ngReduxFake.js

export default class NgReduxFake {
  private selectedState: any;
  private target: any;
  private mapState: Function;

  push(selectedState: any) {
    if (!_.isPlainObject(selectedState)) {
      throw 'selectedState must be a plain object';
    }

    this.selectedState = selectedState;
    this.updateTarget();
  }

  connect(mapState: Function) {
    this.mapState = mapState;
    return (target) => {
      this.target = target;
      this.updateTarget();
    };
  }

  updateTarget() {
    if (!this.target || !this.mapState || !this.selectedState) {
      return;
    }

    if (_.isFunction(this.target)) {
      this.target(this.mapState(this.selectedState));
      return;
    }
    _.assign(this.target, this.mapState(this.selectedState));
  }
}

/*usage*/

let mockState;
let sut;
let ngRedux;

beforeEach(() => {
  mockState = {baz: {
    foo: true,
    bar: false
  }};
  ngRedux = new NgReduxFake();
  ngRedux.push(mockState);
  sut = new myController(ngRedux);
});

it('Should update foo', () => {
  mockState.baz.foo = false;
  ngRedux.push(mockState);
  assert.equal(sut.foo, mockState.baz.foo);
});