re-reselect/src/cache/FifoMapCache.js

Enhance Reselect selectors with deeper memoization and cache management

import validateCacheSize from './util/validateCacheSize';

export default class FifoMapCache {
  constructor({cacheSize} = {}) {
    validateCacheSize(cacheSize);
    this._cache = new Map();
    this._cacheSize = cacheSize;
  }
  set(key, selectorFn) {
    this._cache.set(key, selectorFn);

    if (this._cache.size > this._cacheSize) {
      const earliest = this._cache.keys().next().value;
      this.remove(earliest);
    }
  }
  get(key) {
    return this._cache.get(key);
  }
  remove(key) {
    this._cache.delete(key);
  }
  clear() {
    this._cache.clear();
  }
}