test.tsx

// So you have such component

const component = () => {
  const [robotFaceDirection, setRobotFaceDirection] = useState<number>(0);
  const [robotPositionX, setRobotPositionX] = useState<number>(0);
  const [robotPositionY, setRobotPositionY] = useState<number>(0);

  const handleOnInputXChange = (event: any) => {
    const value = event.currentTarget.value;
    setRobotPositionX(Number(value));
  };

  const handleOnInputYChange = (event: any) => {
    const value = event.currentTarget.value;
    setRobotPositionY(Number(value));
  };

  const handleSelectedFace = (value: any) => {
    setRobotFaceDirection(Number(value));
  };

  const handlePlaceCommand = () => {
    onPlaceRobotPost(robotPositionX, robotPositionY, robotFaceDirection);
  };
    // Some Return there.
  }
// Problem with that, you have no access to state to check its value
// BUT you can decouple that logic above from render with hook
  
const useRobotPosition = () => {
  const component = () => {
const [robotFaceDirection, setRobotFaceDirection] = useState<number>(0);
  const [robotPositionX, setRobotPositionX] = useState<number>(0);
  const [robotPositionY, setRobotPositionY] = useState<number>(0);

  const handleOnInputXChange = (event: any) => {
    const value = event.currentTarget.value;
    setRobotPositionX(Number(value));
  };

  const handleOnInputYChange = (event: any) => {
    const value = event.currentTarget.value;
    setRobotPositionY(Number(value));
  };

  const handleSelectedFace = (value: any) => {
    setRobotFaceDirection(Number(value));
  };

  const handlePlaceCommand = () => {
    onPlaceRobotPost(robotPositionX, robotPositionY, robotFaceDirection);
  };
  return { robotFaceDirection, robotPositionX, robotPositionY, //etc, whatever you need}
  }
}
// As hook returns state you can just get the state and test it, https://github.com/testing-library/react-hooks-testing-library
    
// In render component instead of having all that states you just use hook
 const { robotFaceDirection, robotPositionX, robotPositionY, //etc, whatever you need } = useRobotPosition()