gecko-dev/tools/lint/eslint.yml

eslint:
    description: JavaScript linter
    # ESLint infra handles its own path filtering, so just include cwd
    include: ['.']
    exclude: []
    # Make sure these are defined on the same line until the hack
    # in hook_helper.py is fixed.
    extensions: ['js', 'jsm', 'jsx', 'xml', 'html', 'xhtml']
    type: external
    payload: eslint:lint