Jest error '' TypeError: Cannot read property 'preventDefault' of undefined "

Question

I have a function as bellow and when i going to test the function i got the above error.

function

toggleRecovery = e => {
    e.preventDefault()
    this.setState(
      {
        recovery: !this.state.recovery
      },
      () => {
        this.props.reset()
      }
    )
  }

test

test('if the recovery state is true should set the state to the false', () => {
      wrapper.setState({ recovery: true })
      //Check if the state is true initially
      expect(wrapper.state().recovery).toBeTruthy()
      //Calling the toggleRecovery()
      wrapper.instance().toggleRecovery()
      expect(wrapper.state().recovery).toBeFalsy()
      expect(props.reset).toHaveBeenCalled()
    })

error

TypeError: Cannot read property 'preventDefault' of undefined

How can i overcome this error and what is cause the above error

Answer 1

While calling toggleRecovery on instance you can pass the preventDefault mock like

test('if the recovery state is true should set the state to the false', () => {
      wrapper.setState({ recovery: true })
      //Check if the state is true initially
      expect(wrapper.state().recovery).toBeTruthy()
      //Calling the toggleRecovery()
      wrapper.instance().toggleRecovery({ 
          preventDefault: () => {
      })
      expect(wrapper.state().recovery).toBeFalsy()
      expect(props.reset).toHaveBeenCalled()
    })