packager: AsyncTaskGroup: @flow

Reviewed By: cpojer

Differential Revision: D5137195

fbshipit-source-id: 7d61d8f920ea5db7f70415e9f8fb7749a279bec8
This commit is contained in:
Jean Lauliac 2017-05-30 04:48:26 -07:00 committed by Facebook Github Bot
parent 414da08a80
commit dfb081282f
1 changed files with 11 additions and 3 deletions

View File

@ -5,23 +5,31 @@
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @flow
*/
'use strict';
module.exports = class AsyncTaskGroup {
module.exports = class AsyncTaskGroup<TTaskHandle> {
_runningTasks: Set<TTaskHandle>;
_resolve: ?() => void;
done: Promise<void>;
constructor() {
this._runningTasks = new Set();
this._resolve = null;
this.done = new Promise(resolve => this._resolve = resolve);
}
start(taskHandle) {
start(taskHandle: TTaskHandle) {
this._runningTasks.add(taskHandle);
}
end(taskHandle) {
end(taskHandle: TTaskHandle) {
const runningTasks = this._runningTasks;
if (runningTasks.delete(taskHandle) && runningTasks.size === 0) {
/* $FlowFixMe: could be null */
this._resolve();
}
}