How to use getExposedMethods method in Jest

Best JavaScript code snippet using jest

index.js

Source:index.js

...27    obj[key] = value;28  }29  return obj;30}31function getExposedMethods(workerPath, options) {32  let exposedMethods = options.exposedMethods; // If no methods list is given, try getting it by auto-requiring the module.33  if (!exposedMethods) {34    const module = require(workerPath);35    exposedMethods = Object.keys(module).filter(36      // @ts-ignore: no index37      name => typeof module[name] === 'function'38    );39    if (typeof module === 'function') {40      exposedMethods = [...exposedMethods, 'default'];41    }42  }43  return exposedMethods;44}45/**46 * The Jest farm (publicly called "Worker") is a class that allows you to queue47 * methods across multiple child processes, in order to parallelize work. This48 * is done by providing an absolute path to a module that will be loaded on each49 * of the child processes, and bridged to the main process.50 *51 * Bridged methods are specified by using the "exposedMethods" property of the52 * "options" object. This is an array of strings, where each of them corresponds53 * to the exported name in the loaded module.54 *55 * You can also control the amount of workers by using the "numWorkers" property56 * of the "options" object, and the settings passed to fork the process through57 * the "forkOptions" property. The amount of workers defaults to the amount of58 * CPUS minus one.59 *60 * Queueing calls can be done in two ways:61 *   - Standard method: calls will be redirected to the first available worker,62 *     so they will get executed as soon as they can.63 *64 *   - Sticky method: if a "computeWorkerKey" method is provided within the65 *     config, the resulting string of this method will be used as a key.66 *     Every time this key is returned, it is guaranteed that your job will be67 *     processed by the same worker. This is specially useful if your workers68 *     are caching results.69 */70class JestWorker {71  constructor(workerPath, options) {72    _defineProperty(this, '_ending', void 0);73    _defineProperty(this, '_farm', void 0);74    _defineProperty(this, '_options', void 0);75    _defineProperty(this, '_workerPool', void 0);76    this._options = {...options};77    this._ending = false;78    const workerPoolOptions = {79      enableWorkerThreads: this._options.enableWorkerThreads || false,80      forkOptions: this._options.forkOptions || {},81      maxRetries: this._options.maxRetries || 3,82      numWorkers:83        this._options.numWorkers || Math.max((0, _os().cpus)().length - 1, 1),84      setupArgs: this._options.setupArgs || []85    };86    if (this._options.WorkerPool) {87      // @ts-ignore: constructor target any?88      this._workerPool = new this._options.WorkerPool(89        workerPath,90        workerPoolOptions91      );92    } else {93      this._workerPool = new _WorkerPool.default(workerPath, workerPoolOptions);94    }95    this._farm = new _Farm.default(96      workerPoolOptions.numWorkers,97      this._workerPool.send.bind(this._workerPool),98      this._options.computeWorkerKey99    );100    this._bindExposedWorkerMethods(workerPath, this._options);101  }102  _bindExposedWorkerMethods(workerPath, options) {103    getExposedMethods(workerPath, options).forEach(name => {104      if (name.startsWith('_')) {105        return;106      }107      if (this.constructor.prototype.hasOwnProperty(name)) {108        throw new TypeError('Cannot define a method called ' + name);109      } // @ts-ignore: dynamic extension of the class instance is expected.110      this[name] = this._callFunctionWithArgs.bind(this, name);111    });112  }113  _callFunctionWithArgs(method, ...args) {114    if (this._ending) {115      throw new Error('Farm is ended, no more calls can be done to it');116    }117    return this._farm.doWork(method, ...args);...

satan.mocha.js

Source:satan.mocha.js

...34    Satan.should.have.property('killDaemon');35  });36  describe('DAEMON', function() {37    it.skip('should have the right exposed methods via RPC', function(done) {38      Satan.getExposedMethods(function(err, methods) {39        assert(err == null);40        methods.should.have.property('prepare');41        methods.should.have.property('getMonitorData');42        methods.should.have.property('getSystemData');43        methods.should.have.property('stopProcessId');44        methods.should.have.property('stopAll');45        methods.should.have.property('stopProcessName');46        methods.should.have.property('killMe');47        done();48      });49    });50    it('should get an empty process list', function(done) {51      Satan.executeRemote('getMonitorData', {}, function(err, res) {52        assert(res.length === 0);...

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