Passing an event object to enzyme .simulate

Question

I am using Jest and Enzyme to test a React checkbox component.

This is my test:

it('triggers checkbox onChange event', () => {   const configs = {     default: true,     label: 'My Label',     element: 'myElement',   }   const checkbox = shallow(     <CheckBox       configs={configs}     />   )   checkbox.find('input').simulate('click') }) 

I get this error however when running the test:

TypeError: Cannot read property 'target' of undefined 

This is the input for my component:

<div className="toggle-btn sm">   <input      id={this.props.configs.element}      className="toggle-input round"      type="checkbox"      defaultChecked={ this.props.defaultChecked }      onClick={ e => this.onChange(e.target) }   >   </input> </div> 

I think that I need to pass an event as the second object to simulate but I am not sure how to do this.

Thanks

Answer 1

simulate function takes other arguments which will be passed to the event handler. You can mock your event. E.g.:

const mockedEvent = { target: {} } checkbox.find('input').simulate('click', mockedEvent)