extendable-error-class

Extend the Error Class with ES2015/ES5/Babel, i.e. fix for `class MyError extends Error{}`

Usage no npm install needed!

<script type="module">
  import extendableErrorClass from 'https://cdn.skypack.dev/extendable-error-class';
</script>

README

Usage

const ExtendableError = require('extendable-error-class');

class MyError extends ExtendableError {
    constructor(m) {
        super(m);
        
        // Optional - ExtendableError sets `name` to your class's name itself,
        // but minification, etc. can change that, so you may want to do it
        // explicitly.
        this.name = 'MyError';
    }
}

extendable-error-class has no dependencies.

Why

Because the following doesn't work as expected.

class MyError extends Error {
    constructor(m) {
        super(m);
    }
}

How

The workaround is based on babel-plugin-transform-builtin-extend and following code

const ExtendableError = class extends Error {
    constructor(message) {
        super(message);
        this.name = this.constructor.name;
        this.message = message;
        if (typeof Error.captureStackTrace === 'function') {
            Error.captureStackTrace(this, this.constructor);
        } else {
            this.stack = (new Error(message)).stack;
        }
    }
};

The code is already compiled with babel and babel-plugin-transform-builtin-extend. Therefore one is able to use this workaround without adding any dependency.

See http://stackoverflow.com/questions/31089801/extending-error-in-javascript-with-es6-syntax