example:

yarn run test

Running this command will execute the script named "test" in your package.json.

You can pass additional arguments to your script by using --.

yarn run test -- -o --watch

Running this command will execute jest -o --watch.

[script] can also be any locally installed executable that is inside node_modules/.bin/.

Running this command will list environment variables available to the scripts at runtime.

If you want to override this command, you can do so by defining your own "env" script in package.json.

If you do not specify a script to the yarn run command, the run command will list all of the scripts available to run for a package.