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reactjs - React.useState does not reload state from props

I'm expecting state to reload on props change, but this does not work and user variable is not updated on next useState call, what is wrong?

function Avatar(props) {
  const [user, setUser] = React.useState({...props.user});
  return user.avatar ? 
         (<img src={user.avatar}/>)
        : (<p>Loading...</p>);
}

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The argument passed to useState is the initial state much like setting state in constructor for a class component and isn't used to update the state on re-render

If you want to update state on prop change, make use of useEffect hook

function Avatar(props) {
  const [user, setUser] = React.useState({...props.user});

  React.useEffect(() => {
      setUser(props.user);
  }, [props.user])

  return user.avatar ? 
         (<img src={user.avatar}/>)
        : (<p>Loading...</p>);
}

Working demo


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