ex_icons-8.x-1.0/tests/modules/ex_icons_test/ex_icons_test.routing.yml

ex_icons_test.icon_selection:
  path: '/ex-icons-test/icon-selection'
  defaults:
    _form: '\Drupal\ex_icons_test\Form\ExIconsTestIconSelectionForm'
    _title: 'Icon selection'
  requirements:
    _access: 'TRUE'