[Bug]: TypeError encountered when logging class extending superclass which contains protected property

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TypeError

The problem

Regression in winston v3.7.1 caused the code shown further within to produce a TypeError.

See below error log:

      Object.assign(msg, this.defaultMeta, msgClone);
             ^

TypeError: Cannot assign to read only property 'canBeAnything' of object 'Error: This must not be empty'
    at Function.assign (<anonymous>)
    at DerivedLogger._addDefaultMeta (<PATH>/node_modules/winston/lib/winston/logger.js:639:14)
    at DerivedLogger.<computed> [as info] (<PATH>/node_modules/winston/lib/winston/create-logger.js:80:14)
    at Object.<anonymous> (<PATH>/index.js:31:5)
    at Module._compile (node:internal/modules/cjs/loader:1099:14)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1153:10)
    at Module.load (node:internal/modules/cjs/loader:975:32)
    at Function.Module._load (node:internal/modules/cjs/loader:822:12)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:77:12)
    at node:internal/main/run_main_module:17:47

What version of Winston presents the issue?

v3.7.1

What version of Node are you using?

v.17.8.0

If this worked in a previous version of Winston, which was it?

v3.6.0

Minimum Working Example

const {createLogger, format, transports} = require('winston');
const {json} = format;

const log = createLogger({
	level: 'info',
	defaultMeta: {service: 'database-service'},
	transports: [
		new transports.Console({
			format: json(),
			level: 'info',
		}),
	]
});

class SuperError extends Error {
	constructor() {
		super();
		Object.defineProperty(this, 'canBeAnything', { enumerable: true, value: ''});
	}
}

class ThisError extends SuperError {
	message;

	constructor() {
		super();
		this.message = "This must not be empty";
	}
}

log.info(new ThisError());

Additional information

This was encountered initially when using winston to report an error produced by mssql. mssql has their own error classes and when winston upticked from v3.6.0 to v3.7.1 it broke our error reporting.

Original code is closed source, but I have basically boiled down the minimum required to reproduce this error above.

Worth noting, perhaps, but extend Error is extra and I don’t believe it’s needed. Additionally, this TypeError is not reproduced if this.message is omitted or is equal to ''.

[maverick1872]

Successfully reproduced locally. Need to figure out how to get reproduced in a test environment but hoping to have a fix sorted out by Monday or so.

[WhiteMinds]

What is the progress of this issue? I still can’t use logger.child method to override defaultMeta.