Register.js

// Actual Code  
constructor() {
    super();
    this.state = {
      name: "",
      email: "",
      password: "",
      password2: "",
      errors: {}
    };
  }

  // onChange method to link fields with state
  onChange = e => {
    this.setState({ [e.target.name]: e.target.value });
  };

  // Submitting the form
  onSubmit = e => {
    e.preventDefault();

    const newUser = {
      name: this.state.name,
      email: this.state.email,
      password: this.state.password,
      password2: this.state.password2
    };
  };
// What I want
  constructor() {
    super();
    this.state = {
      user: {
        name: "",
        email: "",
        password: "",
        password2: ""
      },
      errors: {}
    };
  }

  // onChange method to link fields with state
  onChange = e => {
    this.setState({ user[e.target.name]: e.target.value }); // This is what I want to do - this fails
  };

  // Submitting the form
  onSubmit = e => {
    e.preventDefault();

//  All of that so I can use spread operator instead of typing it
    const newUser = {
      ...this.state.user
    };
  }