bun.sh/test/bun.js/decorators.test.ts

// @ts-nocheck
import { test, expect } from "bun:test";

test("decorator order of evaluation", () => {
  let counter = 0;
  const computedProp: unique symbol = Symbol("computedProp");

  @decorator1
  @decorator2
  class BugReport {
    @decorator7
    type: string;

    @decorator3
    x: number = 20;

    @decorator5
    private _y: number = 12;

    @decorator10
    get y() {
      return this._y;
    }
    @decorator11
    set y(newY: number) {
      this._y = newY;
    }

    @decorator9
    [computedProp]: string = "yes";

    constructor(@decorator8 type: string) {
      this.type = type;
    }

    @decorator6
    move(newX: number, @decorator12 newY: number) {
      this.x = newX;
      this._y = newY;
    }

    @decorator4
    jump() {
      this._y += 30;
    }
  }

  function decorator1(target, propertyKey) {
    expect(counter++).toBe(11);
    expect(target === BugReport).toBe(true);
    expect(propertyKey).toBe(undefined);
  }

  function decorator2(target, propertyKey) {
    expect(counter++).toBe(10);
    expect(target === BugReport).toBe(true);
    expect(propertyKey).toBe(undefined);
  }

  function decorator3(target, propertyKey) {
    expect(counter++).toBe(1);
    expect(target === BugReport.prototype).toBe(true);
    expect(propertyKey).toBe("x");
  }

  function decorator4(target, propertyKey) {
    expect(counter++).toBe(8);
    expect(target === BugReport.prototype).toBe(true);
    expect(propertyKey).toBe("jump");
  }

  function decorator5(target, propertyKey) {
    expect(counter++).toBe(2);
    expect(target === BugReport.prototype).toBe(true);
    expect(propertyKey).toBe("_y");
  }

  function decorator6(target, propertyKey) {
    expect(counter++).toBe(7);
    expect(target === BugReport.prototype).toBe(true);
    expect(propertyKey).toBe("move");
  }

  function decorator7(target, propertyKey) {
    expect(counter++).toBe(0);
    expect(target === BugReport.prototype).toBe(true);
    expect(propertyKey).toBe("type");
  }

  function decorator8(target, propertyKey) {
    expect(counter++).toBe(9);
    expect(target === BugReport).toBe(true);
    expect(propertyKey).toBe(undefined);
  }

  function decorator9(target, propertyKey) {
    expect(counter++).toBe(5);
    expect(target === BugReport.prototype).toBe(true);
    expect(propertyKey).toBe(computedProp);
  }

  function decorator10(target, propertyKey) {
    expect(counter++).toBe(3);
    expect(target === BugReport.prototype).toBe(true);
    expect(propertyKey).toBe("y");
  }

  function decorator11(target, propertyKey) {
    expect(counter++).toBe(4);
    expect(target === BugReport.prototype).toBe(true);
    expect(propertyKey).toBe("y");
  }

  function decorator12(target, propertyKey) {
    expect(counter++).toBe(6);
    expect(target === BugReport.prototype).toBe(true);
    expect(propertyKey).toBe("move");
  }
});

test("decorator factories order of evaluation", () => {
  let counter = 0;
  const computedProp: unique symbol = Symbol("computedProp");

  @decorator1()
  @decorator2()
  class BugReport {
    @decorator7()
    type: string;

    @decorator3()
    x: number = 20;

    @decorator5()
    private _y: number = 12;

    @decorator10()
    get y() {
      return this._y;
    }
    @decorator11()
    set y(newY: number) {
      this._y = newY;
    }

    @decorator9()
    [computedProp]: string = "yes";

    constructor(@decorator8() type: string) {
      this.type = type;
    }

    @decorator6()
    move(newX: number, @decorator12() newY: number) {
      this.x = newX;
      this._y = newY;
    }

    @decorator4()
    jump() {
      this._y += 30;
    }
  }

  function decorator1() {
    expect(counter++).toBe(18);
    return function (target, descriptorKey) {
      expect(counter++).toBe(23);
    };
  }

  function decorator2() {
    expect(counter++).toBe(19);
    return function (target, descriptorKey) {
      expect(counter++).toBe(22);
    };
  }

  function decorator3() {
    expect(counter++).toBe(2);
    return function (target, descriptorKey) {
      expect(counter++).toBe(3);
    };
  }

  function decorator4() {
    expect(counter++).toBe(16);
    return function (target, descriptorKey) {
      expect(counter++).toBe(17);
    };
  }

  function decorator5() {
    expect(counter++).toBe(4);
    return function (target, descriptorKey) {
      expect(counter++).toBe(5);
    };
  }

  function decorator6() {
    expect(counter++).toBe(12);
    return function (target, descriptorKey) {
      expect(counter++).toBe(15);
    };
  }

  function decorator7() {
    expect(counter++).toBe(0);
    return function (target, descriptorKey) {
      expect(counter++).toBe(1);
    };
  }

  function decorator8() {
    expect(counter++).toBe(20);
    return function (target, descriptorKey) {
      expect(counter++).toBe(21);
    };
  }

  function decorator9() {
    expect(counter++).toBe(10);
    return function (target, descriptorKey) {
      expect(counter++).toBe(11);
    };
  }

  function decorator10() {
    expect(counter++).toBe(6);
    return function (target, descriptorKey) {
      expect(counter++).toBe(7);
    };
  }

  function decorator11() {
    expect(counter++).toBe(8);
    return function (target, descriptorKey) {
      expect(counter++).toBe(9);
    };
  }

  function decorator12() {
    expect(counter++).toBe(13);
    return function (target, descriptorKey) {
      expect(counter++).toBe(14);
    };
  }
});

test("parameter decorators", () => {
  let counter = 0;
  class HappyDecorator {
    width: number;
    height: number;
    x: number;
    y: number;

    move(@d4 x: number, @d5 @d6 y: number) {
      this.x = x;
      this.y = y;
    }

    constructor(
      one: number,
      two: string,
      three: boolean,
      @d1 @d2 width: number,
      @d3 height: number,
    ) {
      this.width = width;
      this.height = height;
    }

    dance(@d7 @d8 intensity: number) {
      this.width *= intensity;
      this.height *= intensity;
    }
  }

  function d1(target, propertyKey, parameterIndex) {
    expect(counter++).toBe(7);
    expect(target === HappyDecorator).toBe(true);
    expect(propertyKey).toBe(undefined);
    expect(parameterIndex).toBe(3);
  }

  function d2(target, propertyKey, parameterIndex) {
    expect(counter++).toBe(6);
    expect(target === HappyDecorator).toBe(true);
    expect(propertyKey).toBe(undefined);
    expect(parameterIndex).toBe(3);
  }

  function d3(target, propertyKey, parameterIndex) {
    expect(counter++).toBe(5);
    expect(target === HappyDecorator).toBe(true);
    expect(propertyKey).toBe(undefined);
    expect(parameterIndex).toBe(4);
  }

  function d4(target, propertyKey, parameterIndex) {
    expect(counter++).toBe(2);
    expect(target === HappyDecorator.prototype).toBe(true);
    expect(propertyKey).toBe("move");
    expect(parameterIndex).toBe(0);
  }

  function d5(target, propertyKey, parameterIndex) {
    expect(counter++).toBe(1);
    expect(target === HappyDecorator.prototype).toBe(true);
    expect(propertyKey).toBe("move");
    expect(parameterIndex).toBe(1);
  }

  function d6(target, propertyKey, parameterIndex) {
    expect(counter++).toBe(0);
    expect(target === HappyDecorator.prototype).toBe(true);
    expect(propertyKey).toBe("move");
    expect(parameterIndex).toBe(1);
  }

  function d7(target, propertyKey, parameterIndex) {
    expect(counter++).toBe(4);
    expect(target === HappyDecorator.prototype).toBe(true);
    expect(propertyKey).toBe("dance");
    expect(parameterIndex).toBe(0);
  }

  function d8(target, propertyKey, parameterIndex) {
    expect(counter++).toBe(3);
    expect(target === HappyDecorator.prototype).toBe(true);
    expect(propertyKey).toBe("dance");
    expect(parameterIndex).toBe(0);
  }

  class Maybe {
    constructor(
      @m1 private x: number,
      @m2 public y: boolean,
      @m3 protected z: string,
    ) {}
  }

  function m1(target, propertyKey, index) {
    expect(target === Maybe).toBe(true);
    expect(propertyKey).toBe(undefined);
    expect(index).toBe(0);
  }

  function m2(target, propertyKey, index) {
    expect(target === Maybe).toBe(true);
    expect(propertyKey).toBe(undefined);
    expect(index).toBe(1);
  }

  function m3(target, propertyKey, index) {
    expect(target === Maybe).toBe(true);
    expect(propertyKey).toBe(undefined);
    expect(index).toBe(2);
  }
});

test("decorators random", () => {
  @Frozen
  class IceCream {}

  function Frozen(constructor: Function) {
    Object.freeze(constructor);
    Object.freeze(constructor.prototype);
  }

  expect(Object.isFrozen(IceCream)).toBe(true);

  class IceCreamComponent {
    @Emoji()
    flavor = "vanilla";
  }

  // Property Decorator
  function Emoji() {
    return function (target: Object, key: string | symbol) {
      let val = target[key];

      const getter = () => {
        return val;
      };
      const setter = (next) => {
        val = `🍦 ${next} 🍦`;
      };

      Object.defineProperty(target, key, {
        get: getter,
        set: setter,
        enumerable: true,
        configurable: true,
      });
    };
  }

  const iceCream = new IceCreamComponent();
  expect(iceCream.flavor === "🍦 vanilla 🍦").toBe(true);
  iceCream.flavor = "chocolate";
  expect(iceCream.flavor === "🍦 chocolate 🍦").toBe(true);

  const i: unique symbol = Symbol.for("i");
  const h: unique symbol = Symbol.for("h");
  const t: unique symbol = Symbol.for("t");
  const q: unique symbol = Symbol.for("q");
  const p: unique symbol = Symbol.for("p");
  const u3: unique symbol = Symbol.for("u3");
  const u5: unique symbol = Symbol.for("u5");
  const u6: unique symbol = Symbol.for("u6");
  const u8: unique symbol = Symbol.for("u8");

  class S {
    @StringAppender("😛") k = 35;
    @StringAppender("🤠") static j = 4;
    @StringAppender("😵‍💫") private static [h] = 30;
    @StringAppender("🤯") private static u = 60;
    @StringAppender("🤪") private [t] = 32;
    @StringAppender("🤑") [i] = 8;
    @StringAppender("🎃") private e = 10;
    @StringAppender("👻") static [q] = 202;
    @StringAppender("😇") r = S[h];
    _y: number;
    @StringAppender("🤡") get y() {
      return this._y;
    }
    set y(next) {
      this._y = next;
    }
    #o = 100;

    @StringAppender("😍") u1: number;
    @StringAppender("🥳") static u2: number;
    @StringAppender("🤓") private static [u3]: number;
    @StringAppender("🥺") private static u4: number;
    @StringAppender("🤯") private [u5]: number;
    @StringAppender("🤩") [u6]: number;
    @StringAppender("☹️") private u7: number;
    @StringAppender("🙃") static [u8]: number;

    @StringAppender("🤔") u9 = this.u1;
    @StringAppender("🤨") u10 = this.u2;
    @StringAppender("🙂") u11 = S[u3];
    @StringAppender("🙁") u12 = S.u4;
    @StringAppender("😐") u13 = this[u5];
    @StringAppender("😑") u14 = this[u6];
    @StringAppender("😶") u15 = this.u7;
    @StringAppender("😏") u16 = S[u8];

    constructor() {
      this.k = 3;
      expect(this.k).toBe("3 😛");
      expect(S.j).toBe(4);
      expect(this[i]).toBe("8 🤑");
      expect(this.e).toBe("10 🎃");
      expect(S[h]).toBe(30);
      expect(S.u).toBe(60);
      expect(this[t]).toBe("32 🤪");
      expect(S[q]).toBe(202);
      expect(this.#o).toBe(100);
      expect(this.r).toBe("30 😇");
      expect(this.y).toBe(undefined);
      this.y = 100;
      expect(this.y).toBe(100);

      expect(this.u1).toBe(undefined);
      expect(S.u2).toBe(undefined);
      expect(S[u3]).toBe(undefined);
      expect(S.u4).toBe(undefined);
      expect(this[u5]).toBe(undefined);
      expect(this[u6]).toBe(undefined);
      expect(this.u7).toBe(undefined);
      expect(S[u8]).toBe(undefined);

      expect(this.u9).toBe("undefined 🤔");
      expect(this.u10).toBe("undefined 🤨");
      expect(this.u11).toBe("undefined 🙂");
      expect(this.u12).toBe("undefined 🙁");
      expect(this.u13).toBe("undefined 😐");
      expect(this.u14).toBe("undefined 😑");
      expect(this.u15).toBe("undefined 😶");
      expect(this.u16).toBe("undefined 😏");

      this.u1 = 100;
      expect(this.u1).toBe("100 😍");
      S.u2 = 100;
      expect(S.u2).toBe("100 🥳");
      S[u3] = 100;
      expect(S[u3]).toBe("100 🤓");
      S.u4 = 100;
      expect(S.u4).toBe("100 🥺");
      this[u5] = 100;
      expect(this[u5]).toBe("100 🤯");
      this[u6] = 100;
      expect(this[u6]).toBe("100 🤩");
      this.u7 = 100;
      expect(this.u7).toBe("100 ☹️");
      S[u8] = 100;
      expect(S[u8]).toBe("100 🙃");

      expect(this.u9).toBe("undefined 🤔");
      expect(this.u10).toBe("undefined 🤨");
      expect(this.u11).toBe("undefined 🙂");
      expect(this.u12).toBe("undefined 🙁");
      expect(this.u13).toBe("undefined 😐");
      expect(this.u14).toBe("undefined 😑");
      expect(this.u15).toBe("undefined 😶");
      expect(this.u16).toBe("undefined 😏");
    }
  }

  let s = new S();
  expect(s.u9).toBe("undefined 🤔");
  expect(s.u10).toBe("undefined 🤨");
  expect(s.u11).toBe("undefined 🙂");
  expect(s.u12).toBe("undefined 🙁");
  expect(s.u13).toBe("undefined 😐");
  expect(s.u14).toBe("undefined 😑");
  expect(s.u15).toBe("undefined 😶");
  expect(s.u16).toBe("undefined 😏");

  s.u9 = 35;
  expect(s.u9).toBe("35 🤔");
  s.u10 = 36;
  expect(s.u10).toBe("36 🤨");
  s.u11 = 37;
  expect(s.u11).toBe("37 🙂");
  s.u12 = 38;
  expect(s.u12).toBe("38 🙁");
  s.u13 = 39;
  expect(s.u13).toBe("39 😐");
  s.u14 = 40;
  expect(s.u14).toBe("40 😑");
  s.u15 = 41;
  expect(s.u15).toBe("41 😶");
  s.u16 = 42;
  expect(s.u16).toBe("42 😏");

  function StringAppender(emoji: string) {
    return function (target: Object, key: string | symbol) {
      let val = target[key];

      const getter = () => {
        return val;
      };
      const setter = (value) => {
        val = `${value} ${emoji}`;
      };

      Object.defineProperty(target, key, {
        get: getter,
        set: setter,
        enumerable: true,
        configurable: true,
      });
    };
  }
});

test("class field order", () => {
  class N {
    l = 455;
  }
  class M {
    u = 4;
    @d1 w = 9;
    constructor() {
      // this.w = 9 should be moved here
      expect(this.u).toBe(4);
      expect(this.w).toBe(9);
      this.u = 3;
      this.w = 6;
      expect(this.u).toBe(3);
      expect(this.w).toBe(6);
    }
  }

  function d1(target, propertyKey) {
    expect(target === M.prototype).toBe(true);
    expect(propertyKey).toBe("w");
  }

  let m = new M();
  expect(m.u).toBe(3);
  expect(m.w).toBe(6);
});

test("changing static method", () => {
  class A {
    static bar() {
      return 1;
    }
  }

  @changeMethodReturn("bar", 5)
  class A_2 {
    static bar() {
      return 7;
    }
  }

  function changeMethodReturn(method, value) {
    return function (target) {
      target[method] = function () {
        return value;
      };
      return target;
    };
  }

  @changeMethodReturn("bar", 2)
  class B extends A {}

  @changeMethodReturn("bar", 9)
  class C extends B {}

  expect(A_2.bar()).toBe(5);
  expect(A.bar()).toBe(1);
  expect(B.bar()).toBe(2);
  expect(C.bar()).toBe(9);
});

test("class extending from another class", () => {
  class A {
    a: number;
    constructor() {
      this.a = 3;
    }
  }

  class B extends A {
    a: number = 9;
  }

  expect(new A().a).toBe(3);
  expect(new B().a).toBe(9);

  class C {
    a: number = 80;
  }

  class D extends C {
    a: number = 32;
    constructor() {
      super();
    }
  }

  expect(new C().a).toBe(80);
  expect(new D().a).toBe(32);

  class E {
    a: number = 40;
    constructor() {
      expect(this.a).toBe(40);
    }
  }

  class F extends E {
    @d1 a: number = 50;
    constructor() {
      super();
      expect(this.a).toBe(50);
      this.a = 60;
      expect(this.a).toBe(60);
    }
  }

  function d1(target) {
    target.a = 100;
  }
});

test("decorated fields moving to constructor", () => {
  class A {
    @d1 a = 3;
    @d2 b = 4;
    @d3 c = 5;
  }

  function d1(target, propertyKey) {
    expect(target === A.prototype).toBe(true);
    expect(propertyKey).toBe("a");
  }

  function d2(target, propertyKey) {
    expect(target === A.prototype).toBe(true);
    expect(propertyKey).toBe("b");
  }

  function d3(target, propertyKey) {
    expect(target === A.prototype).toBe(true);
    expect(propertyKey).toBe("c");
  }

  let a = new A();
  expect(a.a).toBe(3);
  expect(a.b).toBe(4);
  expect(a.c).toBe(5);
});

test("only class decorator", () => {
  let a = 0;
  @d1
  class A {}

  let aa = new A();

  function d1(target) {
    a = 1;
    expect(target).toBe(A);
  }

  expect(a).toBe(1);
});

test("only property decorators", () => {
  let a = 0;
  class A {
    @d1 a() {}
  }

  let b = 0;
  class B {
    @d2 b = 3;
  }

  let c = 0;
  class C {
    @d3 get c() {
      return 3;
    }
  }

  function d1(target, propertyKey) {
    a = 1;
    expect(target === A.prototype).toBe(true);
    expect(propertyKey).toBe("a");
  }
  expect(a).toBe(1);

  function d2(target, propertyKey) {
    b = 1;
    expect(target === B.prototype).toBe(true);
    expect(propertyKey).toBe("b");
  }
  expect(b).toBe(1);

  function d3(target, propertyKey) {
    c = 1;
    expect(target === C.prototype).toBe(true);
    expect(propertyKey).toBe("c");
  }
  expect(c).toBe(1);
});

test("only argument decorators", () => {
  let a = 0;
  class A {
    a(@d1 a: string) {}
  }

  function d1(target, propertyKey, parameterIndex) {
    a = 1;
    expect(target === A.prototype).toBe(true);
    expect(propertyKey).toBe("a");
    expect(parameterIndex).toBe(0);
  }

  expect(a).toBe(1);
});

test("no decorators", () => {
  let a = 0;
  class A {
    b: number;
    constructor() {
      a = 1;
      this.b = 300000;
    }
  }

  let aa = new A();
  expect(a).toBe(1);
  expect(aa.b).toBe(300000);
});