检查按钮是否在 react-testing-library 中被禁用

Question

I have a React component that generates a button, which content contains <span> element like this one:

function Click(props) {
    return (
        <button disable={props.disable}>
            <span>Click me</span>
        </button>
    );
}

I want to test the logic of this component with the use of react-testing-library and mocha + chai .

The problem which I stuck at the moment is that getByText("Click me") selector return the <span> DOM node, but for the tests, I need to check disable attribute of the <button> node. What is the best practice handling such test cases? I see a couple of solutions, but all of them sounds a little bit off:

1. Use data-test-id for <button> element
2. Select one of the ancestors of the <Click /> component and then select the button within(...) this scope
3. Click on the selected element with fireEvent and check that nothing is happened

Can you suggest a better approach?

Answer 1

Assert if button is disabled

You can use the toHaveAttribute and closest to test it.

import { render } from '@testing-library/react';

const { getByText } = render(Click);
expect(getByText(/Click me/i).closest('button')).toHaveAttribute('disabled');

or toBeDisabled

expect(getByText(/Click me/i).closest('button')).toBeDisabled();

---

Assert if button is enabled

To check if the button is enabled, use not as follows

expect(getByText(/Click me/i).closest('button')).not.toBeDisabled();

Answer 2

You can use toBeDisabled() from @testing-library/jest-dom , it is a custom jest matcher to test the state of the DOM:

https://github.com/testing-library/jest-dom

Example:

<button>Submit</button>

expect(getByText(/submit/i)).toBeDisabled()

Answer 3

For someone who looking for the test which is the button is not disabled .

import { render } from '@testing-library/react';

const { getByText } = render(Click);
expect(getByText(/Click me/i).getAttribute("disabled")).toBe(null)

Answer 4

You can test the disable prop of the button just by using @testing-library/react as follows.

example:

   import { render } from '@testing-library/react';

   const {getByText} = render(<Click/>)

   expect(getByText('Click me').closest('button').disabled).toBeTruthy()

Answer 5

I would politely argue you are testing an implementation detail, which react-testing-library discourages.

The more your tests resemble the way your software is used, the more confidence they can give you.

If a button is disabled, a user doesn't see a disabled prop, instead they see nothing happen. If a button is enabled, a user doesn't see the omission of a disabled prop, instead they see something happen.

I believe you should be testing for this instead:

const Button = (props) => (
  <button 
    type="submit" 
    onClick={props.onClick} 
    disabled={props.disabled}
  >
    Click me
  </button>
);

describe('Button', () => {
  it('will call onClick when enabled', () => {
    const onClick = jest.fn();
    render(<Button onClick={onClick} disabled={false} />);
    userEvent.click(getByRole('button', /click me/i));
    expect(onClick).toHaveBeenCalledTimes(1);
  });

  it('will not call onClick when disabled', () => {
    const onClick = jest.fn();
    render(<Button onClick={onClick} disabled={true} />);
    userEvent.click(getByRole('button', /click me/i));
    expect(onClick).not.toHaveBeenCalled();
  });
})

Answer 6

Another way to fix this would be to grab by the role and check the innerHTML like,

const { getByRole } = render(<Click />)
const button = getByRole('button')

// will make sure the 'Click me' text is in there somewhere
expect(button.innerHTML).toMatch(/Click me/))

This isn't the best solution for your specific case, but it's one to keep in your back pocket if you have to deal with a button component that's not an actual button, eg,

<div role="button"><span>Click Me</span></div>

Answer 7

toHaveAttribute is good option in using attribute.

<button data-testid="ok-button" type="submit" disabled>ok</button>

const button = getByTestId('ok-button')
//const button = getByRole('button');

expect(button).toHaveAttribute('disabled')
expect(button).toHaveAttribute('type', 'submit')
expect(button).not.toHaveAttribute('type', 'button')

expect(button).toHaveAttribute('type', expect.stringContaining('sub'))
expect(button).toHaveAttribute('type', expect.not.stringContaining('but'))

Hope this will be helpful.