How do I enable watch-all-tests?

[ffMathy]

In the documentation, the mode watch-all-tests is mentioned as an alternative to just watch-tests. In other words, something that'll trigger --watchAll instead of --watch.

But how is this configured? The documentation doesn't state how.

[connectdotz]

You could customize the jest.jestCommandLine to append --watchAll there. Please also make sure your autoRun is not in watch mode, otherwise, it will override the --watchAll flag.

For example: in settings.json

{
"jest.jestCommandLine": "yarn jest --watchAll",
"jest.autoRun": "on-save",
}