React-testing-library: Entire error output to console during a .toThrow() assertion

[good-idea]

• react-testing-library version: 5.0.0
• react version: 16.4.2
• node version: 8.11.3
• npm (or yarn) version: yarn 1.9.4

Relevant code or config:

const Component = props => {
    if (props.throw) throw new Error('!!')
    return <div>😀</div>
}

it('Throws an error when `props.throw === true`', () => {
    const renderComponent = () => render(<Component throw />)
    expect(renderComponent).toThrow('!!')
})

What you did:

I'm making a jest assertion that a component will throw an error under certain circumstances.

What happened:

While the test itself passes, the entire error shows up in the Jest output. Under other circumstances, jest suppresses errors that are thrown within a .toThrow() assertion. (there's a test in the repo that shows this)

Reproduction:

https://github.com/good-idea/rtl-throws-error

Problem description:

Lots of unnecessary console output!

Suggested solution:

I haven't looked into how jest / RTL handles all of this and how it might be happening, but I'm happy to put together a PR. Just point me in the right direction!

[kentcdodds]

This actually is not something that has anything to do with react-testing-library. It's how react and jsdom work. You can silence these logs using mock functions. That's what I do.

[good-idea]

Oh, got it ~ I hadn't come across this until I started using react-testing-library so I thought it was a problem on that side.

Thanks for the quick response!

[good-idea]

For anyone else coming here with the same problem, putting this in my setup file has it work exactly as I'd expect:

console.error = err => { throw new Error(err); };
console.warn = warning => { throw new Error(warning); };

[wheelmaker24]

This actually is not something that has anything to do with react-testing-library. It's how react and jsdom work. You can silence these logs using mock functions. That's what I do.

For everyone wondering: This is an easy way to do it: https://til.hashrocket.com/posts/hrhejhqg2n-turn-off-console-error-messages-in-a-test