diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
commit | 26a029d407be480d791972afb5975cf62c9360a6 (patch) | |
tree | f435a8308119effd964b339f76abb83a57c29483 /devtools/shared/ThreadSafeDevToolsUtils.js | |
parent | Initial commit. (diff) | |
download | firefox-upstream/124.0.1.tar.xz firefox-upstream/124.0.1.zip |
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'devtools/shared/ThreadSafeDevToolsUtils.js')
-rw-r--r-- | devtools/shared/ThreadSafeDevToolsUtils.js | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/devtools/shared/ThreadSafeDevToolsUtils.js b/devtools/shared/ThreadSafeDevToolsUtils.js new file mode 100644 index 0000000000..fba93a9dcc --- /dev/null +++ b/devtools/shared/ThreadSafeDevToolsUtils.js @@ -0,0 +1,363 @@ +/* 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"; + +/** + * General utilities used throughout devtools that can also be used in + * workers. + */ + +/** + * Immutably reduce the given `...objs` into one object. The reduction is + * applied from left to right, so `immutableUpdate({ a: 1 }, { a: 2 })` will + * result in `{ a: 2 }`. The resulting object is frozen. + * + * Example usage: + * + * const original = { foo: 1, bar: 2, baz: 3 }; + * const modified = immutableUpdate(original, { baz: 0, bang: 4 }); + * + * // We get the new object that we expect... + * assert(modified.baz === 0); + * assert(modified.bang === 4); + * + * // However, the original is not modified. + * assert(original.baz === 2); + * assert(original.bang === undefined); + * + * @param {...Object} ...objs + * @returns {Object} + */ +exports.immutableUpdate = function (...objs) { + return Object.freeze(Object.assign({}, ...objs)); +}; + +/** + * Utility function for updating an object with the properties of + * other objects. + * + * DEPRECATED: Just use Object.assign() instead! + * + * @param aTarget Object + * The object being updated. + * @param aNewAttrs Object + * The rest params are objects to update aTarget with. You + * can pass as many as you like. + */ +exports.update = function update(target, ...args) { + for (const attrs of args) { + for (const key in attrs) { + const desc = Object.getOwnPropertyDescriptor(attrs, key); + + if (desc) { + Object.defineProperty(target, key, desc); + } + } + } + return target; +}; + +/** + * Utility function for getting the values from an object as an array + * + * @param object Object + * The object to iterate over + */ +exports.values = function values(object) { + return Object.keys(object).map(k => object[k]); +}; + +/** + * Report that |who| threw an exception, |exception|. + */ +exports.reportException = function reportException(who, exception) { + const msg = `${who} threw an exception: ${exports.safeErrorString( + exception + )}`; + dump(msg + "\n"); + + if (typeof console !== "undefined" && console && console.error) { + console.error(exception); + } +}; + +/** + * Given a handler function that may throw, return an infallible handler + * function that calls the fallible handler, and logs any exceptions it + * throws. + * + * @param handler function + * A handler function, which may throw. + * @param aName string + * A name for handler, for use in error messages. If omitted, we use + * handler.name. + * + * (SpiderMonkey does generate good names for anonymous functions, but we + * don't have a way to get at them from JavaScript at the moment.) + */ +exports.makeInfallible = function (handler, name = handler.name) { + return function () { + try { + return handler.apply(this, arguments); + } catch (ex) { + let who = "Handler function"; + if (name) { + who += " " + name; + } + exports.reportException(who, ex); + return undefined; + } + }; +}; + +/** + * Turn the |error| into a string, without fail. + * + * @param {Error|any} error + */ +exports.safeErrorString = function (error) { + try { + let errorString = error.toString(); + if (typeof errorString == "string") { + // Attempt to attach a stack to |errorString|. If it throws an error, or + // isn't a string, don't use it. + try { + if (error.stack) { + const stack = error.stack.toString(); + if (typeof stack == "string") { + errorString += "\nStack: " + stack; + } + } + } catch (ee) { + // Ignore. + } + + // Append additional line and column number information to the output, + // since it might not be part of the stringified error. + if ( + typeof error.lineNumber == "number" && + typeof error.columnNumber == "number" + ) { + errorString += + "Line: " + error.lineNumber + ", column: " + error.columnNumber; + } + + return errorString; + } + } catch (ee) { + // Ignore. + } + + // We failed to find a good error description, so do the next best thing. + return Object.prototype.toString.call(error); +}; + +/** + * Interleaves two arrays element by element, returning the combined array, like + * a zip. In the case of arrays with different sizes, undefined values will be + * interleaved at the end along with the extra values of the larger array. + * + * @param Array a + * @param Array b + * @returns Array + * The combined array, in the form [a1, b1, a2, b2, ...] + */ +exports.zip = function (a, b) { + if (!b) { + return a; + } + if (!a) { + return b; + } + const pairs = []; + for ( + let i = 0, aLength = a.length, bLength = b.length; + i < aLength || i < bLength; + i++ + ) { + pairs.push([a[i], b[i]]); + } + return pairs; +}; + +/** + * Converts an object into an array with 2-element arrays as key/value + * pairs of the object. `{ foo: 1, bar: 2}` would become + * `[[foo, 1], [bar 2]]` (order not guaranteed). + * + * @param object obj + * @returns array + */ +exports.entries = function entries(obj) { + return Object.keys(obj).map(k => [k, obj[k]]); +}; + +/* + * Takes an array of 2-element arrays as key/values pairs and + * constructs an object using them. + */ +exports.toObject = function (arr) { + const obj = {}; + for (const [k, v] of arr) { + obj[k] = v; + } + return obj; +}; + +/** + * Composes the given functions into a single function, which will + * apply the results of each function right-to-left, starting with + * applying the given arguments to the right-most function. + * `compose(foo, bar, baz)` === `args => foo(bar(baz(args)))` + * + * @param ...function funcs + * @returns function + */ +exports.compose = function compose(...funcs) { + return (...args) => { + const initialValue = funcs[funcs.length - 1](...args); + const leftFuncs = funcs.slice(0, -1); + return leftFuncs.reduceRight((composed, f) => f(composed), initialValue); + }; +}; + +/** + * Return true if `thing` is a generator function, false otherwise. + */ +exports.isGenerator = function (fn) { + if (typeof fn !== "function") { + return false; + } + const proto = Object.getPrototypeOf(fn); + if (!proto) { + return false; + } + const ctor = proto.constructor; + if (!ctor) { + return false; + } + return ctor.name == "GeneratorFunction"; +}; + +/** + * Return true if `thing` is an async function, false otherwise. + */ +exports.isAsyncFunction = function (fn) { + if (typeof fn !== "function") { + return false; + } + const proto = Object.getPrototypeOf(fn); + if (!proto) { + return false; + } + const ctor = proto.constructor; + if (!ctor) { + return false; + } + return ctor.name == "AsyncFunction"; +}; + +/** + * Return true if `thing` is a Promise or then-able, false otherwise. + */ +exports.isPromise = function (p) { + return p && typeof p.then === "function"; +}; + +/** + * Return true if `thing` is a SavedFrame, false otherwise. + */ +exports.isSavedFrame = function (thing) { + return Object.prototype.toString.call(thing) === "[object SavedFrame]"; +}; + +/** + * Return true iff `thing` is a `Set` object (possibly from another global). + */ +exports.isSet = function (thing) { + return Object.prototype.toString.call(thing) === "[object Set]"; +}; + +/** + * Given a list of lists, flatten it. Only flattens one level; does not + * recursively flatten all levels. + * + * @param {Array<Array<Any>>} lists + * @return {Array<Any>} + */ +exports.flatten = function (lists) { + return Array.prototype.concat.apply([], lists); +}; + +/** + * Returns a promise that is resolved or rejected when all promises have settled + * (resolved or rejected). + * + * This differs from Promise.all, which will reject immediately after the first + * rejection, instead of waiting for the remaining promises to settle. + * + * @param values + * Iterable of promises that may be pending, resolved, or rejected. When + * when all promises have settled (resolved or rejected), the returned + * promise will be resolved or rejected as well. + * + * @return A new promise that is fulfilled when all values have settled + * (resolved or rejected). Its resolution value will be an array of all + * resolved values in the given order, or undefined if values is an + * empty array. The reject reason will be forwarded from the first + * promise in the list of given promises to be rejected. + */ +exports.settleAll = values => { + if (values === null || typeof values[Symbol.iterator] != "function") { + throw new Error("settleAll() expects an iterable."); + } + + return new Promise((resolve, reject) => { + values = Array.isArray(values) ? values : [...values]; + let countdown = values.length; + const resolutionValues = new Array(countdown); + let rejectionValue; + let rejectionOccurred = false; + + if (!countdown) { + resolve(resolutionValues); + return; + } + + function checkForCompletion() { + if (--countdown > 0) { + return; + } + if (!rejectionOccurred) { + resolve(resolutionValues); + } else { + reject(rejectionValue); + } + } + + for (let i = 0; i < values.length; i++) { + const index = i; + const value = values[i]; + const resolver = result => { + resolutionValues[index] = result; + checkForCompletion(); + }; + const rejecter = error => { + if (!rejectionOccurred) { + rejectionValue = error; + rejectionOccurred = true; + } + checkForCompletion(); + }; + + if (value && typeof value.then == "function") { + value.then(resolver, rejecter); + } else { + // Given value is not a promise, forward it as a resolution value. + resolver(value); + } + } + }); +}; |