const onSubmitClick = async () => {
var { isSuccess, result } = await callDispatch();
if (isSuccess) {
setValidStatus(true);
}
};

async function callDispatch() {
const result = call to server;
let isSuccess = result.success || (result.response && result.response.data.success);
return { isSuccess, result };
}

and in my test file

 import { EnterPin } from '../pages/enter-pin';
 jest.spyOn(EnterPin.prototype, 'callDispatch').mockImplementation(() =>{
  return 'true'
})
var button  = screen.getByRole('button');
fireEvent.click(button);

but i am getting Cannot spyOn on a primitive value; undefined given I tried below too but it didnot work

jest.spyOn(EnterPin.prototype, 'callDispatch').mockImplementation(() =>{
  return 'true'
})
var button  = screen.getByRole('button');
fireEvent.click(button);