gitlab-org--gitlab-foss/app/assets/javascripts/image_diff/view_types.js

export const viewTypes = {
  TWO_UP: 'TWO_UP',
  SWIPE: 'SWIPE',
  ONION_SKIN: 'ONION_SKIN',
};

export function isValidViewType(validate) {
  return Boolean(Object.getOwnPropertyNames(viewTypes).find((viewType) => viewType === validate));
}