@homer0/prettier-plugin-jsdoc/src/fns/formatTSTypes.js

A Prettier plugin to format JSDoc blocks

const R = require('ramda');
const { capitalize, ensureArray } = require('./utils');
const { get, provider } = require('./app');

/**
 * Utility function generated by {@link getFormatter} and that can be used to modify a
 * type name. The difference between the formatter and the modifier is that the formatter
 * can extract single types from a complex type and run them through the modifier, where
 * the modifier can only handle one type.
 *
 * @callback TypeFormatter
 * @param {string} type  The original type.
 * @returns {string}
 */

/**
 * Utility function that is sent to {@link getFormatter} and that the formatter will use
 * to modify each single type name referenced on the given type.
 *
 * @callback TypeModifier
 * @param {string} type  The original type.
 * @returns {string}
 */

/**
 * Generates a formatter function that will replace a type (or types) after sending it
 * through a modification function.
 *
 * @param {string | string[]} type      The type or types to format.
 * @param {TypeModifier}      modifier  The function that will modify each type.
 * @returns {TypeFormatter}
 */
const getFormatter = (type, modifier) =>
  R.compose(
    (types) =>
      R.replace(
        new RegExp(`([^\\w]|^)(${types})([^\\w]|$)`, 'g'),
        (_, before, rawType, after) => `${before}${modifier(rawType)}${after}`,
      ),
    R.join('|'),
    get(ensureArray),
  )(type);

/**
 * Formats each type reference on a type in order to match the casing allowed by
 * TypeScript.
 *
 * @param {string} type  The type to format.
 * @returns {string}
 */
const formatTSTypes = (type) => {
  const useGetFormatter = get(getFormatter);
  return R.compose(
    useGetFormatter(['array', 'object'], get(capitalize)),
    useGetFormatter(['String', 'Number', 'Boolean'], R.toLower),
  )(type);
};

module.exports.formatTSTypes = formatTSTypes;
module.exports.getFormatter = getFormatter;
module.exports.provider = provider('formatTSTypes', module.exports);