From 6bf0a5cb5034a7e684dcc3500e841785237ce2dd Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 19:32:43 +0200 Subject: Adding upstream version 1:115.7.0. Signed-off-by: Daniel Baumann --- devtools/shared/async-utils.js | 71 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 71 insertions(+) create mode 100644 devtools/shared/async-utils.js (limited to 'devtools/shared/async-utils.js') diff --git a/devtools/shared/async-utils.js b/devtools/shared/async-utils.js new file mode 100644 index 0000000000..cb1fee1a4f --- /dev/null +++ b/devtools/shared/async-utils.js @@ -0,0 +1,71 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +"use strict"; + +/** + * Helpers for async functions. An async function returns a Promise for the + * resolution of the function. When the function returns, the promise is + * resolved with the returned value. If it throws the promise rejects with + * the thrown error. + */ + +/** + * Adds an event listener to the given element, and then removes its event + * listener once the event is called, returning the event object as a promise. + * @param Element element + * The DOM element to listen on + * @param String event + * The name of the event type to listen for + * @param Boolean useCapture + * Should we initiate the capture phase? + * @return Promise + * The promise resolved with the event object when the event first + * happens + */ +exports.listenOnce = function listenOnce(element, event, useCapture) { + return new Promise(function (resolve, reject) { + const onEvent = function (ev) { + element.removeEventListener(event, onEvent, useCapture); + resolve(ev); + }; + element.addEventListener(event, onEvent, useCapture); + }); +}; + +// Return value when `safeAsyncMethod` catches an error. +const SWALLOWED_RET = Symbol("swallowed"); + +/** + * Wraps the provided async method in a try/catch block. + * If an error is caught while running the method, check the provided condition + * to decide whether the error should bubble or not. + * + * @param {Function} asyncFn + * The async method to wrap. + * @param {Function} shouldSwallow + * Function that will run when an error is caught. If it returns true, + * the error will be swallowed. Otherwise, it will bubble up. + * @param {Mixed} retValue + * Optional value to return when an error is caught and is swallowed. + * @return {Function} The wrapped method. + */ +exports.safeAsyncMethod = function ( + asyncFn, + shouldSwallow, + retValue = SWALLOWED_RET +) { + return async function (...args) { + try { + const ret = await asyncFn(...args); + return ret; + } catch (e) { + if (shouldSwallow()) { + console.warn("Async method failed in safeAsyncMethod", e); + return retValue; + } + throw e; + } + }; +}; -- cgit v1.2.3