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const arr2 = [1, 2, 3];

const arr1 = [4, 5, 6, 7, 8];

const [small, large] = arr1.length < arr2.length

    ? [arr1, arr2]

    : [arr2, arr1];

console.log(small == arr2); // [1, 2, 3] [4, 5, 6, 7, 8]

const mapToppings = new Map([

  ["queen", ["🐷", "🍄", "🍅", "🧀"]],

  ["cheese", ["🧀", "🍅"]],

  ["oriental", ["🍅", "🐑", "🍄", "🌶"]],

  ["royal", ["🍅", "🌵"]],

]);

const order1 = [

  { name: "queen", ingredients: mapToppings.get("queen") },

  { name: "cheese", ingredients: mapToppings.get("cheese") },

  { name: "oriental", ingredients: mapToppings.get("oriental") },

  { name: "royal", ingredients: mapToppings.get("royal") },

];

const order2 = [

  { name: "queen-promo", ingredients: mapToppings.get("queen") },

  { name: "royal-promo", ingredients: mapToppings.get("royal") },

];

function intersectionBy(a, b, keyFn) {

  const setB = new Set(b.map(keyFn));

  return a.filter((item) => setB.has(keyFn(item)));

}

const common = intersectionBy(order1,

                              order2,

                              (pizza) => pizza.ingredients);

console.log(common);

// [{ name: "queen", ingredients: [...] }, { name: "royal", ingredients: [...] }]