@happy-dom/uncaught-exception-observer

:warning: This package has been deprecated. Happy DOM now supports this feature built in by setting "errorCapture" to "processLevel". :warning:

About

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. It includes many web standards from WHATWG DOM and HTML.

The goal of Happy DOM is to emulate enough of a web browser to be useful for testing, scraping web sites and server-side rendering.

Happy DOM focuses heavily on performance and can be used as an alternative to JSDOM.

This package contains a tool that can observe uncaught exceptions and Promise rejections in Happy DOM. It will dispatch uncaught errors as events on the Happy DOM Window instance.

Uncaught exceptions and rejections must be listened to on the NodeJS process at a global level. This tool will therefore not work in all environments as there may already be listeners added by other libraries on the NodeJS process that may conflict.

DOM Features

• Custom Elements (Web Components)

• Shadow Root (Shadow DOM)

• Declarative Shadow DOM

• Mutation Observer

• Tree Walker

• Fetch

And much more..

Works With

• Google LitHTML

• Google LitElement

• React

• Angular

• Vue

Module Systems

• ESM
• CommonJS

Installation

npm install happy-dom @happy-dom/uncaught-exception-observer

Usage

import { Window } from "happy-dom";
import { UncaughtExceptionObserver } from "@happy-dom/uncaught-exception-observer";

const window = new Window();
const document = window.document;
const observer = new UncaughtExceptionObserver();

// Connects observer
observer.observe(window);

window.addEventListener((error) => {
	// Do something on error
});

document.write(`
    <script>
        (() => {
            async function main() {
                await fetch('https://localhost:3000/')
                throw Error('This error will be caught, but would otherwise have terminated the process.');
            }

            main();
        })();
    </script>
`);

// Disconnects observer
observer.disconnect();

Documentation

Read more about how Happy DOM works in our documentation.

Performance

Operation	JSDOM	Happy DOM
Import / Require	333 ms	45 ms
Parse HTML	256 ms	26 ms
Serialize HTML	65 ms	8 ms
Render custom element	214 ms	19 ms
querySelectorAll('tagname')	4.9 ms	0.7 ms
querySelectorAll('.class')	6.4 ms	3.7 ms
querySelectorAll('[attribute]')	4.0 ms	1.7 ms
querySelectorAll('[class~="name"]')	5.5 ms	2.9 ms
querySelectorAll(':nth-child(2n+1)')	10.4 ms	3.8 ms

See how the test was done here

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