versionActionCreator.js

//
import semver from 'semver';

//
export function createAction(type) {
  const versions = [];
  const map = {};

  //
  function actionCreator(userRange) {
    const range = semver.validRange(userRange);

    if (range === null) {
      throw new Error(`"${userRange}" is not a valid semantic version range"`);
    }

    const version = semver.maxSatisfying(versions, range);

    if (version === null) {
      throw new Error(`no action creator was found for "${range}""`);
    }

    return map[version];
  }

  //
  actionCreator.addVersion = (userVersion, fn) => {
    const version = semver.valid(userVersion);

    if (version === null) {
      throw new Error(`"${userVersion}" is not a valid semantic version"`);
    }

    if (versions.indexOf(version) !== -1) {
      throw new Error(`an action creator with version "${version}" already exists"`);
    }

    //
    function versionedActionCreator(...args) {
      const action = fn(...args);

      //
      return {
        type,
        ...action,
        meta: {
          ...action.meta,
          version,
        },
      };
    }

    //
    versions.push(version);
    map[version] = versionedActionCreator;

    //
    return actionCreator;
  };

  //
  return actionCreator;
}

//
export default createAction;