eventTest.test.js

//Reusable resize event handler function
const resizeWindowTestFunc = (width, height) => {
  window.innerWidth = width;
  window.innerHeight = height;
  window.dispatchEvent(new Event('resize'));
};
it('Test for event',()=>{
  //Before resizing here call the function with resize event
  resizeWindowTestFunc(450, 450)
  //After resizing here call the function with resize event
});