How to test a getter and setter in Jest (Angular)

I am trying to test a getter / setter value after it change. All test are fine except the last one in comments.

What can I do to make this an successful test. Do I need use an Spy or something else to achieve this. Can someone point me in the right direction

Also can must I update the other tests with kind of spy or mockdata.

TS:

export class component001 {
isLastRecord = false;

private _records: Records[];
@Input()
set records(value: Record[]){
if(value) {
this._records = value;
this.isLastRecord = value.filter(r => r.type === 'type001').length === 1;
}
}
get records(): Record[] {
return this._records;
}
}


Jest:

describe("component001", () => {
let component: Component001;
let fixture: ComponentFixture<Component001>;

beforeEach(async () => {
await TestBed.configureTestingModule({
imports: [Component001, HttpClientTestingModule]
}).compileComponents();
});

beforeEach(() => {
fixture = TestBed.createComponent(Component001);
component = fixture.componentInstance;
fixture.detectChanges();
});

describe('Component001', () => {
it('Should return true when there the count of record changes from 2 to 1 record', () => {
let mockRecords = [
{ name: 'Barbara Gordon', type: 'type001' },
{ name: 'Cassandra Cain', type: 'type001'}
] as unknown as Record [];

expect(component.isLastRecord).toBe(false);
component.dnsRecords = mockRecords;
expect(component.isLastRecord).toBe(false);
component.dnsRecords = [mockRecords.pop()];
expect(component.isLastRecord).toBe(true);
});

// it('Should return true when there the count of record changes from 1 to 2 records', () => {
// let mockRecords = [
// { name: 'Barbara Gordon', type: 'type001' }
// ] as unknown as Record [];

// expect(component.isLastRecord).toBe(false);
// component.Records = mockRecords;
// expect(component.isLastRecord).toBe(true);

// const newRecord = {name: 'Cassandra Cain', type: 'type001'} as unknown as Record;
// component.records.push(newRecord);
// expect(component.isLastRecord).toBe(false);
// });

});
})


Also I am using angular 16 with standalone components

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