Find differences in react prop and state updates

prop-state-diff.jsx

    public componentDidUpdate(prevProps, prevState) {
        console.log('Rrow update diff:');

        const nowProps = Object.entries(this.props);
        const addedProps = nowProps.filter(([key, val]) => {
            if (prevProps[key] === undefined) {
                return true;
            }
            if (prevProps[key] !== val) {
                console.log(`${key}
              - ${JSON.stringify(val)}
              + ${JSON.stringify(prevProps[key])}`);
            }
            return false;
        });
        addedProps.forEach(([key, val]) =>
            console.log(`${key}
              + ${JSON.stringify(val)}`)
        );

        const nowState = Object.entries(this.state);
        const addedState = nowState.filter(([key, val]) => {
            if (prevState[key] === undefined) {
                return true;
            }
            if (prevState[key] !== val) {
                console.log(`${key}
              - ${JSON.stringify(val)}
              + ${JSON.stringify(prevState[key])}`);
            }
            return false;
        });
        addedState.forEach(([key, val]) =>
            console.log(`${key}
              + ${JSON.stringify(val)}`)
        );
    }