recoil/cjs/caches/__tests__/Recoil_TreeCache-test.js.flow

Recoil - A state management library for React

/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @emails oncall+recoil
 * @flow strict-local
 * @format
 */
'use strict';

const {
  getRecoilTestFn
} = require('../../__test_utils__/Recoil_TestingUtils');

let TreeCache, loadableWithValue, nullthrows;
const testRecoil = getRecoilTestFn(() => {
  ({
    TreeCache
  } = require('../Recoil_TreeCache'));
  nullthrows = require('../../util/Recoil_nullthrows');
  ({
    loadableWithValue
  } = require('../../adt/Recoil_Loadable'));
});
describe('TreeCache', () => {
  testRecoil('setting and getting values', () => {
    const cache = new TreeCache();
    const [route1, loadable1] = [[['a', 2], ['b', 3]], loadableWithValue('value1')];
    const [route2, loadable2] = [[['a', 3], ['b', 4]], loadableWithValue('value2')];
    const [route3, loadable3] = [[['a', 4]], loadableWithValue('value3')];
    cache.set(route1, loadable1);
    cache.set(route2, loadable2);
    cache.set(route3, loadable3);
    expect(cache.get(nodeKey => route1.find(([key]) => key === nodeKey)?.[1])).toBe(loadable1);
    expect(cache.get(nodeKey => route2.find(([key]) => key === nodeKey)?.[1])).toBe(loadable2);
    expect(cache.get(nodeKey => route3.find(([key]) => key === nodeKey)?.[1])).toBe(loadable3);
    expect(cache.size()).toBe(3);
  });
  testRecoil('deleting values', () => {
    const cache = new TreeCache();
    const [route1, loadable1] = [[['a', 2], ['b', 3]], loadableWithValue('value1')];
    const [route2, loadable2] = [[['a', 3], ['b', 4]], loadableWithValue('value2')];
    const [route3, loadable3] = [[['a', 4]], loadableWithValue('value3')];
    cache.set(route1, loadable1);
    cache.set(route2, loadable2);
    cache.set(route3, loadable3);
    const leaf1 = cache.getLeafNode(nodeKey => route1.find(([key]) => key === nodeKey)?.[1]);
    const leaf2 = cache.getLeafNode(nodeKey => route2.find(([key]) => key === nodeKey)?.[1]);
    const leaf3 = cache.getLeafNode(nodeKey => route3.find(([key]) => key === nodeKey)?.[1]);
    expect(leaf1).toBeDefined();
    expect(leaf2).toBeDefined();
    expect(leaf3).toBeDefined();
    const leaf1Node = nullthrows(leaf1);
    const leaf2Node = nullthrows(leaf2);
    const leaf3Node = nullthrows(leaf3);
    expect(cache.size()).toBe(3);
    const deleted1 = cache.delete(leaf1Node);
    expect(deleted1).toBe(true);
    expect(cache.size()).toBe(2);
    const deleted2 = cache.delete(leaf2Node);
    expect(deleted2).toBe(true);
    expect(cache.size()).toBe(1);
    const deleted3 = cache.delete(leaf3Node);
    expect(deleted3).toBe(true);
    expect(cache.size()).toBe(0);
    expect(cache.root()).toBeNull();
    const deletedAgain = cache.delete(leaf1Node);
    expect(deletedAgain).toBe(false);
  });
  testRecoil('onHit() handler', () => {
    const [route1, loadable1] = [[['a', 2], ['b', 3]], loadableWithValue('value1')];
    const onHit = jest.fn();
    const cache = new TreeCache({
      onHit
    });
    declare var getter: (nodeKey: any) => any;
    cache.set(route1, loadable1); // hit

    cache.get(getter); // miss

    cache.get(() => {}); // hit

    cache.get(getter);
    expect(onHit).toHaveBeenCalledTimes(2);
  });
  testRecoil('onSet() handler', () => {
    const onSet = jest.fn();
    const cache = new TreeCache({
      onSet
    });
    const [route1, loadable1] = [[['a', 2], ['b', 3]], loadableWithValue('value1')];
    const [route2, loadable2] = [[['a', 3], ['b', 4]], loadableWithValue('value2')];
    const [route3, loadable3] = [[['a', 4]], loadableWithValue('value3')];
    cache.set(route1, loadable1);
    cache.set(route2, loadable2);
    cache.set(route3, loadable3);
    expect(onSet).toHaveBeenCalledTimes(3);
  });
  testRecoil('default key generation uses reference equality', () => {
    const [route1, loadable1] = [[['a', [2]], ['b', [3]]], loadableWithValue('value1')];
    const cache = new TreeCache();
    cache.set(route1, loadable1);
    const resultWithKeyCopy = cache.get(nodeKey => [...(route1.find(([key]) => key === nodeKey)?.[1] ?? [])]);
    expect(resultWithKeyCopy).toBeUndefined();
    const result = cache.get(nodeKey => route1.find(([key]) => key === nodeKey)?.[1]);
    expect(result).toBe(loadable1);
  });
  testRecoil('mapNodeValue() to implement value equality keys', () => {
    const cache = new TreeCache({
      mapNodeValue: value => JSON.stringify(value)
    });
    const [route1, loadable1] = [[['a', [2]], ['b', [3]]], loadableWithValue('value1')];
    cache.set(route1, loadable1);
    const resultWithKeyCopy = cache.get(nodeKey => [...(route1.find(([key]) => key === nodeKey)?.[1] ?? [])]);
    expect(resultWithKeyCopy).toBe(loadable1);
  });
});