doc: document missing options of events.on

doc/api/events.md

@@ -1661,12 +1661,31 @@
 added:
  - v13.6.0
  - v12.16.0
+changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/52080
+    description: Support `highWaterMark` and `lowWaterMark` options,
+                 For consistency. Old options are still supported.
+  - version:
+    - v20.0.0
+    pr-url: https://github.com/nodejs/node/pull/41276
+    description: The `close`, `highWatermark`, and `lowWatermark`
+                 options are supported now.
 -->
 
 * `emitter` {EventEmitter}
 * `eventName` {string|symbol} The name of the event being listened for
 * `options` {Object}
   * `signal` {AbortSignal} Can be used to cancel awaiting events.
+  * `close` - {string\[]} Names of events that will end the iteration.
+  * `highWaterMark` - {integer} **Default:** `Number.MAX_SAFE_INTEGER`
+    The high watermark. The emitter is paused every time the size of events
+    being buffered is higher than it. Supported only on emitters implementing
+    `pause()` and `resume()` methods.
+  * `lowWaterMark` - {integer} **Default:** `1`
+    The low watermark. The emitter is resumed every time the size of events
+    being buffered is lower than it. Supported only on emitters implementing
+    `pause()` and `resume()` methods.
 * Returns: {AsyncIterator} that iterates `eventName` events emitted by the `emitter`
 
 ```mjs

lib/events.js

@@ -1053,8 +1053,8 @@ function eventTargetAgnosticAddListener(emitter, name, listener, flags) {
  * @param {{
  *    signal: AbortSignal;
  *    close?: string[];
- *    highWatermark?: number,
- *    lowWatermark?: number
+ *    highWaterMark?: number,
+ *    lowWaterMark?: number
  *   }} [options]
  * @returns {AsyncIterator}
  */
@@ -1065,10 +1065,12 @@ function on(emitter, event, options = kEmptyObject) {
   validateAbortSignal(signal, 'options.signal');
   if (signal?.aborted)
     throw new AbortError(undefined, { cause: signal?.reason });
-  const highWatermark = options.highWatermark ?? NumberMAX_SAFE_INTEGER;
-  validateInteger(highWatermark, 'options.highWatermark', 1);
-  const lowWatermark = options.lowWatermark ?? 1;
-  validateInteger(lowWatermark, 'options.lowWatermark', 1);
+  // Support both highWaterMark and highWatermark for backward compatibility
+  const highWatermark = options.highWaterMark ?? options.highWatermark ?? NumberMAX_SAFE_INTEGER;
+  validateInteger(highWatermark, 'options.highWaterMark', 1);
+  // Support both lowWaterMark and lowWatermark for backward compatibility
+  const lowWatermark = options.lowWaterMark ?? options.lowWatermark ?? 1;
+  validateInteger(lowWatermark, 'options.lowWaterMark', 1);
 
   // Preparing controlling queues and variables
   FixedQueue ??= require('internal/fixed_queue');

lib/internal/readline/interface.js

@@ -1359,7 +1359,7 @@ class Interface extends InterfaceConstructor {
       this[kLineObjectStream] = EventEmitter.on(
         this, 'line', {
           close: ['close'],
-          highWatermark: 1024,
+          highWaterMark: 1024,
           [kFirstEventParam]: true,
         });
     }