timers: support Symbol.dispose

PR-URL: nodejs#48633
Reviewed-By: Zeyu "Alex" Yang <[email protected]>
Reviewed-By: Benjamin Gruenbaum <[email protected]>
Reviewed-By: Robert Nagy <[email protected]>

Author: MoLow

doc/api/timers.md

@@ -63,6 +63,16 @@ loop to remain active. If there is no other activity keeping the event loop
 running, the process may exit before the `Immediate` object's callback is
 invoked. Calling `immediate.unref()` multiple times will have no effect.
 
+### `immediate[Symbol.dispose]()`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+> Stability: 1 - Experimental
+
+Cancels the immediate. This is similar to calling `clearImmediate()`.
+
 ## Class: `Timeout`
 
 This object is created internally and is returned from [`setTimeout()`][] and
@@ -157,6 +167,16 @@ across [`worker_threads`][] it must first be passed to the correct
 thread. This allows enhanced compatibility with browser
 `setTimeout()` and `setInterval()` implementations.
 
+### `timeout[Symbol.dispose]()`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+> Stability: 1 - Experimental
+
+Cancels the timeout.
+
 ## Scheduling timers
 
 A timer in Node.js is an internal construct that calls a given function after

lib/internal/per_context/primordials.js

@@ -228,7 +228,7 @@ function copyPrototype(src, dest, prefix) {
   copyPrototype(original.prototype, primordials, `${name}Prototype`);
 });
 
-// Define Symbol.Dispose and Symbol.AsyncDispose
+// Define Symbol.dispose and Symbol.asyncDispose
 // Until these are defined by the environment.
 // TODO(MoLow): Remove this polyfill once Symbol.dispose and Symbol.asyncDispose are available in V8.
 primordials.SymbolDispose ??= primordials.SymbolFor('nodejs.dispose');

lib/timers.js

@@ -24,6 +24,7 @@
 const {
   MathTrunc,
   ObjectDefineProperty,
+  SymbolDispose,
   SymbolToPrimitive,
 } = primordials;
 
@@ -253,6 +254,10 @@ Timeout.prototype.close = function() {
   return this;
 };
 
+Timeout.prototype[SymbolDispose] = function() {
+  clearTimeout(this);
+};
+
 /**
  * Coerces a `Timeout` to a primitive.
  * @returns {number}
@@ -338,6 +343,10 @@ function clearImmediate(immediate) {
   immediateQueue.remove(immediate);
 }
 
+Immediate.prototype[SymbolDispose] = function() {
+  clearImmediate(this);
+};
+
 module.exports = {
   setTimeout,
   clearTimeout,

test/parallel/test-timers-dispose.js

@@ -0,0 +1,18 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+
+const timer = setTimeout(common.mustNotCall(), 10);
+const interval = setInterval(common.mustNotCall(), 10);
+const immediate = setImmediate(common.mustNotCall());
+
+timer[Symbol.dispose]();
+interval[Symbol.dispose]();
+immediate[Symbol.dispose]();
+
+
+process.on('exit', () => {
+  assert.strictEqual(timer._destroyed, true);
+  assert.strictEqual(interval._destroyed, true);
+  assert.strictEqual(immediate._destroyed, true);
+});