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Prevent native Error class hi-jacking in FS errors #40232

@SmashingQuasar

Description

@SmashingQuasar

Version

v16.9.0

Platform

Linux vagrant-docker 4.19.0-6-amd64 #1 SMP Debian 4.19.67-2+deb10u2 (2019-11-11) x86_64 GNU/Linux

Subsystem

fs

What steps will reproduce the bug?

In the current state of the promises section of the native fs module, when an error occurs, the native type Error is hi-jacked and a code property is being added to the error object.

This can easily be reproduced with the following code:

import { promises as FileSystem } from "fs";

try
{
    FileSystem.stat("/a/path/leading/to/nothing");
}
catch (error)
{
    console.log(Object.getPrototypeOf(error); // Will display the native class "Error"
    console.log(Object.getOwnPropertyDescriptors(error); // Will display the added code property that isn't native to Error.
}

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

No required conditions outside of the use of the fs native module.

What is the expected behavior?

This isn't a bug per-se but is a bad practice. A custom error of type FileSystemError should be thrown instead of hi-jacking the Error class to dynamically add a property to the object.
This behavior leads to problematic linting and testing with super-sets such as TypeScript or Eslint. Since code is not a native property of Error and dynamic property setting is often considered bad practice, it leads to situations where handling those specific issues requires extra effort to circumvent this design.

What do you see instead?

No response

Additional information

Ideally a custom FileSystemError should be created such as (Typescript example for types clarity):

class FileSystemError extends Error
{
    public code: string; // Ideally should be an enum listing all the possible values.
}

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    errorsIssues and PRs related to JavaScript errors originated in Node.js core.

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