[Bug] Remove the incorrect event listener.

[peng-huang-ch]

• Version: v15.4.0
• Platform: MacOS V10.15.7
• Subsystem: lib/events.js

What steps will reproduce the bug?

const EventEmitter = require('events');
const ee = new EventEmitter();
// const symbol = Symbol('listener');
const symbol = 'listener';

const fn2 = function(...args) {
    console.log('Call fn2', ...args)
};

const fn = function (...args) {
    console.log('Call fn', ...args);
};

fn[symbol] = fn2;

ee.on('one', fn2)
ee.on('one', fn);
ee.emit('one');
// Prints: 
//    Call fn2
//    Call fn

console.log('1. remove fn2')
ee.removeListener('one', fn2); // fn is removed, expect remove the fn2 
ee.emit('one');
// Prints: 
//    Call fn2

console.log('2. remove fn2 again')
ee.removeListener('one', fn2) // fn2 is removed
ee.emit('one')
// Prints: 
//    Call fn2

console.log('3. remove fn2 again');
ee.emit('one')

How often does it reproduce? Is there a required condition?

Occurs every time.

What is the expected behavior?

Call fn2
Call fn
1. remove fn2
Call fn
2. remove fn2 again
Call fn
3. remove fn2 again
Call fn

What do you see instead?

Call fn2
Call fn
1. remove fn2
Call fn2
2. remove fn2 again
3. remove fn2 again

Additional information

Replace the listener attribute of event listener with symbol

[yashLadha]

Would like to solve this issue, seems userland is updating the attributes needed by the interface.

[peng-huang-ch]

I have created a pr #36558, could you help to review it, THX.

[yashLadha]

Sure @peng-huang-cc