packages/victory-core/src/victory-util/data.js
function getCategories(props, axis) {
  return props.categories && !Array.isArray(props.categories)
    ? props.categories[axis]
    : props.categories;
}
function getCategories(props, axis) {
  return props.categories && !Array.isArray(props.categories)
    ? props.categories[axis]
    : props.categories;
}
Returns an array of categories for a given axis
@param {Object} props: the props object
@param {String} axis: the current axis
@returns {Array} an array of categories