From ffd2a62c3f7df94365980302fef3bc3376b48182 Mon Sep 17 00:00:00 2001 From: Florian Dold Date: Mon, 3 Aug 2020 13:00:48 +0530 Subject: modularize repo, use pnpm, improve typechecking --- .../taler-wallet-core/src/util/promiseUtils.ts | 60 ++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 packages/taler-wallet-core/src/util/promiseUtils.ts (limited to 'packages/taler-wallet-core/src/util/promiseUtils.ts') diff --git a/packages/taler-wallet-core/src/util/promiseUtils.ts b/packages/taler-wallet-core/src/util/promiseUtils.ts new file mode 100644 index 000000000..d409686d9 --- /dev/null +++ b/packages/taler-wallet-core/src/util/promiseUtils.ts @@ -0,0 +1,60 @@ +/* + This file is part of GNU Taler + (C) 2019 GNUnet e.V. + + TALER is free software; you can redistribute it and/or modify it under the + terms of the GNU General Public License as published by the Free Software + Foundation; either version 3, or (at your option) any later version. + + TALER is distributed in the hope that it will be useful, but WITHOUT ANY + WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR + A PARTICULAR PURPOSE. See the GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along with + TALER; see the file COPYING. If not, see + */ + +export interface OpenedPromise { + promise: Promise; + resolve: (val: T) => void; + reject: (err: any) => void; +} + +/** + * Get an unresolved promise together with its extracted resolve / reject + * function. + */ +export function openPromise(): OpenedPromise { + let resolve: ((x?: any) => void) | null = null; + let reject: ((reason?: any) => void) | null = null; + const promise = new Promise((res, rej) => { + resolve = res; + reject = rej; + }); + if (!(resolve && reject)) { + // Never happens, unless JS implementation is broken + throw Error(); + } + return { resolve, reject, promise }; +} + +export class AsyncCondition { + private _waitPromise: Promise; + private _resolveWaitPromise: (val: void) => void; + constructor() { + const op = openPromise(); + this._waitPromise = op.promise; + this._resolveWaitPromise = op.resolve; + } + + wait(): Promise { + return this._waitPromise; + } + + trigger(): void { + this._resolveWaitPromise(); + const op = openPromise(); + this._waitPromise = op.promise; + this._resolveWaitPromise = op.resolve; + } +} -- cgit v1.2.3