如何根据筛选出的键向TypeScript推断一个属性只能属于一种类型？

interface Circle {
  kind: "circle";
  radius: number;
}

interface Square {
  kind: "square";
  sideLength: number;
}

type Shape = Circle | Square;

function calculateArea(shape: Shape) {
  if (shape.kind === "circle") {
    // 在这里，TypeScript会推断shape为Circle类型
    return Math.PI * shape.radius * shape.radius;
  } else if (shape.kind === "square") {
    // 在这里，TypeScript会推断shape为Square类型
    return shape.sideLength * shape.sideLength;
  }
}

const circle: Circle = {
  kind: "circle",
  radius: 5,
};

const square: Square = {
  kind: "square",
  sideLength: 10,
};

console.log(calculateArea(circle)); // 输出78.53981633974483
console.log(calculateArea(square)); // 输出100