I am learning Angular unit test for chained promise . Here is code snippet and failed at expectation with error message Expected ” to equal ‘bar’. What is needed to make it success ? I have used Angular 17 and Jasmine.I have tried with fakeAsync with tick & flush .

it(`nested promise testing`, fakeAsync(() => {
let item = '';
const mockItem = {
promise: Promise.resolve(new Response(JSON.stringify({ foo: 'bar' }))),
};  
Promise.resolve(mockItem.promise)
.then((response) => response.json())
.then((data) => {
console.log('data = ' + data.foo);
item = data.foo;
});
flush();
//tick(500);
expect(item).toEqual('bar'); // Expected '' to equal 'bar'.
}));