React vs Recompose unit tests

CounterClass.js

export default class Counter extends React.Component {
  state = {
    counter: this.props.counter
  };

  increment = () => {
    this.setState(state => ({
      counter: state.counter + 1
    }));
  };

  decrement = () => {
    this.setState(state => ({
      counter: state.counter - 1
    }));
  };

  render() {
    return (
      <div>
        {this.state.counter}
        <button onClick={this.increment}>increment</button>
        <button onClick={this.decrement}>decrement</button>
      </div>
    
  }
}

CounterClass.test.js

describe("Counter component", () => {
  it("increments counter", () => {
    const component = shallow(<Counter counter={5} />);
    component.instance().increment();
    expect(component.instance().state.counter).toEqual(6);
  });

  it("decrements counter", () => {
    const component = shallow(<Counter counter={5} />);
    component.instance().decrement();
    expect(component.instance().state.counter).toEqual(4);
  });
});

CounterStateless.js

const CounterStatelessComponent = ({ counter, increment, decrement }) => {
  return (
    <div>
      {counter}
      <button onClick={increment}>increment</button>
      <button onClick={decrement}>decrement</button>
    </div>
  );
};

const withCounter = compose(
  withState("counter", "setCounter", 0),
  mapProps(({ counter, setCounter }) => {
    return {
      counter,
      increment: () => {
        setCounter(counter + 1);
      },
      decrement: () => {
        setCounter(counter - 1);
      }
    };
  })
);

export const CounterStateless = withCounter(CounterStatelessComponent);

CounterStateless.test.js

describe("Counter stateless", () => {
  it("increments counter", () => {
    const rootComponent = mount(<CounterStateless />);

    let component = rootComponent.find("CounterStatelessComponent");
    component.props().increment();

    rootComponent.update();

    component = rootComponent.find("CounterStatelessComponent");
    expect(component.props().counter).toEqual(1);
  });
});