process: move multipleResolves event to EOL

The `multipleResolves` event has been deprecated for several
years now. It's time.

Author: jasnell

doc/api/deprecations.md

@@ -3327,6 +3327,9 @@ the errors used for value type validation.
 
 <!-- YAML
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/00000
+    description: End-of-Life.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41896
     description: Runtime deprecation.
@@ -3337,10 +3340,10 @@ changes:
     description: Documentation-only deprecation.
 -->
 
-Type: Runtime
+Type: End-of-Life
 
-This event was deprecated because it did not work with V8 promise combinators
-which diminished its usefulness.
+This event was deprecated and remove because it did not work with V8 promise
+combinators which diminished its usefulness.
 
 ### DEP0161: `process._getActiveRequests()` and `process._getActiveHandles()`
 

doc/api/process.md

@@ -176,95 +176,6 @@ process, the `message` argument can contain data that JSON is not able
 to represent.
 See [Advanced serialization for `child_process`][] for more details.
 
-### Event: `'multipleResolves'`
-
-<!-- YAML
-added: v10.12.0
-deprecated:
-  - v17.6.0
-  - v16.15.0
--->
-
-> Stability: 0 - Deprecated
-
-* `type` {string} The resolution type. One of `'resolve'` or `'reject'`.
-* `promise` {Promise} The promise that resolved or rejected more than once.
-* `value` {any} The value with which the promise was either resolved or
-  rejected after the original resolve.
-
-The `'multipleResolves'` event is emitted whenever a `Promise` has been either:
-
-* Resolved more than once.
-* Rejected more than once.
-* Rejected after resolve.
-* Resolved after reject.
-
-This is useful for tracking potential errors in an application while using the
-`Promise` constructor, as multiple resolutions are silently swallowed. However,
-the occurrence of this event does not necessarily indicate an error. For
-example, [`Promise.race()`][] can trigger a `'multipleResolves'` event.
-
-Because of the unreliability of the event in cases like the
-[`Promise.race()`][] example above it has been deprecated.
-
-```mjs
-import process from 'node:process';
-
-process.on('multipleResolves', (type, promise, reason) => {
-  console.error(type, promise, reason);
-  setImmediate(() => process.exit(1));
-});
-
-async function main() {
-  try {
-    return await new Promise((resolve, reject) => {
-      resolve('First call');
-      resolve('Swallowed resolve');
-      reject(new Error('Swallowed reject'));
-    });
-  } catch {
-    throw new Error('Failed');
-  }
-}
-
-main().then(console.log);
-// resolve: Promise { 'First call' } 'Swallowed resolve'
-// reject: Promise { 'First call' } Error: Swallowed reject
-//     at Promise (*)
-//     at new Promise (<anonymous>)
-//     at main (*)
-// First call
-```
-
-```cjs
-const process = require('node:process');
-
-process.on('multipleResolves', (type, promise, reason) => {
-  console.error(type, promise, reason);
-  setImmediate(() => process.exit(1));
-});
-
-async function main() {
-  try {
-    return await new Promise((resolve, reject) => {
-      resolve('First call');
-      resolve('Swallowed resolve');
-      reject(new Error('Swallowed reject'));
-    });
-  } catch {
-    throw new Error('Failed');
-  }
-}
-
-main().then(console.log);
-// resolve: Promise { 'First call' } 'Swallowed resolve'
-// reject: Promise { 'First call' } Error: Swallowed reject
-//     at Promise (*)
-//     at new Promise (<anonymous>)
-//     at main (*)
-// First call
-```
-
 ### Event: `'rejectionHandled'`
 
 <!-- YAML
@@ -4603,7 +4514,6 @@ cases:
 [`Error`]: errors.md#class-error
 [`EventEmitter`]: events.md#class-eventemitter
 [`NODE_OPTIONS`]: cli.md#node_optionsoptions
-[`Promise.race()`]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/race
 [`Worker`]: worker_threads.md#class-worker
 [`Worker` constructor]: worker_threads.md#new-workerfilename-options
 [`console.error()`]: console.md#consoleerrordata-args

lib/internal/process/promises.js

@@ -43,27 +43,6 @@ const AsyncContextFrame = require('internal/async_context_frame');
 // *Must* match Environment::TickInfo::Fields in src/env.h.
 const kHasRejectionToWarn = 1;
 
-// By default true because in cases where process is not a global
-// it is not possible to determine if the user has added a listener
-// to the process object.
-let hasMultipleResolvesListener = true;
-
-if (process.on) {
-  hasMultipleResolvesListener = process.listenerCount('multipleResolves') !== 0;
-
-  process.on('newListener', (eventName) => {
-    if (eventName === 'multipleResolves') {
-      hasMultipleResolvesListener = true;
-    }
-  });
-
-  process.on('removeListener', (eventName) => {
-    if (eventName === 'multipleResolves') {
-      hasMultipleResolvesListener = process.listenerCount('multipleResolves') !== 0;
-    }
-  });
-}
-
 /**
  * Errors & Warnings
  */
@@ -192,55 +171,16 @@ function promiseRejectHandler(type, promise, reason) {
       handledRejection(promise);
       break;
     case kPromiseRejectAfterResolved: // 2
-      if (hasMultipleResolvesListener) {
-        resolveErrorReject(promise, reason);
-      }
+      // Do nothing in this case. Previous we would emit a multipleResolves
+      // event but that was deprecated then later removed.
       break;
     case kPromiseResolveAfterResolved: // 3
-      if (hasMultipleResolvesListener) {
-        resolveErrorResolve(promise, reason);
-      }
+      // Do nothing in this case. Previous we would emit a multipleResolves
+      // event but that was deprecated then later removed.
       break;
   }
 }
 
-const multipleResolvesDeprecate = deprecate(
-  () => {},
-  'The multipleResolves event has been deprecated.',
-  'DEP0160',
-);
-
-/**
- * @param {Promise} promise
- * @param {Error} reason
- */
-function resolveErrorResolve(promise, reason) {
-  // We have to wrap this in a next tick. Otherwise the error could be caught by
-  // the executed promise.
-  process.nextTick(() => {
-    // Emit the multipleResolves event.
-    // This is a deprecated event, so we have to check if it's being listened to.
-    if (process.emit('multipleResolves', 'resolve', promise, reason)) {
-      // If the event is being listened to, emit a deprecation warning.
-      multipleResolvesDeprecate();
-    }
-  });
-}
-
-/**
- * @param {Promise} promise
- * @param {Error} reason
- */
-function resolveErrorReject(promise, reason) {
-  // We have to wrap this in a next tick. Otherwise the error could be caught by
-  // the executed promise.
-  process.nextTick(() => {
-    if (process.emit('multipleResolves', 'reject', promise, reason)) {
-      multipleResolvesDeprecate();
-    }
-  });
-}
-
 /**
  * @param {Promise} promise
  * @param {PromiseInfo} promiseInfo

test/parallel/test-events-once.js

@@ -105,7 +105,6 @@ async function stopListeningAfterCatchingError() {
   } catch (_e) {
     err = _e;
   }
-  process.removeAllListeners('multipleResolves');
   strictEqual(err, expected);
   strictEqual(ee.listenerCount('error'), 0);
   strictEqual(ee.listenerCount('myevent'), 0);

test/parallel/test-promise-swallowed-event.js

@@ -10,8 +10,6 @@ const rejectPromise = new Promise((r) => setTimeout(r, 10, rejection2));
 const swallowedResolve = 'Swallowed resolve';
 const swallowedResolve2 = 'Foobar';
 
-process.on('multipleResolves', common.mustCall(handler, 4));
-
 const p1 = new Promise((resolve, reject) => {
   resolve(resolveMessage);
   resolve(swallowedResolve);

test/parallel/test-timers-immediate-promisified.js

@@ -14,8 +14,6 @@ const setPromiseImmediate = promisify(timers.setImmediate);
 
 assert.strictEqual(setPromiseImmediate, timerPromises.setImmediate);
 
-process.on('multipleResolves', common.mustNotCall());
-
 {
   const promise = setPromiseImmediate();
   promise.then(common.mustCall((value) => {

test/parallel/test-timers-interval-promisified.js

@@ -14,8 +14,6 @@ const setPromiseTimeout = promisify(timers.setTimeout);
 
 const { setInterval } = timerPromises;
 
-process.on('multipleResolves', common.mustNotCall());
-
 {
   const iterable = setInterval(1, undefined);
   const iterator = iterable[Symbol.asyncIterator]();

test/parallel/test-timers-timeout-promisified.js

@@ -14,8 +14,6 @@ const setPromiseTimeout = promisify(timers.setTimeout);
 
 assert.strictEqual(setPromiseTimeout, timerPromises.setTimeout);
 
-process.on('multipleResolves', common.mustNotCall());
-
 {
   const promise = setPromiseTimeout(1);
   promise.then(common.mustCall((value) => {