challenge-algorithms-v2.0-s.../node_modules/jest-worker/build/Farm.js

153 lines
4.2 KiB
JavaScript

'use strict';
Object.defineProperty(exports, '__esModule', {
value: true
});
exports.default = void 0;
var _FifoQueue = _interopRequireDefault(require('./FifoQueue'));
var _types = require('./types');
function _interopRequireDefault(obj) {
return obj && obj.__esModule ? obj : {default: obj};
}
/**
* Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
class Farm {
_computeWorkerKey;
_workerSchedulingPolicy;
_cacheKeys = Object.create(null);
_locks = [];
_offset = 0;
_taskQueue;
constructor(_numOfWorkers, _callback, options = {}) {
this._numOfWorkers = _numOfWorkers;
this._callback = _callback;
this._computeWorkerKey = options.computeWorkerKey;
this._workerSchedulingPolicy =
options.workerSchedulingPolicy ?? 'round-robin';
this._taskQueue = options.taskQueue ?? new _FifoQueue.default();
}
doWork(method, ...args) {
const customMessageListeners = new Set();
const addCustomMessageListener = listener => {
customMessageListeners.add(listener);
return () => {
customMessageListeners.delete(listener);
};
};
const onCustomMessage = message => {
customMessageListeners.forEach(listener => listener(message));
};
const promise = new Promise(
// Bind args to this function so it won't reference to the parent scope.
// This prevents a memory leak in v8, because otherwise the function will
// retain args for the closure.
((args, resolve, reject) => {
const computeWorkerKey = this._computeWorkerKey;
const request = [_types.CHILD_MESSAGE_CALL, false, method, args];
let worker = null;
let hash = null;
if (computeWorkerKey) {
hash = computeWorkerKey.call(this, method, ...args);
worker = hash == null ? null : this._cacheKeys[hash];
}
const onStart = worker => {
if (hash != null) {
this._cacheKeys[hash] = worker;
}
};
const onEnd = (error, result) => {
customMessageListeners.clear();
if (error) {
reject(error);
} else {
resolve(result);
}
};
const task = {
onCustomMessage,
onEnd,
onStart,
request
};
if (worker) {
this._taskQueue.enqueue(task, worker.getWorkerId());
this._process(worker.getWorkerId());
} else {
this._push(task);
}
}).bind(null, args)
);
promise.UNSTABLE_onCustomMessage = addCustomMessageListener;
return promise;
}
_process(workerId) {
if (this._isLocked(workerId)) {
return this;
}
const task = this._taskQueue.dequeue(workerId);
if (!task) {
return this;
}
if (task.request[1]) {
throw new Error('Queue implementation returned processed task');
}
// Reference the task object outside so it won't be retained by onEnd,
// and other properties of the task object, such as task.request can be
// garbage collected.
let taskOnEnd = task.onEnd;
const onEnd = (error, result) => {
if (taskOnEnd) {
taskOnEnd(error, result);
}
taskOnEnd = null;
this._unlock(workerId);
this._process(workerId);
};
task.request[1] = true;
this._lock(workerId);
this._callback(
workerId,
task.request,
task.onStart,
onEnd,
task.onCustomMessage
);
return this;
}
_push(task) {
this._taskQueue.enqueue(task);
const offset = this._getNextWorkerOffset();
for (let i = 0; i < this._numOfWorkers; i++) {
this._process((offset + i) % this._numOfWorkers);
if (task.request[1]) {
break;
}
}
return this;
}
_getNextWorkerOffset() {
switch (this._workerSchedulingPolicy) {
case 'in-order':
return 0;
case 'round-robin':
return this._offset++;
}
}
_lock(workerId) {
this._locks[workerId] = true;
}
_unlock(workerId) {
this._locks[workerId] = false;
}
_isLocked(workerId) {
return this._locks[workerId];
}
}
exports.default = Farm;