import { DyNTS_SingletonServiceBase } from './singleton.service-base';

class TestSingletonService extends DyNTS_SingletonServiceBase {
  static getInstance(): TestSingletonService {
    return TestSingletonService.getSingletonInstance();
  }
}

describe('| DyNTS_SingletonServiceBase', () => {
  it('| should return the same instance on multiple calls', () => {
    const instance1 = TestSingletonService.getInstance();
    const instance2 = TestSingletonService.getInstance();

    expect(instance1).toBe(instance2);
    expect(instance1).toBeInstanceOf(TestSingletonService);
  });

  it('| should create instance only once', () => {
    const instance1 = TestSingletonService.getInstance();
    const instance2 = TestSingletonService.getInstance();
    const instance3 = TestSingletonService.getInstance();

    expect(instance1).toBe(instance2);
    expect(instance2).toBe(instance3);
  });
});