| var global = require('../internals/global'); |
| var getOwnPropertyDescriptor = require('../internals/object-get-own-property-descriptor').f; |
| var classof = require('../internals/classof-raw'); |
| var macrotask = require('../internals/task').set; |
| var userAgent = require('../internals/user-agent'); |
| |
| var MutationObserver = global.MutationObserver || global.WebKitMutationObserver; |
| var process = global.process; |
| var Promise = global.Promise; |
| var IS_NODE = classof(process) == 'process'; |
| // Node.js 11 shows ExperimentalWarning on getting `queueMicrotask` |
| var queueMicrotaskDescriptor = getOwnPropertyDescriptor(global, 'queueMicrotask'); |
| var queueMicrotask = queueMicrotaskDescriptor && queueMicrotaskDescriptor.value; |
| |
| var flush, head, last, notify, toggle, node, promise, then; |
| |
| // modern engines have queueMicrotask method |
| if (!queueMicrotask) { |
| flush = function () { |
| var parent, fn; |
| if (IS_NODE && (parent = process.domain)) parent.exit(); |
| while (head) { |
| fn = head.fn; |
| head = head.next; |
| try { |
| fn(); |
| } catch (error) { |
| if (head) notify(); |
| else last = undefined; |
| throw error; |
| } |
| } last = undefined; |
| if (parent) parent.enter(); |
| }; |
| |
| // Node.js |
| if (IS_NODE) { |
| notify = function () { |
| process.nextTick(flush); |
| }; |
| // browsers with MutationObserver, except iOS - https://github.com/zloirock/core-js/issues/339 |
| } else if (MutationObserver && !/(iphone|ipod|ipad).*applewebkit/i.test(userAgent)) { |
| toggle = true; |
| node = document.createTextNode(''); |
| new MutationObserver(flush).observe(node, { characterData: true }); |
| notify = function () { |
| node.data = toggle = !toggle; |
| }; |
| // environments with maybe non-completely correct, but existent Promise |
| } else if (Promise && Promise.resolve) { |
| // Promise.resolve without an argument throws an error in LG WebOS 2 |
| promise = Promise.resolve(undefined); |
| then = promise.then; |
| notify = function () { |
| then.call(promise, flush); |
| }; |
| // for other environments - macrotask based on: |
| // - setImmediate |
| // - MessageChannel |
| // - window.postMessag |
| // - onreadystatechange |
| // - setTimeout |
| } else { |
| notify = function () { |
| // strange IE + webpack dev server bug - use .call(global) |
| macrotask.call(global, flush); |
| }; |
| } |
| } |
| |
| module.exports = queueMicrotask || function (fn) { |
| var task = { fn: fn, next: undefined }; |
| if (last) last.next = task; |
| if (!head) { |
| head = task; |
| notify(); |
| } last = task; |
| }; |