import { of } from 'rxjs';
import { distinct, tap, toArray } from 'rxjs/operators';

describe('rx.distinct', () => {

    interface TestObject {
        key1: string;
        key2: string;
    }

    it('should allow chaining', () => {

        const t1: TestObject = {
            key1: 'a1',
            key2: 'b1'
        };

        const t2: TestObject = {
            key1: 'a2',
            key2: 'b1'
        };

        const t3: TestObject = {
            key1: 'a3',
            key2: 'b2'
        };

        const t4: TestObject = {
            key1: 'a2',
            key2: 'b3'
        };

        return of(t1, t2, t3, t4).pipe(
            distinct(o => o.key1),
            distinct(o => o.key2),
            toArray(),
            tap(a => {
                expect(a.length).toEqual(2);
            })).toPromise();
    });
});